Appendicitis

( Written and Viva Question of Final Professional MBBS of Bangladesh )

Appendicitis initially causes intermittent periumbilical pain. Gradually the pain becomes constant in the right lower quadrant as peritoneal inflammation develops.

Appendicitis

About 10% of the population will develop acute appendicitis during their lifetime. The disorder most commonly develops in the teens and twenties. Appendicitis is caused by appendiceal obstruction, mucosal ischemia, infection, and perforation.

Diagnosis of appendicitis

Clinical presentation. Early appendicitis is characterized by progressive midabdominal

discomfort, unrelieved by the passage of stool or flatus. Ninety percent of patients are anorexic, 70% have nausea and vomiting, and 10% have diarrhea. The pain migrates to the right lower quadrant after 4-6 hours. Peritoneal irritation is associated with pain on movement.

Physical examination

1. Mild fever and tachycardia are common in appendicitis.

2. Abdominal palpation should begin away from the right lower quadrant. Point tenderness over the right lower quadrant is the most definitive finding. Pain in the right lower quadrant during palpation of the left lower quadrant (Rovsing's sign) indicates peritoneal irritation. The degree of direct tenderness and rebound tenderness should be assessed. The degree of muscular resistance to palpation reflects the severity of inflammation. Cutaneous hyperesthesia often overlies the region of maximal tenderness.

3. Psoas sign. With the patient lying on the left side, slow extension of the right hip causes local

irritation and pain. A positive psoas sign indicates retroperitoneal inflammation.

4. Obturator sign. With the patient supine, passive internally rotation of the flexed right hip causes hypogastric pain.

5. Rectal examination should evaluate the presence of localized tenderness or an inflammatory

mass in the pelvis.

6. Pelvic examination, in women, should be completed to assess cervical motion tenderness

and to evaluate the presence of adnexal tenderness.

7. The appendix usually is found at McBurney's point (two-thirds of the distance from the

umbilicus to the anterior superior iliac spine).

8. Diarrhea, urinary frequency, pyuria, or microscopic hematuria may suggest a retrocecal

appendix, causing irritation of adjacent structures.

Laboratory evaluation

1. Leukocyte count greater than 11,000 cells/ul with polymorphonuclear cell predominance is

common in children and young adults.

2. Urinalysis is abnormal in 25% of patients with appendicitis. Pyuria, albuminuria, and hematuria are common. Bacteria suggest urinary tract infection. Hematuria suggests urolithiasis.

3. Serum pregnancy test should be performed in women of childbearing age. A positive test

suggests an ectopic pregnancy.

Radiologic evaluation

Abdominal x-rays. An appendicolith can be seen in only one-third of children and one-fifth of

adults with appendicitis. An appendiceal mass can indent the cecum, and tissue edema can

cause loss of peritoneal fat planes around the psoas muscle and kidney.

Ultrasonography. Findings associated with appendicitis include wall thickening, luminal

distention, lack of compressibility, abscess formation, and free intraperitoneal fluid.

Differential diagnosis

Gastrointestinal diseases

1. Gastroenteritis is characterized by nausea, emesis prior to the onset of abdominal pain,

malaise, fever, and poorly localized abdominal pain and tenderness. The WBC count is less

frequently elevated.

2. Meckel's diverticulitis may mimic appendicitis.

3. Perforated peptic ulcer disease, diverticulitis, and cholecystitis can present similarly to

appendicitis.

Urologic diseases

1. Pyelonephritis is associated with high fever, rigors, and costovertebral pain and tenderness.

Diagnosis is confirmed by urinalysis.

2. Ureteral colic. Renal stones cause flank pain radiating into the groin. Tenderness is usually

minimal and hematuria is present. The intravenous pyelogram is diagnostic.

Gynecologic diseases

1. Pelvic inflammatory disease (PID). The onset of pain in PID usually occurs within 7 days of

menstruation. Cervical motion tenderness, a white vaginal discharge, and bilateral adnexal

tenderness suggest PID. Ultrasound can help distinguish PID from appendicitis

2. Ectopic pregnancy. A pregnancy test should be performed in all female patients of childbearing age presenting with abdominal pain. Ultrasonography is diagnostic.

