TEG-ROTEM guided transfusion may lower death and bleeding in cardiac surgery

Background Severe bleeding and coagulopathy are serious clinical conditions that are associated with high mortality. Thromboelastography (TEG) and thromboelastometry (ROTEM) are increasingly used to guide transfusion strategy, but their roles remain disputed. This is an update of a review that was first published in 2011 and updated in January 2016. Objectives The objective was to evaluate the benefits and harms of TEG‐/ROTEM‐guided transfusion strategies for bleeding in adults and children by comparing TEG‐ROTEM‐guided transfusion with standard treatment. Search methods In this updated review, we identified randomised controlled trials (RCTs) from the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE(R) ALL; Embase; Web of Science Core Collection and Biosis Previews via Clarivate; CINAHL EBSCO; and the WHO Global Index Medicus incl. LILACS (from 2015 up to 5 January 2025). We searched for ongoing clinical trials and unpublished studies in the following registries during the aforementioned period: ISRCTN, ClinicalTrials.gov, CentreWatch, and UMIN‐CTR. We contacted trial authors, authors of previous reviews, and manufacturers in the field. The original searches were run in October 2010 and January 2016. Selection criteria We included all RCTs, irrespective of blinding or language, that compared transfusion guided by TEG or ROTEM to transfusion guided by clinical judgement, guided by standard laboratory tests, or a combination. We also included interventional algorithms including both TEG and ROTEM in combination with standard laboratory tests or other devices. The primary analysis included trials on TEG or ROTEM versus any comparator. Data collection and analysis Two review authors independently abstracted data; we resolved any disagreements by discussion. We presented pooled estimates of the intervention effects on dichotomous outcomes as risk ratios (RRs) with 95% confidence intervals (CIs). Due to skewed data, meta‐analysis was not provided for continuous outcome data. Our primary outcome measure was all‐cause mortality. We performed subgroup and sensitivity analyses to assess the effect of a TEG‐ or ROTEM‐guided algorithm in adults and children on various clinical and physiological outcomes. We evaluated potential bias by examining trial methodological components using the Cochrane Risk of Bias 1 and assessed the risk of random error through Trial Sequential Analysis (TSA). Main results This systematic review included 35 randomised trials (n = 3096), with most involving patients undergoing elective cardiac surgery. Hence, 18 trials and 1603 participants were added since the previous update of this review. TEG‐/ROTEM‐guided transfusion algorithms may be associated with a reduction in mortality (RR 0.76, 95% CI 0.63 to 0.92; 19 trials; 1865 participants, I2= 0%; random‐effects model; very low‐certainty evidence), but the evidence is very uncertain. This aligns with results from a previous update of this review. Additionally, TEG‐/ROTEM‐guided transfusion algorithms may reduce bleeding volume (standardised mean difference ‐0.31, 95% CI ‐0.51 to ‐0.11; 19 trials; 1523 participants, I² = 72%, random‐effects model; very low‐certainty evidence), but the evidence is very uncertain. No effects on the need for packed red blood cells were seen; RR 0.94 (95% CI 0.87 to 1.01; 21 trials, 2003 participants; I2 = 91%; random‐effects model; very low‐certainty evidence), but the evidence is very uncertain. Furthermore, reductions may be observed in the use of fresh frozen plasma (RR 0.52, 95% CI 0.35 to 0.76; 18 trials; 1536 participants; I2 = 94%, random‐effects model; very low‐certainty evidence), platelet transfusions (RR 0.69, 95% CI: 0.55 to 0.87; 20 trials; 1607 participants; I2 = 60%; random‐effects model; very low‐certainty evidence), and in the risk of surgical re‐intervention (RR 0.63, 95% CI 0.45 to 0.88; 13 trials; 1204 participants; I² = 0%; fixed‐effect model; very low‐certainty evidence), but the evidence is very uncertain. Using the GRADE framework, the certainty of the evidence was judged to be very low across all outcomes. TSA for mortality indicated that 64% of the required information size had been reached, with the monitoring boundary for benefit crossed. Authors' conclusions TEG‐/ROTEM‐guided transfusion algorithms may reduce the risk of mortality, bleeding volume, and the need for fresh frozen plasma, platelets, and surgical re‐intervention, but the evidence is very uncertain. Furthermore, the results were primarily based on the adult population undergoing elective cardiac surgery. Hence, the conclusion remains unchanged from the previous update of this review. There is a need for large, low risk of bias randomised controlled trials evaluating TEG/ROTEM across diverse clinical settings, including paediatric and neonatal populations, sepsis, trauma, obstetrics, and high‐risk surgical and critically ill cohorts requiring major transfusion. Future studies should be adequately powered and prioritise patient‐centred outcomes such as long‐term survival, adverse events, cost‐effectiveness, and the role of TEG/ROTEM in coagulopathy and severe haemorrhage. PICOs PICOs Population Intervention Comparison Outcome