Use of an innovative syringe pump to deliver bolus rFVIIa for patients with haemophilia and inhibitors undergoing surgery

Aim: To evaluate the efficacy and safety of using a syringe driver perfusor pump to deliver frequent regular bolus doses of rFVIIa peri- and postoperatively to patients with severe haemophilia and inhibitors. Background: The provision of surgical haemostatic coverage with rFVIIa requires regular bolus doses, initially every two hours and subsequently three-hourly, moving to four- to six-hourly post-operatively. This has implications for safety and nursing time, and can influence clinical decision-making. We investigated the use of an infusion pump to deliver timed and accurate rFVIIa bolus doses during the postoperative period. Methods: Two patients with severe haemophilia A and inhibitors undergoing three procedures were managed with a pre-surgical bolus infusion of 120mcg/kg of rFVIIa, followed by postoperative doses of 90mcg/kg every two hours for the first 72 hours, and every three hours subsequently, with increasing dose intervals thereafter. All postoperative bolus doses were delivered via a pre-programmed infusion pump. The pump also required a constant background infusion set at 0.1ml/ hour for the first patient, and reduced to 0.01ml/hour for the second patient. Results: The pump was simple to use and readily accepted by patients and nursing staff. There were no delayed or missed doses, and good haemostasis was maintained. Overall nursing time involved in reconstituting and administering rFVIIa was reduced from three to six hours per treatment day (with conventional bolus dosing) to just one to two hours per day with the pump. Conclusions: The syringe pump successfully delivered the correct doses at the specified time intervals for all three procedures. The technique met the centre’s safety and efficacy criteria and resulted in a significant reduction in the amount of nursing time needed over a 24-hour period. This novel method of rFVIIa administration appears to be safe and effective in the elective surgery setting, and should be further investigated.