Oxygen Concentrator: buying guide for layman (for COVID)

Recently, there has also been a surge in people looking for oxygen concentrators, especially for COVID patients who require oxygen therapy. But what are oxygen concentrators? These devices filter the air in a room and separate oxygen out of it while letting the nitrogen exhaust out. This provides patients with air that has 90% to 96% oxygen, as against the actual ambient air which contains only about 21% oxygen, while 79% air is made of nitrogen and the remaining 1% is other gases.

Buying or renting oxygen concentrators depends on the advice of the physician, as they tell the patients the amount of oxygen required per minute, and thus, the model is selected. Oxygen concentrators have the capability of providing 0.1 liters of oxygen per minute to even 10 LPM of oxygen.

What is difference between 1litre, 5litre and 10litre oxygen concentrators?

1litre machine with adjustable 1-7 LPM flow:

This machine is suitable for home cure for COVID patients whose SpO2 level is not less than 83-85%. In most cases when oxygen therapy is given with this machine the SpO2 level gets maintained above 95%. If the SpO2 level breaches the levels of 83-85% then the patient needs professional nursing with IV facility and the patient must be immediately admitted to a hospital with oxygen bed.

The 1litre machine must be kept at 1-2LPM for COVID patients. Purity of oxygen in 1litre machine at various LPM is as follows:

1LPM: 90%~93%

1.5LPM: 80~85%

2LPM: 65%

3LPM: 55%

4LPM: 50%

6LPM: 35%

7LPM: 30%

This machine is essentially for home cure or for immediate nursing for those patients who are in waiting for a oxygen bed in a hospital. However these machines are also been used in COVID centers and hospitals to give therapy to those patients who need lesser oxygen flow. Excessive use of high flow rate may make a patient dependent on it, hence is not advisable.

5litre machine with adjustable 1-5 LPM flow for more:

5litre machine gives similar concentration of 93-96% oxygen level throughout the flow rate of 1-5LPM. Normally a patient till 70-75% SpO2 level and without other co-morbidity complications do not need more than 5 LPM oxygen flow rate at 93-96% concentration. This machine is suitable for COVID centers, hospitals and health care centers which are under supervision of doctors and nursing staff. The machine could also be bought for home cure, however, patients who need this oxygen flow rate to maintain SpO2 levels also need continuous professional nursing. It is not advisable to treat such COVID patients at home.

10litre machine with adjustable 1-10 LPM flow for more:

10litre machine gives similar concentration of 93-96% oxygen level throughout the flow rate of 1-10LPM. The outlet of oxygen can be split into two and can give oxygen therapy to two patients in one time. Normally a patient till 70-75% SpO2 level and without other co-morbidity complications do not need more than 5 LPM oxygen flow rate at 93-96% concentration. This machine is suitable for COVID centers, hospitals and health care centers which are under supervision of doctors and nursing staff.

The above machines are not suitable to oxygen supply to Intensive Care Units.