Investigation report: Placement of nasogastric tubes

1.1.1 NG tubes are passed through the nose down the back of the throat and through the oesophagus to the stomach (see figure 1) and are used to give medication, fluids or liquid feed to patients. NG feeding is typically a short- or mediumterm method of feeding. Patients may need NG feeding because:

• critical illness or unconsciousness leaves them unable to swallow at all
• neurological conditions such as stroke leave them at risk of not being able to safely swallow food or drink normally by mouth
• they have conditions that mean they cannot take in enough food and drink by mouth to meet their nutritional needs.

1.1.2 NHS Supply Chain data suggests that at least 967,977 NG feeding tubes with ENFit connectors (a brand of connector that enables syringes and other devices to be securely attached to NG tubes) were purchased between January 2019 and January 2020 (see table 1).

Figure 1: Route of a correctly inserted nasogastric tube

1.2.1 NG tubes have been the subject of numerous patient safety alerts in the last 15 years, and misplacement of these tubes in the respiratory tract is a ‘Never Event’ (see section 1.4) if it is not detected before starting a feed, or administering fluid or medication (NHS Improvement, 2018b). Table 2 summarises the safety alerts and guidance released in relation to misplacement of NG feeding tubes since 2005.

1.4.1 Never Events are patient safety incidents that are considered preventable because national guidance or safety recommendations exist that provide strong systemic protective barriers which should have been implemented by healthcare providers (NHS Improvement, 2018b).

1.4.2 Never Events have the potential to cause significant physical harm, as well as psychological harm to patients, families and staff.

1.4.3 Despite interventions to date, Never Events continue to occur in the NHS, with difficulties in identifying technical solutions to prevent recurrence. Past work has often focused on administrative interventions, increased education and more checks.

1.4.4 Never Events relating to NG tubes are declared when the tube has been misplaced into the respiratory tract and this has not been detected before feeding, flushing, or administering medication.

1.4.5 The strong systemic barriers in the case of misplaced NG tubes are described in the 2016 patient safety alert and resource set (NHS Improvement, 2016a; NHS Improvement 2016b). However, consistent human interactions are required to prevent NG tube incidents occurring.

1.4.6 Table 3 shows the number of incidents of misplaced NG tubes reported to NHS England and NHS Improvement (NHSE/I) since April 2015.

2.1.1 The reference event occurred in a critical care unit at a large acute hospital.

2.1.2 Critically ill patients may need sedation, support for breathing, multiple infusions of medications and fluids, and require complex monitoring. Critically ill patients usually receive one-to-one care from a dedicated nurse.

2.1.3 The patient involved in the reference event required admission to the critical care unit for care of his head injury and support with his breathing.

21 December 2018

2.2.1 Fabian, a man aged 26 years, was admitted to an emergency department on 21 December 2018 following a fall from his bicycle. Fabian swerved to avoid a motor vehicle and hit his head on a pavement, suffering a head injury. It was observed that Fabian was having seizures at the scene of the accident and when he arrived at the hospital. Because of this, Fabian was placed in an induced coma by an anaesthetic team prior to having a head-to-toe CT scan (a scan which uses X-rays and computer technology to create detailed images of the inside of the body). Fabian was transferred to the critical care unit for ongoing care at 20:01 hours.

2.2.2 To ensure Fabian’s nutritional needs were met, a plan was made to insert an NG tube. A nurse inserted the tube on the evening of 21 December 2018. The tube was secured at 61cm at the nose [2]. Tube placement was confirmed by 5ml gastric aspirate with a pH of 2. Aspiration (obtaining a small amount of fluid by suction into a syringe) can be used as a method for confirming safe NG tube placement without the additional need of an X-ray if the pH is within a ‘safe range’ of pH 1 to 5.5 [3]. Therefore, in accordance with guidelines in place at the time, enteral feed was commenced at a rate of 25ml/hour.

2.2.3 On the same evening, Fabian had a catheter inserted into his right internal jugular vein. A chest X-ray was taken thereafter which showed a right sided pneumothorax [4]. A right-sided chest drain was inserted to drain the chest cavity of air.

22 December 2018

2.2.4 At 12:01 hours, Fabian was seen by neurosurgical team staff who confirmed they were happy for Fabian’s sedatives to be reduced. Fabian was seen by a critical care consultant on the daily ward round at 12:30 hours. A plan was made to commence a reduction in sedative infusions to begin the process of weaning Fabian from mechanical ventilation, and to allow assessment of his neurological status.

2.2.5 At approximately 15:45 hours, Fabian became agitated and started reaching for his breathing tube. During this episode, he pulled his NG tube out. His NG feed was stopped.

2.2.6 Following the period of agitation and subsequent removal of his NG tube, Fabian remained on a significant amount of sedation. He was recorded as being ‘deeply sedated’ (RASS -5) [5], apart from at 22:00 hours, when it was recorded in his notes that he was ‘moderately sedated’ (RASS -3).

2.2.7 A senior sister inserted a new NG tube at approximately 17:00 hours. The tube was secured at 57cm at the nose. An aspirate of 2ml was obtained which was recorded as being pH of 3.0. It was therefore considered safe to re-commence feeding.

2.2.8 At 17:08 hours, Fabian’s oxygen requirements increased from 21% to 30%. There was a suspected pulmonary aspiration (accidental inhalation of an object, food or fluid into the windpipe and lungs) on admission, therefore it was not considered unusual for Fabian’s oxygen requirements to increase. Figure 2 shows the gradual increase in Fabian’s oxygen requirements from the point of insertion of the second nasogastric tube, until a chest X-ray was performed showing the nasogastric tube sited in the left lung.

Figure 2: Increase in Fabian’s oxygen requirements

3.1.1 Nasogastric (NG) tubes are used to deliver both food and medication to patients. There is a risk of serious harm if tubes are incorrectly placed in the lungs rather than the stomach and this is undetected before they are used for feeding.

3.1.2 HSIB considered this as a potential issue for investigation following an email from a medical registrar who raised concerns about significant harm experienced by patients as a result of misplaced NG tubes.

3.1.3 Placement of NG tubes is confirmed initially by checking the pH of gastric aspirate with CE marked enteral pH test strips. If this aspirate test is unsuccessful, or the pH of the aspirate is not in the ‘safe range’, then an X-ray is undertaken to confirm NG tube placement. The referrer reported concerns that both checks can fail; this is supported by evidence from previous patient safety alerts and literature.

3.1.4 The 2016 patient safety alert (NHS Improvement, 2016a) described that the most common cause of placement errors was misinterpretation of X-rays by medical staff. Other causes included misinterpretation of pH tests by nursing and other staff, use of outdated checking methods, and communication issues between medical and nursing staff to confirm if tube placement was checked.

3.1.5 The referrer believed that these causes highlight that the risk for errors can affect all levels of staff, and that the seniority of the staff involved did not necessarily reduce the risk. The referrer stated concerns about seniority, as several trust responses to the 2016 alert involved restricting X-ray interpretation to consultant-level staff.

3.1.6 HSIB conducted a review of the Strategic Executive Information System (StEIS) and identified a reference event. Following initial investigation, the safety risk was assessed against HSIB’s investigation criteria, which are as follows:

Outcome impact – what was, or is, the impact of the safety issue on people and services across the healthcare system?

Misplacement of NG tubes is a Never Event and incidents reported to StEIS and the National Reporting and Learning System (NRLS) demonstrate that they can lead to severe harm or death. NG tubes are often required in patients who are critically ill, and the harm caused by feed entering the respiratory tract can be particularly severe in this group of vulnerable patients.

Systemic risk – how widespread and how common a safety issue is this across the healthcare system?

Misplacement of NG tubes is a Never Event when the tube has been misplaced into the pleura or respiratory tract and then this has not been detected before feeding, flushing, or administering medication. This type of Never Event persists across the NHS despite numerous patient safety alerts and safety initiatives.

Learning potential – what is the potential for an HSIB investigation to lead to positive changes and improvements to patient safety across the healthcare system?

The Trust investigation of the reference event did not identify a strong systemic barrier to prevent the misplacement of NG tubes. Evidence from the reference event investigation suggested there was potential learning around procurement, elements of pH testing strip design, factors that influence decision making and the current processes for confirming NG tube placement.

Investigative approach

3.2.1 The investigation considered the healthcare system in its entirety to identify the factors that contributed to the patient safety incident. The investigation was guided by systems engineering principles. These are used to identify and represent the causal flow of events and how these have been influenced by planning, management, and national guidelines.

Investigation team

3.2.2 The HSIB investigation team was multidisciplinary and included:

• nursing experience
• systems safety and human factors experience
• NHS regulatory experience
• clinical consultant medical staff with experience in quality improvement projects related to nasogastric tube safety.

Reference event investigation

3.2.3 The investigation interviewed Fabian and his Father to establish their experiences of the reference event. The staff at a major trauma centre who were involved in the reference event were interviewed. They included:

• the clinical director
• the consultant clinical governance lead
• intensive care consultants
• doctors in training
• nursing staff
• specialist nurses

National investigation

3.2.4 Following investigation of the reference event, the investigation considered existing guidance on the insertion and confirmation of NG tube placement, and the procurement, use and availability of the equipment required. This included a review of how staff acquire the competencies to do this safely.

