Moshe Schein
“If there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong.” (Murphy’s Law, Arthur Bloch) Somebody’s leak is a curiosity – one’s own leak is a calamity.
There are two chief clinical patterns of postoperative intestinal leak:
The leak is obvious – you see intestinal contents draining from the operative wound or from the drain site (if a drain was used).
You suspect a leak but do not see one.
Scenario 1: The Obvious Leak
It is postoperative day 6 after a laparotomy for small bowel obstruction (> Chap. 21).
The procedure was uneventful, except for two accidental enterotomies, which were closed with interrupted Vicryl 3-0 in one layer. During morning rounds the patient complains:
“look, doctor, my bed is full of this green stuff ”. You uncover the patient’s abdomen to see bile-stained intestinal juice pouring through the incision! Now you are very upset. True, the patient’s recovery was not smooth; he was running a fever and a high white cell count. And now this terrible disaster! It is a disaster indeed, for even today around one-third of patients with intestinal suture-line breakdown die.
Your first reaction is, “Let’s get him to the operating room immediately and fix this mess”. Is this advisable?
The Controversy
There is little controversy that established postoperative external enteocuta- neous fistulas, which usually result from leaking anastomoses or incidental entero- tomies, should initially be managed conservatively. As noted in previous chapters, there is also little controversy that acute gastrointestinal perforation, be it sponta- neous or traumatic, is an indication for an emergency laparotomy to deal with the source of contamination/infection (> Chap. 12).
So what about the “early postoperative small bowel leakage”? Is it a “simple perforation” requiring an immediate operation, or a “fistula” to be managed con- servatively? We contend that this scenario represents both conditions and should therefore be managed selectively in the individual patient.
The Role of Non-operative Management
With proper supportive management, and in the absence of distal obstruction or loss of bowel continuity, more than half of postoperative small bowel fistulas will close spontaneously within 6 weeks. Those which fail to close by this time will require elective re-operation. When performed on an anabolic, non-SIRS patient, in a less hostile peritoneal environment, a procedure will restore the integrity of the gastrointestinal tract with an acceptable risk of complications.
A crucial issue when deciding on a trial of conservative management is the presence or absence of peritonitis or sepsis; clinical peritonitis is an indication for an immediate operation. Even when clinical peritonitis is not present, any evidence of SIRS or sepsis should promote an aggressive search for drainable intra-abdomi- nal pus. This is best done with a CT scan; associated abscesses should be drained, percutaneously (PC) or at laparotomy (> Chap. 44).
Remember: in unselected series of postoperative enteocutaneous fistulas a third of patients die – the vast majority from neglected intra-abdominal in- fection.
The Role of Operative Management
As stated above, peritonitis or a complex intra-abdominal abscess not suitable for, or responding to, PC drainage, are an indications for laparotomy. But why not operate on all such patients? Why not just surrender to the temptation buzzing in your brain: “I know where this leak is coming from; let me just return to that abdomen and fix the small problem with a few more sutures”? Why won’t resutur- ing the leak solve the problem?
Primary Closure of a Disrupted Intestinal Suture Line is Doomed to Fail
We can all remember an isolated success in closing an intestinal leak, but the collective experience points to an overwhelmingly high rate of failure. Attempts to close an intestinal leak, after a few days, in an infected peritoneal cavity are doomed to fail. Re-doing an intestinal anastomosis in the presence of postoperative perito- nitis is an exercise in futility. Obviously, if successful the surgeon is a hero who saves his patient a prolonged hospitalization and morbidity. If, however, a leak re-develops, as it usually does, it produces a tremendous “second hit”, which strikes an already primed,susceptible and compromised host (> Chap.48).Sepsis and death are then almost inevitable.
Suggested Approach to Early Postoperative Intestinal Fistula
Trial of conservative management is warranted when:
There is no clinical peritonitis.
There are no associated abscesses on CT and you know the leak is “controlled”.
You know, or can accurately guess at, the underlying cause of the leak – you were the one to perform the first operation and know with reasonable cer- tainty what the source of the leak is (an anastomosis or an enterotomy).
An immediate re-laparotomy is warranted when:
There is evidence of clinical peritonitis.
