FACTS

Acute appendicitis is the most common surgical emergency of the abdomen

Appendectomy is one of the most frequently performed surgical procedures

FACTS

Mortality rate from perforated appendicitis:

near certain death a century ago

10-20 per cent 50 years ago

5 per cent during the 1960s

1 per cent or less from the 1970s to the present

FACTS“Rates of unnecessary appendectomies

and perforation have remained relatively high despite gaining a century of clinical experience with acute appendicitis”

“The dramatic expansion of diagnostic testing options and the introduction of innovative surgical approaches during the last decade has actually caused even more debate and disagreement than resolution of issues.”

OPERATIONAL DEFINITIONS

Uncomplicated Appendicitis: Includes the acutely inflamed,

phlegmonous, suppurative, or mildly inflamed appendix with or without peritonitis

OPERATIONAL DEFINITIONS

Complicated Appendicitis: Includes gangrenous appendicitis,

perforated appendicitis, localized purulent collection at operation, generalized peritonitis and periappendiceal abscess

OPERATIONAL DEFINITIONS

Equivocal Appendicitis: A patient with right lower

quadrant abdominal pain who presents with an atypical history and physical examination and the surgeon cannot decide whether to discharge or to operate on the patient

Adult size 9 cms length ; 1-3 mm lumen

Base constant = confluence of taenia coli

Blood supply – appendicular branch of ileocolic artery

Lymphatics – follows the blood supply

HISTOLOGIC FEATURES

- Muscular layer not well defined

- Lymphoid aggregates in submucosa and mucosa

- Mucosa is like colon, but irregular shaped crypts

PHYSIOLOGY

-Serotonin – mediates pain arising from non inflamed appendix

- “ carcinoid tumors”

- Immune surveillance

- Secretes mucin, fluid & proteolytic enzymes

DISEASES OF THE VERMIFORM APPENDIX

I. Acute appendicitis

Etiology & Pathogenesis:

A.Role of environmental: Diet and Hygiene

Western Diet (Low fiber, High fat)Change in motility, flora,

lumen – fecalith formation

B. Role of obstruction

- anatomical

- hyperplasia of lymphoid

- neoplasm/foreign body

Sequence of events:

Increase mucus & fluids inc intraluminal pressure – obstructed outflow of blood (venules) & lymph

inc P appendiceal wall obstructs arterial supply mucosal ischemia, inflammation, stasis, necrosis of muscularis

PERFORATION

Observation:

Impacted fecalith – no local inflammation (50%)

C. Role of colonic flora

- 60% Anaerobes – inflammed AP

- 25% Anaerobes – non-inflammed AP

Lumen – source of microorganism (E.coli/Bacteroides)

Pieper et al – inc antibody titer to Bacteriodes Gangrene & perforation

NATURAL HISTORY

Temple et al(1995) Prospective study Ann. Surgery

- 20% perforation < 24 hrs after onset of symptoms

- 1 patient <10 hrs

- average time to perforate 64h

CLINICAL PRESENTATIONS:

Symptoms:

Abdominal pain – crampy colicky, initial response of muscularis of appendix to obstruction

Vomiting, nausea, loss of appetite

CLINICAL PRESENTATIONS:

Signs:

Tenderness – local inflammatory response; tip of appendix touching parietal peritoneum

Fever rarely occurs (38.2oC)

3 CLASSIC MANEUVERS:

• Rovsing sign – peritoneal irritation

• Psoas sign – irritation of psoas muscle

• Obturator sign – irritation of obturator muscle

“OVERALL CLINICAL PICTURE COUNTS”

Laboratory:

Leukocytes count – serial

Urinalysis – exclude ureteral stone/UTI

Liver enzymes/amylase – R/O HBT dse

BHCG – Pregnancy

Imaging studies:

• Plain film- abnormal gas pattern

-(+) fecalith/ rule out other dse.

• Graded compression USG- A-P> 6mm

- sensitivity (55-96%), spec (85-98%)

• CT scan – dilated AP(>5cm),thickened

- wall,(92% sensitive, 94% spec)

BHCG – Pregnancy

Imaging studies

Alvarado scale for the diagnosis of AP

Migration of pain(1),anorexia(1), N/V(1)

RLQ pain (2),rebound (1),fever (1)

Leukocytosis (2), left shift (1)

• 9-10 = almost certain/no labs

• 7-8 = high likelihood

• 5-6 =compatible with but not diagnostic

Acute appendicitis is essentially a clinical diagnosis; there is no laboratory or radiologic test yet devised that is 100% diagnostic of this condition

EVALUATION

Hx and PE – serial PE, one examiner, rectal exam, speculum, bimanual examination, urinalysis, pregnancy test

MANAGEMENT:

a. preop – fluids/antibiotics (2nd gen)

b. Operative – open/laparoscopy

c. Postop - antibiotics

COMPLICATIONS

• Perforation

• Abscess formation

• Intestinal obstruction

• Bacteremia

• Sepsis

• Fistula

• Liver abscess

• Pyelophlebitis

Differential diagnosis:

Acute mesenteric adenitis, AGE, dse of male urogenital system

Meckel’s diverticulitis, intessusception, perforated peptic ulcer, colonic lesion, epiploic appendagitis

UTI, gynecologic dse, Henoch-Schonlein purpura

Special consideration:

Lifetime risk- 12%( males )

25%( females )

Mean age – 31.3 y/o

2nd- 4th decade of life

Rate of misdiagnosis- 15% (higher in females, 22.3 vs 9.3%)

Negative appendectomy women- 23.2%

Special consideration:

Advance age – 50-70% perforation

Use of imaging modalities like CT scan

Pregnancy – location of appendix base on AOG

- ultrasound

II. Neoplasm

> 0-5% incidence

> AdenoCA, Cystic neoplasm, carcinoid, mets, lymphoma, leiomyosarcoma

> Treatment: Right hemicolectomy

> 5 yr. survival- 55%