Perioperative cardiovascular mortality in noncardiac surgery: Validation of the Lee cardiac risk index

Boersma, Eric; Kertai, Miklos D.; Schouten, Olaf; Bax, Jeroen J.; Noordzij, Peter; Steyerberg, Ewout W.; Schinkel, Arend F.L.; van Santen, Marian; Simoons, Maarten L.; Thomson, Ian R.; Klein, Jan; van Urk, Hero; Poldermans, Don

doi:10.1016/j.amjmed.2005.01.064

« Previous Next »The American Journal of Medicine
Volume 118, Issue 10 , Pages 1134-1141, October 2005

Perioperative cardiovascular mortality in noncardiac surgery: Validation of the Lee cardiac risk index

Eric Boersma
- Department of Cardiology, Erasmus Medical Center, Rotterdam
- Requests for reprints should be addressed to Eric Boersma, Clinical Epidemiology Unit, Department of Cardiology, Room H543, Erasmus MC, Dr Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
Miklos D. Kertai, MD
- Department of Anesthesiology, Erasmus Medical Center, Rotterdam
Olaf Schouten, MD
- Department of Vascular Surgery, Erasmus Medical Center, Rotterdam
Jeroen J. Bax, MD
- Department of Cardiology, University Hospital Leiden, Leiden, The Netherlands;
Peter Noordzij, MD
- Department of Anesthesiology, Erasmus Medical Center, Rotterdam
Ewout W. Steyerberg
- Department of Clinical Decision Sciences, Erasmus Medical Center, Rotterdam
Arend F.L. Schinkel, MD
- Department of Cardiology, Erasmus Medical Center, Rotterdam
Marian van Santen
- Department of Medical Registration, Erasmus Medical Center, Rotterdam
Maarten L. Simoons, MD
- Department of Cardiology, Erasmus Medical Center, Rotterdam
Ian R. Thomson, MD
- Department of Anesthesiology, University of Manitoba, Winnipeg, Canada
Jan Klein, MD
- Department of Anesthesiology, Erasmus Medical Center, Rotterdam
Hero van Urk, MD
- Department of Vascular Surgery, Erasmus Medical Center, Rotterdam
Don Poldermans, MD
- Department of Vascular Surgery, Erasmus Medical Center, Rotterdam

Abstract

Purpose

The Lee risk index was developed to predict major cardiac complications in noncardiac surgery. We retrospectively evaluated its ability to predict cardiovascular death in the large cohort of patients who recently underwent noncardiac surgery in our institution.

Methods

The administrative database of the Erasmus MC, Rotterdam, The Netherlands, contains information on 108 593 noncardiac surgical procedures performed from 1991 to 2000. The Lee index assigns 1 point to each of the following characteristics: high-risk surgery, ischemic heart disease, heart failure, cerebrovascular disease, renal insufficiency, and diabetes mellitus. We retrospectively used available information in our database to adapt the Lee index calculated the adapted index for each procedure, and analyzed its relation to cardiovascular death.

Results

A total of 1877 patients (1.7%) died perioperatively, including 543 (0.5%) classified as cardiovascular death. The cardiovascular death rates were 0.3% (255/75 352) for Lee Class 1, 0.7% (196/28 892) for Class 2, 1.7% (57/3380) for Class 3, and 3.6% (35/969) for Class 4. The corresponding odds ratios were 1 (reference), 2.0, 5.1, and 11.0, with no overlap for the 95% confidence interval of each class. The C statistic for the prediction of cardiovascular mortality using the Lee index was 0.63. If age and more detailed information regarding the type of surgery was retrospectively added, the C statistic in this exploratory analysis improved to 0.85.

Conclusion

The adapted Lee index was predictive of cardiovascular mortality in our administrative database, but its simple classification of surgical procedures as high-risk versus not high-risk seems suboptimal. Nevertheless, if the goal is to compare outcomes across hospitals or regions using administrative data, the use of the adapted Lee index, as augmented by age and more detailed classification of type of surgery, is a promising option worthy of prospective testing.

Keywords: Surgery , Risk , Prediction , Database , Cardiovascular