Factor VIII inhibitor bypass activity and recombinant activated factor VII in cardiac surgery.

OBJECTIVE: Postcardiopulmonary bypass hemorrhage remains a serious complication of cardiac surgery. Given concerns regarding adverse effects of blood product transfusion and limited efficacy of current antifibrinolytics, procoagulant medications, including recombinant factor VIIa (rFVIIa) and factor eight inhibitor bypass activity (FEIBA), increasingly have been used in managing refractory bleeding. While effective, these medications are associated with thromboembolic complications. This study compared the efficacy and risk of adverse events of rFVIIa and FEIBA in cardiac surgical patients with refractory bleeding. DESIGN: This retrospective study evaluated 168 patients who underwent cardiac surgery and received either FEIBA or rFVIIa to manage postbypass hemorrhage. Demographic, clinical, and outcomes data were collected and statistical analysis performed to compare thromboembolic event rates, relative efficacy, and 30-day mortality following administration of these medications. SETTING: Single university hospital. PARTICIPANTS: Patients undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULT: Sixty-one patients received rFVIIa, and 107 received FEIBA. Demographics, surgical procedures, and preoperative anticoagulation were similar between the cohorts; however, the rFVIIa cohort had longer durations of cardiopulmonary bypass (305.1 v 243.8 min, p<0.01). There were no significant differences in the number of thromboembolic events, 30-day mortality, or rates of revision surgery. Neither group demonstrated a clear relationship between dosage and occurrence of thromboembolic events. The rFVIIa cohort received more platelets than the FEIBA cohort (3.13 v 1.67 units, p = 0.01), but transfusion rates of other blood products were similar. CONCLUSIONS: This study suggests that rFVIIa and FEIBA have similar efficacy and adverse event profiles in managing intractable postbypass hemorrhage in cardiac surgical patients. Further prospective studies are required.

P-wave characteristics on routine preoperative electrocardiogram improve prediction of new-onset postoperative atrial fibrillation in cardiac surgery.

OBJECTIVE: To test the hypothesis that including preoperative electrocardiogram (ECG) characteristics with clinical variables significantly improves the new-onset postoperative atrial fibrillation prediction model. DESIGN: Retrospective analysis. SETTING: Single-center university hospital. PARTICIPANTS: Five hundred twenty-six patients, ≥ 18 years of age, who underwent coronary artery bypass grafting, aortic valve replacement, mitral valve replacement/repair, or a combination of valve surgery and coronary artery bypass grafting requiring cardiopulmonary bypass. INTERVENTIONS: Retrospective review of medical records. MEASUREMENTS AND MAIN RESULTS: Baseline characteristics and cardiopulmonary bypass times were collected. Digitally-measured timing and voltages from preoperative electrocardiograms were extracted. Postoperative atrial fibrillation was defined as atrial fibrillation requiring therapeutic intervention. Two hundred eight (39.5%) patients developed postoperative atrial fibrillation. Clinical predictors were age, ejection fraction<55%, history of atrial fibrillation, history of cerebral vascular event, and valvular surgery. Three ECG parameters associated with postoperative atrial fibrillation were observed: Premature atrial contraction, p-wave index, and p-frontal axis. Adding electrocardiogram variables to the prediction model with only clinical predictors significantly improved the area under the receiver operating characteristic curve, from 0.71 to 0.78 (p<0.01). Overall net reclassification improvement was 0.059 (p = 0.09). Among those who developed postoperative atrial fibrillation, the net reclassification improvement was 0.063 (p = 0.03). CONCLUSION: Several p-wave characteristics are independently associated with postoperative atrial fibrillation. Addition of these parameters improves the postoperative atrial fibrillation prediction model.

Trends in acute kidney injury, associated use of dialysis, and mortality after cardiac surgery, 1999 to 2008.

BACKGROUND: The development of acute kidney injury (AKI) after cardiac surgery is associated with significant mortality, morbidity, and cost. The last decade has seen major changes in the complexity of cardiac surgical candidates and in the number and type of cardiac surgical procedures being performed. METHODS: Using data from the Nationwide Inpatient Sample, we determined the annual rates of AKI, AKI requiring dialysis (AKI-D), and inpatient mortality after cardiac surgery in the United States in the years 1999 through 2008. RESULTS: Inpatient mortality with AKI and AKI-D decreased from 27.9% and 45.9%, respectively, in 1999 to 12.8% and 35.3%, respectively, in 2008. Compared with 1999, the odds of AKI and AKI-D in 2008, adjusted for demographic and clinical factors, were 3.30 (95% confidence interval [CI]: 2.89 to 3.77) and 2.23 (95% CI: 1.78 to 2.80), respectively. Corresponding adjusted odds of death associated with AKI and AKI-D were 0.31 (95% CI: 0.26 to 0.36) and 0.47 (95% CI: 0.34 to 0.65.) Taken together, the attributable risks for death after cardiac surgery associated with AKI and AKI-D increased from 30% and 5%, respectively, in 1999 to 47% and 14%, respectively, in 2008. CONCLUSIONS: In sum, despite improvements in individual patient outcomes over the decade 1999 to 2008, the population contribution of AKI and AKI-D to inpatient mortality after surgery increased over the same period.

Case report: a thrombus in the venous reservoir while using bivalirudin in a patient with heparin-induced thrombocytopenia undergoing heart transplantation.

Direct thrombin inhibitors are heparin alternatives for anticoagulation during cardiopulmonary bypass in patients with heparin-induced thrombocytopenia. We report a case of a large thrombus forming in the venous reservoir while using bivalirudin. We suggest that blood stasis associated with the full venous reservoir maintained in this case led to formation of a large thrombus at the top of the venous canister. Furthermore, activated clotting times may not accurately reflect the magnitude of anticoagulation when using direct thrombin inhibitors.