Engagement (national investigation)

3.2.5 Stakeholders across the healthcare system were contacted and interviewed to establish their perspective on the national context. They included:

• NHS England and NHS Improvement National Patient Safety Team
• the research team at Imperial College London
• National Confidential Enquiry into Patient Outcome and Death
• Medicines and Healthcare products Regulatory Agency
• Department of Health and Social Care
• British Association for Parenteral and Enteral Nutrition
• National Nurses Nutrition Group
• Academic Health Science Networks and Patient Safety Collaboratives
• NHS Supply Chain
• Royal College of Radiologists
• The Society and College of Radiographers
• Health Education England
• British Standards Institution
• NHS healthcare providers
• Getting It Right First Time. Evidence gathering

3.2.6 Multiple sources of evidence were gathered and reviewed by the investigation, including:

• Fabian’s medical records
• interviews with Fabian and his Father
• relevant local and national policy and guidance
• relevant incidents reported to StEIS and NRLS
• fieldnotes from observation visits
• literature relevant to the identified safety risks.

3.2.7 The evidence gathering process adopted an iterative approach; as further information was gained, additional data sources were identified.

3.2.8 A semi-structured interview plan was developed to gather information on safety risks, and a thematic analysis was performed.

3.2.9 Observations were conducted using a framework for nonparticipant observation, and a thematic analysis was performed on the fieldnotes.

Analysis

3.2.10 The analysis process had the following aims:

• To generate findings.
• To develop visualisations of the system involved in the patient’s care pathway and a timeline of the events. This assisted in recognising communications, interactions and decision making.
• To develop a comprehensive understanding of the healthcare system so that safety recommendations could be identified, and their potential impact on the system could be considered.

3.2.11 These aims were achieved through the application of the following methods:

AcciMap method

3.2.12 The AcciMap model (Svedung and Rasmussen, 2002) was used to analyse the reference event information and support the direction of the national investigation. AcciMap is an incident analysis method that identifies factors within the system that influenced the occurrence of an incident. The analysis focuses on identifying relationships between the different levels of the system (see figure 3), which include government policy and budgeting; regulatory bodies and associations; local area management; physical processes and actor activities (what staff, people, organisations, systems did); and equipment and surroundings (Stanton et al, 2013).

4.1.1 Fabian had removed his first NG tube during a period of agitation. A senior nurse inserted a new NG tube, which was secured using tape. The nurse aspirated approximately 2ml of fluid through the tube. The nurse tested the aspirate on a pH strip which indicated a pH of 3.0. At interview, the nurse confirmed that nothing was flushed down the NG tube prior to the aspirate being obtained. There was no minimum requirement for aspirate required, however, 2ml was sufficient to test the aspirate on a pH strip.

4.1.2 A pH reading of 3.0 confirmed to the nurse that the aspirate was gastric in origin and feeding could be re-commenced. Fabian’s feeding regime commenced in line with policy and in accordance with Fabian’s nutritional needs.

4.1.3 The NG tube was later found to be in Fabian’s respiratory tract. The investigation conducted by the trust at which the reference event took place (referred to in this report as ‘the Trust’) (The Trust, 2019) considered two possible explanations as to how the pH of the aspirate obtained fell within the ‘safe range’ to commence feeding:

• The respiratory tract sample was acidic. The Trust considered whether the sample collected from Fabian’s respiratory tract was acidic because he had aspirated gastric contents into the bronchial tree (part of the lungs). The Trust concluded that no evidence of cases where this has occurred were found in the literature. Any acidic fluid in the lungs would rapidly disperse into the small airways, making it difficult to obtain an acidic sample. As such this scenario was considered by the Trust investigation team as unlikely.
• Error in pH testing. The alternative suggestion by the Trust investigation findings was that the incident resulted from ‘human error’ during pH testing. The investigation report referred to a report by NHS Improvement (2016a) which found that errors during pH testing were the second highest cause of Never Events involving NG tubes. The NHS Improvement report went on to say that of the reported errors during pH testing:

4.1.4 The HSIB investigation looked at process 1 - the confirmation of NG tube placement using pH testing. The intended goal of the process is to ensure that an NG tube is in the stomach to allow commencement of feeding. The outcome in the reference event was that the NG tube was inadvertently placed in the respiratory tract.

4.1.5 The following sections explore the work system factors associated with this process.

National policy and alerts

4.2.1 In 2016, NHS Improvement published a resource set, entitled ‘Initial placement checks for nasogastric and orogastric tubes’ (NHS Improvement, 2016b), to support the associated patient safety alert ‘Nasogastric tube misplacement: continuing risk of death and severe harm’ (NHS Improvement, 2016a). The alert was aimed at trust boards to support exploration of whether they had systems in place to support staff to deliver safety-critical requirements for initial nasogastric and orogastric tube placement. The associated resource set outlined safety-critical requirements for confirming tube position.

4.2.2 In England there are two main types of test for confirmation of NG tube placement: pH strips and X-ray (NHS Improvement, 2016b).

4.2.3 NG tube placement can initially be checked by testing the pH of aspirate (stomach fluid which has been drawn out of the NG tube using a syringe) using pH strips or pH paper. This is typically done by a healthcare professional and is intended to indicate whether the NG tube is in the gastrointestinal tract or, if the test is inconclusive, that it is unclear where the NG tube is placed.

4.2.4 In the national patient safety alert ‘Reducing the harm caused by misplaced nasogastric feeding tubes in adults, children and infants’ (National Patient Safety Agency, 2011), it was mandated that all areas where NG tube placement was likely to occur had access to pH indicator paper that was CE marked and manufactured to test human gastric aspirate.

4.2.5 The pH strip changes colour when an acid or alkaline substance is placed onto it. Gastric secretions are normally acidic, whereas secretions found in the respiratory tract are usually more alkaline. As such, an acidic pH (pH equal to or less than 5.5) would indicate the NG tube is correctly placed in the stomach and it is safe to commence feeding.

4.2.6 In its 2011 alert the National Patient Safety Agency did highlight the potential difficulty experienced by some staff in differentiating pH readings that fell between pH 5 and 6 using (currently) available pH indicator paper. It was therefore recommended that a second competent person checks any readings that fell within the pH range of 5 to 6 (National Patient Safety Agency, 2011).

4.2.7 The NHS Improvement resource (2016b) did advise that ‘no local or national clinical guidance should widen the safe range’. The resource set noted that the ‘safe range’ for excluding respiratory placement may need to be integrated in local guidance with use of different pH ranges for other purposes (for example, tighter pH ranges to distinguish oesophageal from gastric placement). It went on to say that ‘to narrow the current ‘safe range’ of pH, such clinical guidance would be expected to have followed NICE [National Institute for Health and Care Excellence] accredited processes of guidance development, including risk-assessment of the impact of this change of practice’. At the time of writing, no new evidence-based national clinical guidance has been published to narrow the ‘safe range’.

4.2.8 Sometimes no aspirate can be obtained following NG tube insertion, or the pH of the fluid aspirated is not in the ‘safe range’ (particularly when patients are on medication intended to reduce gastric acidity). If the result is not acidic (that is, the pH is greater than 5.5) or is inconclusive, an X-ray is required to check that the NG tube is positioned in the stomach and not in the lungs (National Patient Safety Agency, 2005a; National Patient Safety Agency, 2011).

4.2.9 The National Patient Safety Agency alert (2011) recognised that even in cases of correct NG tube placement, it is possible for the tube to migrate or be dislodged away from the stomach and into the oesophagus or lungs. If this occurs during feeding it could prove fatal. Because of this, the alert referred to additional guidance by the British Association of Parenteral and Enteral Nutrition (BAPEN) which recommended that repeat placement checks (including aspirate pH) were made:

• before administering each feed
• before giving medication
• at least once daily.

4.2.10 Previous Never Events have been linked to dislodgement after correct initial placement (NHS Improvement, 2016b). It is possible that intubation or some forms of respiratory suction could move a previously correctly placed NG tube to the respiratory tract, although reports suggesting this are very rare. The NHS Improvement resource set refers to checking the external tube marking for displacement. However, an unchanged external tube length cannot in itself exclude the possibility of internal displacement (NHS Improvement, 2016b). The guidance highlights that as there are no other definitive safety-critical steps that could be taken, advice on repeat placement checks remains an area for local and professional clinical guidance.

Research regarding reliability of pH testing strips

4.2.11 NHS Improvement (2016b) conducted a review of 95 NG tube incidents reported to the Strategic Executive Information System between 12 September 2011 and 11 March 2016. They found that the second most common type of error involved issues with pH checks (incorrect X-ray interpretation was the most common). Of the 95 incidents, 23 related to pH testing and of these, 15 of the 23 incidents may describe a pH in the ‘safe range’ having been found even though the NG tube was subsequently found to be in the respiratory tract. The limitations of these investigations are referred to in NHS Improvement’s (2016b) review.

4.2.12 Fernandez et al (2010) conducted a systematic review of research into the diagnostic performance of biochemical tests (for example digestive enzymes including bilirubin, pepsin and trypsin) used to determine placement of NG tubes after insertion in adults. Of the 10 studies included in the review, seven investigated the diagnostic accuracy of pH, one investigated the diagnostic accuracy of pH and bilirubin respectively, two a combination of pH and bilirubin and one a combination of pH, pepsin and trypsin levels in identifying NG tube position. Bilirubin coupled with pH demonstrated the ability of the test to identify misplaced tubes in the intestine. However, the ability of the test to correctly identify gastric placement of feeding tubes was relatively low. The review was critical of the evidence available and so was unable to draw conclusions about the diagnostic performance of the different tests.

4.2.13 Work conducted for the NHS Patient Safety Research Portfolio in 2010 (Hanna et al, 2010) recommended changing the cut-off from a pH of 5.5 to a pH of equal to or less than 4.0 to verify gastric position. Patients with pH between 4.0 and 5.5 were recommended to have an assessment of risk. For a pH of 5.5 or higher, feeding should only start if an X-ray had confirmed stomach placement. One reason provided for this recommendation was the variety of pH papers in use at that time, some of which were not accurate enough and had potential for underestimating pH.

