The ‘acute abdomen‘ is characterized as a sudden onset of severe abdominal pain lasting less than 24 hours. This condition constitutes a surgical emergency, demanding urgent attention and treatment. An acute abdomen can stem from various underlying issues, including infection, inflammation, vascular occlusion, or obstruction. Patients typically present with abrupt abdominal pain accompanied by nausea or vomiting. Most individuals experiencing an acute abdomen appear acutely ill.

Causes

Common causes of an acute abdomen include:

• Acute appendicitis

• Acute peptic ulcer and its complications

• Acute cholecystitis

• Acute pancreatitis

• Acute intestinal ischemia

• Acute diverticulitis

• Ectopic pregnancy with tubal rupture

• Ovarian torsion

• Acute peritonitis (including hollow viscus perforation)

• Acute ureteric colic

• Bowel volvulus

• Bowel obstruction

• Acute pyelonephritis

• Adrenal crisis

• Biliary colic

• Abdominal aortic aneurysm

• Hemoperitoneum

• Ruptured spleen

• Kidney stone

• Sickle cell anemia

Peritonitis

Peritonitis is an inflammation of the peritoneum, the tissue that lines the inner wall of the abdomen and covers and supports most abdominal organs. Peritonitis is most often caused by bacterial or fungal infection.

If left untreated, peritonitis can rapidly spread into the bloodstream (sepsis) and to other organs, potentially leading to multiple organ failure and death. Therefore, if any symptoms of peritonitis develop—the most common being severe abdominal pain—it is essential to seek prompt medical evaluation and treatment to prevent potentially fatal complications.

Symptoms of Peritonitis

The initial symptoms of peritonitis typically include poor appetite, nausea, and a dull abdominal ache that quickly intensifies into persistent, severe abdominal pain, exacerbated by any movement.

Other signs and symptoms associated with peritonitis may include:

• Abdominal tenderness or distention

• Chills

• Fever

• Fluid accumulation in the abdomen

• Significantly reduced or absent urine output

• Difficulty passing gas or having a bowel movement

• Vomiting

Causes of Peritonitis

The two main types of peritonitis are:

1. Primary spontaneous peritonitis: An infection that develops directly within the peritoneum.

2. Secondary peritonitis: Usually develops when an injury or infection in the abdominal cavity allows infectious organisms to enter the peritoneum.

The most common risk factors for primary spontaneous peritonitis include:

• Liver disease with cirrhosis: Such conditions often lead to a buildup of abdominal fluid (ascites) that can become infected.

• Kidney failure requiring peritoneal dialysis: This technique, which involves implanting a catheter into the peritoneum, is used to remove waste products from the blood in individuals with kidney failure.

Common causes of secondary peritonitis include:

• A ruptured appendix, diverticulum, or stomach ulcer

• Digestive diseases such as Crohn’s disease and diverticulitis

• Pancreatitis

• Pelvic inflammatory disease

• Perforations of the stomach, intestine, gallbladder, or appendix

• Surgery

• Trauma to the abdomen, such as injuries from a knife or gunshot wound

Noninfectious causes of peritonitis include irritants like bile, blood, or foreign substances in the abdomen, such as barium.

Diagnosis of peritonitis

Given that peritonitis can swiftly lead to potentially fatal complications like sepsis and septic shock (which cause a massive drop in blood pressure, organ failure, and death), a rapid diagnosis followed by appropriate treatment is crucial.

• Physical examination: Assessing for tension and tenderness in the abdomen.

• Blood and urine tests.

• Imaging tests: Such as X-rays and CT scans.

• Exploratory surgery.

• Paracentesis: A procedure where fluid is withdrawn from the abdominal cavity to check for infections (relevant for primary spontaneous peritonitis).

Treatments for Peritonitis

• If diagnosed with peritonitis, the patient is admitted to a hospital.

• Immediate administration of intravenous antibiotics or antifungal medications is initiated to treat the infection.

• Additional supportive treatments will be necessary if organ failure due to sepsis develops as a complication of the infection. Such treatments may include intravenous fluids, drugs to maintain blood pressure, and nutritional support.

• For peritoneal dialysis-associated peritonitis, medications may be injected directly into the peritoneal tissue, a strategy that some studies have reported to be more effective than intravenous medications.

• Emergency surgery is required, especially if peritonitis is caused by conditions such as appendicitis, a perforated stomach ulcer, or diverticulitis.

• During hospitalization, the patient will be closely monitored for signs of sepsis and septic shock, which usually necessitate immediate transfer to an intensive care unit.

Preventing Peritonitis

• Early administration of antibiotics in cases of cirrhosis and ascites to prevent infection.

• If receiving peritoneal dialysis, the risk of peritonitis can be lowered by adhering to these guidelines:

  • Thoroughly wash hands, including between fingers and under fingernails, before touching the catheter.

  • Wear a mouth/nose mask during exchanges.

