Cardiovascular disease in pregnancy classified after the WHO risk-index: a retrospective observation of different anaesthetic methods during cesarean sections
Wittmann M., Guttenthaler V., Baumgarten G. University Hospital Bonn, Dept of Anaesthesiology & Intensive Care, Bonn, Germany Background and Objective: Heart diseases increase the risk of maternal and neonatal complications in pregnant women. The treatment of this patient group from preconceptional counseling to postnatal monitoring increasingly attract attention as growing numbers of pregnant women present with heart diseases.
Methods: In this retrospective observatory monocenter study all pregnant women with heart diseases that gave birth at the University Hospital of Bonn within a timespan of ten years and their newborns were included. Maternal outcome parameters were the length of hospital stay (LOS) and an eventual postpartal stay in the intensive care unit (ICU). The APGAR score, the pH-value and the Base-Excess-value of the umbilical cord were evaluated as primary outcome parameters for the newborn. The patients were categorized according to the WHO risk index modified by Thorne (Thorne et al, 2006). The outcome parameters were analyzed in dependency to the patients´ WHO risk class and, if applied, the chosen anaesthetic method during cesarean section.
Results: 65 women with 77 pregnancies were studied. Applying the Kolmogorov-Smirnov-test we found a significant relationship between the LOS and the anaesthetic method during a cesarean section (p = 0.043). The Kruskal-Wallis-test showed that the LOS and the WHO risk class (p = 0.02) were correlated significantly. For the newborns a significant relationship between the WHO risk classes of the mother and the APGAR scores after 5- and 10-minutes (p = 0.041 and p = 0.017 respectively) was observed. There was no significant influence of the chosen method of anaesthesia during a cesarean section on the pH-value of the umbilical cord or the Base Excess (BE)-value of the newborn.
Conclusions: This study could confirm the results of other trials showing that cardiovascular diseases have negative effects on the outcome of mother and newborn. The modified WHO risk index seems to be an adequate tool to classify the patients with cardiac diseases and might be applicable for anaesthesiologic risk assessment. The validity of the outcome values is limited due to the small number of available patients. Due to the retrospective design of the study, a long term follow up could not be carried out. A prospective multi-center study could provide more sustainable evidence to support guideline development on peripartum anaesthetic management of women with cardiovasular disease.

Cardiovascular disease in pregnancy classified after the WHO risk-index: a retrospective observation of different anaesthetic methods during cesarean sections