4.2.14 A more recent study highlighted that the pH testing of gastric aspirate can be associated with false positive and false negative readings. There was often disagreement between observers when pH readings were borderline (Rowat et al, 2018).

4.2.15 In a review of guidelines associated with NG tube insertion (Metheny et al, 2019), it was concluded that pH testing of NG aspirate was the most favoured non-radiological method for checking NG tube position. However, there was a lack of consensus on the best pH cut-off point; values of pH 4.0, 5.0, and 5.5 were cited in the guidelines (Metheny et al, 2019). The investigation was also informed of variation in the best cut-off point for pH and in some cases were told that X-ray was the mandated first-line check.

4.2.16 Some organisations in England have narrowed the ‘safe range’ and included this in their own local policy with a rationale as to why, for example:

The investigation reviewed other hospital policies and found that some trusts have used a pH of 4.0 as their cut-off ‘safe range’.

4.2.17 A small survey undertaken by BAPEN found six cases where a pH of equal to or less than 5.5 led to feeding and a Never Event. BAPEN reported that it could not be sure whether the protocols for reading pH were followed or not, but the alternative explanation was that the tube was sited in aspirated gastric contents within the lungs. BAPEN emphasised that an acid pH only shows the aspirate is acid, not where it was derived from. The question of obtaining an acid pH from a lung aspirate was also considered by the investigation, which included discussion with representatives of BAPEN who shared that while this is possible, there was no evidence to back this up (Personal communication, BAPEN, 13 July 2020).

National guidance for education around NG tube position checks

4.2.18 NHS Improvement’s resource set (2016b) highlighted that in its review of incidents, X-ray and pH testing had often been carried out by staff who had not received competency-based training, and therefore did not follow the safety-critical requirements. The resource states that:

4.3.1 There were two applicable local policies for the staff involved in the reference event to follow. There was a Trust-wide policy for the safe insertion and management of NG tubes (The Trust, 2018a) and a specific guideline for initiating NG feeding in critical care (The Trust, 2018b). There was also a supplementary Trust-wide policy for initiation of NG feeding although this excluded critical care (The Trust, 2015). The policies were all accessible via the Trust intranet and were in date at the time of the reference event.

Local Trust-wide NG tube policy

4.3.2 The Trust-wide policy covered the insertion of all NG tubes. All supplementary policies which discussed NG tube insertion or confirmation referred to this overarching policy. The policy was 22 pages long and included flowcharts for staff to follow. The investigation identified that the Trust’s policy was in line with recommended national guidance.

4.3.3 Staff told the investigation they knew the policies existed but that they were too long to read.

4.3.4 The Trust’s policy instructed staff to ‘test aspirate using CE marked paper/strips’. A pH of 5.5 or below confirmed gastric placement, and feeding could commence. The policy directed the person inserting the NG tube to ‘record the marker of length of the NG tube at the nose (this should usually be within 54-60 centimetres)’. If confirmation of placement could not be achieved by a test of gastric aspirate pH, the policy outlined alternative steps to follow to confirm NG tube placement.

Local critical care NG tube guideline

4.3.5 The Trust’s critical care unit had a specific guideline (The Trust, 2018b) for initiating and early monitoring of NG feeding. The guideline was designed to allow for safe and appropriate initiation of enteral tube feeding within 24 hours of a patient’s admission to the critical care unit. The critical care guideline referred directly to the Trust-wide NG tube insertion policy (The Trust, 2018a). The critical care guideline included those patients in which NG feeding should be avoided or given cautiously. The guideline did not replace discussion with senior clinicians as required.

4.3.6 Patients in the Trust’s site’s critical care unit were fed over 24 hours, with a very short pause in feeding once a day to re-test the tube position. The critical care policy had a flowchart checklist for this confirmation of existing NG tube position. Staff were directed ‘at midnight every 24 hours minimum, [to] check and record the pH’ (see figure 5).

Figure 5: Confirmation of existing NG tube position checklist (The Trust, 2018b)

4.4.1 NG tube insertion is a skilled task that, according to the Trust’s policy, should only be carried out by experienced and competency assessed healthcare professionals (The Trust, 2018a).

4.4.2 When healthcare professionals insert an NG tube, they are unable to see whether the NG tube is being correctly placed into the stomach. Staff may believe they will see some signs of distress or coughing if the tube is misplaced, but many reports of tube misplacements indicate that the positioning of the tube incorrectly into the airway and lung caused no signs or symptoms at all.

4.4.3 The nurse who inserted Fabian’s new NG tube after the original tube had become dislodged reported that Fabian had coughed while the new tube was being inserted. The nurse had paused the NG tube insertion and continued to insert the tube once he had finished coughing. The nurse commented that it was a small cough which they did not perceive as significant. They were also aware that they would be checking the placement of the NG tube afterwards by pH testing the aspirate.

Reliability and usability of pH testing

4.4.4 During an observational visit to the Trust, the investigation found that the process of pH testing could be unreliable. There was also reported confusion about when to test pH aspirate once a feed has commenced. A nurse reported, and the investigation observed, that stomach aspirate drawn once feeding had commenced could have a pH of 5.5 or above.

4.4.5 The investigation found research that identified another reported case of false-positive pH aspirate, thought to be related to the effect of an advanced head and neck cancer (Sellers, 2012). National and professional guidance (National Patient Safety Agency, 2011) does not recommend the use of pH testing for patients with known neck or chest anatomical issues.

4.4.6 Stomach pH can be altered by the use of some medications, for example, acid-supressing medications. Very little data exists on how medication affects the pH of the stomach (other than acid suppression medication), so it is not possible to obtain this from medicine information sheets or other clinical evidence. Other additional factors that can affect the stomach pH include the feed itself, 24-hour feeding, and infection. The limitations of obtaining an accurate pH reading in these circumstances is also reflected in national guidance.

4.4.7 Borsci et al (2017) reported that professionals underestimate the complexity of using pH strips to ascertain the position of an NG tube. The process of positioning and checking the tube using pH strips is a multi-task process with various points requiring decision making. The usability and experience of the use of pH strips among professionals was considered poor (Borsci et al, 2017). Misinterpretation of the colour of pH strips has also been reported to be common (Taylor and Clemente, 2005). In both studies, the researchers challenge the idea that pH testing is an appropriate firstline check.

Patient

4.5.1 Fabian was actively being weaned from his sedation following review by the neurologist at 12:52 hours on 22 December 2018. Fabian pulled his NG tube out at 15:45 hours. This was the first time he had suddenly woken up. The Trust reported that it would have been very difficult to predict that the transition from deep sedation to agitation would occur so rapidly. Staff told the investigation that the amount of time it takes to wean a patient off sedatives depends on a variety of factors. These include the patient’s presenting clinical condition, the type of sedation, the length of time they have been under sedation, and other factors.

4.5.2 Fabian was unconscious at the time the original and second NG tube was inserted.

Staff

4.5.3 The senior nurse who inserted Fabian’s second NG tube, reported that at the time they were not aware that there were two types of pH testing strips with different pH scales in circulation. This highlights a risk associated with implementation of new equipment and devices.

pH strip storage

4.6.1 The Trust’s critical care unit had an ‘enteral feeding cupboard’ which contained all the required equipment for enteral feeding.

4.6.2 The Trust investigation team found that boxes of pH testing strips, both CE marked and non-CE marked, were kept together in a basket in the enteral feeding cupboard. The pH strips were very similar in appearance. As such, it was possible that in the reference event, the strip was compared to the colour chart on the wrong container and gave false reassurance that the NG tube was correctly placed.

Critical care environment

4.6.3 Fabian was being cared for within a critical care unit at a large acute hospital. It was not a modern facility and had not been specifically designed for its purpose.

4.6.4 The Trust’s policy for safe insertion and management of NG tubes (The Trust, 2018a) stated that pH paper should be interpreted immediately in a well-lit area. The HSIB investigation observed that the Trust’s critical care unit had no natural light, and the lighting levels were variable throughout the department with some areas of the department being particularly dark. The investigation observed one nurse moving around their patient’s bed space, holding a pH testing strip in an area with greater light levels to accurately interpret the testing strip.

4.6.5 The investigation also observed nurses using torches to aid their vision. The dark environment could have impacted staff members’ ability to correctly interpret pH testing strips.

4.6.6 The unit was crowded with equipment trollies, it was described as noisy, and there were well-known risks associated with the layout of the unit which had been escalated to the risk register. Robust plans were in place for a redesigned critical care unit. The staff were observed to be working well within these limitations and had a shared mental model of the risks and the actions necessary to minimise them.

Critical care bed spaces

4.6.7 The investigation observed that the nurse went to the drawer of the patient bedside workstation to get the pH testing strip.

4.6.8 Each patient bed space contained a movable bedside workstation in which was stored equipment the nurses required for routine bedside tasks. The investigation observed that there was no consistency in terms of the equipment each bedside workstation contained or the location in which the equipment was stored.

4.6.9 The investigation observed that equipment could be placed together in the same drawer with no compartmentalisation, requiring staff to search to find an item they required.

4.6.10 Nurses commented that they could configure their bedside workstation to suit their personal preferences.

4.6.11 Limitations in the organisation and consistency of bedside workstations increases the likelihood that staff may not find the equipment they require or select the wrong item.

