Evaluation of standard and modified severity of illness scores in the obstetric patient

Stephen E Lapinsky; David Hallett; Nancy Collop; John Drover; Peter Lavercombe; Marc Leeman; Shiraz Moola; Fathima Paruk; Michael Bernstein; Jack Moodley

doi:10.1016/j.jcrc.2010.10.003

Evaluation of standard and modified severity of illness scores in the obstetric patient

J Crit Care. 2011 Oct;26(5):535.e1-535.e7. doi: 10.1016/j.jcrc.2010.10.003. Epub 2010 Nov 23.

Authors

Affiliations

¹ Intensive Care Unit, Mount Sinai Hospital and the Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada M5G 1X5. Electronic address: stephen.lapinsky@utoronto.ca.
² Intensive Care Unit, Mount Sinai Hospital and the Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada M5G 1X5.
³ Division of Pulmonary/Critical Care Medicine, The Johns Hopkins University, Baltimore, MD 21205, USA.
⁴ Critical Care Program, Queen's University and Kingston General Hospital, Kingston, ON K7L1V9, Canada.
⁵ Intensive Care Unit, St Andrew's War Memorial Hospital, Brisbane 4000, Australia.
⁶ Department of Intensive Care, Erasme University Hospital, Brussels 1070, Belgium.
⁷ Kootenay Lake Hospital, Nelson, BC V1L2V1, Canada.
⁸ Department Of Anaesthesiology, University of Witwatersrand, Johannesburg 2000, South Africa.
⁹ King Edward VIII Hospital and Womens Health and HIV Research group, University of Kwa Zulu Natal, Durban 4013, South Africa.

PMID: 21106337
DOI: 10.1016/j.jcrc.2010.10.003

Abstract

Purpose: To test discrimination and calibration of APACHE-II and SAPS-II risk prediction scores in a cohort of obstetric patients, and to evaluate the effect of modifying these scores for the physiological changes in pregnancy.

Materials and methods: A retrospective review of obstetric patients, 12 weeks gestation to 48 hours postpartum, admitted to the ICU for more than 24 hours. APACHE-II and SAPS-II, and versions modified for the physiological changes of pregnancy, were evaluated by receiver operating characteristic (ROC) curves and standardized mortality ratios (SMR). Multivariable analysis identified other parameters associated with mortality.

Results: Data were obtained from 332 patients from 5 countries, with a mortality rate of 12%. Mean (± SD) APACHE-II score was 16.8 ± 6.1 and SAPS-II score 26.5 ± 15.8. Good discrimination was demonstrated with area under the ROC curves of 0.82 and 0.78 respectively, with no improvement after modification for altered maternal physiology. APACHE-II overestimated mortality, with an SMR of 0.43 (0.52 after including diagnostic weighting) compared with 0.89 for SAPS-II. Bilirubin, albumin and Glasgow Coma Scale were independently associated with mortality.

Conclusion: APACHE-II and SAPS-II are good discriminators of illness severity and may be valuable for comparing obstetric cohorts, but APACHE-II significantly over-estimates mortality.

Publication types

Comparative Study
Evaluation Study
Multicenter Study

MeSH terms

APACHE*
Adult
Analysis of Variance
Calibration
Female
Hospital Mortality*
Humans
Intensive Care Units / statistics & numerical data*
Monitoring, Physiologic
Pregnancy
Pregnancy Complications / mortality*
Pregnancy Complications / physiopathology
ROC Curve
Retrospective Studies
Risk Assessment / methods
Severity of Illness Index*
Young Adult