Baseline parameters for rotational thromboelastometry in healthy labouring women: a prospective observational study

Abstract

ObjectiveThe aim of this study was to establish rotational thromboelastometry (ROTEM®) baseline parameters in labouring women at term gestation. The secondary aim was to compare these reference ranges with those from previous studies on labouring women and from the manufacturer.DesignA prospective, observational study.SettingTertiary referral hospital.ParticipantsHealthy women in labour.MethodsEthics approval was granted for an opt‐out recruitment approach. ROTEM® testing was performed in labouring women at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5% and 97.5% centiles for INTEM/EXTEM/FIBTEM parameters including amplitude at 5 minutes (A5), coagulation time (CT) and maximum clot firmness (MCF).Main outcome measuresROTEM® parameters were measured in labouring women before delivery. The following tests were performed: FIBTEM, EXTEM and INTEM.ResultsOne hundred and twenty‐one women met the inclusion criteria, with a mean (± SD) age of 29.6 ± 5.4 years and median (interquartile range) gestation of 39.4 weeks (37.4–40.4 weeks). Seventy‐five (62.0%) women were nulliparous and 71 (58.7%) delivered vaginally. The median and interquartile ranges for selected ROTEM® parameters were: FIBTEM A5, 21 mm (IQR 18–23 mm); EXTEM A5, 55 mm (52–58 mm); and EXTEM CT, 52 seconds (48–56 seconds).ConclusionsThe FIBTEM/EXTEM/INTEM amplitudes were higher than the manufacturer's reference ranges for non‐obstetric patients. The FIBTEM MCF upper and lower limits were higher and the EXTEM/INTEM CT was shorter and narrower in range. This study provides reference ranges for ROTEM® values in healthy labouring women at term gestation with uncomplicated pregnancies.Tweetable abstractThis is the first study to report on ROTEM® reference ranges with over 120 healthy labouring women of normal weight at term gestation.

How Can Rotational Thromboelastometry as a Point-of-Care Method Be Useful for the Management of Secondary Thromboprophylaxis in High-Risk Pregnant Patients?

“…After the calculation of the median values in our study and their comparison with reference values for particular parameters obtained in non-pregnant population, we can state that all our results stayed in the reference range. On the contrary to the conclusions of the study of Lee et al [ 46 , 47 ], who confirmed higher amplitudes in studied individuals when compared with the non-pregnant population, in our study, the results stayed normal probably due to the use of the anticoagulant thromboprophylaxis. However, the reference ranges were determined in the non-pregnant population, so they could be evaluated in a different way using the ranges for the (high-risk) pregnant population.…”

“…On the other hand, ROTEM may detect the hypercoagulable state associated with pregnancy [ 8 ]. Lee et al performed a prospective observational study of baseline parameters for ROTEM in healthy laboring women with uncomplicated pregnancy concluding that FIBTEM, EXTEM, and INTEM amplitudes were higher at term gestation than the determined reference ranges for the non-obstetric population [ 46 ]. The same authors evaluated baseline parameters of ROTEM in healthy pregnant women undergoing elective caesarean section.…”

Viscoelastic Testing in an Obstetric Population at High Risk of Hemorrhage

“…externally valid in a more diverse US population 6,[13][14][15][16][17][18][19] . Establishment of valid reference ranges is the first step in implementing a goal-directed transfusion protocol.…”

Viscoelastic Hemostatic Assays for Postpartum Hemorrhage

“…This delay may in part be due to the significant complexity of the definition of PPH. Additionally, the adoption of VHAs in the PPH treatment may also be contributed to the lack of established transfusion trigger values, which have only been published recently [48][49][50]. A review of the timeline for the adoption of VHAs in trauma revealed a significant lag of approximately a decade which has been reproduced for PPH [3,12,25,[51][52][53][54][55][56][57][58][59][60].…”

“…Studies have established a correlation between low fibrinogen levels and the incidence of PPH, but the low sensitivity and long turnaround time of this CCT make it insufficient for guiding BCT/HAT in PPH patients [71,72]. There is evidence in the utility of ROTEM in PPH as demonstrated by correlation between FIBTEM A5 and classical Clauss fibrinogen levels [48,73].…”