The impact of spinal anaesthesia for caesarean delivery on coagulation assessed by thromboelastography

Systematic review of viscoelastic testing (TEG/ROTEM) in obstetrics and recommendations from the women's SSC of the ISTH

Thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are point-of-care viscoelastic devices that use whole blood samples to assess coagulation and fibrinolysis. These devices have been studied extensively in cardiac surgery, but there is limited robust evidence supporting its use in obstetrics. The hesitancy toward its routine use in obstetrics may be due to the current lack of randomized controlled trials and large observational studies. The study aims to systematically review studies that investigated TEG/ROTEM use in pregnancy or peripartum, and to provide recommendations for future studies to fill current research gaps. We performed a systematic review of studies on viscoelastic testing in obstetrics. Included studies were original research, used TEG or ROTEM during pregnancy or peripartum, and published in English. Ninety-three studies, spanning 31 years from 1989 to 2020 and with a total of 32,817 participants, were included. Sixty-two (66.7%) of the studies used TEG and 31 (33.3%) used ROTEM. To date, there are a total of two randomized controlled trials on TEG/ROTEM use in obstetrics. ROTEM may be used to guide transfusion therapy for postpartum hemorrhage. TEG and ROTEM can detect the hypercoagulable changes associated with pregnancy. Variability between study protocols and results suggests the need for future large prospective high-quality studies with standardized protocols to investigate the utility of TEG/ROTEM in assessing risk for thrombosis and hemorrhage as well as in guiding prophylaxis and treatment in obstetric patients. This review identifies the gaps and provides concrete recommendations for future studies to fill those gaps.

Cesarean delivery under spinal anesthesia is associated with decreases in cerebral oxygen saturation as assessed by NIRS: an observational study

OBJECTIVES

To investigate the effect of spinal anesthesia on cerebral rSO2 during elective cesarean delivery (CD).

METHODS

Thirty-four women scheduled for elective CD under spinal anesthesia were recruited. In the operating room rSO2 of the left and right frontal area and right thigh was recorded using three disposable sensors. A combination of 1.8-2.0 ml of 0.75% ropivacaine plus 10 μg of fentanyl were injected intrathecally. Systolic and diastolic blood pressure, heart rate, SpO2 as well as rSO2 of the left and right forehead areas and right thigh were recorded before, 5, 10, and 25 to 50 minutes after spinal injection, after uterine incision and placenta delivery, and analyzed with ANOVA repeated measures. The study was approved by the Aretaieio Hospital Institutional Review Board and registered with ClinicalTrials.gov (ID: NCT01669135).

RESULTS

The rSO2 left and right frontal area values decreased significantly from baseline (p=0.0001 and p=0.0001 respectively), with most remarkable decreases 5 and 10 minutes after spinal injection, from 65 (SD 8.7)% to 56 (SD 9.3)% and 56 (SD 9.5)% (p=0.0001 and p=0.0001) for the left and from 63 (SD 7.7)% to 55 (SD 9.3)% and 56 (SD 8.9)% (p=0,0001 and p=0.0001) for the right frontal area respectively. The rSO2 right thigh values increased significantly during the study period (p=0.0001).

KEY LIMITATIONS

Contribution of extracranial circulation to the rSO2, lack of PaCO2 and cardiac output measurements.

CONCLUSIONS

Women undergoing CD under spinal anesthesia may present decreases in cerebral rSO2. The clinical impact of these results remains to be determined.