How to troubleshoot a dialysis machine
Hemodialysis machines are used to replace the renal (kidney) function in people who suffer from end stage renal disease. The function of the dialysis machine is to provide the fluids and other mechanisms necessary for the cleaning of the patient's blood and removal of excess fluid.
Operation of these machines must be conducted by trained personnel only. Dialysis machines have multiple alarms that can occur during treatment, and effectively troubleshooting these alarms increases dialysis efficiency. In order to accomplish this, it is necessary to approach the management of alarm troubleshooting in a systematic manner.
Check whether the blood pump has stopped, and note the type of alarm that has occurred. Dialysis machines notify users of alarms via both audible sound and flashing lights on the control panel of the machine. If the alarm is an "air" alarm, follow the dialysis clinic's protocol, and disconnect the patient from the machine until all of the air has been purged from the blood tubing.
Address arterial and venous vascular access alarms, as they will cause the blood pump to stop. For arterial pressure alarms, check for kinks or clotting in the arterial blood tubing between the patient and the blood pump. Adjustments of the patient's vascular access may be necessary in order to reduce the occurrence of these alarms. Reducing the blood pump speed may also be necessary to effectively troubleshoot this problem. For high venous pressure alarms, check for clotting or kinking in the dialyzer (artificial kidney) and in the venous blood tubing between the dialyzer and the patient. A low venous pressure or a positive arterial pressure may indicate that the patient tubing has disconnected from the machine, or that the blood tubing connection is otherwise not secure. Check that connections are secure before resuming treatment.
Address dialysate conductivity alarms. These alarms do not stop the blood pump. Reasons for conductivity alarms include incorrect dialysate formulation entered into the machine, initiation of sodium profiling, and empty acid or bicarbonate jugs.
Address dialysate temperature alarms. The blood pump does not stop upon occurrence of temperature alarms. They are common when the machine is first set up, as it takes time to properly heat the dialysate to the optimal temperature. The dialysate temperature is typically set at about 37 degrees Celsius.
Address blood leak alarms. These alarms alert the user to possible blood in the dialysate return line, and do not stop the blood pump. Reasons for these alarms include a broken fibre in the dialyzer and a dirty blood leak sensor. If the dialyzer has a broken fibre, treatment must stop and the dialyzer must be replaced. A dirty blood leak sensor is remedied by cleaning the mirror next to the blood leak sensor.
- Alarms that cause the blood pump to stop should be managed as quickly as possible, because if the blood is stagnant in the tubing for too long, it will clot. Excessive clotting in the blood tubing may result in needing to change the entire blood tubing set, which is a time-consuming procedure.
- During alarm conditions, the dialysis clock stops and the patient is not receiving treatment. Excessive alarms during treatment can significantly increase the amount of time the patient must be connected to the machine.
- Always follow the dialysis center's policies and procedures for troubleshooting.
- If machine malfunction is suspected, most dialysis centre policies and procedures advocate removing the patient from the machine immediately.
- All of the troubleshooting techniques discussed within this article are intended to be performed by trained medical professionals. Prescription items are written by a nephrologist (kidney doctor); therefore any changed must be done under the strict supervision of trained personnel.