Back close


May 2, 2021 - 6:11

COVID care center Amrita Hospital Kochi
0484 668 1000

Post-COVID care center Amrita Hospital Kochi

Here are a few facts you should know for COVID-19 emergencies


  • Oxygen concentrators are to be used if oxygen concentration levels are below 94% (spO2)**, that is, for mild and moderate patients only.
  • Do not attempt to treat yourself with oxygen without medical supervision. Concentrators are not a substitute for medical attention. They are useful when the doctor advises you to use them or you have mild/moderate infection and may not need hospital admission. You will still need to have remote medical supervision even when you are at home.
  • Keep all the windows and doors open while using the oxygen concentrator. An oxygen concentrator doesn’t have reserve oxygen, it extracts air from the room and discharges oxygen. So, air in the room needs to be renewed, even more than during normal usage.
  • Continuous monitoring of SpO2 levels, that is oxygen concentration levels, of COVID patients is important in successful management via Oxygen Concentrator. Seek medical attention if saturations drop or if any concerns arise.
  • Always seek medical advice for any questions you may have and before pursuing any form of medical treatment, including Oxygen Concentrators. The facts and recommendations provided by this article are only information about Oxygen Concentrators, as stated in the Disclaimer below. They apply to adults only. Please follow State regulations and guidelines.

** Reference for this number Kerala State Guideline and IDSA (Infectious Diseases Society of America). Range given in Kerala state Guideline is (90-94).

Ways of oxygen and specific requirements:

1. Oxygen delivered through nasal prongs

2. Oxygen delivered through mask

Image Sourced from WikiHow

Maximum delivery through nasal prongs would be upto 3l/minute, above that would mandate a mask.

Tips on selecting the right oxygen concentrator

The most important point to understand is that COVID patients require 90% Oxygen concentration at 1-5 litres per minute (LPM) flow and above 10 LPM when they are suffering with acute respiratory discomfort.

Supply of 90% oxygen concentration is mandatory. Weight of the machine is the best indicator to understand the oxygen production capacity. (Heavier normally implies greater capacity)

What is in the market:

  1. a) Small (5-10 kg) concentrators, suitable for COPD patients
    Small oxygen concentrators can have options from 1-9 LPM flow but this does not mean you get 90% oxygen at higher flow like at 5 LPM. On small oxygen concentrators 90% oxygen concentration is achieved only at lower flows of 1-2 LPM. As you increase the flow, on higher flows the oxygen concentration drops to 30%. So, these are suitable for COPD patients but not for COVID patients. (COPD patients are those with chronic breathing difficulties needing O2 24 hours irrespective of COVID status)Check the specs of the oxygen concentrator and if you see 90% – 30% or ( 1LPM, 2LPM) means 90% oxygen is available only at 1 or 2 LPM flow respectively and on higher flows oxygen drops to 30%. The air we breathe has 21% oxygen. So a small (5-10kg ) oxygen concentrator means a small compressor, so at higher flows it gives output of 30% oxygen means it’s just blowing air and not 90% oxygen. A 5-10kg oxygen concentrator will usually only manage to give an output of 90% oxygen at 1-2 LPM
  2. b) Medium (15-19kg) concentrators A 15-19kg oxygen concentrator will have a compressor that can easily give an output of 90% oxygen at flows from 1 Litre to 5 Litre Oxygen (Maybe suited for COVID patients with mild to moderate disease)
  3. c) Large (20kg and above) concentrators, suitable for critical and COVID patients A 20 kg and above oxygen concentrator will have a large compressor which can give an output of 90% oxygen from 1-10 LPM flow. (Ideal for COVID patients and critical care patients and for dual patients to use same machine with accessories)
Please do not only see the output flow of an oxygen concentrator like 5, 10 LPM or so. The most important is to make sure you get 90% Oxygen at the highest flow level.

Recommendations for selection of oxygen concentrators for a family

  • For a small family with no senior citizens, a 5 litre at 90% oxygen concentration may be good enough.
  • For 2 senior citizens or for a big family, 10 litre at 90% oxygen concentration may be good enough as it can support 2 patients at once if the need arises. And can assist senior citizens during home critical care if the need arises.

