Reducing Downtime in Oxygen Concentrators

Abstract

Q: We have 15 oxygen concentrators throughout our error that must be facility. We constantly get a low O2 addressed. Is there any way to reduce downtime due to this error?A: Oxygen concentrators have several applications within healthcare. Specifically, they are used as an alternative to a bulky, heavily regulated oxygen tank. As their name implies, these stationary units take nitrogen from room air and provide a flow of higher-than-normal oxygen concentration.Normal room air comprises about 79% nitrogen and 21% oxygen. These small machines extract the nitrogen through filters and compression and produce oxygen that is approximately 90% pure (the percentage and liters per minute delivered vary by machine; check the manufacturer's specifications for the devices in your facility). The compressor in the concentrator compresses the room air to roughly 20 pounds per square inch (PSI). The compressed air is then filtered through a canister containing zeolite granules. Zeolite is usually the granule of choice because it absorbs nitrogen. Zeolite crystals have a life expectancy of about 20,000 hours—about 10 years of normal use. After the air is filtered, oxygen molecules are available for use. Then the compressed air is diverted to a second canister of zeolite where the process is repeated. When pressure in the second canister reaches 20 PSI it will cause the pressure in the first canister to be reduced to zero. This decrease of pressure allows for nitrogen to be released from the zeolite and returned to the atmosphere. Because the pressure alternates between the canisters, a constant supply of oxygen is produced. Finally, the oxygen passes through a small reservoir chamber, a flow control system, and then to the patient. Most machines can produce a flow rate up to four liters per minute. Higher flows are possible but they result in loss of oxygen concentration. Thus most machines have flow limiters to prevent this loss from occurring.Oxygen concentrators are fairly easy to maintain if some basic steps are followed. They must be operated in a well ventilated area to ensure that they receive the good “clean” air they need. Wash and replace the filters routinely. And of course practice good safety precautions: never operate in the presence of a fire, including smoking around the concentrator.Now, to the question: First of all, check for leaks, specifically in the tubing and filters. A leak in either one will cause a loss of pressure and a low O2 reading. Second, check the valve timing to make sure the timing is 10–12 seconds per cycle. If the timing is higher than 12 seconds, there is likely a problem with the sieve beds. Replace the sieve. Next check the pressure at the output of the sieve beds. This pressure should be 25–28 PSI. Be aware that pressure is dependent on building elevation. If the pressure is less than 25 PSI there are three things you can check for: 1) a leak in the tubing or in the valve assembly; 2) a blocked filter; or 3) a faulty compressor. If the off cycle does not drop to 1.5 PSI or less, the valve assembly is most likely leaking internally and you need to replace the valve.These are the steps we walk through at our facility. We have also found that a regular preventive maintenance schedule and an annual change of filters have helped to reduce downtime with these units.