Parastomal hernia

　　1. Etiology

　　The occurrence of parastomal hernia is closely related to the patient's overall and local conditions. Abdominal wall weakness, increased postoperative abdominal pressure, malnutrition, obesity, and local infection are all the bases for the occurrence of parastomal hernia. At the same time, the selection of stoma site, stoma technique, and the occurrence of parastomal hernia are also obviously related.

　　1. Malnutrition:Malignant tumors, anemia, hypoproteinemia, excessive obesity, diabetes, incomplete liver and kidney function, and vitamin deficiency, all can affect postoperative tissue repair. If the intestinal tract (or ureter) and artificial channel are not completely healed, it increases the chance of parastomal hernia.

　　2. Tissue defect in the stoma area:If there is tissue defect in the stoma area, the contraction of transverse muscles, etc., causes the surrounding tissue of the stoma to contract towards all directions, resulting in the expansion of the stoma diameter.

　　3. Degenerative changes in abdominal wall muscles:In elderly patients, the abdominal wall muscles show degenerative changes, reducing their repair capacity and strength.

　　4. Radiotherapy and chemotherapy:The majority of stoma (opening) patients are those with colorectal tumors, bladder tumors, intestinal obstruction, Crohn's disease, etc., who often require radiotherapy and chemotherapy after surgery, affecting the metabolism of normal tissues and wound repair.

　　5. Improper surgical operation:Common situations include: ①Rough surgical manipulation, excessive damage to blood vessels or nerves leading to muscle atrophy and reduced abdominal wall strength. ②Inadequate aseptic operation, incomplete hemostasis, and incision infection after surgery. ③Unsatisfactory anesthesia, forced traction and suture, excessive local tension, and poor alignment of tissues in different layers.

　　6. Inappropriate selection of stoma location:It is generally believed that the incidence of stoma parietal hernia is closely related to the selection of stoma location. Studies have shown that the rectus abdominis muscle has a restrictive function, and the incidence of stoma parietal hernia is lower for those with transrectus abdominis stomas. Those with stoma parietal hernia through the lateral rectus abdominis muscle or incision have a relatively higher incidence. Stomal extraperitoneal stoma can further reduce the incidence of stoma parietal hernia and early postoperative internal hernia.

　　7. Increased intraperitoneal pressure:After surgery, patients may experience severe coughing, severe abdominal distension, difficulty in urination, ascites, or the presence of a large abdominal tumor, as well as crying in infants and young children, which can lead to increased intraperitoneal pressure, thereby triggering the occurrence of stoma parietal hernia.

　　Second, pathogenesis

　　There are two methods of classification for stoma parietal hernia.

　　1. Classification according to the position of the hernial content:There are four types: ① True stoma parietal hernia: a peritoneal sac protruding from an enlarged fascial defect. The most common clinical type, accounting for about 90% of stoma parietal hernias; ② Intermuscular hernia: fascial defects enlarge, abdominal intestinal loops accompany the stoma intestinal loops to protrude subcutaneously, and this type is often associated with prolapse; ③ Subcutaneous prolapse: the fascial ring is intact, the intestinal loops are long and protrude subcutaneously, which is a false hernia; ④ False hernia: due to weak abdominal wall or lateral rectus muscle nerve injury, the stoma intestinal loops prolapse.

　　2. Classification according to the size of the hernia body.

　　1. Chemical dermatitis:Due to the traction of the protruding hernial content on the abdominal wall skin, it has destroyed the sealing of the stoma, leading to leakage of intestinal fluid and other secretions, stimulating the skin to undergo inflammatory changes, and causing redness, swelling, pain, and erosion.

　　2. Incarceration of stoma parietal hernia:Patients may experience severe pain, abdominal distension, nausea and vomiting, cessation of flatus and defecation, and other severe symptoms. The mass cannot be reduced and is accompanied by tenderness. Immediate emergency surgery is required.

