Currently, most of the extra-intestinal fistulas are postoperative complications, and the first operation is already the first operation to perform definitive fistula surgery again, and the number of operations will increase if the definitive operation fails. Therefore, all fistula surgeries are more than two abdominal surgeries. Among our patients with fistulas, there are patients who have undergone more than 12 surgical procedures. When treating these patients, it is clear that surgery for enterocutaneous fistula patients is different from first-time emergency surgery and elective surgery in terms of timing, planning and implementation, and perioperative management, and is highly individual and specific. The experience of multiple surgical treatment of enterocutaneous fistula is presented here.
The timing of reoperation for enterocutaneous fistula patients
The factors that determine the timing of surgery in patients with enterocutaneous fistula include: nutritional status, organ function and the release of abdominal adhesions. According to the current principles of enterocutaneous fistula treatment, it is generally feasible to perform definitive surgery again after the infection is controlled, the nutritional status is improved, and the abdominal adhesions are released about 3 months after the occurrence of an enterocutaneous fistula. Definitive surgery is surgery to eliminate the fistula and restore intestinal patency.
In the case of abdominal adhesions, it generally takes about 3 months between the last surgery for the abdominal adhesions to loosen and facilitate surgical separation. However, time is not a single determinant. The complete release of abdominal adhesions also depends on the extent of the previous surgery, the extent of postoperative bleeding and infection, and drainage. The greater the extent of the extra-intestinal fistula surgery and the more severe the infection, the more the abdominal adhesions will be aggravated, and the abdominal chemotherapy and radiotherapy will further aggravate the abdominal adhesions. Patients with milder infections and less extensive adhesions can also be reoperated about 6 weeks after the occurrence of the fistula. On the contrary, some patients with extensive abdominal infection, poor nutritional status and heavy abdominal adhesions need to wait longer for reoperation, in some cases up to 6 months. In some cases, the waiting time for reoperation has been extended to 10 years due to extra-medical factors. However, most patients can receive reoperation within 6 weeks to 6 months. In any case, the treating surgeon should overcome impatience and must choose carefully the timing of reoperation.
In general, the timing of reoperation for extra-intestinal fistula can be determined from the following aspects: (1) The fistula has no possibility of healing on its own. (2) To understand the extent of surgery or trauma, the presence or absence of extensive peritonitis or abscess formation when the fistula occurred. (3) Periodically examine the abdomen and dynamically observe the presence of inflammatory masses, the degree of abdominal wall tenderness, and the number and tone of intestinal peristalsis. (4) Whether the patient’s nutrition and general condition improve significantly and whether the organ function can tolerate major surgical stress. (5) Abdominal CT examination should also be performed before reoperation to observe the distribution and extent of intra-abdominal adhesions. (6) When possible, the timing of surgery should be advanced to reduce the occurrence of various complications and shorten the treatment time.
If the patient is young, has good organ function, good nutritional status, and is eligible for reoperation, surgery can also be performed within 14 days of the occurrence of extra-intestinal fistula, i.e., early definitive surgery [1].
2. Design and implementation of reoperation protocols for patients with enterocutaneous fistulae
The most profound experience of the authors over the years is that it is important to analyze the causes of the fistula repeatedly before surgery and to design a variety of surgical plans, taking into account all possible intraoperative situations. It is important not to take any chances and wait until the surgery. This kind of thinking often leads to intraoperative unpreparedness for unexpected situations and confusion, which ultimately violates treatment principles.
The function of the heart and lungs and other important organs, especially the condition of the gastrointestinal tract, must be very clear. Specifically, the preoperative routine and special examinations should be improved. Barium meal of the whole gastrointestinal tract (60% pantopamine in case of partial obstruction) and fistulography are used to understand the fistula course and the whole gastrointestinal tract course, and CT of the whole abdomen is used to understand the potential infection and abdominal adhesions [2]. Various routine examinations were then performed to investigate any contraindications to surgery.
It is important to be very clear about what is to be achieved by reoperation and generally there should be three types of prognosis: upper, middle and lower. It is how the best option is designed; what is the second best option; what is the retreat when conditions are the worst, i.e., what is the option to achieve the minimum requirements without increasing the complexity of the disease.
