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Complications – the unforeseeable…or merely the unforeseen?

2006; Wiley; Volume: 47; Issue: 12 Linguagem: Inglês

10.1111/j.1748-5827.2006.00276.x

1748-5827

D. M. Anderson,

Cardiac, Anesthesia and Surgical Outcomes

“I understand that all anaesthetic techniques, investigative and surgical procedures potentially involve some unforeseen risk to the animal”. As you watch your client sign the consent form, do you reflect on how much we actually know about these ‘unforeseen risks’? Are they risks we would be willing to accept for our own pets, ourselves or for our children? This issue of the Journal of Small Animal Practice has a number of articles reporting complications associated with surgery. We all know that complications are not uncommon, and yet, these reports are memorable for their scarcity. We explain to owners the risks that we have heard or read about – but do we really have any idea of how likely these complications are? More importantly, do we know how reported complication rates relate to what happens in our own clinics? Surely, as a profession we have a moral obligation to bring these issues to the forefront and respond to the call for realistic reports on the limitations of our procedures rather than our success rates. What is the difference between acceptable and foreseeable complications and those that are unforeseen and/or unexpected? Take an example: A dog presents with a functional obstruction due to abdominal adhesions and chronic septic peritonitis following enterectomy. Even after surgery, the prognosis is still guarded for this dog. Clearly this is an unacceptable outcome of an uncomplicated enterectomy, but not exactly unforeseen – if the repair is insufficient, the gut will leak and cause these complications. The pathology of the process is entirely predictable, although it was unexpected. If it was foreseeable, surely we should advise owners of all potential consequences – even those that we do not expect? If we did tell owners exactly what the word ‘risk’ means, would they then ever have the courage to ask us to do anything? At what point do we rest easy that we have explained the risks in the knowledge that we know what those risks are in our own hands. It takes some courage to set down in print the complications that you come across in your own clinic. Perhaps the complication rate reported by your centre compares unfavourably to the current literature. Whilst this may be perceived as reflecting problems in your clinic, with your clinicians, or even in your clinic population, it is more likely a consequence of inadequate reporting of complications in the veterinary literature. Tattersall and others (2006) report a retrospective study of complications associated with thoracotomy over a period of 5 years. Whilst reporting these complications is to be commended, it would have been very valuable to explore further by evaluating the effects of individual groups of surgeons on complication rates. It would not be unreasonable to expect that there might be some variation in success rates according to the level of skill of the surgeon involved. Grouping the surgeons into ‘residents’ (who may be in only their first second or third year of study), ‘Board eligible’ (who have completed a residency and are awaiting Board examination) or ‘Board certified’ (those who should be expected to have a fairly uniform level of skill) and comparing complication rates for each group separately might have added value to this publication by demonstrating the origin of these complications. Perhaps in-depth studies of this nature produce some uncomfortable results for which the profession is not yet prepared. One of the problems with veterinary complication data is that much of it is derived from large studies from specialist centres that have the self confidence to report issues knowing that their reputation will not be threatened. We remain blind to what happens in other centres where staff have less experience and see fewer cases - do they have similar complication rates; are they higher (because staff have less experience); or lower because they have more time to spend on the cases? Individual vets require data to allow them to decide if the reported complication rates are transferable into their consulting room as they advise clients before consent is given. In a previous issue of this journal Shales and others (2005) reported a significantly higher than previously accepted mortality rate in gut biopsy patients. The cases described had been seen in a referral centre – is this higher mortality rate transferable to the general practice setting? On the one hand, you might expect the sterile technique, surgical skill and anaesthetic management to be better in the referral centre - but in general practice might the average patient be less severely affected, and the mortality rate lower? Although the study tried to address this uncertainty, without a controlled prospective study there is still no way of knowing what potential complication rate you should quote to the owner of animal being admitted for a gut biopsy in practice. Perhaps we are also selective about informing our clients of potential risks. There is one retrospective study on lower limb iatrogenic bandage injuries in the veterinary literature (Anderson and White 2000) – which only had eleven cases. I cannot believe that bandage injuries are that rare, but do owners get warned of the possibility of a simple bandage resulting in the loss of the limb – or worse, the death of their animal? Probably not! Papadopoulis and Degna (2006) report two cases in depth and refer to a third case of urethral obstruction secondary to a triple pelvic osteotomy (TPO) procedure. Orthopaedic surgeons may read this report and either nod sagely or sneer – but it took courage and responsibility to report these cases. The authors display an element of frustration with the veterinary fraternity in the sentence: ‘There is little other published information about this complication and most authors do not mention post-operative dysuria as a significant complication’. I am inclined to agree with their frustration - that this cannot be the first time the complication has been noticed, but is the first time it has been adequately reported. Their later conclusion: ‘Personal experience with the complications of TPO surgery has shown that post operative dysuria is as relevant as premature screw loosening…’ is also most pertinent. Specialists have much to offer beyond their years with a nose in a book – a wealth of clinical experience with complex procedures, difficult cases and a variety of complications, but it is only by publishing this data that the information can be critically appraised and updated. Sir Karl Popper, a twentieth century philosopher, stated that ‘while an unlimited number of verifications are needed to confirm a hypothesis, only one is required to refute it’. Thus hypotheses should be tested to refute rather than prove and we can never absolutely confirm any premise. This is easily applied to basic sciences where the technique of disproving hypotheses is standard. However, as clinicians we do not approach our clinical reporting in the same rigorous way. Admittedly, scientific method does not rest easy with the chaos of clinical material and we are fortunate if we have sufficient numbers of cases to test the data statistically. However, applying Popper’s philosophy to our clinical practice, remembering that every premise is affected by its consequences (whether or not it goes wrong) therefore any premise, however well intentioned, has unforeseeable and unintended consequences. So the next time the unforeseeable, unintended or unexpected occurs in your clinic, consider it the closest clinicians get to science, and publish it. Davina Anderson graduated from Cambridge University in 1989 and spent two years in mixed practice before taking up an internship at the RVC. She later returned to Cambridge and completed a PhD in cultured skin grafts before starting a residency in small animal surgery. She became a Diplomate of the European College of Veterinary Surgery in 2000 and gained the RCVS Diploma in Small Animal Surgery (Soft Tissue) in 2003. She worked with Dick White as Lecturer in Soft Tissue Surgery at Cambridge University until 2005 when she moved to Hampshire. She now works in her own multidisciplinary specialist referral practice in Winchester and is a RCVS Recognised Specialist in Small Animal Surgery (Soft Tissue).