Coagulation in the HIV-positive pregnant patient: a thromboelastography study

Abstract

Background: HIV infection is associated with haematological changes, including thrombocytopaenia. Pregnancy induces a hypercoagulable state. There are limited data on the coagulation status of women with term pregnancy and HIV receiving antiretroviral medication. Regional anaesthesia is the technique of choice for caesarean section (CS), and is contraindicated in a hypocoagulable state. We therefore investigated the coagulation status of term pregnant women with HIV, presenting for elective CS.
Methods: This was a single-centre cross-sectional observational study, using thromboelastography, comparing the coagulation status of HIV-negative and -positive women with no other comorbidities, in pregnancy at term. A blood sample was taken immediately prior to spinal anaesthesia, and thromboelastography was performed within four minutes. In addition, platelet count, haemoglobin, and fibrinogen level were measured.
Results: Blood samples were obtained from 75 patients. There were no between-group differences in obstetric and demographic data, and no difference in platelet count. The mean (standard deviation [SD]) fibrinogen level was higher in HIV-positive women (3.9 [1.5] vs 3.5 [0.7] g/L) respectively, p = 0.04. There were no significant differences in the r time, alpha angle, k time, maximum amplitude (MA), or LY-30.
Conclusions: The results of this thromboelastography study show that in asymptomatic HIV-positive pregnant patients on antiretroviral treatment, there are no significant differences in coagulation parameters when compared with HIV-negative patients. This suggests that routine assessment of coagulation is unnecessary before spinal anaesthesia in patients without further comorbidities. Further studies could demonstrate the incidence of abnormalities in coagulation or platelet function in patients with AIDS-defining disease or HIV-positive patients with other comorbidities.