Abstract P189: Use of rFVIIa for Critical Bleeding in Cardiac Surgery: Dose Variation Does Not Predict Patient Outcomes
Background: Recombinant activated Factor VIIa (rFVIIa) is increasingly being used in non-haemophiliac patients (i.e. off-licence) for the treatment of severe bleeding refractory to standard interventions. Optimal dosing regimens remain debated across a variety of clinical contexts, including cardiac surgery. Therefore, this study investigated the use of different rFVIIa dosing practices on response to bleeding and patient outcomes in cardiac surgery patients using data from the Haemostasis Registry.
Methods: Data were extracted from the Haemostasis Registry that collects both contemporaneous and retrospective cases of off-licence rFVIIa use in participating institutions (~90 hospitals across Australia and New Zealand). In the Haemostasis Registry, cardiac surgery includes all surgical interventions on the heart or on major thoracic vessels that require cardiopulmonary bypass. Univariate analyses compared patients receiving low (less than 81μg/kg) medium (81 to 100μg/kg) and high (greater than 100μg/kg) doses of rFVIIa on key parameters. Logistic regression was used to investigate the relationship between independent variables and response to bleeding and 28 day mortality.
Results: Complete data was available on 804 patients undergoing cardiac surgery who received rFVIIa. Of these, 253 (31.47%) were treated with ‘low’ dose therapy, 368 (45.77%) with medium doses and 183 (22.76%) with ‘high’ dose therapy. Patients in each dose category did not demonstrate clinically meaningful differences on measures of acuity, transfusion requirements or prior medications. Results demonstrated no significant differences in the rate of thromboembolic adverse events, response to bleeding or 28 day mortality (Table 1⇓).
Conclusions: These findings raise the important question of whether lower doses of rFVIIa may be as effective and efficacious as higher doses in the treatment of severe bleeding in cardiac surgery patients.