On April 28, the Government of India announced it will procure one lakh oxygen concentrators and distribute in high burden states as an alternative to depleting resources of liquid medical oxygen. A scarcity of cylinders has also pushed concentrator market, earlier a supplementary medical equipment, at the forefront for home isolated patients and moderate patients in hospitals. But using the correct specification is important.
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Only mild to moderately ill patients, who have an oxygen saturation level between 90-94, should depend on an oxygen concentrator and can use it at home. Because there is scarcity of oxygen, even those with oxygen level as low as 85 can opt for one. Anyone with oxygen saturation depleting below 80-85 may need higher flow of oxygen and will have to switch to a cylinder or liquid medical oxygen supply.
“Say if a person’s oxygen saturation is 87 to 90 and he is put on a oxygen concentrator. If the oxygen saturation rises and maintains between 92-94 that means the concentrator is able to help. But if patient’s oxygen saturation continues to deplete, that means he will need to switch to a cylinder with higher oxygen flow or get hospitalised,” physician Dr Shahid Barmare says.
An inflamed lung infected by Covid-19 is unable to use atmospheric air (that has 21 per cent oxygen) to draw enough oxygen. External oxygen support makes the job easier for lungs.
Also, steady electricity supply is a must. If you live in a place with frequent power cuts, you may want to look for an oxygen cylinder.
There are two types— continuous flow and pulse dose. Continuous flow oxygen will provide the same flow of oxygen every minute unless it is turned off irrespective of whether patient is breathing it in or not, while pulse dose oxygen concentrator detects breathing pattern and dispenses oxygen when it detects inhalation. The oxygen dispensed per minute will vary in second case.
First lets understand how oxygen supply works. Barmare says normal air will have 21 per cent oxygen. Concentrator will suck in atmospheric air, filter nitrogen and other gases, and compress remaining oxygen and dispense it through cannula. “If f 1 litre oxygen is provided to patient through concentrator, the oxygen percentage (or fraction of inspired air) in lungs rises to 24 per cent, with 2 litres it rises to 28 per cent and with 10 litres it rise to 60 per cent. Depending on need, the litres of oxygen per minute have to be regulated,” Barmare explains.
A physician’s advice is necessary to decide how many litres per minute of oxygen is required, a pulse oximeter should be handy. Oxygen concentrators can supply between 0.1 litres per minute (LPM) to 5 to 10 LPM. A concentrator has 92-95 per cent pure oxygen.
Mohammed Ashraf, a supplier, says it depends on number of sieves/ filters in concentrator that affect its oxygen quality output. The purer the oxygen output, the better its result in improving oxygen saturation level in patient. “A concentrator’s output is not measured by its weight, it is measured by LPM output,” he said.
“If concentrator gets overheated output of oxygen purity will reduce. So patient must use only as much oxygen as needed, not an overdose,” Ashraf said.
A lightweight device, weighing less than 27 kg, is recommended. Oxygen concentrators are available as 3, 5, 8 and 10 LPM units. Most common is 3 or 5 LPM. A 10 LPM can be used for two patients who have low oxygen requirement. A 5 LPM will cost Rs 40,000-60,000 and a 10 LPM can cost upto Rs 1.60 lakh.
Sunil Khurana, CEO and MD of domestic manufacturer BPL Medical Technologies, said it is a common practice in China for those aged over 65 years to keep a concentrator at home. Khurana said 3 LPM is ideal for mild to moderate patients. “Oxygen concentrator is a home care product, and ideally not a hospital product. In desperate situation it is used in hospitals. In my understanding in 95 per cent cases, 3-5 LPM capacity is most ideal with approximately 90% oxygen purity,” he said.
Khurana added that a “poor quality” concentrator (several are now imported from China and cost less) can give poor output even if specification are 10 LPM. “So check the supplier’s credentials,” he said.
Phillips, BPL Medical Technologies Ltd, Invacare, AirSep corporation, SS Technologies, Oshocorp Global Pvt Ltd, Medtronic, Inogen, Nidek Medical, Chart Industries are some common importers and manufacturers in India.