Summary of process 1: confirmation of NG tube placement using pH testing

1. The process of confirmation of correct NG tube placement using pH testing strips is potentially unreliable and its complexity underestimated. The pH test cannot be used if stomach contents cannot be aspirated and will be inconclusive in patients with altered stomach pH. The investigation also identified concerns about the reliability and usability of pH strips.
2. There is a risk that organisations that insert NG tubes may have multiple types of pH testing strips in circulation, both CE marked, and non-CE marked.
3. Testing strips are ‘read’ by checking the colour on the strip against a colour chart on the container the strips are kept in. CE marked enteral pH testing strips from different manufacturers have different pH colour coding scales which are inconsistent. If a healthcare provider has more than one type of enteral pH testing strip in circulation at the same time, there is a risk of error when comparing the strips from one product against a container with a different pH scale. Therefore, having two or more types of CE marked strips in circulation could result in inaccurate readings.
4. The multiple types of strip present in the Trust where the reference event took place highlights the need for trusts to have reliable processes in place to implement changes that are required by national guidance – in this case, the removal of non-CE marked pH testing strips for testing human gastric aspirate.
5. There is no standard process on how to read a pH strip. A standard process needs to be defined.
6. Training for NG placement is available albeit variable in terms of delivery and content. The cascade model of training (where one group of staff is trained, then each trained staff member trains another group, and so on) has led to some staff ‘teaching’ the incorrect method of testing pH.
7. There is no consistent process for assessing and recording competency in NG tube placement and confirmation using pH testing.
8. There are clinical guidelines on the ‘safe range’ for pH and some trusts use a lower pH due to a perception that a lower pH is safer. Although a range of research has been carried out, there is no consistent research conclusion to guide what the best cut-off pH is to exclude placement in the respiratory tract. There is concern about use of ‘safe range’, and there have been no accredited clinical guidelines or research that would change the ‘safe range’.
9. The environment within which pH testing strips are being interpreted can increase the risk of error. In the reference event, this was particularly noted with the poorly lit environment.

HSIB makes the following safety recommendations

National policy and alerts

4.8.1 There is a significant amount of legislation that determines how X-rays are performed, who can refer a patient for an X-ray, who can interpret an X-ray for clinical decision making and who can formally report on an X-ray (Department of Health and Social Care, 2018; Department of Health and Social Care, 2017; Royal College of Nursing, General Chiropractic Council, General Osteopathic Council, Chartered Society of Physiotherapy, NHS Alliance, The Royal College of Radiologists and Society and College of Radiographers, 2008). Appendix B is a summary of the relevant legislation and subsequent guidance.

4.8.2 The responsibility for how the legislative and regulatory guidance is implemented rests predominantly with local trusts.

4.8.3 The resource set ‘Initial placement checks for nasogastric and orogastric tubes’ (NHS Improvement, 2016b) states that X-ray can be used to confirm NG tube placement but is not recommended for routine use in all patients. Testing the pH of aspirate can be used as a first-line method for confirming safe NG tube placement. X-ray would be required if aspirate pH in the ‘safe range’ (pH 1.0 to 5.5) could not be obtained, and for patients where confirmation of optimum gastric placement was necessary. X-ray may be required in other specific scenarios and such cases should be preceded by robust assessment.

4.8.4 The NHS Improvement guidance (2016b) also highlights that X-ray request forms should clearly state if the purpose of the X-ray is to establish NG tube position. This is to ensure that radiologists and radiographers interpret the X-ray using the ‘four criteria’ for gastric placement of NG tubes. In addition, stating the purpose, for example for NG tube placement confirmation, ensures that the image is adequate for an NG tube check as it will show more visibility below the diaphragm than a standard chest X-ray.

4.8.5 Interpretation of the X-ray for NG tube placement would typically be done by certain medical staff, trained radiographers or by radiologists.

4.8.6 In a review of guidelines associated with NG tube insertion (Metheny et al, 2019), it was found that X-ray, when properly performed and interpreted, was the most accurate method for confirming NG tube placement. X-ray was generally supported for high-risk patients, for example, for those who were critically ill or had an altered level of consciousness or a diminished or absent gag reflex. However, X-rays cost more and caused delays in commencing feeding and inconvenience for patients and staff, as well as exposing patients to radiation.

4.8.7 The investigation identified variability in interpretation of when to use X-ray and that local policies differ.

4.8.8 The NHS Improvement review of NG tube incidents reported to the Strategic Executive Information System (StEIS) between 12 September 2011 and 11 March 2016 (NHS Improvement, 2016b) found that incorrect X-ray confirmation was the most common cause of NG tube incidents.

National guidance for education around NG tube position checks

4.8.9 There is a national requirement to ensure that all healthcare professionals involved with NG tube position checks have been assessed as competent through theoretical and practical training (National Patient Safety Agency, 2011).

4.8.10 The resource set produced by NHS Improvement (2016b) recognised that not all trusts had created ongoing training programmes, or levels of training completion had not been routinely monitored and had lapsed. They found that training may be perceived by trusts as unnecessary for experienced or senior staff. Alternatively, trusts may perceive that newly registered nursing staff and junior doctors must already have had their competencies assessed during their training.

4.8.11 The NHS Improvement resource set (2016b) summarised the safety-critical requirements for confirming initial NG tube placement. It highlighted that competency-based training needed to reflect all the safety-critical requirements summarised in the resource set.

4.8.12 The resource set stated that training for X-ray interpretation of NG tube placement should include ensuring that the X-ray viewed is the most current, ensuring the four criteria approach for confirming gastric placement is implemented, and providing clear instruction and communication whether it was ‘safe to feed’. It also recommended having structured documentation to assist recall of this process and associated training.

4.8.13 The investigation reports and data that informed the resource set were recognised by NHS Improvement to have limitations. Data was obtained from National Reporting and Learning System reports and StEIS, where the information provided varied from a short description to several hundred words summarising the investigation. As such, some detail may have been missing.

4.8.14 Trust investigations are also known to have limitations (NHS Improvement, 2016b; Toft, 2015). A review into the quality of trust investigation reports (Care Quality Commission, 2016) found that nearly 75% contained unanswered questions or unexplained issues, leaving the focus on staff acts or omissions. Too often the investigation reports identified the causal factors as staff failing to follow trust policy and procedures. The lack of a systems approach to these investigations meant recommendations were focused on staff, such as reminding them to follow policy and procedure, and to conduct further training. The Care Quality Commission review highlighted that retraining staff was not always the right solution.

4.8.15 Many of the findings described in the NHS Improvement review (2016b) which were related to X-ray interpretation highlighted training as a key factor. However, it is possible that owing to limitations in the quality of investigations reviewed, the wider system factors associated with X-ray interpretation were not explored. As such, there may be an overemphasis on training as a mitigation for reducing errors in X-ray interpretation.

4.8.16 In 2016 a trust undertook a system-wide evaluation of its practice in relation to the placement and confirmation of NG tubes (Earley, 2019). The evaluation identified several issues, including that 90% of advanced nurse practitioners and doctors who were involved in confirming NG tube position using X-ray had received no specific training. The trust found there were a lot of resources to support education and training, but there was a gap in how to assess competency, particularly for using X-ray to confirm NG tube placement.

4.8.17 The trust designed an e-learning package which was co-designed with clinical staff and relatives of a patient who had experienced an NG tube related Never Event. The e-learning package reflected the safety-critical requirements highlighted by NHS Improvement (2016b), there was an assessment function as part of the package, and it was made mandatory for all staff to complete.

4.8.18 As part of the e-learning package, a five-point approach was developed using the mnemonic NEX, 2Cs and 2Ds to highlight the required areas to review on an X-ray to check NG tube placement. The mnemonic prompted staff to review the measurement between different parts of the anatomy: from the Nose to Ear to Xyphoid process (NEX), then the anatomical landmarks Carina and Clavicle (2Cs), and finally the Diaphragm and Deviation (2Ds). A standardised approach to documenting the findings and rigorous audit and reporting were also reported to have been implemented.

4.8.19 This initiative won the patient safety improvement category in the 2018 Nursing Times Awards. Health Education England adopted the e-learning package as part of its educational platform. Evidence from a formal evaluation of the e-learning tool demonstrated a statistically significant improvement in the workforce’s capability (Earley, 2019).

4.8.20 The investigation was told of another trust’s approach to competency-based training following two Never Events due to misinterpretation of NG tube position on X-ray. The trust has developed an online platform which delivers teaching and assessment for individuals who review X-rays for correct positioning of NG tubes (RAIQC, 2020). The platform includes teaching slides explaining what the correct positioning should be, followed by 30 training cases where users review diagnostic-quality imaging and make a judgment about whether it is safe for the patient to be fed. They are required to review all 30 cases correctly before receiving a competency certificate. This can be exported to their e-portfolio as evidence of training completion. Since the implementation of this training tool, there have been no NG tube related Never Events at the trust. The investigation was told that other hospitals had used the training and that with the support of the Oxford Academic Health Science Network, the training will be implemented across the Thames Valley region.

4.8.21 Despite the above examples of initiatives to improve staff competence, training in England is not standardised and is not combined with a broad array of changes, such as equipment, organisation, supervision, teamwork and the application of human factors principles to these changes (Leape et al, 2002).

Local policy for X-ray interpretation of NG tubes

4.9.1 The Trust’s policy for the safe insertion and management of a NG tube outlined how medical staff should assess NG tube position when interpreting a ‘chest X-ray’. The Trust policy referred to chest X-ray or CXR and did not specifically state NG X-ray:

‘The chest X-ray must be reviewed within two hours to avoid delays in feeding, by competency assessed personnel who have undertaken the e-learning package on NGT confirmation using CXR via the Trust blended learning system.’

The policy highlighted that a chest X-ray must be performed and viewed by a doctor/ nutritional nurse specialist and the result of the X-ray documented.

