Compulsive lying on the back is a position in which the patient lies on his back with his legs flexed to relieve tension on the abdominal muscles in order to relieve the pain of the disease. It is commonly seen in acute peritonitis. Secondary peritonitis Acute perforation and rupture of intra-abdominal organs: the most common cause of acute secondary peritonitis. Perforation of cavernous organs often occurs suddenly due to progression of ulcerative or gangrenous lesions, e.g., acute appendicitis, peptic ulcer, acute cholecystitis, typhoid ulcer, gastric or colon cancer, ulcerative colitis, ulcerative intestinal tuberculosis, amebic bowel with diverticulitis. Forced supine examination is mainly laparotomy: laparotomy is a simple, easy and economical examination method. If intra-abdominal fluid can be obtained, the naked eye alone can usually determine whether there is peritonitis and what type of peritonitis, together with microscopic examination, bacterial smear and necessary biochemical tests (such as amylase determination), the diagnostic value is higher. Tuberculous peritonitis is grass green transparent ascites; acute perforation of the gastroduodenum is yellow, turbid, containing bile, no odor; perforation after a full meal may contain food residue; acute severe pancreatitis is bloody, pancreatic amylase content is high; acute appendicitis perforation is dilute pus slightly smelly; narrower intestinal obstruction is bloody, heavy odor; if the abdominal perforation is complete fresh non-coagulable blood is If the laparotomy is complete with fresh non-clotting blood, then it is considered to be a substantial intra-abdominal organ injury, and it should be excluded whether the organ or blood vessel is pierced. For secondary peritonitis, the site of the primary lesion should be determined to consider further treatment. However, this is sometimes not easy when signs of peritonitis are evident. Generally, an X-ray showing free gas under the diaphragm is suggestive of gastrointestinal perforation. If the symptoms do not improve after gastrointestinal decompression and initial treatment, the possibility of gallbladder perforation should be considered. Female patients should consider tubal and ovarian inflammation, and elderly patients should consider the possibility of colon cancer or diverticulum perforation. Pleurisy and pneumonia can cause fever, epigastric pain, and acute myocardial infarction can have severe epigastric pain. Acute pancreatitis, perinephric abscess, and even herpes zoster can also cause fever and abdominal pain. However, it is not difficult to differentiate them according to medical history, physical signs and corresponding examination.