Introduction
The COVID-19 pandemic in 2021 has accelerated the demand for oxygen supplies globally.
Many countries have not seen such high demand before the pandemic to meet their daily
oxygen requirement (Usher 2021). Worldwide, governments are scaling up their existing
facilities to fill the oxygen demand. In the healthcare system, oxygen is an essential
medicine required at all levels. It is estimated that 20–40% of deaths due to pneumonia
could be prevented using oxygen therapy (WHO 2021). Medical air in hospital settings
is widely used for mechanical ventilation, infant resuscitation, aerosol drug delivery,
and neonatal environment control (Edwards et al. 2018).
Oxygen cylinders, oxygen concentrators, liquid oxygen, and membrane separator oxygen
enrichers are commonly used for oxygen therapy (Rees and Dudley 1998). In the current
COVID-19 pandemic, long-term oxygen therapy is required at both hospitals and in-home
settings that the respiratory physician should supervise for optimal treatment (Rees
and Dudley 1998). Unprecedented production of oxygen and refilling of cylinders can
give rise to the risk of impurities, which could lead to an increase in hidden mortality.
However, it would be difficult to assess the increase in mortality due to the impurity
of the oxygen gas. Hence, the purity of the oxygen needs to be regulated by the respective
authorities (Edwards et al. 2018). Higher oxygen production can give rise to a possibility
of contamination.
In a recent study, the CO2 impurity was reported in oxygen cylinders above the recommended
threshold level (Edwards et al. 2018). In previous studies, various health effects
were reported due to the common air pollutants (WHO 2005). It was also observed that
unintentional inhalation of NO in industrial regions might change the PaO2 (Benzing
et al. 1999). Edwards et al. (2018) also mentioned onsite production of medical air
poses a risk of raising the CO2 and NOx (nitric oxides) concentration above the United
States Pharmacopeia (USP) threshold (Edwards et al. 2018). This rise of these trace
gases may be due to the dryer that is used to capture the CO2 contaminant and humidity.
Impurity sources can be arising due to the production and delivery systems, as well
as from the environmental pollution levels near the regions. According to the FDA
guidelines, medical gases should be checked for any adulteration during production,
packaging, delivery, and manufacturing facilities (FDA 2015). Here, we would like
to highlight few points for policymakers/local authorities (Table 1) and for the general
public (Table 2) to create awareness and recommendations to improve the quality of
oxygen.
Table 1
Interventions required by policymakers or local authorities
Monitor gas testing facilities, laboratories, and calibration facilities at the site
To ensure compliance and procedures of finished gas for its quality
Purity and grade (ultra-pure, 99.999% minimum) should be maintained
A random check of tankers and especially cylinders for chemical analysis of oxygen
gases
Impurity parameters certificate should be provided for the levels (i.e., carbon monoxide/carbon
dioxide, moisture, arsenic, oil, halogen, oxidizing substances, acidity or alkalinity,
argon, hydrocarbons)
Test results can be cross-checked by the local authority for any foreign materials,
moisture, and contaminants
To monitor any misuse of other cylinders (i.e., helium, hydrogen, acetylene, argon)
for refilling oxygen without proper cleaning and conditioning
Monitoring for the sanitization of oxygen supply (pipeline and tubes) for unwanted
fungal growth
Special attention should be given to test “black fungus” (mucormycosis) infection
among recovered patients
Checking/advisory for black fungus on patients on oxygen support should be made an
essential part of the COVID-19 control protocol at every level
Special attention/care should be given to comorbid and patients using the steroid
to check the fungal infection for the hidden cause of death
Table 2
Recommendation/awareness needed for the general public
Oxygen gas cylinder should be kept at normal room temperature
Always use distilled water to make oxygen hydrated before use
Never use poor-quality water such as tap water, boiled water, or purified RO water
Masks, nasal cannulae should be cleaned and checked for any leakage by the attendee
If using an oxygen concentrator, attendee should adhere to manufacturer guidelines
for proper cleaning as and when required
The oxygen concentrator should be placed in a well-ventilated and clean area
Oxygen filters should be properly cleaned from time to time
Avoid smoking (wood, cigarette, sticks) in any form, active or passive, near to oxygen
concentrator
Attendee can monitor patient nostril for any black pigmentation, as soon as it is
noticed even as the smallest spot contact doctor immediately for further treatment
Avoid irrational use of steroids without recommendations
Another reason for the increase in the COVID-19 mortality can also be due to the black
fungus, which are present in the environment (Richardson 2009). This could lead to
mucormycosis, which could be a fatal disease for people who have weakened immune systems
(Spellberg et al. 2005). In the nasal tract, black fungus develop due to the poor
quality of water used to hydrate the oxygen in a hospital setting (piped and cylinders).
This fungus grows in the nostril, travels towards the eyes (Klotz et al. 2000), and
then towards the brain, which can paralyze the nerves (Escobar and Del Brutto 1990),
cause permanent damage to the eye, or even could lead to a heart attack (Naik et al.
2021; Jackman and Simonsen 1992).
An evidence-based advisory for screening, diagnosis, and management of mucormycosis
developed by Cornely et al. (2019) should be followed and need to be updated considering
the recent evidence of mucormycosis in the COVID-19 pandemic (Cornely et al. 2019).
In a hospital setting, constantly monitor distilled water for oxygen hydration before
using it in oxygen therapy devices (Cahill and Heath 1990). Use of tap water even
after boiling is not recommended in the humidifier as after some time; impurities
(micro-metals and minerals/salts) start to buildup, leading to severe health issues
even after using life-saving precious oxygen therapy.
Globally, we are facing an emergency that needs support from authorities and the community
to minimize the suffering and improve the well-being of all. In lower- and middle-income
countries, oxygen purity can be a significant issue that requires local interventions
at the earliest. Countries where there is prevalence of malaria, sepsis, pneumonia,
and other ailments should also prioritize where oxygen therapy requires at large (Usher
2021).