External Hernia

　　The occurrence of external hernia is related to two major factors: weakened abdominal wall strength at the site and increased intra-abdominal pressure.

　　1, Weakened abdominal wall strength:It belongs to the anatomical structure reason, which is the basis of hernia occurrence, and there are two types: congenital and acquired. Congenital conditions include incomplete closure of the peritoneal processus, high inferior margin of the internal oblique muscle, wide inguinal triangle, incomplete closure of the umbilical ring, and defects in the linea alba. Some normal anatomical phenomena, such as the spermatic cord passing through the inguinal canal and the femoral arteries and veins passing through the femoral canal area, can also cause weakened abdominal wall strength at this location. Acquired causes include poor healing of surgical incisions and drainage sites, trauma, inflammation, infection, surgical cutting of abdominal wall nerves, excessive fat infiltration in obese individuals, muscle atrophy and degeneration in the elderly, and abnormal collagen metabolism, causing the firm fascial tissue to be replaced by a loose and microporous connective tissue layer or fat.

　　2, Increased intra-abdominal pressure:It is a predisposing factor with many causes, such as chronic cough (such as smokers and elderly bronchitis), chronic constipation, late pregnancy, ascites, difficulty in urination (prostatic hypertrophy, phimosis), frequent crying of infants, lifting heavy objects, frequent vomiting, and abdominal tumors, etc.

　　Common complications of external hernia include intestinal strangulation and intestinal perforation.

　　Patients with intestinal strangulation often have fever, persistent abdominal pain, and a mass in the abdomen after gastrointestinal decompression. Laboratory examination shows significant leukocytosis, metabolic acidosis, elevated lactate dehydrogenase and amylase. X-ray examination is not sensitive, but it will show signs such as coffee bean sign (a single gas-filled cavity separated by a wide and dense band of edematous intestines), pseudotumor sign (intestine filled with fluid, completely closed), or a single mass fixed in three different planes.

　　Perforation of the intestine refers to the process in which the intestinal lesions penetrate the intestinal wall, causing the intestinal contents to overflow into the peritoneal cavity. It is one of the serious complications of many intestinal diseases, causing severe diffuse peritonitis, mainly manifested as severe abdominal pain, abdominal distension, and symptoms of peritonitis. In severe cases, it can lead to shock and death.

　　According to the pathological changes of the contents of an external hernia, it is divided into the following types, and each type has its corresponding clinical manifestations.

　　1. Reducible hernia

　　The sac neck of this hernia is relatively wide and large, and the hernia contents are easily reducible into the abdominal cavity. When standing, walking, coughing, or straining to defecate or urinate, the intra-abdominal pressure increases, and the hernia contents protrude. They can be reduced by lying down and resting or gently pressing. When the hernia contents protrude, there is a feeling of descent, and generally no other discomfort.

　　2. Irreducible hernia

　　If the course of the disease is long or a hernia belt has been used, the sac neck may be rubbed thickened and less extensible, and the hernia contents may also become adherent to the sac neck, making it difficult or only partially reducible. Other clinical manifestations are the same as those of reducible hernia. If the hernia contents are peritoneal interposed organs, such as the cecum or bladder and their serosa, they also become part of the hernia sac, and are also known as sliding hernia. The contents are generally not completely reducible.

　　3. Incarcerated hernia

　　If the intra-abdominal pressure suddenly increases, the hernia contents are forcibly herniated and trapped in a narrow and rigid hernial ring, and cannot be reduced. There is no blood circulation obstruction in the hernia contents. The clinical manifestations include the enlargement of the hernia mass, severe pain, and inability to reduce. If the hernia contents are the intestinal tract, symptoms of acute intestinal obstruction may occur. If only a part of the intestinal wall is incarcerated, and the intestinal cavity is not completely blocked, the clinical manifestations of intestinal obstruction may be not obvious. This type of intestinal wall hernia is also known as Richter hernia. If the Meckel diverticulum is incarcerated, it is called Littre hernia. If two segments of the intestinal tract are incarcerated, it forms a reverse incarcerated hernia in the shape of the letter 'W', also known as Maydl hernia. The seriousness of this hernia lies in the fact that both the hernia sac and the abdominal cavity have incarcerated intestinal tract. There is a possibility of missing the incarcerated intestinal tract in the abdominal cavity during surgery.

