A programmable and implantable pumping system for systemic chemotherapy: a performance analysis in 52 patients.

Abstract
We have prospectively evaluated the performance of the implanted battery-powered Medtronic (Minneapolis) SynchroMed infusion system. Between July 1984 and July 1986, fifty-three SynchroMed pumps were implanted in 52 patients for phase I and II trials of low-dose continuous-infusion doxorubicin (N = 35) or vinblastine (N = 17). The median duration of pump function was 145 days (mean, 180; range, 20 to 787+) and the systems infused drugs for 61% (range, 32% to 100%) of their patient implant time. During 10,045 patient days (27.5 years) of implantation, there have been no failures of the pump mechanism and pump accuracy was excellent (2.2% error rate in 256 analyzed refills). The median cost of the hospitalization for implantation was $17,140 in 14 analyzed cases. Complications requiring a second surgical procedure occurred with 13 systems (24%). Two of the complications were related to localized cutaneous hypersensitivity to vinblastine, four were directly related to system complications, and seven were secondary to implant procedure problems. Seven patients (13%) requested removal of the device after tumor progression occurred. Based on this experience, the company has made improvements in certain aspects of system design and has implemented a comprehensive user training program to minimize procedure-related problems. The Medtronic SynchroMed is an accurate and sophisticated system that allows infusion of low-dose doxorubicin and of vinblastine for prolonged periods. Extravasation of these vesicant agents must be carefully prevented. The financial cost of this implanted system may limit its use to patients with an expected survival of 5 months or longer.