The Healthcare Safety Investigation Branch (HSIB) has today published an investigation report relating to a never event, the administering of a wrong site nerve block. 

The patient, Mr Awcock, is a 69-year-old man who attended a specialist orthopaedic treatment centre at an acute NHS Trust for elective surgery on his right ankle. This included a plan to administer either two local anaesthetic nerve blocks (injections to block pain in specific regions of the body), and a general anaesthetic as part of the operation. Following administration of the local anaesthetic, the operating department practitioner identified the second nerve block had been carried out on the left leg in error. Consequently, Mr Awcock was unable to receive the second nerve block to his right leg (the correct leg) due to the risk of anaesthetic toxicity.

HSIB's investigation centred on how the reference event error occurred and what recommendations could be made to reduce the risk of a similar event happening again. The investigation considered the contributory factors to the patient receiving the anaesthetic nerve block to the wrong leg including a review of the Stop Before You Block (SBYB) process and its efficacy in reducing the risk of a wrong site block. The investigation team observed similar anaesthetic procedures in several NHS Trusts and witnessed variations in practice and compliance with the national and local guidance.   

The investigation team worked collaboratively with organisations including the Royal College of Anaesthetists, NHS Improvement and the Department of Health and Social Care. The investigation and final report was based on reviewing existing data, observations in operating theatres, interviews and clinical subject matter and human factors expertise.  The report makes two safety recommendations, and one safety observation to support staff and to improve patient safety. The report highlights the importance of ensuring there is a strong evidential basis and human factors based approach to the development of national patient safety initiatives.  

Chief investigator, Keith Conradi, whose experience includes six years as the chief investigator of the Air Accident Investigation Branch, said;  

Our report into the administering of a wrong site nerve block is the culmination of many months of rigorous and independent investigation. Our investigation team worked closely with those involved in the incident, as well as relevant organisations and subject matter experts. Our independence allows us to make public safety recommendations to the healthcare sector. In publishing this report, we have made safety recommendations to the Royal College of Anaesthetists who must respond within 90 days on how they will action the recommendations to improve patient safety. We will publish their response on our website."


Notes to editors:

The patient has agreed to be named in this report. He would prefer to not undertake any further media involvement.

This report is the third safety investigation report published by HSIB. There will be up to thirty investigations undertaken each year with safety recommendations published to mostly national bodies to ensure systemic learning that does not apportion blame or liability.

The Healthcare Safety Investigation Branch’s role is to investigate safety incidents for the sole purpose of learning and improving patient safety across the healthcare sector without attributing blame or liability. The intention is to build on HSIB’s work and strengthen its independence – via legislation currently at draft Bill stage – which would see the creation of a statutory Health Safety Investigations Body, independent of the NHS and arm’s length from Government. Its creation is inspired by the airline industry, where a learning culture has led to significant improvements in safety.

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