Anastomotic fistula is one of the common complications after gastric cancer surgery, and its incidence has been reported to be about 2.2% in China. Anastomotic fistula is a risk factor for patient safety after gastric cancer surgery and can even lead to death.
What might cause an anastomotic fistula?
It is not clear what causes an anastomotic fistula, and it may be the result of a combination of factors. The following factors may affect anastomotic healing in patients with gastric cancer.
- General nutritional status By the time gastric cancer is detected most patients already have significant symptoms and their diet is usually compromised, resulting in poor overall nutritional status, plus the fact that patients have to undergo an open surgery, which is very traumatic, and postoperative fasting may affect postoperative recovery, including affecting anastomotic healing and increasing anastomotic risk of fistula.
- Surgical impact The time of surgery is also a factor in anastomotic healing, and the longer the surgery, the greater the chance of an anastomotic fistula, which can significantly affect anastomotic healing. Vascular and tissue damage during surgery can also affect anastomotic healing, especially in patients with severe and advanced disease, in order to achieve the effect of radical gastric cancer, the scope of surgery and surgical trauma are usually larger, the amount of bleeding is also relatively large, and sometimes even joint organ removal is required. This can cause anastomotic fistula.
- The patient’s own condition The patient’s own physical condition and underlying medical conditions can also have an impact on anastomotic healing. Some studies have suggested that diabetes can be an influential factor in postoperative anastomotic fistulae, and that patients with long-term diabetes usually have a poor systemic vascular condition that can affect the peri-anastomotic blood supply, which in turn can affect anastomotic healing and lead to anastomotic fistulae, but there are studies that do not support this view.
- Adjuvant radiotherapy Because gastric cancer is usually found at a late stage, some patients may require preoperative neoadjuvant chemotherapy first to achieve surgical cure. Preoperative chemotherapy drugs may have an inhibitory effect on anastomotic healing, leading to anastomotic edema, poor blood flow, and increased risk of anastomotic fistula. Therefore, physicians generally recommend that patients who receive preoperative chemotherapy undergo surgery after a certain period of time following chemotherapy to reduce unnecessary risks.
- Patients’ postoperative eating arrangements Patients with gastric cancer surgery generally fast for a long time after surgery, and postoperative eating needs to follow a certain pattern, from trial meals to liquid diet, semi-liquid diet, and finally to general diet, in a gradual manner. If the patient does not follow the doctor’s advice to eat large, indigestible food too early, the food will squeeze the anastomosis causing intestinal obstruction and anastomotic fistula.
What manifestations suggest anastomotic fistula?
Patients with gastric cancer should be alert for anastomotic fistula if they have persistent fever with epigastric pain, signs and symptoms such as gastrointestinal fluid draining from the drainage tube (usually cloudy and may be mixed with blood), increased heart rate, and elevated white blood cells on blood tests after surgery.
How to manage an anastomotic fistula after it occurs?
Anastomotic fistulas usually occur 7 to 9 days after surgery, and once they do, they should be promptly communicated to the physician for medical treatment. The doctor will usually ask the patient to fast from water, administer parenteral nutrition (i.e., nutrition through a vein), anti-inflammatory therapy, and give treatment that inhibits gastrointestinal secretion (e.g., growth inhibitors).
If the fistula is small, surgical treatment is usually not required. After the drainage is significantly reduced, the physician will discontinue treatment to suppress gastrointestinal secretion and gradually administer enteral nutrition, while observing changes in drainage, continuing anti-infective treatment, and regularly checking blood tests and other indicators. Finally, the doctor will perform gastrointestinal imaging at his discretion to check whether the anastomosis is healing.
For patients with non-decreasing gastrointestinal fluid drainage, persistent fever, and persistent elevated blood count, if the above treatment is not effective, reoperation may be required to eliminate the fistula. (Coauthored by Han Chao, Department of Gastrointestinal Oncology, The First Hospital of China Medical University)