Fibrinogen Concentration Significantly Decreases After On-Pump Versus Off-Pump Coronary Artery Bypass Surgery: A Systematic Point-of-Care ROTEM Analysis

OBJECTIVES: Studies have emphasized the importance of normal fibrinogen concentrations in surgical patients. The primary hypothesis of this study was that fibrinogen levels significantly decrease in on-pump coronary artery bypass graft (CABG) surgery versus off-pump coronary artery bypass graft (OPCAB) surgery. The second objective was to show that ROTEM (TEM International, GmbH, Munich, Germany) rapidly detects these abnormalities compared with standard tests.

DESIGN: A prospective, nonrandomized study.

SETTING: A university hospital.

PARTICIPANTS: Forty-two and 62 patients in the CABG and OPCAB groups, respectively, undergoing first-time bypass surgery were included.

INTERVENTIONS: CABG versus OPCAB surgery.

MEASUREMENTS AND MAIN RESULTS: Routine coagulation tests and ROTEM values were measured before anesthesia (T0), after the first dose of heparin (T1), after protamine (T2), upon intensive care unit arrival (T3), and 4 hours postoperatively (T4). The outcome measures were followed until 4 hours postoperatively. Fibrinogen concentrations were significantly lower in the CABG versus the OPCAB group at T2 (170 ± 44 v 243 ± 73 mg/dL, p < 0.001) and T3 (179 ± 42 v 232 ± 68 mg/dL, p < 0.001). This was confirmed by significantly lower FIBTEM maximal clot firmness values at T2 (9 ± 4 v 14 ± 5 mm, p < 0.001) and T3 (9 ± 4 v 13 ± 6 mm, p < 0.001). In the CABG group, patients received significantly more transfusions of all blood products except fresh frozen plasma.

CONCLUSIONS: Fibrinogen concentration significantly decreases after cardiopulmonary bypass. ROTEM helps in its fast detection.