There is “ SIRS/sepsis” with proven or suspected intraperitoneal abscesses (an attempt at PC drainage may be in order, however).
Abdominal compartment syndrome exists.
Somebody you do not trust performed the primary,“index”, operation. Bitter experience has taught us that in such cases “anything is possible” and it is better to re-operate – you never know what the findings will be.
What to Do During an Emergency Re-laparotomy?
There are three things to consider: (1) the condition of the bowel, (2) the condition of the peritoneal cavity, and (3) the condition of the patient.
Very rarelyin a stable, minimally compromised patient, when peritonitis is macroscopically minimal, when the bowel appears of “good quality”, when the patient’s serum albumin levels are reasonable,we would resect the involved segment and re-anastomose. Such a sequence of events is possible only when the leak pre- sents within a day or two after the operation (usually caused by a technical mishap).
An immediate re-operation before local and systemic adverse repercussions develop may thus provide definitive cure. If conditions are not so propitious though, the less heroic but logical and life saving option of exteriorization of the leaking point as an enterostomy should be carried out, and at any level.
Conservative Management
The principles of management are few and simple.
Restore fluid and electrolyte balance. All the fistula’s losses should be measured and replaced.
Protect the skinaround the fistula from the corrosive intestinal juice. A well- fitting colostomy bag around the fistula often does the trick. Otherwise place a tube
connected to a continuous suction source adjacent to the fistula, place stomadhe- sive sheaths around the defect, and cover the entire field with an adhesive transpar- ent dressing (similar to the “sandwich” described in > Chap. 46 but without the mesh). Make generous use of Karaya and/or zinc paste to protect the skin around difficult-to-manage, complex fistulas. Although such wounds require lots of effort and dedication they are almost always manageable – but only if you care.The way the abdominal wall of your fistula patient looks is how you look!
Provide nutrition.Proximal gastrointestinal fistulas require TPN initially until a nasal feeding tube is inserted beyond the leak level. Distal small bowel and colonic fistulas will close spontaneously whether the patient is fed orally or not.As emphas- ized in > Chap. 41, using the intestine for feeding – if possible – is better. In high fistulas it is often possible,and beneficial,to collect the fistula’s output and re-infuse it, together with the enteral diet, into the bowel below the fistula.
Delineate anatomy.This is best done with a sinogram – injecting water-soluble contrast into the fistula tract. This will document the level of the bowel defect and the absence of distal obstruction and loss of continuity – prerequisites for success- ful conservative management.
Exclude and treat infection. This has been mentioned above and is repeated here only to emphasize that when your fistula patient dies it is usually because you were not aggressive enough in pursuing our advice.
Gimmicks
The initial output of a fistula has few prognostic implications. A fistula which drains 1000 ml/day during the first week has the same chance of spontaneously sealing as one with an output of 500 ml/day.Artificially decreasing a fistula’s output with total starvation and administration of a somatostatin analogue is cosmetically appealing but not proven to be beneficial.
In patients with a well-established (and long) fistula tract (which takes a few weeks to develop) it is possible to hasten the resolution of the fistula by blocking the tract.Many “innovative”methods have been reported as successful (usually in small series of patients), ranging from the injection of fibrin glue (through a fiberscope) deep into the tract, to plugging the tract’s orifice with chewing gum (chewed by the patient not by you…).
Fistula Associated with a Large Abdominal Wall Defect
Not uncommonly the end result of intestinal leaks and re-operative surgery is an abdominal wall defect with multiple intestinal fistulas in its base. This so-called complex or type IV fistula represents a catastrophe, which carries a very high
mortality rate. (According to our classification (Schein M, Decker GAG. Postopera- tive external alimentary tract fistulas.Am J Surg.1991; 161: 435–8) type A are foregut fistulas,type B,small bowel,and type C,colonic).The distance of the fistulous open- ing in the intestine from the surface of the defect and the condition of the peritoneal cavity have bearing on the treatment of this condition. It is practical to distinguish between two situations (> Fig. 45.1):
Type IV-A fistulas. When the fistula is located in the depths of the infected abdominal defect, the prolonged contact of large peritoneal surfaces with gastro- intestinal contents allows increased absorption of toxic products, perpetuating local and systemic inflammatory responses and organ dysfunction. In such instan- ces re-operation is necessary to exteriorize or divert the intestinal leak away from the defect. Otherwise, the patient is doomed, as more than half of the patients with this type of postoperative fistula die!