4.9.2 The Trust policy stated that

‘…the position of the tube should be documented in the medical notes prior to it being used, using either the ‘NGT position assessment using chest X-ray’ stickers, or if using free text in electronic systems, minimum data must include:

• correct patient i.e., patients name, hospital number and ward
• correct chest x-ray i.e. patients X-ray number
• date and time it was taken
• who reviewed it
• assessment of position using the 2C’s and 2D’s approach (clavicle, carina, diaphragm and deviation)
• if correctly positioned, documented that it is safe to use
• if not correctly positioned, then the action required i.e., remove, reposition and re-test or advice sought if unclear.’

4.9.3 The Trust had created a chest X-ray proforma to aid X-ray interpretation. However, staff reported that this was not always used. Reasons given were that the proforma was relatively new and some staff continued with their more familiar ways of working.

4.9.4 In Fabian’s case, an X-ray to confirm his NG tube position had not been required as the gastric aspirate obtained fell within the ‘safe range’.

Local education and training

4.9.5 The Trust followed the Health Education England e-learning package described in paragraphs 4.8.17 and 4.8.18.

4.9.6 Both the ST5 and ST7 who were involved in Fabian’s care reported having completed the Trust’s e-learning package. They described the process for reviewing NG tube placement using chest X-ray, although neither described the ‘NEX, 2Cs, 2Ds’ mnemonic precisely. It was reported that there were also numerous systems that doctors could use for general X-ray interpretation (when the purpose of the X-ray is not for confirming NG tube placement). It was reported that staff used whichever system they found easiest to remember.

4.9.7 The investigation found that although the Trust had resources available to support nurses’ and doctors’ education and training, there were limitations in how to assess competency for confirming NG tube placement. The competency assessment following the e-learning package guided participants through the required checks but did not always assess staff performing the task itself.

4.9.8 There were also limitations in how competencies among staff were tracked and monitored at the Trust.

4.9.9 All the staff involved in Fabian’s care told the investigation they had been trained in confirming NG tube placement using pH testing or X-ray through the Trust’s e-learning package.

Interpretation of chest X-rays for NG tubes

4.10.1 While the most accurate method for confirming correct NG tube placement is X-ray, there have been multiple reports of X-rays being misinterpreted by clinicians leading to patient harm.

4.10.2 The limitations of using X-ray to confirm NG tube placement include:

• exposure to radiation
• unsustainable demand on X-ray equipment leading to delays in feeding
• the delay in waiting for a feed to commence due to clinician availability to interpret X-ray
• the potential for misinterpretation
• accessibility issues for those people requiring NG feeding in the community
• increased hospital moves of seriously ill patients between wards and departments.

4.10.3 Interpretation of X-rays requires an understanding of background information and context. In the reference event:

• The ST7 reported that doctors did not routinely insert NG tubes. The responsibility for NG tube insertion, following protocols for tube placement and the management of the NG tube, belonged with nursing staff.
• The ST5 and ST7 doctors who were caring for Fabian overnight on 22 and 23 December 2018, reported that they were not aware that Fabian had removed his initial NG tube and that a new one had been re-sited at 17:00 hours on 22 December 2018.
• Nursing staff were required to document NG tube insertion, changes, and the checks they had performed. However, the investigation reviewed a hard copy printout of the electronic medical records and found that the records only referred to the initial NG tube insertion. The investigation was told if information was not uploaded to the electronic patient record system correctly, for example, new NG tube insertion dates, then the latest NG tube insertion date may not be displayed.
• The ST7 reported that in their mind, Fabian had been on enteral feed for two to three days and so the NG tube did not form part of his decision making for causes of clinical deterioration.

4.10.4 Interpretation of X-rays is also influenced by perceived and actual time pressures and competing demands. In the reference event:

• Both the ST7 and the ST5 who reviewed Fabian’s chest X-ray reported that the unit was busy, and staff were experiencing time pressure when reviewing the chest X-rays.
• The ST7 reported that it was not unusual for doctors to take short-cuts when looking for an abnormality in a chest X-ray because of feeling rushed. They reported that there was a process for reviewing an X-ray, but they did not use this process when reviewing Fabian’s chest X-ray.
• The ST5 reported that they had been caring for another very ill patient who they had needed to spend a lot of his time with, and had occasionally checked on Fabian. When they reviewed Fabian’s chest X-ray, they reported: “I was needed at the bedside of another unwell critical care patient so there was an element of time pressure when reviewing the chest X-ray.” The ST5 stated that they felt rushed in their review of Fabian’s chest X-ray and did not use their usual, more rigorous, process when reviewing it.
• There was an additional opportunity for a consultant to have reviewed Fabian’s chest X-ray during the evening ward round. However, the ward round was described to be busy with interruptions and so the consultant only heard the ST7’s report of their chest X-ray findings.

4.10.5 When a patient has an X-ray, a radiologist, or a radiographer who has undertaken training to enable them to report on examinations, will usually report on the images. The radiology report will summarise the findings and may make recommendations such as the need for further investigations.

4.10.6 The Trust stated in its policy that radiographers could be used to confirm NG tube placement via X-ray, however, this was more on an elective basis and generally it would be done by doctors or radiologists.

4.10.7 The chest X-rays taken in response to Fabian’s clinical deterioration were not reported on by a radiologist or a radiographer. They were reviewed by the referring doctors involved in Fabian’s care and treatment. The investigation was told by staff that this is not uncommon in critical care.

4.10.8 When an image is described as having been ‘reported’ it means the radiologist or radiographer has finalised the report. It may be sent immediately by electronic means or take additional time if manual processes are used (Healthcare Safety Investigation Branch, 2019). The investigation was told that nationally there has been an increase in radiographs not being reported by radiology/ radiography staff, with reporting instead being delegated to local clinical staff. This is not uncommon (Care Quality Commission, 2018b). However, staff undertaking formal clinical evaluation must be adequately trained and entitled to perform this task as mandated by the Ionising Radiation (Medical Exposure) Regulations 2017 (IR(ME)R) (Department of Health and Social Care, 2017). It is possible that, as has been described by the doctors involved in Fabian’s care, people look for an answer to the question they have about the patient rather than undertaking a systematic assessment of the image, which is what radiologists and reporting radiographers are trained to do (The Royal College of Radiologists, 2018).

Patient

4.11.1 The investigation observed that several tubes and lines could be seen on Fabian’s chest X-ray, only one of which is the NG tube (see figure 7). As such, the NG tube looks like other lines that normally would be seen in an X-ray for a patient in critical care.

Staff: inattentional blindness

4.11.2 It was likely that both doctors who looked at Fabian’s X-ray’ were influenced by ‘inattentional blindness’ when reviewing the chest X-rays. Inattentional blindness is a failure to see visible objects we may be looking at directly when our attention is elsewhere (Mack, 2003).

4.11.3 When the medical staff ordered the first chest X-ray for Fabian on 23 December 2018, the rationale for ordering the X-ray was to identify whether a chest infection was causing his condition to deteriorate. When the ST7 reviewed the chest X-ray at 12:58 hours, they noted what they considered to be pneumonia on the left-hand side of the lung. The ST7 made this assessment based on a history of aspiration of stomach contents at the time of the accident, which increased the risk of an infection presenting in the lung. The pneumonia fitted with their clinical assessment of Fabian’s deterioration. At interview, the ST7 stated, “you see what your mind wants to see”. Similar reports have been found in the literature and include expert observers (Drew et al, 2013) which also means expert observers also have made these types of error.

4.11.4 A further chest X-ray was undertaken at 00:29 hours on 24 December 2018, due to Fabian’s continuing clinical deterioration. A chest drain, which had been inserted to treat Fabian’s collapsed lung (pneumothorax) on the right side of his chest, had been removed earlier in the day. The ST5 doctor caring for Fabian was concerned that a re-accumulation of the pneumothorax could be the cause of the deterioration in his respiratory function. The X-ray was reviewed by the ST5; however, they also did not notice the misplaced NG tube. The ST5 told the investigation this was a “failure in X-ray interpretation… my mental model was consolidation”. They had mainly been focused on the right-hand side of the chest, and not where the NG tube was located (in the left lung).

4.11.5 The X-ray also showed an area of ‘clouding’ which was interpreted as pneumonia, which reduced the contrast between the NG tube and the area of accumulation making the misplaced NG tube more difficult to detect.

4.11.6 Both doctors were focused on clinical theories for Fabian’s deterioration that did not involve the NG tube. They were not directing their attention to the position of NG tube on the chest X-ray, and instead were looking for signs of infection or of a collapsed lung. When attention is focused on one object or task, it can be at the expense of noticing and attending to other available information (Mack, 2003).

Staff: fatigue

4.11.7 The length of shifts for both doctors and nurses at the Trust varied between 8 hours and 14 hours 15 minutes. Apart from one long day shift, night shifts tended to be the longest on average at 10 hours 45 minutes for nurses and 12 hours 30 minutes for doctors.

4.11.8 A conversation with a consultant revealed that in addition to a night shift, there may be additional tasks, activities, and commitments to be completed during daytime hours prior to the start of the night shift. As such, staff may have had limited rest prior to starting a long shift.

4.11.9 The investigation found that staff seemed to have a limited understanding of fatigue risks and how best to manage them. Senior staff reported that when designing a shift pattern, they considered staff perceptions, wellbeing, and work/life balance. While it is good that staff perceptions and wellbeing were being considered, the potential impact of the shift pattern on patient safety and on the likelihood of errors occurring did not seem to be a factor in the design of the shift patterns.

