Wrong site surgery is the second most common US sentinel event. It is 4.5 times more likely than a transfusion error and 8 times more likely than an infection related event [1]. A pilot study in 18 trusts on behalf of the National Patient Safety Agency (NPSA) found 15 incidents. Previous work has shown that only the most serious cases are reported by doctors. Extrapolating these figures to the UK as a whole suggests more than 400 cases per annum in the UK alone [2].

A review of claims brought to the Medical Defence Union in the UK found that 39% of cases related to surgery on the wrong side and 61% to the patient having the wrong procedure.

Within the specialities where wrong sided procedures are a potential problem the total value of reported claims in the CNST scheme is £2.5 billion. Clearly a large amount of this total does not relate to wrong site procedure claims but where it does the likelihood of defence is very small. The Physician Insurers Association of America (PIAA) reported a settlement rate of 84%, much higher than the normal amount [3]. Claims can be very high, even as long ago as 1995 a Florida patient was awarded $1.2 after amputation of the wrong foot.

The error is found in all areas of medical practice where procedures occur, predominantly in the surgical specialities but also in accident and emergency, medicine and radiology. Amongst surgeons, data suggests that orthopaedic surgeons are the most likely to make the mistake, the PIAA figures show that based on reported events 1 in 4 orthopaedic surgeons will perform wrong site surgery during their career.

The American Academy of Orthopaedic Surgeons launched the 'Sign the Site' campaign in 1998. This urged surgeons to sign the actual site of surgery. Seventy percent of surgeons felt that this was a good idea. Only 12 months later, despite 70% still supporting the idea only 40% were still signing. This reinforces the fact that voluntary schemes which rely on a single individual are unlikely to work [4].

A second interesting point from the AAOS study is that only 70% of surgeons felt that marking was a good idea. This prompted a UK study of the attitudes of UK Urologists to patient marking [5]. In this study 75% of surgeons supported pre-operative marking of patients. Twenty-five percent were opposed to marking, feeling that nothing should dilute the responsibility of the operating surgeon. Even amongst those who agreed with marking, many were willing to delegate this important procedure to the most junior member of the surgical team. The research also found a wide variation in the nature of the mark used. Although arrows were the most popular other symbols such as crosses were used by some individuals, this of course leaves a great deal ofscope for confusion.

References

[1] US sentinel events stats as of December 2004 http://www.jcaho.org/accredited+organizations/ambulatory+care/sentinel+events/sentinel+event+statistics.htm

[2] http://www.npsa.nhs.uk/display?contentId=3549

[3] Medical Mutual Insurers http://www.medicalmutual.com/risk/tips/HCF/16.htm

[4]Did wrong-site Surgery Remedy Work? http://www.rmf.harvard.edu/publications/resource/feb1999news/article2/body.html

[5] To Mark or Not To Mark. Henley MJ, Chilton CP. Unpublished.