Peritonitis - Acute Inflammatory Intestinal Disorders

PERITONITIS

Peritonitis is inflammation of the peritoneum, the serous mem-brane lining the abdominal cavity and covering the viscera. Usually, it is a result of bacterial infection; the organisms come from diseases of the GI tract or, in women, from the internal reproductive organs. Peritonitis can also result from external sources such as injury or trauma (eg, gunshot wound, stab wound) or an inflammation that extends from an organ outside the peritoneal area, such as the kid-ney. The most common bacteria implicated are Escherichia coli,Klebsiella, Proteus, and Pseudomonas. Inflammation and paralyticileus are the direct effects of the infection. Other common causes of peritonitis are appendicitis, perforated ulcer, diverticulitis, and bowel perforation (Fig. 38-4). Peritonitis may also be associated with abdominal surgical procedures and peritoneal dialysis

Pathophysiology

Peritonitis is caused by leakage of contents from abdominal or-gans into the abdominal cavity, usually as a result of inflamma-tion, infection, ischemia, trauma, or tumor perforation. Bacterial proliferation occurs. Edema of the tissues results, and exudation of fluid develops in a short time. Fluid in the peritoneal cavity be-comes turbid with increasing amounts of protein, white blood cells, cellular debris, and blood. The immediate response of the intestinal tract is hypermotility, soon followed by paralytic ileus with an accumulation of air and fluid in the bowel.

Clinical Manifestations

Symptoms depend on the location and extent of the inflamma-tion. The early clinical manifestations of peritonitis frequently are the symptoms of the disorder causing the condition. At first, a diffuse type of pain is felt. The pain tends to become constant, localized, and more intense near the site of the inflammation. Movement usually aggravates it. The affected area of the abdomen becomes extremely tender and distended, and the muscles become rigid. Rebound tenderness and paralytic ileus may be present. Usually, nausea and vomiting occur and peristalsis is diminished. The temperature and pulse rate increase, and there is almost always an elevation of the leukocyte count.

Assessment and Diagnostic Findings

The leukocyte count is elevated. The hemoglobin and hematocrit levels may be low if blood loss has occurred. Serum electrolyte stud-ies may reveal altered levels of potassium, sodium, and chloride.

An abdominal x-ray is obtained, and findings may show air and fluid levels as well as distended bowel loops. A CT scan of the abdomen may show abscess formation. Peritoneal aspiration and culture and sensitivity studies of the aspirated fluid may reveal infection and identify the causative organisms.

Complications

Frequently, the inflammation is not localized and the whole ab-dominal cavity becomes involved in a generalized sepsis. Sepsis is the major cause of death from peritonitis. Shock may result from septicemia or hypovolemia. The inflammatory process may cause intestinal obstruction, primarily from the development of bowel adhesions.

The two most common postoperative complications are wound evisceration and abscess formation. Any suggestion from the pa-tient that an area of the abdomen is tender or painful or “feels as if something just gave way” must be reported. The sudden oc-currence of serosanguineous wound drainage strongly suggests wound dehiscence.

Medical Management

Fluid, colloid, and electrolyte replacement is the major focus of medical management. The administration of several liters of an iso-tonic solution is prescribed. Hypovolemia occurs because massive amounts of fluid and electrolytes move from the intestinal lumen into the peritoneal cavity and deplete the fluid in the vascular space.

Analgesics are prescribed for pain. Antiemetics are adminis-tered as prescribed for nausea and vomiting. Intestinal intubation and suction assist in relieving abdominal distention and in pro-moting intestinal function. Fluid in the abdominal cavity can cause pressure that restricts expansion of the lungs and causes res-piratory distress. Oxygen therapy by nasal cannula or mask can promote adequate oxygenation, but airway intubation and ven-tilatory assistance occasionally are required.

Massive antibiotic therapy is usually initiated early in the treatment of peritonitis. Large doses of a broad-spectrum anti-biotic are administered intravenously until the specific organism causing the infection is identified and the appropriate antibiotic therapy can be initiated.

Surgical objectives include removing the infected material and correcting the cause. Surgical treatment is directed toward exci-sion (ie, appendix), resection with or without anastomosis (ie, in-testine), repair (ie, perforation), and drainage (ie, abscess). With extensive sepsis, a fecal diversion may need to be created.

Nursing Management

Ongoing assessment of pain, vital signs, GI function, and fluid and electrolyte balance is important. The nurse reports the nature of the pain, its location in the abdomen, and any shifts in location. Ad-ministering analgesic medication and positioning the patient for comfort are helpful in decreasing pain. The patient is placed on the side with knees flexed; this position decreases tension on the ab-dominal organs. Accurate recording of all intake and output and central venous pressure assists in calculating fluid replacement. The nurse administers and monitors closely intravenous fluids.

Signs that indicate that peritonitis is subsiding include a de-crease in temperature and pulse rate, softening of the abdomen, return of peristaltic sounds, passing of flatus, and bowel move-ments. The nurse increases fluid and food intake gradually and reduces parenteral fluids as prescribed. A worsening clinical con-dition may indicate a complication, and the nurse must prepare the patient for emergency surgery.

Drains are frequently inserted during the surgical procedure, and the nurse must observe and record the character of the drainage postoperatively. Care must be taken when moving and turning the patient to prevent the drains from being dislodged. It is also important for the nurse to prepare the patient and family for dis-charge by teaching the patient to care for the incision and drains if the patient will be sent home with the drains still in place.