Type IV-B fistulas. Those are “exposed” fistulas near the surface of the defect.
Also called “bud” fistulas they result from damage to intestine exposed at the base of the defect. Because the peritoneal cavity is usually clean and sealed away from intestinal contents,an expectant approach is indicated as early attempts at intestinal reconstruction are hazardous during the resolution of severe peritoneal inflam- mation.A simple rule of thumb is that the condition of the abdominal wall defect reflects the condition of the peritoneal cavity.A well-contracted abdominal wall defect, and fistulas that look like surgical stomas are indicators that an elective intervention is possible and safe (> Chap. 46).
Fig. 45.1. Type IV-A fistulas vs. Type IV-B fistulas
Note: an “exposed-bud” fistula may be dealt with temporarily (until definitive reconstruction) using the following technique: define the mucosal and submucosal layer of the pouting intestinal hole, close it with a fine monofilament suture. Im- mediately cover the repaired bowel and the surrounding abdominal wall defect with a split-thickness skin graft. This should be successful in half of your attempts.
Scenario 2: You Suspect a Leak but Do Not See One
Your patient is now a week after an uneventful right hemicolectomy for a carcinoma of the cecum. She is already at home, and eating, when a new pain develops on the right side of her abdomen, accompanied by vomiting. The patient returns to the emergency room.
She is febrile, her right abdomen is tender with a questionable mass, the abdominal X-ray suggests an ileus or partial small bowel obstruction (> Chap. 43), the white cell count is elevated. You suspect an anastomotic leak.
From a clinical standpoint there are three types of intestinal leaks that
“you cannot see”:
Free leak. The anastomosis is disrupted and the leak is not contained by adjacent structures. The patients usually appear “sick”, exhibiting signs of dif- fuse peritonitis. An immediate laparotomy is indicated as outlined above.
Contained leak.The leak is partially contained by peri-anastomotic adhesions to the omentum and adjacent viscera. The clinical abdominal manifestations are localized. A peri-anastomotic abscess is a natural sequela.
A mini-leak. This is a “minute” anastomotic leak – usually occurring late after the operation when the anastomosis is well sealed off. Abdominal manifesta- tions are localized and the patient is not “toxic”.A mini-leak is actually a “peri- anastomositis”– an inflammatory phlegmon around the anastomosis.Usually it is not associated with a drainable pus-containing abscess.
In the absence of diffuse peritonitis you should document the leak and grade it. Colonic anastomoses are best visualized with a Gastrografin enema. For upper gastrointestinal and small bowel anastomoses give Gastrografin from above. We usually combine the contrast study with a CT – searching for free intraperitoneal contrast or abscesses. There are a few possibilities:
Free leak of contrast into the peritoneal cavity (a lot of free contrast and fluid on CT).You have to re-operate. We previously discussed what to do: it’s best to take down the anastomosis.
Contained localized leak (a local collection or abscess on CT). The rest of the peritoneal cavity is “dry”. This is initially treated with antibiotics and PC drainage
(> Chap. 44).
No leak on contrast study (a peri-anastomotic phlegmon on CT). This re- presents mini-leak or “peri-anastomositis” and usually resolves after a few days of antibiotic therapy.
Note that a contained leak or a mini-leak may be associated with an obstruc- tion at the anastomosis – a result of the local inflammation.Such obstruction usually resolves spontaneously (within a week or so) after the pus has been drained and the inflammation has subsided (> Chap. 43).
Conclusion
We have tried to persuade you that an anastomotic leak is not one disease but a variety of conditions requiring customized approaches. To keep morbidity at bay, tailor your treatment to the specific leak,its severity and the condition of the affected patient.Above all – remember that non-drained intra-peritoneal bowel contents and pus are killers – often silent ones.
We tend to remember best those patients we almost killed; we never forget those we actually managed to kill.
Good surgeons operate well; great surgeons know how to manage their own complications.