Recommendation of oxygen concentrator for COVID patients:
If the patient is

  • Adult (Mild): May not need Oxygen to maintain saturations above 94% or may need lower flow rate of Oxygen and their requirements may be managed with 5 LPM machine at home
  • Adult (Moderate): Oxygen requirement MAY be managed with a 5-10L/M machine at home WITH MEDICAL SUPERVISION with a goal to keep Oxygen saturation above 94%. If oxygen levels fall below 94%(spO2) in spite of home Oxygen, hospitalization and appropriate medical attention is needed
  • Adult (Severe): Please DO NOT rely on concentrators, you need to get them to a hospital

*The above recommendations are only for adults in general. They do not apply to children, pregnant women or vulnerable adults. Please consult with medical doctors for any advice or recommendation for children, pregnant women and vulnerable adults, including for the use of Oxygen Concentrators.

*Please note that each State has its own regulations and guidelines, which need to be followed.

*This is only for oxygen, medicines and other treatments will need to be taken care of as well.

Monitoring at home

  1. keep a book with time and date (VERY IMPORTANT)
  2. parameters to be monitored: spo2, heart rate, respiratory rate
  3. record 6- 8 hourly
  4. keep a medical practitioner informed about the trend.
  5. despite having acceptable saturation if there’s clinical worsening seek medical attention

References or more information:

How to use oxygen concentrator at Home by Dr. Bornali Dutta is external)

Finger Pulse Oximeter:

Oxygen concentrators should be used along with home pulse oximeter to measure the saturations. During a pulse oximetry reading, a small clamp-like device is placed on a finger. Small beams of light pass through the blood in the finger, measuring the amount of oxygen. It does this by measuring changes of light absorption in oxygenated or deoxygenated blood. This is a painless process. The pulse oximeter will thus be able to tell you your oxygen saturation levels along with your heart rate.

Some concentrators NOT suitable for COVID applications

Please do not get fooled and pay big money for small oxygen concentrators sold by highlighting 5 Litre and 8 Litre and do not give an output of 90% concentration of oxygen at higher flows which is the need of the hour. Please read the specs well and if required please ask your supplier to show you the oxygen output on an oxygen analyzer at higher flow of 5-10 LPM.

Some concentrators suitable for COVID applications

A 15-19kg oxygen concentrator will have a compressor that can easily give an output of 90% oxygen at flows from 1 Litre to 5 Litre Oxygen, ideal for COVID patients and critical care patients. A 20 kg and above oxygen concentrator will have a large compressor which can give an output of 90% oxygen from 1-10 LPM flow, ideal for COVID patients and critical care patients and for dual patients to use same machine with accessories

List of oxygen concentrators for online purchase with output above 8 LPM of airflow…(link is external)

WHO document for technical specifications for oxygen concentrators for reference…(link is external)

WHO document for oxygen sources and distribution for COVID 19 treatment Centres…(link is external)

We wish all the best of health and hopefully none of us has to use an oxygen concentrator.

This information was put together by : Dr. Dipu TS (Infectious Diseases), Dr. Sreelakshmi.P.Leeladharan (Cardiac anaesthesia), Dr. Mahesh Kappanayil (Paediatric Cardiology), Dr. Bendapudi Perraju (Neonatology) from AIMS supported by Ayyappan Ajan, Vishnu Jayan, Tzur Sayag, and Dr. Bhavani Rao R from Ammachi Labs

Links to third party websites do not constitute an endorsement and none should be inferred.


As mentioned at the beginning of this article, please note these are recommendations only, based on the state of scientific knowledge at the date of publication. Information is provided without any representations or warranties, express or implied. The information provided is not to be considered as Medical Advice. The authors, Amrita Vishwa Vidyapeetham and any of its affiliated entities do not take responsibility for any adverse effects from improper use of O2 Concentrators. Always consult a Medical Doctor before pursuing any form of medical treatment,

including O2 Concentrators. This is by no means a substitute for proper medical attention and supervision and if any concerns or questions arise, please contact a medical personnel. Third party links are provided for your references only. They do not constitute an endorsement and none should be inferred.

You agree not to hold us liable for any damages arising from or relating to your reliance on any of the information provided, including the content of third parties’ website. Additionally, you agree not to repeat the information that you received from this website to a third party as that third party may not have read this disclaimer and understood the caveats involved in receiving the information.

Admissions Apply Now