4.11.10 Some of the decisions and actions that occurred during Fabian’s care took place towards the end of a 12-hour shift, or at times of day when staff’s levels of alertness were likely to be reduced. For example, the second chest X-ray was reviewed at 01:20 hours. This is a time during which people naturally enter a ‘window of circadian low’ where overall performance and cognitive functioning are at their worst (Monk, 1988). The ‘window of circadian low’ is usually between the hours of 02:00 hours and 05:59 hours (Burban and Jackson, 2017). As such, the investigation was unable to rule out fatigue as a possible contributory factor in this incident.

4.11.11 Fatigue can have a detrimental effect on performance and increase the likelihood of human error. Wagstaff and Sigstad Lie (2011) conducted a systematic review of the literature on the effects of work hours on various health outcomes, safety and performance. The review found that work periods of eight hours and above carry an increased risk of an accident, and that the risk cumulates. Therefore, the risk of an accident at 12 hours is twice the risk at eight hours. The review found that shift patterns that included night shifts carried a substantial increased risk.

X-ray imaging software

4.12.1 At the Trust, X-ray images were reviewed on desktop computers and laptops within the critical care unit. The ST7 reported that these computers were not ideal as they could be slow to load the images.

4.12.2 The investigation observed that it took approximately 32 seconds for an X-ray image to load on a desktop computer in the trainee doctors’ office when the patient’s electronic record was already open. The investigation did not observe how long it took to load an X-ray image on a mobile laptop, but it was reported that this could be slower.

4.12.3 During its observation of the critical care unit, the investigation witnessed a discussion between medical staff which prompted a specialist doctor in training to review an X-ray on a mobile laptop to confirm NG tube placement. The doctor did not use the proforma which the Trust had developed for the NG tube check and had difficulties adjusting the contrast on the X-ray image to improve visibility of the NG tube. Importantly, this was a chest X-ray and not an NG X-ray. The investigation observed the consultant showing the doctor how to change the contrast.

4.12.4 A discussion with a junior doctor at the Trust revealed they were meant to review general chest X-rays on a high-resolution computer, but that did not always happen. The rationale given by staff at the time was that this was because of time pressures as it was quicker to look at X-rays on a laptop at the patient’s bedside.

4.12.5 The investigation concluded that the time delays in X-ray image loading would exacerbate the perceived time pressure doctors were experiencing. In addition, limitations in X-ray image quality and the capability to improve contrast may result in detail, such as a misplaced NG tube, being more difficult to see.

4.12.6 The investigation understands that the Trust’s radiology department has display screens and equipment which are better suited for displaying and thus interpreting X-ray images. National guidance by the Royal College of Radiologists describes standards for diagnostic display screen equipment that allows for optimised viewing of images (The Royal College of Radiologists, 2019a). However, it was reported that radiologists or a reporting radiographer did not typically interpret the critical care unit’s X-rays unless it was specifically requested. Radiographers are trained to identify and act upon unexpected and urgent findings even if not reporting radiographers (The Society and College of Radiographers, 2020).

Electronic patient records

4.12.7 The investigation identified that the way in which case notes were displayed on the Trust’s electronic patient record system may have made it difficult to identify key events such as NG tube displacement and re-insertion. The case notes were displayed as a long list, and so a record of the NG tube displacement and re-insertion may not have stood out and could have been missed.

4.12.8 The printout of events from an electronic patient record system does not enable easy retrospective review of key events and decision making. This had an impact on the investigation when analysing the electronic patient records.

X-ray interpretation environment

4.13.1 The ST7 doctor reported that interpreting an X-ray in the critical care unit environment was not ideal due to the distractions it presented. They reported that there would be other things going on around them, such as alarms sounding and staff conducting other tasks.

4.13.2 A consultant at the Trust reported that ideally X-ray images should be interpreted in a quieter environment where distractions were minimised. There was a small doctors’ office which was accessible for staff if needed.

HSIB makes the following safety observation

5.1.1 The reference event is not an isolated incident and misplaced nasogastric (NG) tubes continue to result in serious harm and death, despite safety alerts, guidelines, and resources to prevent Never Events. The former National Patient Safety Agency (NPSA) guidance stated that NHS trusts must comply with guidelines to prevent future Never Events.

5.1.2 People have shared their concerns that the safety culture and level of rigour applied to the insertion of NG tubes is not on a par with other interventions to support nutrition, for example feed administered through a vein, otherwise known as total parenteral nutrition (TPN). The President of the British Association of Parenteral and Enteral Nutrition shared his thoughts that this is a serious problem within our hospitals.

5.1.3 The investigation was made aware of a behavioural change approach to the implementation of NG tube placement patient safety guidance by the Bradford Institute for Health Research. The report headlines are below (Taylor et al, 2013).

5.2.1 pH strip readers that determine the colour of pH strips are available. However, there are conflicting reports about the accuracy / effectiveness of comparing pH paper to a calibrated hand-held pH meter (Fernandez et al, 2010). The accuracy and cost-benefit of pH strip readers were outside the scope of the investigation and were not considered further. It was reported by one trust that staff felt more reassured using a pH reader although the costs were significant. A pH reader was not used at the Trust where the reference event happened.

5.2.2 CORTRAK 2 EAS [9] is used as an adjunctive technology to aid in the placement of NG tubes (National Institute for Health and Care Excellence, 2016). It uses electromagnetic sensing technology to track and display the path of the feeding tube during a placement procedure and must be used with device-specific CORTRAK enteral feeding tubes. The accuracy and cost-benefit of CORTRAK 2 EAS was outside the scope of the investigation, however, it spoke to staff at one trust who had used the device in critical care when they could not rely on pH or failed to obtain an aspirate. CORTRAK was not used for confirmation of the initial NG tube placement but only for subsequent daily checks in this specific trust. Staff reported that the device reduced the requirement for X-ray confirmation. Staff still experienced issues with reliability. CORTRAK was not used at the Trust where the reference event happened.

5.3.1 The investigation found there is ongoing national research to find a more reliable method to check NG tube placement.

5.3.2 There have been many studies and review articles which suggest a promising method of NG tube confirmation technology. However, there are both advantages and limitations to the methods considered. These have been described in the literature (Fan et al, 2017).

5.3.3 Medical Research Council funding had been awarded to develop a solution to tackle the safety issue of incorrect NG tube placement. The Medical Research Council funded work aims to develop, build, and test a new portable, sensor-based device known as NGSure® to give an accurate check of NG tube position. NG-Sure® works using sensor technology, measuring gases or chemicals at the end of the NG tube, known as volatile organic compounds, to create ‘smell fingerprints’, in addition to a pH reading. These fingerprints differ depending upon where the NG tube is situated (stomach, oesophagus, or lungs). The project commenced in January 2019 and was anticipated to take three years.

5.3.4 In addition to the research above, the investigation was advised of a system that is available for use via NHS supply chain called NGPOD®. The NGPOD® system consists of a single-use fibre optic sensor (NGPOD® sensor) and a small handheld light source and detector (NGPOD®). The fibre optic sensor is fully inserted down a placed NG tube. The sensor is then connected to the handheld NGPOD® and a test button is pressed. The NGPOD® returns a green tick or a red cross based on the pH level at the tip of the sensor. The sensor can then be removed from the NG tube and discarded. A multi-site study began in May 2019, following previous research trials, and it is expected that an evaluation report will be published in spring 2021. The study includes NG tube placement checks made after the first insertion of the NG tube, as well as repeat testing immediately before the administration of liquids.

5.3.5 Anderson et al (2016) noted that patients on acid-suppressing medication never had acidic gastric aspirates which made pH tests falsely negative. The researchers developed and validated a lipase (stomach enzyme) test that was compatible with non-acidic gastric aspirates to tackle the pH testing issue. The study showed that the sensitivity of the lipase test (sensitivity 97.2%) was significantly better than pH (sensitivity 65.7%). It concluded that the lipase test showed a true positive when stomach aspirates were not acidic and was significantly more accurate than pH testing (Anderson et al, 2016). The researchers’ intention is to develop the lipase test prototype and create a more viable daily NG tube position test for patients on acid suppression both in hospital and in the community.

5.3.6 The investigation spoke with the research team at Imperial College Hospital and found that lipase testing was going through clinical trials, including lipase testing with paediatric patients. The research team was also exploring different ways to present the lipase results to avoid ambiguity in readings.

5.3.7 In addition to the above, there are 15 Academic Health Science Networks (AHSNs) across England. These were established by NHS England in 2013 and relicensed from April 2018 to operate as the innovation arm of the NHS to spread innovative ideas and technologies at pace and scale. Their innovation exchange offers access to business expertise from AHSN teams across the country. The innovation exchange has not, as yet, been asked to consider NG tube safety as one of its priorities.

5.3.8 The investigation considered there was a need to co-ordinate work to understand the current evidence base and any further research needs for safety solutions to confirm NG tube placement. This would then enable the system to commission larger-scale research based upon the evidence identified to support the implementation, authorisation, and national adoption of safety solutions to confirm NG tube placement. It was apparent during discussions with NHS England and NHS Improvement and the Department of Health and Social Care, that there is a significant gap within the current NHS infrastructure in the assessment of the current evidence base and identifying research needs to support improvements in patient safety. NHS England and NHS Improvement and Department of Health and Social Care expressed an intent to identify critical research needs and therefore HSIB makes the following safety recommendation:

HSIB makes the following safety recommendation

The Medicines and Healthcare products Regulation Agency Yellow Card scheme

5.4.1 The Medicines and Healthcare products Regulatory Agency (MHRA) is the ‘Competent Authority’ and also the ‘Designating Authority’ for medical devices for the UK. The MHRA administers and enforces the law on medicines and medical devices in the UK and is responsible for their safety.

5.4.2 The MHRA’s role is to protect and promote public health and patient safety by ensuring that medicines and medical devices meet appropriate standards of safety, quality, and efficacy.

