Most hernias in the human body occur in the abdominal wall and are a result of weaknesses in the wall musculature. There are a multitude of different types, and ventral hernias occur when abdominal cavity contents (usually intestine) protrude through the anterior surface of the abdominal wall. When the abdominal contents get trapped in the musculature, they can get stuck and blood to the protrusion can be lost. This is known as strangulation, and it is a medical emergency.
Pain
Pain is the predominant symptom felt by most patients with a strangulated hernia. The blood supply to the tissue is cut off and the tissue is either slowly dying, or dead.
Peritonitis
The presence of dead tissue can inflame the peritoneum, which is a tissue that lines the inner abdominal wall and covers the abdominal organs. This is known as peritonitis, and is usually an indication for surgery. Symptoms will include a very rigid abdomen that is extremely tender, and possibly decreased urine output. Rebound tenderness can be present, which is pain that is worse when a finger that is pressing down on the abdomen is moved away.
Fever
The dying/dead tissue causes inflammation, of which fever is one of the earliest signs.
Constipation
The abdominal contents that are stuck in the musculature can cause obstruction, meaning no contents proximal to it can be passed to the rectum for defecation.
Nausea and Vomiting
The obstruction caused by the hernia can also cause whatever contents that are proximal to the obstruction to be sent back up the other way, out the patient's mouth. The vomit will usually have bile, a sign that the contents are coming from the intestine, which is not usually the case with normal vomiting.
References
- "Clinical Procedures in Emergency Medicine, 5th edition;" Roberts; 2009
- "Sabiston Textbook of Surgery, 18th edition;" Townsend; 2007
- Mayo Clinic: Peritonitis
