An International Benchmarking Collaboration: Measuring Outcomes for the Hypertensive Disorders of Pregnancy

Objective: To implement a set of clinical indicators to benchmark outcomes for women suffering from the hypertensive disorders of pregnancy. Methods: Seven clinical indicators were designed and applied retrospectively to data collected from two tertiary referral centres, Royal Prince Alfred Hospital, Sydney, Australia and British Columbia Women's Hospital and Health Centre, Vancouver BC, for all women coded as hypertensive during pregnancy under the International Classification of Disease (ICD-10) coding system in the years 2002-2004. Diagnostic categories were assigned using the Australasian Society for the Study of Hypertension in Pregnancy criteria, expressed in equivalent Canadian terms drawn from the Report of the Canadian Hypertension Society Consensus. Comparisons were made using the established clinical indicators. Data analysis using chi-square comparison was performed with significance set at P < 0.05. Seven outcome measures of maternal and neonatal mortality and morbidity were compared. Results: Significant areas of difference between the two tertiary referral centres were seen in birth weights below the 10th centile (RPA 11% vs. BCW 20%; P < 0.05) and below the 3rd centile (RPA 1.5% vs. BCW 7.5%; P < 0.001). There were significantly more episodes of maternal pulmonary edema at BCW than at RPA (0.1% and 1.2%, respectively; P < 0.001). Conclusion: Between similar centres, clinically significant differences in outcomes for HDP were identified. Further evaluation of differences may lead to analysis of possible contributors such as expectant versus urgent delivery management policies, rigidity of blood pressure control, and choice of antihypertensive drug.