　　It is related to the size of the stoma parietal hernia and whether complications occur. In the early stage, there may be no obvious clinical symptoms or only a subcutaneous mass protruding next to the stoma, which appears during long-term standing, walking, coughing, straining for defecation, or urination, and decreases or disappears during rest or lying flat. The mass will gradually increase, as the hernia sac expands and stretches the abdominal wall and stoma, some patients may experience local dull pain,坠胀感, fullness, indigestion, constipation, and other discomforts. Large hernias can affect dressing and daily life.

　　According to the causes of stoma parietal hernia, take different targeted measures:

　　1. Overweight patients should control their weight appropriately and strengthen abdominal muscle exercise.

　　2. The selection of stoma location should be appropriate. Key points: ① The stoma location should be preferably chosen on the lower left abdomen or upper right abdomen; ② The stoma should be made adjacent to the abdominal incision, and it should be avoided to make a stoma through the abdominal incision; ③ It is preferable to choose a transrectus abdominis stoma or an extraperitoneal stoma.

　　3. The size of the stoma should be appropriate, generally with a diameter between 1.5 to 2.0 cm, and the size can be appropriately increased for overweight individuals, with the protruding intestinal tract elevated about 1 cm above the skin.

　　4. Perform strict aseptic operation during surgery, avoid rough handling, stop bleeding thoroughly, prevent incision infection, and appropriately apply antibiotics.

　　5. Select an appropriate anesthesia with satisfactory effects, ensuring that tissue suture is performed under non-tension conditions.

　　6. Strengthen nutritional support treatment after surgery.

　　7. Actively treat diseases that cause increased intra-abdominal pressure.

　　1. First go to general surgery for abdominal examination to determine if there is any suspected hernia. If necessary, perform ultrasound and abdominal flat film examination to clarify.

　　2. For patients with umbilical hernias without complications, the main examination includes physical examination, liver function, renal function, electrolytes, and C-reactive protein tests.

　　3. For patients with other diseases such as lung and abdominal diseases but unclear diagnosis, the examination program can include liver function tests and blood urea nitrogen (BUN), blood creatinine, and ultrasonic examination of gastrointestinal diseases.

　　1. What food is good for incisional hernias:

　　The initial diet should gradually progress from liquid to semi-liquid to regular food. The food should be clean, hygienic, and fresh. Drink plenty of water and eat more fruits and vegetables.

　　2. What food should not be eaten for incisional hernias:

　　Eat less fried and刺激性 food; during the recovery period, food should be eaten in a quantitative manner, chewed slowly, and prevent overeating. Eat less food that is easy to produce gas, such as beans, cabbage, chives, onions, sweet potatoes, carbonated drinks, etc.

　　(The above information is for reference only; for details, please consult a doctor.)

　　Firstly, non-surgical treatment

　　For patients with small hernias and no obvious discomfort, abdominal belts, stoma belts, and pressure bandages can be used for compression bandaging, or circular pressure devices can be used to fix the stoma (orifice) around the surrounding tissue to prevent further herniation of the viscera.

　　Secondly, surgical treatment

　　For patients with incisional hernias who cannot tolerate surgery due to advanced cancer (including palliative surgery and those with abdominal or distant metastasis) and severe internal medical complications, surgical treatment is possible. There are two methods: in-situ hernia repair and stoma shift.

　　1. In-situ Hernia Repair Surgery:For incisional hernias with minor fascial defects adjacent to the stoma, an incision can be made on the lateral side of the stoma, the hernia sac found and excised, the contents of the hernia returned, the stoma repositioned, and the defect sutured in an interrupted manner. For those with large defects and difficulty in direct repair, synthetic materials (prosthetic mesh) can be used for repair, and it is generally advocated to repair from the inside of the abdominal cavity.

　　2. Stoma Shift:For patients who are not satisfied with the original stoma or have recurrence after in-situ repair, the stoma should be shifted. Another median incision is made, and a suitable position is selected for stoma creation through the rectus abdominis muscle. The original stoma is excised and closed.