Neuraxial anesthesia in parturients with thrombocytopenia: A multisite retrospective cohort study

BACKGROUND: The primary aim of this study was to estimate the risk of neuraxial hematoma associated with neuraxial anesthetic procedures in thrombocytopenic parturients. METHODS: A multicenter retrospective cohort study design was used to estimate the risk for spinal-epidural hematoma in parturients with a platelet count of <100,000/mm³ receiving neuraxial anesthesia and the risk of complications in thrombocytopenic parturients who receive general anesthesia. RESULTS: No cases of spinal hematoma were observed in 102 thrombocytopenic parturients receiving epidural analgesia or 71 receiving spinal anesthesia. Including data from the previous published series (total n = 499), the exact binomial 95% confidence interval for the risk of spinal-epidural hematoma was 0% to 0.6%. Given the small number of patients at each specific platelet count, the theoretical risks at individual platelet count strata are presented. Overall aggregate serious morbidity rate in women who received general anesthesia secondary to thrombocytopenia was 6.5% (95% confidence interval, 2.1%-14.5%). CONCLUSIONS: Our work supports the relative maternal safety of neuraxial anesthesia in parturients with mild thrombocytopenia and estimates the maternal complication rate associated with the avoidance of neuraxial anesthesia. Remaining uncertainties at lower platelet counts make a national "low platelet" registry critical to a more accurate assessment of the risk of epidural hematoma and would aid in standardization of anesthesia practice.