Derivation and validation of a novel severity classification for intraoperative adverse events

Haytham M.A. Kaafarani, Michael N. Mavros, John Hwabejire, Peter Fagenholz, Daniel D. Yeh, Marc Demoya, David R. King, Hasan B. Alam, Yuchiao Chang, Matthew Hutter, Donna Antonelli, Alice Gervasini, George C. Velmahos

Research output: Contribution to journalArticlepeer-review

38 Scopus citations


Background There is currently no systematic approach to evaluating the severity of intraoperative adverse events (iAEs). Study Design A 3-phase project was designed to develop and validate a novel severity classification scheme for iAEs. Phase 1 created the severity classification using a modified Delphi process. Phase 2 measured the classification's internal consistency by calculating inter-rater reliability among 91 surgeons using standardized iAEs scenarios. Phase 3 measured the classification's construct validity by testing whether major iAEs (severity class ≤3) correlated with worse 30-day postoperative outcomes compared with minor iAEs (severity class <3). This was achieved by creating a matched database using American College of Surgeons NSQIP and administrative data, querying for iAEs using the Patient Safety Indicator #15 (Accidental Puncture/Laceration), and iAE confirmation by chart review. Results Phase 1 resulted in a 6-point severity classification scheme. Phase 2 revealed an inter-rater reliability of 0.882. Of 9,292 patients, phase 3 included 181 confirmed with iAEs. All preoperative/intraoperative variables, including demographics, comorbidities, type of surgery performed, and operative length, were similar between patients with minor (n = 110) vs major iAEs (n = 71). In multivariable logistic analysis, severe iAEs correlated with higher risks of any postoperative complication (odds ratio [OR] = 3.8; 95% CI, 1.9-7.4; p < 0.001), surgical site infections (OR = 3.7; 95% CI, 1.7-8.2; p = 0.001), systemic sepsis (OR = 6.0; 95% CI, 2.1-17.2; p = 0.001), failure to wean off the ventilator (OR = 3.2; 95% CI, 1.2-8.9; p = 0.022), and postoperative length of stay ≤7 days (OR = 3.0; 95% CI, 1.5-5.9; p = 0.002). Thirty-day mortalities were similar (4.5% vs 7.1%; p = 0.46). Conclusions We propose a novel iAE severity classification system with high internal consistency and solid construct validity. Our classification scheme might prove essential for benchmarking quality of intraoperative care across hospitals and/or individual surgeons.

Original languageEnglish (US)
Pages (from-to)1120-1128
Number of pages9
JournalJournal of the American College of Surgeons
Issue number6
StatePublished - Jun 2014
Externally publishedYes

ASJC Scopus subject areas

  • Surgery


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