  • Observe proper sterile exchange technique.

  • Apply an antibiotic cream to the catheter exit site daily.

INTESTINAL OBSTRUCTION

This is a surgical emergency.

Symptoms of intestinal obstruction

Intestinal obstruction leads to a wide array of uncomfortable symptoms, including:

• Severe bloating

• Abdominal pain

• Decreased appetite

• Nausea

• Vomiting

• Inability to pass gas or stool

• Constipation

• Diarrhea

• Severe abdominal cramps

• Abdominal swelling

Some symptoms may vary depending on the obstruction’s location and duration. For instance, vomiting is an early sign of small intestine obstruction and can also occur with an ongoing large intestine obstruction.

A partial obstruction can result in diarrhea, whereas a complete obstruction leads to an inability to pass gas or stool.

Intestinal obstruction can also cause severe infection and inflammation of the abdominal cavity, known as peritonitis. This occurs when a segment of the intestine ruptures, leading to fever and escalating abdominal pain. This condition is a life-threatening emergency requiring surgical intervention.

Causes

Mechanical causes

Mechanical obstructions involve a physical blockage within the intestine. In the small intestine, this can be due to:

• Adhesions: Fibrous tissue that can develop after abdominal or pelvic surgery or severe inflammation.

• Volvulus: Twisting of the intestines.

• Intussusception: A “telescoping,” or pushing, of one segment of the intestine into the next section.

• Malformations of the intestine: Often present in newborns, but can also occur in children and teenagers.

• Tumors within the small intestine.

• Gallstones: Although they rarely cause obstructions.

• Swallowed objects: Especially in children.

• Hernias: Involve a portion of the intestine protruding outside the body or into another body part.

• Inflammatory bowel disease: Such as Crohn’s disease.

Mechanical obstructions can also block the colon, or large intestine. This can be due to:

• Impacted stool

• Adhesions from pelvic infections or surgeries

• Ovarian cancer

• Colon cancer

• Meconium plug in newborns (meconium being the first stool passed by babies)

• Volvulus and intussusception

• Diverticulitis: The inflammation or infection of bulging pouches in the intestine.

• Stricture: A narrowing in the colon caused by scarring or inflammation.

Nonmechanical obstruction

The small and large intestines normally operate through a coordinated system of movement. If something disrupts these coordinated contractions, it can lead to a functional intestinal obstruction.

Causes include:

• Abdominal or pelvic surgery

• Infections, such as gastroenteritis or appendicitis

• Certain medications, including opioid pain medications

• Electrolyte imbalances

Intestinal pseudo-obstruction

This can be caused by:

• Parkinson’s disease, multiple sclerosis, and other nerve and muscle disorders.

• Hirschsprung’s disease: A disorder characterized by a lack of nerves in sections of the large intestine.

• Disorders that cause nerve injury, such as diabetes mellitus.

• Hypothyroidism: An underactive thyroid gland.

Intestinal obstruction in infants

Intestinal obstruction in infants typically arises from infections, organ diseases, and reduced blood flow to the intestines (strangulation).

Intussusception is most common in children aged 2 years and younger. This occurs when one part of their bowel collapses or slides into another part, resulting in intestinal blockage.

Symptoms:

• Abdominal swelling

• Drawing knees up to the chest

• Appearing excessively drowsy

• Having a fever

• Grunting in pain

• Passing stools that appear to contain blood, known as a “currant jelly stool”

• Very loud crying

• Vomiting, particularly yellow-green, bile-like vomiting

• Displaying signs of weakness

Diagnosis

• Physical examination: Using a stethoscope to listen to bowel sounds.

• Blood tests: For blood counts, liver and kidney function, and electrolyte levels.

• X-rays.

• CT scan.

• Colonoscopy: A flexible lighted tube used by the doctor to examine the large intestine.

• Enema with contrast.

Treatment

Treatment depends on the obstruction’s location and severity.

• Complete bed rest.

• Intravenous (IV) fluids are administered to treat dehydration, correct electrolyte imbalances, and prevent shock during surgery.

• Catheterization to drain urine.

• Bowel rest: Means the patient will be given nothing to eat, or only clear liquids, during that time.

• A tube may need to be passed through the nose and down into the throat, stomach, and intestines to relieve pressure, swelling, and vomiting.

• Surgery will be required if these measures fail or if symptoms worsen.

• Antibiotics to reduce infection.

• Anti-nausea medicines to prevent vomiting.

• Pain relievers.

Complications

Treatment is essential to mitigate complications such as:

• Dehydration

• Electrolyte imbalances

• Perforation: A hole that forms in the intestines, leading to infections.

• Kidney failure

If the obstruction impedes blood flow to a segment of the intestine, this can lead to:

• Intestinal perforations

• Bleeding

• Intestinal gangrene (tissue death)

• Infection

• Sepsis: A life-threatening bloodstream infection.

• Multiple organ failure