Behind The Medical Headlines

KEYHOLE SURGERY FOR HERNIA – THE KEY IS GOOD TRAINING AND HOLE IS WHERE THE SURGEON AND POSSIBLY PATIENT MAY FIND THEMSELVES WHEN POORLY TRAINED

• Mr S Nixon, Consultant Surgeon, Edinburgh, Scotland

Summary

In recent years, keyhole surgery techniques have been developed for a range of surgical procedures. However, it has been suggested that keyhole surgery for hernia carries an increased risk of complications over traditional, open, surgery. Mr Steve Nixon reviews the evidence

Declaration of interests: No conflict of interests declared

By now you might believe that surgeons must have come close to the Halstead dream of ‘a perfectly safe cure for rupture’. After all, inguinal hernia is the most common surgical condition to affect men with almost 1,000 operations performed annually per 1,000,000 of the population in the UK. Surely, practice makes perfect. Over 100 years ago Bassini described his sutured repair which was a milestone in hernia surgery. More than 25 years now have passed since Lichtenstein developed the tension free mesh repair using polypropylene claiming rapid recovery and a 99% chance of permanent cure. This is today’s gold standard operation in the Western world. As so often seen in surgery, the early promise of an operation promoted by the specialist centre fails to materialise when rolled out across the surgical community. A recent, large scale audit across Scotland¹ gathered data on over 4,500 procedures performed during 1998–99 and found that open mesh repair is the most common operation by far. However, it also showed that 80% of patients had in-patient rather than day case surgery, 10% of patients required post operative nursing care to deal with complications and almost one in ten patients required re-do surgery where a previous operation had failed to produce permanent cure and the hernia had recurred. Put simply, in routine practice surgeons use too much resource, have too many complications and fail to cure the patient in over 10% of cases. The more intensive follow-up used in the Medical Research Council (MRC) hernia trial² showed a complication rate of 30% and 40% for laparoscopic and open surgery respectively. Increasing concern is also being expressed about the complication of long-term groin pain, sometimes extreme and often untreatable, associated with mesh repair in particular but common to all types of hernia surgery. Most reports suggest that groin pain is more common and more severe after open surgery when the mesh is placed in direct contact with the ilio-inguinal nerve. Softer and more pliable meshes may reduce this problem but are unlikely to solve it completely. It is not surprising that surgeons are still actively looking for alternative approaches to manage this common condition.

Over the past decade, attention had turned to the laparoscopic approach based on the concept that minimally invasive surgery will reduce complications and accelerate recovery. There are two standard laparoscopic approaches either through the peritoneal cavity (TAPP) or via the extraperitoneum (TEP). The modern approach to an inguinal hernia is directly through the skin and opening part of the abdominal wall musculature to enter the inguinal canal, in effect further damaging the muscular structures that are already weakened. The TEP laparoscopic approach is ‘preperitoneal’ whereby the surgeon makes an incision well away from the hernia and dissects through all layers of the abdominal wall to enter a space between the muscles and peritoneum. It is relatively simply to develop this space as no major vessels or any nerves pass across it. The hernia is then pulled back into the abdomen and the muscle weakness then strengthened from within. The concept of preperitoneal surgery is not new and the famous surgeon Lloyd Nyhus, a strong advocate of this approach, attributed its first description to Professor Sir Thomas Annandale of Edinburgh University reporting in the Edinburgh Medical Journal of 1876. This was more than a decade before Bassini reported what was to become the gold standard technique for almost 100 years. The modern day laparoscopic TEP operation merely uses minimal invasive surgical techniques to exploit the Annandale approach. If TEP surgery were to become the new gold standard then Annandale might replace Bassini as the father figure of hernia surgery.³

In truth there is a paucity of scientific evidence with which to compare these approaches but there is a general view that the TEP approach is to be preferred, as it is perceived to be associated with reduced risk of injury to bowel, bladder and iliac vessels. There has been a torrent of randomised controlled clinic trials (RCTs) of variable quality and size followed by the inevitable meta-analyses. Perhaps the least biased of these was reported by the National Institute of Clinical Excellence (NICE) in 2001.⁴ The National Institute of Clinical Excellence examined over 40 RCTs and reported that laparoscopic surgery was indeed associated with less pain and faster recovery, but also with increased cost and longer operating times. They concluded that for first-time hernia surgery, the open mesh repair remained the operation of choice but the laparoscopic approach may be considered for recurrent and bilateral cases. The National Institute of Clinical Excellence is currently revisiting this area and will report again in August 2004, accepting that their initial study was based on data gathered during the learning curve of laparoscopic surgery and also that longer term follow-up data was required to complete the picture.

