Plasma fibrinogen concentration is correlated with postoperative blood loss in children undergoing cardiac surgery. A retrospective review.

Background: Fibrinogen supplementation is increasingly recommended with the use of rotational thromboelastometry (ROTEM). However, data regarding the paediatric population are sparse.

Objective: We aimed to assess the relationship between plasma fibrinogen concentration and postoperative blood loss in children undergoing cardiac surgery.

Design: Retrospective analysis.

Setting: Data prospectively recorded in our departmental database between September 2010 and January 2012.

Patients: Data from 156 children scheduled for congenital heart surgery with ROTEM performed at the end of cardiopulmonary bypass (CPB) were analysed.

Intervention: None.

Main Outcome Measures: Abnormal bleeding was defined as blood loss that exceeded 10% of total blood volume within the first 6 postoperative hours. Logistic regression analyses were used to determine variables associated with bleeding. Correlation analyses and receiver operating characteristic (ROC) curves were designed to evaluate the relationship between blood loss and plasma fibrinogen concentration or ROTEM variables, if relevant.

Results: Thirty-six children were considered as 'bleeders' and 120 as 'nonbleeders'. Univariate and multivariate logistic regression analysis revealed time for wound closure, clot formation time, maximal clot firmness (MCF) and plasma fibrinogen concentration as variables independently associated with postoperative bleeding. MCF was best correlated with plasma fibrinogen concentration. ROC curves for blood loss versus fibrinogen concentration and MCF showed that a plasma fibrinogen concentration of 1.5 g l and a MCF value 3 mm or less could be used to predict blood loss.

Conclusion: Post-CPB plasma fibrinogen concentration significantly influences blood loss in children undergoing cardiac surgery. A fibrinogen concentration of at least 1.5 g l or a MCF of at least 3 mm should accurately predict excessive blood loss in cardiac surgery children. Further prospective trials are needed to assess the effect of fibrinogen supplementation on postoperative blood loss in this population.