Acute peritonitis

　　The most common bacteria in peritoneal infection are Escherichia coli, Enterococcus, Pseudomonas aeruginosa, Proteus, gas-forming clostridium, and other anaerobic bacteria. In most cases, it presents as a mixed infection. There are many causes of acute peritonitis, mainly the following several kinds:

　　1. Acute perforation and rupture of abdominal organs

　　Mostly occur in organs with pre-existing lesions. Perforation of hollow organs often occurs suddenly due to the progression of ulcerative or gangrenous lesions, such as acute appendicitis, peptic ulcer, acute cholecystitis, typhoid ulcer, gastric or colorectal cancer, ulcerative colitis, ulcerative intestinal tuberculosis, amebic colitis, diverticulitis, and other perforations leading to acute peritonitis. Substantial organs such as liver and spleen can also rupture due to abscesses or tumors.

　　2. The spread of acute visceral infection

　　For example, acute appendicitis, cholecystitis, pancreatitis, diverticulitis, ascending infection of the female reproductive tract (such as puerperal fever, salpingitis) and other diseases can spread to the peritoneum and cause acute inflammation.

　　3. Acute intestinal obstruction

　　After绞窄性肠梗阻 caused by intussusception, intussusception, incarcerated hernia, mesenteric vascular thrombosis or thrombosis, due to intestinal wall injury, losing the normal barrier function, intestinal bacteria can invade the peritoneal cavity through the intestinal wall, causing peritonitis.

　　4. Abdominal surgical conditions

　　When sharp objects or bullets penetrate the abdominal wall, they can pierce hollow organs or introduce external bacteria into the peritoneal cavity. Abdominal trauma can sometimes cause visceral rupture, leading to acute peritonitis. During abdominal surgery, the outside bacteria can be brought into the peritoneal cavity due to inadequate sterilization; also, due to the carelessness of surgery, local infection can spread, or the suture sites of the stomach, intestines, gallbladder, and pancreas can leak. Sometimes, acute peritonitis can occur due to neglect of aseptic operation during abdominal puncture fluid drainage or peritoneal dialysis.

　　5. Hematogenous disseminated infection

　　It can cause primary acute peritonitis.

　　If peritonitis is not treated quickly and effectively, multiple organ failure will occur rapidly, fluid loss into the abdomen and intestines can lead to severe dehydration and electrolyte disturbance, and the patient may appear with a mask-like expression (Hippocratic facies) and may die within a few days. The following complications may also occur.

　　1. Adult respiratory distress syndrome can also appear rapidly, followed by renal failure, liver failure, and disseminated intravascular coagulation.

　　1. Abdominal abscesses occur in the pelvic area, subphrenic space, left or right colonic peritoneal spaces, subhepatic space, and between intestinal loops. They must be found through clinical examination, ultrasound (useful for examining pelvic or subhepatic abscesses), CT (most effective for examining subphrenic abscesses), and sometimes laparotomy. Percutaneous catheter drainage is often possible under the guidance of ultrasound or CT.

　　The formation of adhesions or bands is a late complication, often causing subsequent obstruction.

　　The main clinical manifestations of acute peritonitis include abdominal pain, tenderness, and muscle tension, often accompanied by nausea, vomiting, bloating, fever, hypotension, tachycardia, dyspnea, and leukocytosis, among other toxic symptoms. Since this disease is often a complication of some abdominal disease, there are often symptoms of the primary disease before and after the onset.

　　1. Acute Abdominal Pain

　　Abdominal pain is the most common and primary symptom, often occurring suddenly, persisting, rapidly spreading, and its nature depends on the type of peritonitis (chemical or bacterial), the extent of inflammation, and the patient's response. When acute perforation of organs such as the stomach, duodenum, and gallbladder causes diffuse peritonitis, the stimulation of peritoneum by digestive fluids results in a sudden and severe pain throughout the abdomen, even leading to so-called peritoneal shock. In a few cases, before secondary bacterial infection occurs, there may be a temporary improvement in the condition, with the pain and peritoneal irritation symptoms subsiding due to the large amount of fluid exudation from the peritoneum, diluting the irritant. After secondary bacterial infection, abdominal pain worsens again. Peritonitis caused by bacterial infection usually has local pain from the primary focus (such as appendicitis, cholecystitis, etc.) before peritonitis, and the pain becomes more gradual and presents as a distending or dull pain when perforation occurs, unlike the severe pain of acute perforation of the stomach or gallbladder. The pain tends to worsen gradually and spread from the focus area to the entire abdomen. The severity of abdominal pain varies from person to person; some patients report extremely severe and persistent pain, while others describe only dull pain or discomfort. In the case of frail or elderly patients, such as severe typhoid patients, there may be no pain during acute perforation.

　　2. Nausea and vomiting

　　Due to peritoneal irritation, nausea and vomiting are reflexive, intermittent, and the vomitus is the contents of the stomach, sometimes with bile; later, due to paralytic intestinal obstruction, vomiting becomes persistent without nausea, and the vomitus is brownish yellow intestinal contents, which may have an unpleasant odor.

