We have intermittent problems with our battery-operated surgical tables. How can we improve their performance?

I typically see two issues. One is the unit will not work, even when plugged in. We have a couple of different models and vendors in our surgical suites. There are some models that once the battery gets old enough and will not recharge, the whole circuit shuts down. Staff will then bring in another bed and it will work even when plugged in. The bottom line is to have a good battery replacement program. Change those batteries regularly.

Another problem I see quite often, and one that drives the technicians nuts, is an intermittent hand control. One thing that could help is that most tables have a control on the base that allows access to “important” functions: up, down, lock, unlock. Many staff members do not know this function is there. The hand control can keep a technician guessing for some time. I am fortunate enough to have a spare hand control. If able, your facility should purchase a spare. This can be a real life saver.

Regardless, finding the problem is the reason we are biomedical technicians. This can be a challenge at times. Start with the connection from the control to the bed, look for cuts or tears in the wiring harness; these hand controls are flexed and stretched to their maximum throughout their lifetime. Next, if you have another hand control, put that in to determine whether the problem is the hand control. If it is not the hand control, open the base and check the wiring under the connector of the bed. If it is the hand control, carefully open it up and check the wiring. If you've never done this, you will be surprised at how many tiny wires there are under that cover. Although protected, these wires are frail and can get broken. Sometimes the switches are bad, but more often than not a wire has broken off either in the connector or inside the hand control.

A high number of hyper/hypothermia units are reported to be malfunctioning at our facility. What troubleshooting processes and equipment management strategies can be employed to reduce the number of these reported malfunctions?

Are they really broken when you get them? I only ask because I have spent an hour checking the unit out because the clinical staff had said it was broken only to find out the real problem was it would not cool. This might sound like one and the same, but it is not really. If I am told the unit is not heating or cooling, there are some questions I'll ask the staff before I even start testing. First, is the water level correct? Next, are the clamps in the off position on the blanket? Both of these issues will keep the unit in “internal recirculation” and the unit will not heat or cool. Some hyper/hypo thermo units are very sensitive; others are not. Some units will shut off when the clamps are closed, and the pump has to go into internal recirculation mode. Others will run for some time on internal recirculation, waiting for the clamps to be opened. These units are fairly simple. They usually have a condenser, compressor, thermostats, filter, sensors, switches, and some internal valves. So there is not too much to replace. Another possible problem: defective disposable blankets. We have received a few on different occasions. This will be fairly obvious because the clamps will be off and the disposable blanket will not allow water to circulate. Most units will alarm almost as soon as that flow is constricted. Another issue that can arise is a clogged filter. This could happen between preventive maintenance checks if the clinical staff is not using the correct water types. Most units recommend distilled water; tap water could destroy a filter in a few months time. Sometimes, just a few minutes with the clinicians explaining how the unit works can help them look for these problems before they call the biomedical technician.

About the Author

Becky Crossley, CBET, is a BMET III in the Biomedical Engineering Department at Susquehanna Health in Williamsport, PA. E-mail: bcrossley@susquehannahealth.org