UNDETECTED EXCESSIVE ULTRAFILTRATION DURING MAINTENANCE HEMODIALYSIS

Undetected excessive ultrafiltration (UF) occurred in 2 patients on ma intenance haemodialysis (HD) using a Gambro AK-10 monitor and Ergo 120 A-G blood lines. In spite of alarms present on the monitor, the dialy sis staff was not alerted to the faulty condition. Through investigati on of the HD 'set-up' at the time of the incidents it was found that a partial obstruction (kinking) had occurred in the extracorporeal bloo d circuit where the flexible tubing joined the venous chamber. This cr eated a very high positive pressure within the dialyzer compartment an d excessive UF, which the blood circuit pressure monitoring transducer was unable to detect. To prevent kinking of the blood lines, dialysis staff and patients should be instructed to ensure that blood lines li e in smooth curves.