5.4.3 The MHRA runs the Yellow Card scheme (Medicines and Healthcare products Regulatory Agency, 2020). This is the system used in England for collecting and monitoring information on suspected safety concerns involving medicines and medical devices. Reporting is voluntary by health professionals and/or patients.

5.4.4 Adverse incidents involving any medical device or in vitro diagnostic [10] medical device should be reported to MHRA via the Yellow Card scheme. A medical device may not carry a CE mark, for example if it is counterfeit, and this would still be reportable. pH testing strips for human gastric aspirate are an example of a medical device.

5.4.5 The investigation was made aware that the incident involving Fabian’s mis-placed NG tube had not been reported to the MHRA.

5.4.6 It is important for people to report problems they have experienced with medicines or medical devices as the information is used to identify issues which might not have been previously known about. The MHRA will review the product if necessary and take action to minimise risk and maximise benefit to patients.

5.4.7 It is understood that the MHRA has a data sharing agreement with NHS England and NHS Improvement, to share incident reports uploaded to the National Reporting and Learning System (NRLS) related to medicines or medical devices. The MHRA advised that it was not aware of individual details of reported incidents related to pH testing strips and Never Events involving misplaced NG tubes. The investigation was advised however that the MHRA was aware of the thematic issue of Never Events related to misplaced NG tubes.

5.4.8 A previous HSIB investigation, ‘Design and safe use of portable oxygen systems’ (Healthcare Safety Investigation Branch, 2018), found that the number of reports made through the Yellow Card scheme regarding issues with portable oxygen systems was significantly lower than the number of incidents being reported through NRLS on the same topic.

5.4.9 The purpose of the Yellow Card scheme is to provide an early warning that the safety of a product may require further investigation.

5.4.10 The MHRA was responsive to the investigation’s concerns regarding variability in pH testing strips despite not being aware of issues with pH strips for human gastric aspirate. It contacted three manufacturers listed on the NHS Supply Chain catalogue and asked:

5.4.11 Feedback was received which unanimously stated only to use the pH strips with the compatible container colour chart and that the key was education and posters to ensure correct use. The manufacturers recognised 77 that as the pH indicator colour strips vary, it would be incorrect to compare one manufacturer’s pH testing strip against another manufacturer’s colour reference chart. Mitigations to minimise risks included that users should ensure that the strips are used with the corresponding colour chart on the container. In addition, manufacturers provide educational posters and training.

5.4.12 After consulting with different manufacturers of testing strips, the MHRA concluded that:

5.4.13 Given the above comment regarding there being very little in terms of the product itself that can be changed, there will remain a risk to patient safety as the variability will continue and the associated risks are placed onto the user.

5.4.14 NHS England and NHS Improvement informed the investigation that there are data sharing agreements in place with national bodies such as the MHRA to enable sharing of information from NRLS. This covers all incident data relating to medical devices and additional bespoke reports can be created on request. However, there does not appear to be a shared system-wide knowledge of the reported incidents related to confirmation of NG tube placement, for example, pH testing strips, because of limitations in interoperability of national reporting systems being used by the NHS.

5.4.15 The investigation was told that applications for data sharing from other bodies with safety responsibilities are welcomed by NHS England and NHS Improvement, but the effectiveness of data sharing is reliant on other bodies having the resources to review the incidents they receive. The risks of not having a reliable process to alert and communicate safety concerns between national bodies was recently expressed in the report of the Independent Medicines and Medical Devices Safety Review (Cumberlege, 2020).

HSIB makes the following safety observation

HSIB makes the following safety recommendation

CE marking approval

5.4.16 A CE mark is a baseline standard for placement on the EU market. pH strips do not need a Notified Body [11] to approve them to get a CE mark. The manufacturer can self-certify and give the product a CE mark once they are satisfied with their own data. This is allowable under the current EU Invitro Diagnostic Directive (IVD). Under the new Invitro Diagnostic Regulation (IVDR) taking force in the EU in May 2022, there will be a reclassification of devices according to risk under the new IVDR regulation (EU) 2017/746 (British Standards Institution, 2020a). pH strips for human gastric aspirate will become a class B device (British Standards Institution, 2020b). This will mean manufacturers will need a Notified Body approval to obtain a CE mark. However, as the UK has left the EU, the UK (MHRA and Office for Life Sciences (OLS)) has decided not to adopt the new IVDR and will continue to operate an IVD type approval. This means that pH strips will not have the same scrutiny in the UK as they will have in the EU as they will continue to be self-declared by the manufacturers.

5.4.17 Currently, if there is a serious patient safety incident involving medical devices to confirm NG tube placement, for example pH testing strips, the incident should be reported via the Yellow Card scheme. The information would be shared with and registered on the European database Eudamed. However, after the UK has completed the transition in January 2021 from the EU, the MHRA will no longer have access to Eudamed data. This means that, in the post-transition regulatory environment, the MHRA will only know about such cases occurring within the UK.

HSIB makes the following safety observation

Procurement

5.4.18 pH testing strips for human gastric aspirate are currently procured for trusts by NHS Supply Chain (NHSSC) and made available via the NHSSC catalogue. However, not all trusts purchase via NHSCC and NHS trusts can purchase directly from manufacturers. Independent hospitals providing NHS-funded care do not have access to NHSSC. There are multiple manufacturers and variability in design of strips.

5.4.19 The concerns regarding the variability in pH testing strips was shared with NHSSC. The investigation was made aware of plans to bring the systemwide intelligence together to inform future procurement plans and specification development along with system-level response to issues. It was anticipated that there would be reduced variance in patient outcomes due to standardisation of product features and reduced staff training requirements as product categories would meet defined user requirements.

5.4.20 The investigation was told that NG tube confirmation using standardised pH paper could be an area of focus to develop using essential specifications.

5.4.21 The investigation was informed that this specification approach would drive improving standards and support innovation within the clinical manufacturing industry. NHSSC told the investigation that it would review the efficacy of devices used in practice, supported by intelligence from clinical partners and other agencies. This would support mitigation of risk to patients and users, for example by suspension or removal of a product from the list of products it will supply with appropriate alternatives put into place.

HSIB makes the following safety recommendation

Use of electronic systems

5.5.1 The investigation spoke with two trusts that were in the early stages of implementing electronic pathways to aid NG tube policy use. The electronic system offered a series of prompts and checklist items which clinicians could complete while the NG tube was being inserted, or once the NG tube was inserted. The NG tube electronic system would then serve as a checklist to ensure certain tasks in the process had been completed.

5.5.2 It was anticipated that the system would offer several benefits:

• There is an audit trail of the NG tube insertion.
• If aspirate is unable to be obtained or the pH is outside the ‘safe range’ a flowchart of actions to take is presented to the clinician.
• The system will alert clinicians if the tube has moved more than 2cm from the original sited tube length.
• X-rays can be viewed electronically and so can be accessed throughout the hospital. This means clinicians can approve X-rays remotely without having to be with the patient, enabling NG feeding to commence as soon as possible. The Royal College of Radiologists highlights that there is the risk of sub-optimal conditions for clinical evaluation due to environmental conditions and the device X-rays may be viewed on (The Royal College of Radiologists, 2019a).
• The system mandates commenting on the four criteria for interpreting the position of the NG tube on X-ray.
• There are prompts to alert if the NG tube has expired or is expiring soon.
• It provides an opportunity to capture and analyse NG tube data to provide greater oversight and intelligence around NG tube insertion and confirmation of placement.

5.5.3 Of the two trusts that were adopting the electronic system, one was about to roll out the system and the other had piloted the system for six months. They had launched the system in several wards. Neither of the trusts had data on the impact and use of the system. They reported that evaluation was key and were looking to evaluate the system in future.

Using trained experts

The Nasogastric Special Interest Group (NG-SIG) of the British Association of Parenteral and Enteral Nutrition (BAPEN) published a position paper on NG safety (Jones, 2020). The position paper highlighted 18 findings and included recommendations. It concluded that the ‘perception of nasogastric feeding tube insertion as a “simple” procedure must be changed to that of a “complex” and dangerous procedure and limited to properly trained and competent healthcare professionals’. The position paper stated:

5.5.4 Discussion with the research team at Imperial College Hospital also suggested that limiting the responsibility of insertion and confirmation of NG tube placement to a limited cohort of ‘experts’ may be beneficial. The research team commented that current methods had huge potential for error, particularly for pH testing. In a simulated study, Borsci et al (2017) found a 11.15% error rate in participants’ readings of pH strips, with important implications for decision making regarding NG tube placement. (Borsci et al, 2017). The team suggested that there may not currently be experts in pH reading and NG confirmation of placement and that it would be unrealistic to retrain the whole health service in what is an unsafe and error-prone procedure. Like BAPEN, they also suggested regularly assessing the competency of experts.

5.5.5 The Imperial College Hospital team stated that using specifically trained experts would need to be trialled and any training would need to be defined, developed, and tested using a human factors approach prior to any widespread implementation.

The role of the radiographer to improve patient safety related to NG feeding in adults

5.5.6 According to national guidance (NHS Improvement, 2016b), interpretation of X-rays would typically be done by medical staff or by radiologists. Radiologists are doctors who are specially trained to interpret diagnostics images such as X-rays, MRI and CT scans. Radiologists also perform interventional procedures, such as angiograms or biopsies (Royal College of Radiologists, n.d.).

5.5.7 A radiographer is a registered healthcare professional and they undertake a broad portfolio of either diagnostic examinations or radiotherapy procedures (The Society and College of Radiographers, n.d.).

