MEDICAL MATTERS: Doctors in training usually have a fair idea of what they want to specialise in. So when working the obligatory six-month surgical internship, those with no real interest in surgery as a career were usually grateful to share on-call duties with a colleague of a "surgical" persuasion.The reason for this is that such individuals were keen to get "cutting" experience. Dr Muiris Houston reports
By common consensus, performing an acute appendectomy (the removal of a diseased appendix) was where you started. Under the strict supervision of a consultant or senior registrar, the neophyte surgeon was taught how to make a small incision just above the right groin. Having fished out the inflamed organ, he learnt to tie it off with a ligature, remove it and close the incision. A 10-minute procedure in experienced hands, it could stretch to 30 minutes or longer as the young doctor learnt the do's and don'ts of surgical practice.
The vermiform appendix - to give it its full title - is a narrow wormlike protrusion of the gut at a point where the small intestine joins the large bowel. Originally thought to be a vestigial organ with no known function, the appendix is now recognised as being part of the immune system. Though actively participating in the secretion of immunoglobulins, its function is not essential and an appendectomy does not predispose the patient to any increased risk of infection.
A blind pouch, the appendix wins no prizes for good design. At its opening into the gut it is very narrow and is easily blocked. This leads to an initial inflammation of the appendix (appendicitis). Pressure builds up within, bacterial infection sets in, the appendix swells up and it eventually becomes gangrenous as its blood supply is cut off. If left untreated, it then perforates, leading to peritonitis - the spread of pus and infection throughout the abdomen and pelvis.
Although appendicitis remains one of the most common acute surgical diseases, it is on the wane. Between 1975 and 1991, acute appendicitis has declined from 100 cases per 100,000 of the population to 52 cases (per 100,000). This halving of appendicitis cannot be explained by improved diagnosis; the reason for the decline remains elusive.
Apart from affecting the learning opportunities of the surgical tyro, the decline has been mirrored by changes in the approach to managing the condition. Back in 1889, Charles McBurney presented a classic report to the New York surgical society on the importance of early operative intervention for acute appendicitis. He described the point of maximal tenderness in the abdomen which helped to define an accurate diagnosis and five years later, he devised a particular surgical incision which today bears his name.
But one of the problems of intervening too early is the possibility that at operation, a normal, white, un-inflamed appendix is found. While this is usually removed - to save the person a repeat operation in the future - it means that an alternative diagnosis must still be sought.
In fairness to doctors, the diagnosis of acute appendicitis can be very difficult to make - not all show the classic findings of tenderness over the lower right side of the abdomen, accompanied by nausea and vomiting. A test called rebound tenderness - in which the doctor places his hand over the left side of the tummy, presses down and lifts away suddenly with the patient experiencing worse pain "on the rebound" - is helpful. The doctor may also perform a rectal examination, which will reveal tenderness on the right side as his finger presses against the inflamed appendix.
So the surgeons' dilemma has always been between careful re-examination and reappraisal of the patient following admission and making the decision to operate. Intervene too early, and the patient may undergo unnecessary surgery; leave it too late and the appendix may have burst, leading to peritonitis and widespread infection. The death rate from acute appendicitis is less than 0.3 per cent, rising to 1.7 per cent following perforation.
PROBABLY the single greatest advance in surgical practice in the past two decades has been the introduction of the laparoscope. It has significantly changed the management of acute appendicitis. Like a miniature telescope, the laparoscope is inserted through the belly button allowing the surgeon to directly view the appendix. If the appendix is inflamed, it can be removed, using instruments passed through the laparoscope. If it looks normal, unnecessary surgery is avoided and other causes for the symptoms sought.
A systematic review of trials of laparoscopic versus open appendectomy has confirmed the advantage of the minimally invasive option. Laparoscopic appendectomy halved the number of wound infections and reduced postoperative pain, the length of hospital stay and the time taken to return to work. Its principal disadvantage is a threefold increase in the number of postoperative abscesses which occur.
The laparoscopic approach comes into its own when there is a diagnostic dilemma. It is especially useful in young women in whom the difficulty in making an accurate diagnosis is often greatest and has the advantage of being able to detect an ovarian cyst and other gynaecological causes of abdominal pain. Probably the only time to avoid laparoscopy is where there is a strong suspicion that the appendix is perforated. The old-fashioned, full surgical incision is still best for these patients.
As someone who spent two weeks in hospital following a perforated appendix - before the advent of the laparoscope - the advantages of this minimally invasive method of making a diagnosis are obvious. The only challenge that remains is to provide a sufficient number of surgeons skilled in performing laparoscopy on demand - which means the aspiring young surgeon of today, should look for "telescopic training" rather than the "cutting experience" of 20 years ago.