Initial results of a new access device for hemodialysis technical note

A new subcutaneous device (DIALOCKtrade mark) provides vascular access to patients who currently require hemodialysis (HD). The device consists of a port-like valve, implanted subcutaneously below the clavicle, which provides a linear flow passage to two catheters placed in the right atrium via the internal or external jugular vein. The valve is accessed percutaneously with needle-cannulas that functionally convert the device to twin catheters for connecting the patient to the HD lines.

The device was implanted in 10 outpatients under local anesthesia. Patients used the device during dialysis 3 times/week, and data were collected on blood flow, pressures, adverse events and patient and nurse satisfaction.

The device was used for HD almost immediately (median 3 days after implantation) and functioned successfully for more than nine months (mean +/- SD 7.3 +/- 1.5) in all but one patient who died of unrelated causes after one month; there were >800 dialysis sessions total. Blood flows over 300 ml/min were consistently achieved (average 326 +/- 40) with venous and arterial pressures of 200 +/- 44 and -246 +/- 29 mm Hg, respectively. After 66 patient-months, condition of the needle puncture sites remained satisfactory. Five systemic infections occurred in four patients, producing 2.3 bacteremic episodes per 1000 patient-days. All resolved without the need for device removal. There were no infections at the puncture sites. Two patients required fibrin sheath stripping of their catheters, one whose heparin lock was not changed for 23 days (for reasons unrelated to the device). Patient and nurse acceptance was excellent.

The device represents a positive improvement in the area of HD access.