///2017 Abstract Details
2017 Abstract Details2019-08-02T15:54:53-05:00

A modified Delphi approach to establish a consensus expert opinion on whether to proceed with neuraxial anesthesia in pregnant women receiving thromboprophylaxis

Abstract Number: SAT-05
Abstract Type: Original Research

Lisa Leffert M.D.1 ; Heloise Dubois B.S.2; Timothy Houle PhD3; Ruth Landau M.D.4


A SOAP Taskforce convened to create a consensus statement in response to the 2016 National Partnership for Maternal Safety Obstetric Thromboprophylaxis Bundle.(1)Given sparse data on the anticoagulant pharmacokinetics in pregnancy and associated spinal epidural hematoma (SEH) risk, experts in the field were asked to provide their opinion through a modified Delphi approach.


A REDCap survey was sent to obstetric anesthesia leaders and hematology experts. Respondents were asked to use ‘clinical intuition to answer’ and to ‘estimate the # of additional obstetric patients who would experience a SEH for each million neuraxial procedures’ at select heparin doses at varying time intervals since last dose. The SEH rate of 3-4:1,000,000 in obstetric cases was the baseline.

Analyses included descriptive statistics appropriate to measurements, including frequency counts (%) and median and IQR (25th, 75th percentile). The central tendency (expected value) and variation (95%CI) in clinical assessments were estimated assuming the distribution of events would follow a negative binomial distribution.


The majority of experts (17/27 [63%]) estimated the SEH risk to be comparable to baseline risk if neuraxial was performed >6h after 5000U SQ UFH (Fig). For 5000U SQ < 6h, the additional risk estimate was also low (median +1 additional SEH:1,000,000; IQR: 0, 2) and 77% of respondents would proceed with neuraxial labor analgesia (NLA). If parturient was morbidly obese with a Category II fetal heart tracing, 85% would proceed with NLA and 96% with neuraxial anesthesia for CS. However, the estimated additional risk increased with 7500U and 10,000U: only 46% would proceed if the woman had received 7500U SQ within 6h, and only 8%, if she received 10,000U SQ within 6h. Most (89%) would not proceed with NLA within 10 hours of an enoxaparin 60mg SQ dose.


This modified Delphi of experts describes perceived risk of SEH with obstetric thromboprophylaxis and identifies minimal additional risk of proceeding with NLA within 6h of 5000U SQ UFH. Increasing concern at higher doses highlights the need for rigorous multidisciplinary planning for the peridelivery management of thromboprophylaxis. These results also demonstrate the experts’ commitment to neuraxial labor analgesia and anesthesia when general anesthesia-associated complications appear to outweigh the perceived risk of SEH.

1.Friedman,Anesth Analg2016;123:806-8.

SOAP 2017