Prolonged targeted temperature management compromises thrombin generation: A randomised clinical trial.

AIM

To investigate whether prolonged compared with standard duration of targeted temperature management (TTM) compromises coagulation.

METHODS

Comatose survivors after out-of-hospital cardiac arrest (n=82) were randomised to standard (24h) or prolonged (48h) duration of TTM at 33±1°C. Blood samples were drawn 22, 46 and 70h after attaining the target temperature. Samples were analysed for rotational thromboelastometry (ROTEM (EXTEM, INTEM, FIBTEM and HEPTEM)) and thrombin generation using the Calibrated Automated Thrombogram assay.

RESULTS

With the 22-h sample, we revealed no difference between groups in the ROTEM and thrombin generation results beside a slightly higher EXTEM and INTEM maximum velocity in the prolonged group (p-values≤0.04). With the 46-h sample, ROTEM showed no differences when using EXTEM; however, 11% (p<0.01) longer clotting time and 12% (p<0.01) longer time to maximum velocity were evident in the prolonged group than in the standard group when using INTEM. The prolonged group had reduced thrombin generation compared with the standard group as indicated by 30% longer lag time (p=0.04), 106nM decreased peak concentration (p<0.001), 36% longer time to peak (p=0.01) and 411 nM*minute decreased endogenous thrombin potential (p<0.001). With the 70-h sample, no differences in ROTEM results were found between groups. However, the prolonged group had reduced thrombin generation indicated by longer lag time, decreased peak concentration and longer time to peak (all p-values≤0.02) compared with the standard group.

CONCLUSION

Prolonged TTM in post-cardiac arrest patients impairs thrombin generation. ClinicalTrials.gov identifier: NCT02258360.