Thromboelastography or rotational thromboelastometry for bleeding management in adults undergoing cardiac surgery: a systematic review with meta-analysis and trial sequential analysis

Abstract

Background: Severe bleeding and massive transfusion of blood products may be associated with increased morbidity and mortality of cardiac surgery. A transfusion algorithm incorporating thromboelastography (TEG) or rotational thromboelastometry (ROTEM) can help to determine the appropriate time and target for the use of hemostatic blood products, which may thus reduce the quantity of blood loss as well as blood products transfused.

Methods: We conducted meta-analysis and trial sequential analysis to evaluate the effects of TEG or ROTEM-guided transfusion algorithms vs. standard treatments for patients undergoing cardiac surgery with cardiac pulmonary bypass.

Results: Nineteen studies with a total of 15,320 participants, including 13 randomized controlled trials (RCTs), were included. All-cause mortality was not reduced either in overall studies or in RCTs. Blood loss volume was reduced by 132 mL in overall studies [mean difference (MD): -132.46, 95% CI: -207.49, -57.43; I² =53%, P<0.01], and by 103 mL in RCTs (MD: -103.50, 95% CI: -156.52, -50.48; I² =0%, P<0.01). The relative risks (RRs) in RCTs were 0.89 (95% CI: 0.80-0.98; I² =0%, P=0.02) for red blood cells transfusion, 0.59 (95% CI: 0.42-0.82; I² =55%, P<0.01) for fresh frozen plasma transfusion, and 0.81 (95% CI: 0.74-0.90; I² =0%, P<0.01) for platelet transfusion, respectively. Trial sequential analysis of continuous data on blood loss and dichotomous outcomes on transfusion of blood products suggested the benefits of a TEG/ROTEM-guided algorithm.

Conclusions: TEG or ROTEM-guided transfusion strategies may reduce blood loss volume and the transfusion rates in adult patients undergoing cardiac surgery.

Keywords: Thromboelastography (TEG); adult; blood transfusion; cardiac surgical procedures.

Figure 1

Flow diagram of included and excluded studies.

Figure 2

Risk of bias summary: review authors’ judgements about each risk of bias item for each included study. A green symbol denotes a low risk of bias, while a red one denotes a high risk of bias. A yellow symbol denotes unclear risk of bias.

Figure 3

Forest plot of blood loss in overall studies (A) and in RCTs (B). RCT, randomized controlled trial; TEG, thromboelastography; ROTEM, rotational thromboelastometry.

Figure 4

Trial sequential analysis of blood loss. Trial sequential analysis of 11 RCTs on the effect of transfusion algorithm guided by TEG/ROTEM on blood loss resulted in a statistically significant TSA α-boundary adjusted MD of −102.29 [95% CI: −158.79 to −45.79, diversity (D2) =12%, I² =5%, fixed effect model]. Cumulative Z-curve crossed the monitoring boundary constructed for a required information size of 872 participants corresponding to low bias based mean difference and variance, with 80% power and α of 0.05. However, only one trial had low risk of bias. RCT, randomized controlled trial; TEG, thromboelastography; ROTEM, rotational thromboelastometry; TSA, trial sequential analysis; MD, mean difference.

Figure S1

Forest plot of length of hospital stay. The length of hospital stay (days) reached no statistical significant difference, either in overall study (A) or in RCTs (B). RCT, randomized controlled trial; TEG, thromboelastography; ROTEM, rotational thromboelastometry.

Figure S2

Forest plot of length of ICU stay. The length of hospital stay (hours) reached no statistical significant difference, either in overall study (A) or in RCTs (B). ICU, intensive care unit; RCT, randomized controlled trial; TEG, thromboelastography; ROTEM, rotational thromboelastometry.