5.5.8 The Quality standard for Imaging (Royal College of Radiologists, 2019b) has a requirement to ensure communication of X-ray reports within specified timescales and that there are systems in place to manage unexpected findings and potential medical emergencies.

5.5.9 NG tube removal by radiographers has been trialled in a single site NHS trust with positive results (Law and Kelly, 2011). This research was used as a basis for a large multi-site teaching trust pilot.

5.5.10 The investigation visited this large multi-site teaching hospital which had expanded the role of the radiographer to contribute to risk reduction regarding feeding through misplaced NG tubes. The trust published its results (Roe et al, 2017). Two main roles were developed for radiographers: first, consistently commenting on the tube position on the image; and second, taking a defined role in NG tube management by removing misplaced tubes (Roe et al, 2019).

5.5.11 The initial trial implemented a system to determine the accuracy of radiographer comments against the standard of radiologist reports to see whether the role of the radiographer helped reduce the number of Never Events. In addition, as part of its research the trust considered radiographer confidence in undertaking their new role and their evaluation of patient benefit from this system of working. It concluded that after focused training, the role of a radiographer in NG tube confirmation by X-ray was a safe, effective, sustainable and workable solution to image misinterpretation issues relating to NG tube Never Events. It was suggested the system should be considered for wider implementation in healthcare (Roe et al, 2017).

5.5.12 The radiographer will check any X-ray for NG tube position, even if the request is not specifically for NG tube confirmation of placement. They check that the NG tube is in position and are empowered to act if not. The trust had examples of how radiographers flagged a tube that may have become displaced on a chest X-ray that had been carried out for other reasons before any harm occurred to the patient.

5.5.13 The studies using radiographers suggest they are guided by rigidly following a protocol and this leads them to confirming if the tube is in the correct place (or is not and should be removed). This is considered to add an additional safety net or a potential barrier to X-ray misinterpretation by a clinician because another trained expert is questioning the position before the doctor.

While not directly relevant to the reference event, the following observation and recommendation has been made given the continued risk of NG tube Never Events following incorrect X-ray interpretation:

HSIB makes the following safety recommendation

HSIB makes the following safety observations

6.1.1 Coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus (World Health Organization, 2020a). The World Health Organization (WHO) recently concluded that, based on the current evidence, transmission of COVID-19 is primarily through respiratory droplets and contact (World Health Organization, 2020b).

6.1.2 Guidance has been updated to reflect pandemic evolution and the changing level of risk of exposure to COVID-19 in healthcare settings in the UK. There was believed to be an increased risk for healthcare staff subjected to repeated risk of contact and droplet transmission during their daily work.

6.1.3 The COVID-19 pandemic has posed several challenges for the national healthcare system. This has required the reconfiguration of environments, repurposing of equipment, acquisition of new equipment and cross-skilling of staff.

6.1.4 COVID-19 is a complex disease which, in the early stages, primarily affects the respiratory system. This leads to a pneumonia-like illness. It has been suggested that confirming nasogastric (NG) tube position during COVID-19 has been more challenging than usual (British Association of Parenteral and Enteral Nutrition, National Nutritional Nurses Group, Intensive Care Medicine, Intensive Care Society, Royal College of Anaesthetists, 2020).

6.2.1 National healthcare organisations have issued several COVID-19 related patient safety alerts. NHS England and NHS Improvement produced updates on issues related to COVID-19 and the impact on patient safety. The updates were pulled together to disseminate key information that trusts’ patient safety heads might need to know but could otherwise miss. They were not intended for general circulation within organisations.

6.2.2 Special considerations were agreed for confirming NG tube placement for COVID-19 patients. In summary, professional bodies for nutrition, anaesthetics and intensive care produced an aidememoire, entitled ‘Nasogastric tube (NGT) placement checks before first use’, to help prevent NG tube Never Events in critical care settings during the COVID-19 response (British Association of Parenteral and Enteral Nutrition, National Nutritional Nurses Group, Intensive Care Medicine, Intensive Care Society, Royal College of Anaesthetists, 2020).

6.2.3 The aide-memoire was not designed to replace existing, established NHS Improvement compliant practice of NG tube confirmation for areas where there had been no significant change to staffing. However, it was considered that staff returning to practice, or redeployed to critical care environments, including in Nightingale hospitals, would be helped by reminders of established safety steps in a form that can be used for all critical care patients, rather than requiring different processes for different patients.

6.2.4 The advice in the aide-memoire was to:

6.2.5 The investigation heard from people and organisations who said while the guidance was issued with good intent, it did not follow the normal channels for dissemination and caused confusion for organisations.

6.2.6 Staff told the investigation that the aide-memoire caused some confusion within trusts as those with a stable and established workforce used to using pH testing as first-line confirmation could continue to do so, whereas those in unfamiliar environments should be using X-ray. The investigation heard from trusts that stated they continued to use their existing local policy rather than suddenly adopting a new process.

6.3.1 The coronavirus outbreak was a rapidly evolving situation and the investigation has considered this in relation to NG tube insertion and safe confirmation of NG tube position in adults in acute hospitals.

6.3.2 It was considered that there were increased risks associated with patients who had been put into a prone position (lying on their front) for clinical reasons, as there is an increased risk of regurgitation of gastric contents into the oesophagus and aspiration into the lungs which will render pH checks less reliable.

6.3.3 The NG tube safety position paper reported on the COVID-19 crisis and the concerns in relation to NG tube position confirmation during the pandemic (British Association of Parenteral and Enteral Nutrition, 2020).

6.3.4 Staff told the investigation that in some of their trusts, there was a reported increase in requests for X-rays. However, there were concerns that X-rays remain a risk when used to confirm NG tube placement.

6.3.5 X-ray images associated with patients with a COVID-19 infection were also more difficult to interpret because of the ‘ground glass’ appearance – meaning that a hazy lung opacity shows up on imaging.

6.3.6 Staff told the investigation that they were working in unfamiliar environments and therefore not used to working with patients with NG tubes. There were reported concerns that the education and competency assessments were rushed.

6.4.1 There were eight Never Events reported on the Strategic Executive Information System (StEIS) from March to July 2020. A qualitative analysis of these events was performed.

6.4.2 In two of the Never Event reports, the nursing team was not able to get any aspirates for pH checks. In addition, the tube position was not being confirmed after movement or when there was clinical concern. For example, if there is resistance or aspirate cannot be obtained. These scenarios are common and link back to the investigation findings that these do not prompt the staff member to seek further confirmation.

6.4.3 It remains unclear from a review of the reports whether pH is always used as the first-line check for NG tube placement.

6.4.4 Of the eight Never Event reports, misinterpretation of the X-ray was a factor in three reports. The reports provided additional evidence that the fourstage X-ray confirmation (NHS Improvement, 2016b) was not being used and the inference from the summary details is that ‘tip below diaphragm=fine’. Guidance already reminds the healthcare professional that if the X-ray is not clear enough to view the ‘four criteria’, to seek radiology advice. Simply looking for ‘tip below diaphragm’ is not enough as misinterpretation using this technique is the cause of most fatalities from feeding through misplaced tubes.

6.4.5 There are examples of where a radiographer informed a member of staff that an NG tube was in the wrong place, but the tube was not removed promptly and feeding was commenced.

6.4.6 It is possible that imaging will only be requested if considered clinically urgent because donning and doffing of personal protective equipment (PPE) by radiographers as they move between clinical areas, was reported as problematic. In one reported instance the X-ray confirmation of NG tube positioning was considered non-urgent, so the imaging did not take place in a timely way.

6.4.7 In one of the local StEIS investigations it was reported that low oxygen saturations could have been assumed to be associated with COVID-19 rather than inadvertent administration of NG feed into the lungs or the pleural cavity. This is consistent with concerns raised by the British Association of Parenteral and Enteral Nutrition (BAPEN).

6.4.8 It was reported by one trust via StEIS that the capacity to initiate investigations into misplaced NG tubes was limited and it was considered more important to protect the psychological welfare of staff. Access to clinical notes in COVID-19 areas was restricted preventing timely investigation and reflected pressures on the system at that time.

6.5.1 Certain work environments and procedures convey a higher risk of COVID-19 transmission. Procedures in medical and patient care that result in the production of airborne particles (aerosols), known as aerosol generating procedures (AGPs), present a risk of aerosolised transmission. The highest risk of transmission of respiratory viruses occurs during AGPs of the respiratory tract. The use of enhanced respiratory protective equipment is indicated for healthcare professionals performing or assisting in such procedures.

6.5.2 Guidance was produced with the intention of setting out clear and actionable recommendations on the use of PPE, as part of safe systems of working, for health and social care workers relative to their day-to-day work.

6.5.3 The investigation was made aware of letters written by the President of BAPEN to the Secretary of State and Public Health England requesting the redefinition of NG tube insertion as an AGP. At time of writing, this situation remains unresolved.

6.5.4 Social media coverage suggested there was significant debate about whether NG tube insertion should be classed as an AGP. There appeared to be inconsistency in trusts’ approaches, with some continuing with ‘it’s not an AGP’ and others considering it an AGP that required the donning of full PPE. Staff told the investigation that a pragmatic approach was taken, for example, “if you are worried your patient is going to cough excessively then it is entirely reasonable to wear full gown, visor etc”. It was also reported that over time, staff became more comfortable with basic PPE only.

6.6.1 The investigation was made aware that the pandemic had had a direct impact on research discussed in section 5 of this report. One multisite research study was considered ‘non-essential’ and therefore paused. It was reported that there was a risk of NG aspirates being transported from the hospital to a laboratory, and there would be a risk to the person analysing it if a sample were from a patient with COVID-19. Another piece of research referred to in section 5 did continue.