The correct surgical approach is the key to the success of the procedure. Sometimes, the intestinal canal is damaged as soon as the incision is opened. At this point, not only is the mind of the surgeon damaged, but the difficulty of further surgery is significantly increased. It is important to ensure that the reoperative access should be at the site with the least amount of abdominal adhesions and at the same time fully expose the surgical field. This is determined by studying the abdominal imaging findings and repeated palpation of the abdomen to compare the tenderness of the various sites, without adhering to a conventional incision. The incision from the previous surgery should generally be avoided because under this incision is often also where the adhesions are heaviest. If the original incision is still needed, the abdomen should be entered as close as possible to the upper and lower part of this incision without scarring. For those who have multiple vertical incision scars and it is inconvenient to use a vertical incision, transverse epigastric incisions and curved lower abdominal incisions, or even shaped incisions, can be used to enter the abdomen successfully, but the blood flow to the abdominal wall at the incision must be considered.
Successful visualization of the surgical field is also one of the key factors for the successful performance of the procedure. A tip for traction is presented here. Since most abdominal adhesions in patients with intestinal fistula are diffuse, even with successful access, there are still extensive adhesions in the abdominal cavity. It is still difficult to expose the surgical field using a normal retractor (pulling hook). The solution is to use a #7 silk suture to make a suture at an interval of about 5 cm on both sides of the incision in the subcutaneous whole layer, and to use a straight vascular clamp to tighten the suture traction and lift the incision abdominal wall, which will expose the surgical field well. We refer to this method as incisional sling traction.
It is important to separate the adhesions between the intestines with patience and care. Abdominal adhesions are generally classified as membranous adhesions, dense adhesions (scarred adhesions) and inflammatory adhesions. There are two main methods of separating adhesions, namely sharp separation and blunt separation. Sharp separation should be used as much as possible to separate adhesions, but very mature and loose membranous adhesions can also be supplemented by blunt separation. Sharp separation is mainly based on scissors, and the scissors used should be curved blunt-tipped scissors. For dense adhesions, a scalpel can be used for sharp separation, but this requires a good grasp of the softness and anatomy of the adhesions to be separated, as well as a specific feel for the scalpel.
Extra-intestinal fistulas can arise after surgery in various parts of the abdomen, and skill is one aspect when performing extensive adhesion dissection. It is more important to be familiar with the anatomy of the surgical field to prevent damage to tissues and organs other than the intestinal canal, which can increase the complexity and risk of surgery. For specific diseases such as fistulas caused by radiation intestinal injury and tumors, it is not advisable to forcibly dissect the intestinal fistula in order to remove it, but rather to use an open method to restore the patency of the gastrointestinal tract and restore intestinal nutrition. In this way, although a mucus fistula remains, it reduces the patient’s pain and improves the quality of life, which is preferable to the recurrence of fistula and non-healing incision.
It is necessary to emphasize here the method of repairing extraintestinal fistulas and intraoperative intestinal injuries. The surgeon should not be alarmed by the intraoperative rupture of the intestinal canal due to separation. The intestinal canal at the injury can be trimmed first, and then interrupted with fine silk sutures, supplemented by interrupted pulpy sutures to reinforce the repair port. If longitudinal sutures along the intestinal canal are likely to be narrowed, transverse sutures can be used instead. For small fistulae that can be repaired, a similar approach should be taken. If the inflammatory scar and damaged tissue are not removed and the repair is done directly on top of it, the damaged intestine will not heal well.
The causes of extraintestinal fistulas are poor healing of the local anastomosis and repair; and obstruction at the distal end of the anastomosis. Therefore, after dealing with the fistula, the distal intestinal canal should also be fully explored to exclude distal obstruction. For example, if a duodenal stump fistula is complicated by gastrojejunostomy after major gastrectomy, after repairing and removing the duodenal stump, it is important to understand whether there is obstruction of the input collaterals. If necessary, the gastrojejunostomy can be replaced by a jejunal Roux-en-Y anastomosis.
To ensure successful surgery and shorten the operative time, semi-automatic surgical instruments such as purse-string suture forceps, disposable anastomoses and sutures can be used as much as possible.
