[An useful classification for acute appendicitis]

To analyze clinical aspects of acute appendicitis at a teaching hospital, and to present a simple classification for acute appendicitis according to surgical findings, a classification that will indicate what postoperative treatment should be.

The study included 3,112 adult patients who had undergone surgery between September 1994 and February 2000 and who had been diagnosed preoperatively with acute appendicitis. Faced with the need to simplify description of surgical findings and to relate them to treatment, the following classification was instituted: Grade 0: No appendicitis; incidental appendectomy was carried out and antimicrobians were stopped. Grade Ia: Oedematous, ingurgitated appendix. Grade Ib: Abscessed or phlegmonous appendix, presents fibrin membranes and seropurulent liquid around appendix. Grade Ic: Necrosed appendix with no perforation. In these grades, there is very little or no presence of bacteria in periappendicular liquid or in fibrin membranes. Hence, treatment consisted of appendectomy and perioperative antimicrobians (metronidazol 500 mg and amikacine 500 mg within 2 h prior to surgery, followed by two further doses every 8 h postoperatively). Grade II: Perforated appendix with localized abscess. Treatment consisted of appendectomy and antimicrobians begun preoperatively and continuing for 3 days. A Saratoga or Penrose drain was inserted if internal tissue bed remaining after excision was raw or bloody, and might have predisposed to collection of fluid. Grade III: Complicated appendicitis with generalized peritonitis. In these cases, appendectomy was carried out with lavage to abdominal cavity. Antimicrobians were administered beginning preoperatively and were continued until patient's general condition was good, the patient had remained afebrile for 48 h and white cell count had fallen.

Patients ranged in age from 16 to 83 years, with 62% of patients men and 38%, women. Grade I appendicitis was found to be the most common, affecting 74% of patients. Hospital stay for grade I appendicitis was 2 days; for grade II appendicitis, from 2 to 7 days; and for grade III appendicitis, from 3 to 14 days. No significant difference was noted in presence of surgical wound infection among grade I appendicitis cases, incidence being 1.1%. In grade II appendicitis cases, incidence was 17.1% and 36% in grade III cases.

Classification of acute appendicitis as herein proposed made it possible to standardize management and treatment carried out and to predict possible complications.