Thromboprophylaxis and neuroaxial anaesthesia in obstetrics

Abstract

Spinal hematoma (SH) after neuraxial puncture is considered the most serious complication of regional anaesthesia. The risk is further significantly increased by co-administration of thromboprophylaxis with low molecular weight heparins (LMWH). In the 1990s, the risk of SH on the basis of published case reports was estimated as 1 : 1 000 000. These estimates are now closer to 1 : 3 000. Concomitant application of LMWH is responsible for such a dramatic increase of the risk of SH, especially in orthopaedics. Therefore, a number of anaesthesiology societies have adopted a recommendation concerning the time relation between the administration of neuraxial anaesthesia and LMWH applications. Generally, the risks are only approximated for the low incidence of SH, and for pregnant women this risk is estimated between 1 : 200 000 and 1 : 400 000. If there is an increased risk of SH with concomitant LMWH in orthopaedic patients, in the case of obstetric anaesthesia this increased risk is very questionable. So far there has not been a single published case report giving the context of SH and LMWH use in pregnancy, which, in addition to the physiological hypercoagulable state, differs in altered pharmacokinetics and pharmacodynamics of LMWH. The following text attempts to summarize the current information available regarding the relation of thromboprophylaxis and the risk of spinal hematoma in obstetrics.

Keywords:
LMWH – thromboprophylaxis – regional anaesthesia – spinal haematoma – pregnancy