Acute appendicitis: a disease severity score for the acute care surgeon.

BACKGROUND

Analogous to organ injury scales developed for trauma, a scoring system is needed for acute care surgery. The purpose of this study was to develop a disease severity score (DSS) for acute appendicitis, the most common surgical emergency.

METHODS

A panel of acute care surgery experts reviewed the literature and developed a DSS for acute appendicitis as follows: grade 1, inflamed; Grade 2, gangrenous; Grade 3, perforated with localized free fluid; Grade 4, perforated with a regional abscess; and Grade 5, perforated with diffuse peritonitis. We applied the DSS to 1,000 consecutive patients undergoing appendectomy from 1999 to 2009 and examined its association with outcomes (mortality, length of hospital stay, incidence of in-hospital, and postdischarge complications). Of the 1,000 patients, 82 were excluded owing to negative or interval appendectomy or advanced end-stage renal disease.

RESULTS

Among 918 eligible patients, the DSS distribution was Grade 1 at 62.4%, Grade 2 at 13.0%, Grade 3 at 18.7%, Grade 4 at 4.4%, and Grade 5 at 1.5%. Statistical analyses indicated a stepwise risk increase in adverse outcomes with higher DSS grades (c statistics ≥ 0.75 for all outcomes). Covariates (age, sex, and type of surgical access) did not add to the predictive power of DSS.

CONCLUSION

Based on this single-institution study, the proposed appendicitis DSS seems to be a useful tool. This DSS can inform future, national efforts, which can build on the knowledge provided by the present investigation. This DSS may be useful for comparing therapeutic modalities, planning resource use, improving programs, and adjusting reimbursement

LEVEL OF EVIDENCE: Epidemiologic study, level III.