　　3. Other symptoms

　　When abdominal peritonitis occurs due to acute perforation of hollow organs, due to peritoneal shock or sepsis, collapse is common, at this time, the body temperature is often lower than normal or close to normal; when collapse improves and peritonitis continues to develop, the body temperature begins to gradually increase. If the primary disease is acute infection (such as acute appendicitis and acute cholecystitis), the body temperature is often higher than the original when acute peritonitis occurs. In cases of acute diffuse peritonitis, due to the large amount of fluid exudation from the peritoneum, the peritoneum and intestinal wall are highly congested and edematous, the atonic intestinal cavity accumulates a large amount of fluid, and factors such as vomiting and dehydration, the effective blood volume and total blood potassium significantly decrease. In addition, due to reduced renal blood flow, the severity of sepsis, and the impairment of heart, kidney, and peripheral vascular function, patients often have hypotension and shock, tachycardia or pulse cannot be felt, and may also have thirst, oliguria or anuria, abdominal distension, and no anal exhaust. Sometimes there are frequent hiccups, the cause of which may be that the inflammation has spread to the diaphragm.

　　The fundamental measure to prevent peritonitis is to treat early and appropriately the abdominal intra-peritoneal inflammatory diseases that may cause peritonitis. Any abdominal surgery, including abdominal puncture, should be strictly performed under sterile conditions. Antibacterial drugs should be administered orally before intestinal surgery to reduce the occurrence of peritonitis.

　　Acute peritonitis is an acute inflammatory lesion of the peritoneum caused by infection, chemical substances (such as gastric juice, intestinal juice, bile, pancreatic juice, etc.), or injury. Among them, bacterial infection is the most common cause. The examination of acute peritonitis mainly relies on laboratory tests.

　　1. The white blood cell count and the proportion of neutrophils are generally significantly increased, and nuclear left shift and toxic granules are common. In patients with severe diffuse peritonitis, due to the large number of white blood cells infiltrating the peritoneal cavity, the number of white blood cells in peripheral blood may not be high, but the proportion of neutrophils is still high. The same is true for the elderly or those with low immune function.

　　2. Urinalysis. Urinalysis is an indispensable preliminary examination in clinical practice. Many kidney diseases can show proteinuria or formed elements in the urine sediment at an early stage. Once abnormal urine is found, it is often the first sign of kidney or urinary tract disease, and also a significant clue to the nature of the pathological process. In recent years, many people emphasize that doctors should perform the urinalysis of patients themselves, which is a general diagnostic method for doctors to discover kidney diseases. Urine becomes concentrated due to dehydration, which can cause protein and casts, and urinary acetone can be positive.

　　3. Blood biochemistry tests can detect acidosis and electrolyte disorders.

　　4. Culturing of peritoneal effusion often yields pathogenic bacteria.

　　5. X-ray examination can show gas under the diaphragm.

　　For patients with acute peritonitis who do not require surgical treatment, if they are preparing for hospital surgery, they should be fasting and water deprivation; for patients whose disease has been controlled, they should eat in small and frequent meals, avoid eating cold and spicy foods, and have regular meals; avoid heavy physical labor; maintain a pleasant mood; and seek a medical consultation as soon as possible when there is abdominal discomfort.

　　For cases diagnosed with primary peritonitis, or for patients with diffuse peritonitis whose course has exceeded 1 to 2 days, and the inflammation has a tendency to localize, or for the elderly and weak, or those with severe toxic symptoms, initial internal medicine support treatment can be given, and the evolution of the condition should be closely observed. Internal medicine support treatment includes:

　　1. Rest in bed, lying in a semi-recumbent position with a slope of 30° to 45° forward to facilitate the flow of inflammatory exudates towards the pelvic cavity and easy drainage. If the shock is severe, a flat lying position should be adopted.

　　No food should be taken and gastrointestinal decompression should be performed.

　　Correct the disorder of body fluids, electrolytes, and acid-base balance. Sufficient fluid should be administered to ensure that the daily urine volume is about 1500ml. It is best to consider the amount of fluid to be infused based on the results of the central venous pressure measurement. In addition, the amount of potassium chloride or sodium salt to be infused should be calculated based on the results of blood electrolyte testing, and the use of sodium bicarbonate and other treatments should be considered based on the blood carbon dioxide binding rate or the pH value of the blood.

　　If possible, intravenous hyperalimentation should be given, or a small amount of plasma or whole blood should be transfused to improve the patient's overall condition and enhance immunity.

　　Antibacterial treatment is the most important internal medicine therapy for acute peritonitis. Generally, secondary peritonitis is often a mixed infection of aerobic bacteria and anaerobic bacteria, so it is advisable to use broad-spectrum antibiotics or use a combination of several antibiotics. If pathogenic bacteria can be obtained and antibiotics can be selected based on drug sensitivity test results, it is better.

　　For those with severe pain or restlessness, if the diagnosis is clear, pethidine, phenobarbital, and other drugs can be used appropriately. In case of shock, active treatment for shock should be carried out.