The recent media coverage which gave rise to this article presented a rather bold and bald analysis of a paper from Utah, US, which reported a randomised trial of open versus laparoscopic hernia trial with 834 and 862 patients in each arm of the study and two years follow-up.⁵ The open group had a complication rate of 33% and recurrence of 5% (rather higher than most other reports), but the laparoscopic group had a complication rate of 39% and recurrence rate of 10% (very high compared with other reports). They concluded that ‘men with a hernia that has never been repaired before should undergo an open repair’ exactly the same conclusion made by NICE three years previously.

Buried deeply within the text is an analysis of recurrence rate by experience. Surgeons who have performed more than 250 operations had similar recurrence rates of 5·1% and 4·1% respectively for laparoscopic and open surgery but less experienced surgeons had differing recurrence rates of 12·3% and 2·5%. Indeed, the poor results for laparoscopic surgery are entirely derived from less experienced surgeons. In their discussion they comment ‘These results should be interpreted cautiously.’ I fail to see any good reason why! The data is very clear. Put into context, a recent report of TAPP surgery⁶ in over 3,000 UK patients has reported a recurrence rate of 0·16%, 50 times better than the Utah study. Our own experience in Edinburgh has also confirmed that results from laparoscopic surgery in the learning phase are poorer whereas, the open mesh repair has good results even in the hands of early stage trainees. TEP surgery is demanding. The anatomy is not well understood by most surgeons and the operating space is much smaller than the peritoneal cavity in which most laparoscopic surgery is done. This requires a higher degree of hand-eye coordination. A small quantity of blood can dramatically reduce vision and accidental puncture of the peritoneum, easily performed, reduces vision further. Many authors have emphasised the technical demands of TEP surgery and the long learning curve.

Are keyhole operations worse for hernia? Yes, if your surgeon is inadequately trained; but, No, if well trained and experienced. Most general surgeons in the UK and abroad are not trained in this particular technique but almost all do hernia surgery. There is little doubt that specialist surgical centres gain the best results but the NHS has not been known for developing such centres except in highly specialised fields like transplant surgery. If inguinal hernia surgery was to be removed from general surgery and become a specialist operation, such a move would not be warmly received by many for a variety of reasons, not least the potential loss of income that would follow. Nonetheless, this would be the quick fix solution. An alternative approach would be an aggressive training program targeting existing consultants, possibly supported, indeed led by the Royal Colleges. If we are to derive the undoubted benefits of laparoscopic hernia surgery without reliving the disaster years of the early 1990s then training is the key to successful keyhole surgery. Surgeons need to learn how to learn.⁷

References

1. Hair A, Duffy K, McLean J et al. Groin hernia repair in Scotland. Br J Surg 2000; 87(12):1722–6.
2. The MRC Laparoscopic Groin Hernia Trial Group. Laparoscopic versus open repair of groin hernia: a randomised comparison. Lancet 1999; 354(9174):185–90.
3. Annadale T. Case in which a reducible oblique and direct inguinal and femoral hernia existed on the same side and were successfully treated by operation. Edinburgh Medical Journal 1876; 21:1087.
4. National Institute for Clinical Excellence. Guidance on the use of Laparoscopic surgery for inguinal hernia. Technological Appraisal Guidance No. 18. London: NICE; 2001.
5. Neumayer L, Giobbie-Hurder A, Jonasson O et al. Open Mesh versus Laparoscopic Mesh Repair of Inguinal Hernia. N Engl J Med 2004; 350(18):1819–27.
6. Kapiris SA, Brough WA, Royston CM et al. Laparoscopic transabdominal preperitoneal (TAPP) hernia repair. A 7-year two-center experience in 3017 patients. Surg Endosc 2001; 15(9):972–5.
7. Wojtyczka N, Wente MN, Wenning M et al. Surgeons learn how to learn. Study of 76,499 herniorrhaphies performed between 1993 and 1997 registered by the chamber of physicians in Westfalia-Lippe. Chirurg 2003; 74(4):353–9; discussion 359–60.