After completion of the procedure, extensive abdominal irrigation with saline should also be performed. The amount of saline flushing is determined by the degree of abdominal contamination. It is usually above 100 mL/ kg body weight and up to 300 mL/kg body weight. The greatest benefit of abdominal flushing is to reduce abdominal contamination to prevent secondary abdominal infection and to reduce postoperative intestinal adhesions.
The jejunostomy plays both a decompressive and nutritional role in extraintestinal fistula surgery [3]. A jejunostomy tube placed in and near the proximal end of the repair and anastomosis is designed to drain intestinal fluid, reduce pressure on the anastomosis, and ensure healing of the anastomosis. This method is also known as internal drainage. The jejunostomy tube placed distal to the anastomosis is to facilitate early postoperative initiation of enteral nutrition, and also to reduce the cost of treatment for the next surgery and reduce complications such as infection and biliousness associated with long-term parenteral nutrition in the event of recurrent postoperative enterocutaneous fistulae. The long duration of parenteral fistula surgery should not be used as a reason to forego this important insurance measure. Regardless of the purpose of the jejunostomy, the three elements of the Witzel jejunostomy method should be followed, i.e., purse-string fixation, tunnel embedding, and abdominal wall draping to prevent the occurrence of an artificial jejunostomy resulting in an extra-jejunostomy. Avoid choosing latex and silicone tubing for the stoma tube, as these two types of tubes are mostly thicker on the market and have less ability to form sinus tracts themselves. We have experienced that the choice of red rubber catheter for jejunostomy has fewer complications and is less expensive.
Finally, attention should also be paid to postoperative external drainage, which is to place a drip double-lumen negative pressure suction tube (double cannula) in the area where the fistula may occur again, such as the vicinity of the intestinal anastomosis and the repair port and each potential gap. This drainage method, which we have described in detail, has also been a proven method for the treatment of extraintestinal fistulas with abdominal infections for 30 years [4]. The basic principle of this drainage tube is to change passive drainage to active drainage; to change simple drainage to drip-flush drainage, which is also known as a drip double-lumen negative pressure suction tube. Because the so-called double cannula on the market is varied, whether the production materials, or the use of methods and effects are significantly different from the double cannula we currently use. Some of them are active negative pressure drainage, but it is very easy to form a local vacuum and block the catheter, so it is also difficult to achieve the effect of drainage. To differentiate, the double cannula we used recently will be referred to as the Lai double cannula.
3. Key points in the perioperative management of reoperation
In order to maximize the success rate of reoperation in patients with enterocutaneous fistula, it is also necessary to work on the perioperative period of enterocutaneous fistula. Simply put, there are five hurdles to overcome, namely endostasis imbalance, bleeding, infection, organ dysfunction and malnutrition, in order to ensure the success of reoperation in patients with parenteral fistula.
The issues of perioperative nutritional support and infection in patients with parenteral fistulas have been emphasized several times in other articles [4.5] and will not be repeated. It is worth mentioning that because the intestinal function of patients with extra-intestinal fistula is incomplete, artificial nutrition is not yet perfected and vitamin K deficiency is likely to occur, which affects the patient’s coagulation function and should be supplemented in time before surgery. As the patient with an extra-intestinal fistula is re-operated due to separation of adhesions, the stripping surface is mostly large. It is important to stop bleeding properly during surgery. In case of bleeding tendency after surgery, various hemostatic drugs should be used promptly. Sometimes, postoperative massive abdominal bleeding, especially late bleeding with gastrointestinal bleeding is often an early manifestation of extraintestinal fistula, which should be observed and interventions should be taken at the right time.
The oxygen supply should be improved by various methods such as nasal catheter oxygen administration and mask oxygen administration for patients after reoperation for extraintestinal fistula. Patients with pulmonary ventilation and air exchange disorders resulting in pulmonary dysfunction should be ventilated without hesitation by tracheotomy.
Efforts should also be made to use enteral nutritional support for a period of time before definitive surgery for parenteral fistula. Compared with parenteral nutrition, enteral nutrition has the advantages of lower cost, fewer complications, and safety and effectiveness. We found that patients who were able to use enteral nutrition for a period of time before surgery had significantly less abdominal adhesions than those who had been using parenteral nutrition. This may be related to the ability of enteral nutrition to increase intestinal motility. Enteral nutrition can also normalize the intestinal tissues and facilitate postoperative healing without disuse atrophy.