Can you provide guidance on troubleshooting surgical tables?

Some hospitals charge the healthcare technology management (HTM) department with repairing surgical tables, while others make it the responsibility of the maintenance department. Regardless of the responsible department, HTM staff (biomedical equipment technicians or clinical engineers) will be the first to see the table.

This article describes potential problems that BMETs and clinical engineers may encounter related to surgical tables, as well as tips for troubleshooting these problems.

The table will not move into any position; it just beeps:

If this is a surgical table that articulates into several positions (e.g., Trendelenburg, reverse Trendelenburg, beach chair), then most likely one of the “safety” microswitches has been tripped. There are microswitches on the frame of the table that will not allow the table to be moved into any position until that switch is no longer tripped. This can happen if the foot of the table is all or most of the way down, then someone tries to lower it. If the table is lowered too far with the foot down, the foot would crash into the floor, causing damage to the foot. Therefore, the fix is to raise the leg up until the microswitch is no longer tripped, then lower the table.

The table will not raise and fluid is leaking on the floor:

This issue usually takes the table out of commission for a while. Typically, this is caused by a leak in a hydraulic line or if the hydraulic pump has gone out. Some tables have one main pump (solenoid) and several other pumps (solenoids) for the various functions. In this instance, you might find that some positions work while others do not. This is one of the easier fixes because it is most likely a solenoid repair rather than a pump repair.

A pump repair usually requires all the fluid to be drained and the pump replaced, followed by all of the fluid being returned to the unit and the air bled for the unit. A note of caution: You should never attempt a repair of this type without training. This table can crush and maim you if certain safety precautions are not taken. For this type of repair, the table must be supported. This can be done in several ways, but if you have not been trained by the manufacturer to perform this repair, do not attempt it. It is much easier to call in a qualified repair technician from the manufacturer than to be injured because you were not adequately trained or did not take a safety precaution.

The hand control worked for the last case but is no longer working:

First, do not get hung up on the first part of this statement. Most of our job as BMETs and clinical engineers involves repairing things that worked a minute ago but do not work now.

Focus on the hand control not functioning and use your keen troubleshooting skills. Very often, I find the cable that connects the hand control to the table is either pinched, severed, or unplugged. It is common for the table to pinch this cable when it is moved into or out of various positions. Try to keep at least one spare for every type of table in your surgical department. However, do not panic—the tables are made with back-up controls. They are not full functionality like the hand control, but at the very least, they will raise, lower and lock, and unlock the table.

It is possible that the cable is not severed or unplugged. In this case, try reseating the cable where it connects to the table. Surgical settings have a lot of fluid in them. Sometimes this fluid penetrates, even in the smallest way, the connection. It then dries, causing the connection to be lost. Reseating it will usually break up this corrosion and allow the connection to be reestablished.

Another possibility is an issue with the main control board. I would recommend eliminating all other possibilities initially. Control boards usually are costly, and it would be a shame to spend so much money for an easy, cheap fix.

The table will not lock/unlock:

In this case, first identify whether the table will not lock or unlock. If the table will not lock, check to make sure the pads are still in place on the feet of the table. If one or more are missing, it is possible that the table cannot lock. Another problem could be that one of the microswitches, which activate when the foot is engaged, is not making contact. This may require a simple adjustment or a new microswitch.

If the table will not unlock, this could be a lack of hydraulic fluid to the solenoid or a hand control issue. Try to unlock the table from the controls on the table. If it will unlock from the table controls, then typically this indicates a faulty hand control. If it still will not unlock from the table controls, then most likely the issue is a solenoid, hydraulic fluid, or main board issue.

You can eliminate these one by one. Start by ensuring that there’s an appropriate amount of fluid in the hydraulic fluid reservoir. If this checks out, then move on to the solenoid. Listen or check to see if the solenoid is activating when the appropriate switch is activated. If it is not activating, replace the solenoid.

Once again you should not be replacing these hydraulic-type components without appropriate training. An important note of caution: do not attempt this repair without being professionally trained on the use of hydraulics and the specific table on which you are working.