　　4. Strangulated hernia

　　If the hernia contents become incarcerated and blood circulation is obstructed, it will transform into a strangulated hernia. The pathological process is that venous blood circulation is blocked first, resulting in congestion and edema of the tissues, and eventually leading to venous blood circulation obstruction and tissue ischemic necrosis. Infectious exudate in the hernia sac can also flow into the abdominal cavity, causing peritonitis. The clinical manifestations are much more severe than those of incarcerated hernia. The hernia mass increases, the pain intensifies, and may be accompanied by symptoms of intestinal obstruction and sepsis. After the intestinal tract is necrotic, local redness, heat, and tenderness, as well as acute inflammatory manifestations, may occur. In severe cases, infectious shock may occur, which may be life-threatening.

　　The prevention of external hernia mainly involves paying attention to one's own body. First, it is necessary to change bad habits, keep the bowels regular, as constipation is easy to cause an external hernia; therefore, when constipation occurs, measures for defecation should be taken, and it is not advisable to force defecation. It is necessary to participate in physical exercise regularly to enhance physical fitness and prevent the occurrence of diseases. When doing heavy physical work, attention should be paid to self-protection to prevent a sudden increase in abdominal pressure, which may lead to the formation of an external hernia.

　　For an external hernia, a chest X-ray should be performed first to understand whether there is any lung disease. If there is a suspicion of diaphragmatic hernia, a frontal and lateral chest X-ray should be taken, and barium meal and barium enema examinations should be performed to confirm the diagnosis.

　　1. Inquire about the onset time of the illness, and whether there is a history of chronic cough, frequent vomiting, constipation, rectal prolapse, urethral stricture, phimosis, bladder calculi, difficult urination, abdominal surgery, trauma, and other medical history. Is there a history of hernia incarceration in the past?

　　3. Auxiliary examination chest X-ray to understand whether there is lung disease. Those suspected of having diaphragmatic hernia should take anteroposterior and lateral chest films, and perform barium meal and barium enema examinations to confirm the diagnosis.

　　2. Physical examination should pay attention to whether there is any abnormal bulging or indentation in the abdomen, ascites, enlargement of the liver and spleen, or a mass protruding when standing. The elderly should be examined for benign prostatic hyperplasia. Whether there is limited respiratory movement on one side of the chest, weakened respiratory sounds, fullness between the ribs, and whether bowel sounds or fluid sounds can be heard in the chest, etc., are signs of diaphragmatic hernia. For inguinal hernias, attention should be paid to the shape and size of the hernia ring, whether the contents fall into the scrotum when standing or coughing, and whether it can be reduced. It is necessary to understand whether there is strangulation or incarceration, and to determine the type of hernia. It should be distinguished from other diseases in the scrotum. For those suspected of having fluid in the scrotum, a light transmission test should be performed.

　　Patients with external abdominal hernia must quit smoking and drinking, try not to drink strong tea, and eat warm, soft food, taking small and frequent meals. Regularly, you can eat some foods with the effect of invigorating the Qi, such as beans, yam, chicken, eggs, fish, and meat.

　　The treatment principle of external abdominal hernia is to find and treat the etiological factors of the disease.

　　1. Non-surgical treatment: For inguinal hernias in children under 1 year of age, surgery can be postponed temporarily. A cotton string tie can be used to compress the inguinal ring to prevent the hernia mass from protruding. Some can be cured spontaneously as the abdominal muscles gradually become strong during growth and development. For umbilical hernias in children, a adhesive plaster method can be used, which involves pushing the umbilical hernia back, placing a small piece of soft plush under the umbilicus, and using a 5 cm adhesive plaster from one side of the midaxillary line to tightly adhere to the umbilicus. Change once every 1-2 weeks, and it can be cured within half a year. However, due to the possibility of allergic reactions to adhesive plasters, a 5 fen-sized metal plate can also be used, pierced with a string, wrapped in soft plush, and pressed on the umbilicus, with the string wrapped around the waist and tied. For the elderly and weak who are not suitable for surgery, a hernia belt can be used to compress the inguinal ring, tied during the day, and untied during rest.

　　For early incarcerated hernias,手法复位 should be tried in the hospital. After successful reduction, observe for 24 hours and pay attention to whether the abdominal disease has improved.

　　2. Surgical treatment: In principle, surgical treatment should be performed for all types of external abdominal hernias. There are many treatment methods, but the general principle is to perform high ligation of the sac neck, hernia repair, and herniorrhaphy.