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I. PATHOPHSIOLOGY

A. DESCRIPTION

The pathophysiology of appendicitis is the constellation of processes that leads to the development of acute appendicitis from a normal appendix. The main thrust of events leading to the development of acute appendicitis lies in the appendix developing a compromised blood supply due to obstruction of its lumen and becoming very vulnerable to invasion by bacteria found in the gut normally.

B. RISK FACTORS

1. SEX

The incidence of appendicitis is approximately 1.4 times greater in men than in women. The incidence of primary appendectomy is approximately equal in both sexes.

2. AGE

Incidence of appendicitis gradually rises from birth, peaks in the late teen years, and gradually declines in the geriatric years. The median age at appendectomy is 22 years.

The emergency department clinician must maintain a high index of suspicion in all age groups.

3. CULTURE/ DIET

Incidence of appendicitis is lower in cultures with a higher intake of dietary fiber. Dietary fiber is thought to decrease the viscosity of feces, decrease bowel transit time, and discourage formation of fecaliths, which predispose individuals to obstructions of the appendiceal lumen.

People whose diet is low in fiber and rich in refined carbohydrates have an increased risk of getting appendicitis.

4. HEREDITARY

A particular position of the appendix, which predisposes it to infection, runs in certain families. Having a family history of appendicitis may increase a child's risk for the illness.

5. SEASONAL VARIATION

Most cases of appendicitis occur in the winter months - between the months of October and May.

6. INFECTIONS

Gastrointestinal infections such as Amebiasis, Bacterial Gastroenteritis, Mumps, Coxsackievirus B and Adenovirus can predispose an individual to Appendicitis.

C. COMMON SIGNS AND SYMPTOMS

1. abdominal pain usually

occurs suddenly, often causing a person to wake up at night occurs before other symptoms begins near the belly button and then moves lower and to the right is new and unlike any pain felt before gets worse in a matter of hours gets worse when moving around, taking deep breaths, coughing, or sneezing

2. SIGNS UPON PHYSICAL EXAM THAT MAY INDICATE APPENDICITIS

Guarding. Guarding occurs when a person subconsciously tenses the abdominal muscles during an examination. Voluntary guarding occurs the moment the doctor’s hand touches the abdomen. Involuntary guarding occurs before the doctor actually makes contact.

Rebound tenderness. A doctor tests for rebound tenderness by applying hand pressure to a patient’s abdomen and then letting go. Pain felt upon the release of the pressure indicates rebound tenderness. A person may also experience rebound tenderness as pain when the abdomen is jarred—for example, when a person bumps into something or goes over a bump in a car.

Rovsing’s sign. A doctor tests for Rovsing’s sign by applying hand pressure to the lower left side of the abdomen. Pain felt on the lower right side of the abdomen upon the release of pressure on the left side indicates the presence of Rovsing’s sign.

Psoas sign. The right psoas muscle runs over the pelvis near the appendix. Flexing this muscle will cause abdominal pain if the appendix is inflamed. A doctor can check for the psoas sign by applying resistance to the right knee as the patient tries to lift the right thigh while lying down.

Obturator sign. The right obturator muscle also runs near the appendix. A doctor tests for the obturator sign by asking the patient to lie down with the right leg bent at the knee. Moving the bent knee left and right requires flexing the obturator muscle and will cause abdominal pain if the appendix is inflamed.

3. Other symptoms of appendicitis may include

loss of appetite nausea vomiting constipation or diarrhea inability to pass gas a low-grade fever that follows other symptoms abdominal swelling the feeling that passing stool will relieve discomfort

Predisposing factors-Age-Gender-Diet-Hereditary-Seasonal variation-Infections

Precipitating factors-Poor hygiene-Gender

D. SCHEMATIC DIAGRAM

Fever,

Obstruction of the appendix(by fecalith, lymph

node, tumour, foreign objects)

Inflammation

Increase intraluminal pressure

Distention of the Appendix

Decrease venous drainage

Blood flow and oxygen restriction to the appendix

Bacterial Invasion of the Blood wall

Necrosis of the appendix