3. Ovarian cysts can cause sudden pain by enlarging or rupturing.The cysts are detected by

transvaginal ultrasonography.

4. Ovarian torsion. The ischemic ovary often can be palpated on bimanual pelvic examination.

The diagnosis is confirmed by ultrasonography

Appendectomy Surgical Technique

I. Preoperative preparation

A. Intravenous isotonic fluid replacement should be initiated to achieve good urinary output and to correct electrolyte abnormalities. Nasogastric suction should be initiated if the patient is vomiting or if peritonitis is present.

B. Fever is treated with acetaminophen. Broadspectrum antibiotic coverage is initiated

preoperatively. Antibiotic therapy should cover gram-negative and anaerobic organisms.

Surgical technique

A. After induction of anesthesia, place an incision over any appendiceal mass if palpable. If no mass is present, make a transverse skin incision over McBurney's point, located two thirds of the way between the umbilicus and anterior superior iliac spine. A transverse incision allows easy extension medially for greater exposure. Diffuse peritonitis should be explored through a midline incision.

B. Incise the subcutaneous tissues in the line of the transverse incision, and incise the external oblique aponeurosis in the direction of its muscle fibers.Spread the muscle with a Peon hemostat.

C. Incise the internal oblique fascia and spread the incision in the direction of its fibers. Sharply incise the transversus abdominis muscle, transversalis fascia, and peritoneum. Note the presence and characteristics of peritoneal fluid, and send purulent fluid for Gram's stain and aerobic and anaerobic culture.

D. Identify the base of the cecum by the converging taeniae coli, and raise the cecum, exposing the base of the appendix. Hook an index finger around the appendix, and gently break down any adhesions to adjacent tissues. Use gauze packing to isolate the inflamed appendix, and stabilize the appendix with a Babcock forceps.

E. Apply two clamps to the mesoappendix, then divide the mesoappendix between the clamps, then firmly ligate below the clamps with 000 silk or polyglycolic acid sutures. Apply an encircling purse-string suture of 000 silk at the end of the cecum about 0.8 cm from the base of the appendix. Place a hemostatatthe proximal base of the appendix,and crush the appendix. Remove the hemostat and reapply it to the appendix distal to the crush. Use an 0 chromic catgut suture to ligate the crushed area below the hemostat.

F. Transect the appendix against the clamp. Invert the stump into the cecum with the purse-string suture, and tie the purse-string suture, burying the stump. Irrigate the peritoneum with normal saline, and examine the mesoappendix and abdominal wall for hemostasis. Close the peritoneum with continuous 000 catgut suture.

G. Close the internal oblique and transversus abdominis with interrupted O chromic catgut. Close the external oblique as a separate layer. Close the skin and subcutaneous tissues. A soft rubber Penrose drain should be placed if perforation has occurred. It should be brought out through a stab incision in the lateral abdominal wall or through the lateral end of the incision.

H. If the appendix is normal on inspection (5-20% of explorations), it should be removed, and alternative diagnoses should be investigated. The cecum, sigmoid colon, and ileum should be inspected, and mesenteric lymphadenopathy should be sought. Ovaries and fallopian tubes should be inspected for PID, ruptured cysts, or ectopic pregnancy. Bilious peritoneal fluid suggests perforation of a peptic ulcer or the gallbladder.

Intravenous antibiotics

A. Antibiotic prophylaxis should include coverage for bowel flora, including aerobes and anaerobes.Cefotetan , 1 gm IV q12h, or piperacillin/tazobactam , 4.5 gm IV q6h, should be given before the operation and discontinued after two doses postoperatively.

B. If perforation has occurred, IV antibiotics should be continued for 5-10 days. Check culture on the third postoperative day and change antimicrobials if a resistant organism is present.