New waves of the COVID-19 pandemic in countries like Kenya and India have exposed poor management of oxygen supplies. Moina Spooner from The Conversation Africa asked Professor Trevor Duke, an expert on [oxygen provision] and Editor of the World Health Organization (WHO) Guidelines on Oxygen Therapy for Children to provide insight into what countries with limited resources can do to ensure better care.
Why is oxygen so important in treating COVID-19?
The SARS-CoV-2 virus causes COVID-19 pneumonia and hypoxemia. Hypoxemia is a lack of oxygen in the blood – the main complication of COVID-19 pneumonia and a leading cause of death.
Some antiviral drugs have been effective in treating COVID-19 infections. However, in severe pneumonia, oxygen relieves hypoxemia. There may be time for the infection to clear and the lungs to heal. For many people affected by COVID-19, oxygen is life-saving.
What are the challenges in providing oxygen to patients?
Low- and middle-income countries face major hurdles when it comes to providing oxygen to patients. In many countries, adequate oxygen systems have been neglected for decades, although pneumonia was the leading cause of hospital admissions in low and middle income countries even before the pandemic.
An oxygen system contains the equipment needed to detect hypoxemia and deliver oxygen. This contains; A small device called a pulse oximeter, which is essential for detecting hypoxemia, the source of oxygen (for which there are several options), other technical oxygen supply devices (such as flow meters and oxygen tubes), a small device called an oxygen analyzer (which determines the purity of the oxygen rated by the source) and a power supply. In addition, trained health workers, biomedical technicians, and equipment maintenance are vital.
The neglect of oxygen systems was partly market failure, partly lack of knowledge and anticipation, and partly inertia.
In healthcare without effective oxygen systems, there are usually other critical services that are required for the safe operation of a hospital, such as: B. Power supply, water supply, sanitation and infection control, not adequately equipped.
By the time of the pandemic, some governments may not have fully realized that oxygen is life-saving. Or they weren't prepared to invest in a properly functioning oxygen system.
Finally, the development and expansion of oxygen has been given low priority compared to new drugs that can be patented and big pharmaceutical companies can make a big profit.
Robust oxygen systems that would support a pandemic take time to get set up. The basics are the source of oxygen, and the options include gas cylinders, oxygen concentrators, and oxygen generators.
Transporting oxygen cylinders from many private providers in large cities, especially to remote hospitals, is logistically difficult and expensive. A single cylinder of oxygen that would feed a person can last anywhere from 24 to 72 hours, depending on the severity of the hypoxemia and the oxygen demand needed. However, people with severe COVID-19 often have hypoxemia for more than a week, which can cause a cylinder to go out.
Oxygen concentrators are small bedside machines. They take in atmospheric air and remove nitrogen (78% of the air), leaving almost pure oxygen. They have been developed commercially for the home care of adults with chronic lung disease in North America and Europe. They have been effectively providing oxygen to hospitals in low and middle income countries since the 1990s.
Oxygen concentrators can deliver oxygen to up to five children or one or two sick adults at the same time. They represent a continuous source of oxygen that is taken from the air and therefore does not need to be topped up. They're relatively cheap (around $ 500 to $ 1000) but require reliable power (they can be solar powered), some staff training, and maintenance. They are made in many places including the United States, Europe, China, India, and Russia.
Oxygen generators are another way of providing oxygen. These are large machines that generate oxygen from the air (approx. 5000 liters per hour) and can fill between 30 and 50 bottles per day. Oxygen generators are expensive (about $ 100,000) and require a trained biomedical technician. However, they are a long-term investment. They have been used in Asia, Canada and, more recently, Papua New Guinea. They are made in China and the USA. Some are manufactured fully set up and can be shipped to hospitals. All you need is an electrical outlet and a trained biomedical technician to operate it.
A major advantage of oxygen generators and concentrators is that they can supply an entire region or health service in a way that can be independent of private gas companies.
What can be done to improve the situation?
Every situation will be different. In order for an oxygen system to be developed, the local context must be well understood. This includes the systems already in use, the local providers, the capacity of the biomedical technicians, the reliability of the power supplies (often the power supplies are erratic and voltage spikes can damage concentrators, the solar energy is more stable) as well as the size of the local population and the projected values of oxygen demand.
For example, a medium-sized district hospital (which treats 15 to 20 patients with oxygen every day) requires more than 40,000 liters per day. To meet this need, the provision of oxygen should be done through the use of oxygen concentrators and oxygen generators, with some cylinders used for immediate emergencies, e.g. B. for transport in an ambulance.
Can immediate steps be taken?
Currently, governments and health services should invest in bedside oxygen concentrators and generators to meet all hospital or district needs. Global agencies should support this in a similar way that vaccines are expanded through global partnerships like COVAX.
There are many global manufacturers of oxygen concentrators and oxygen generators and there are WHO specifications for these devices. The supply is currently scarce, but production is increasing. India recently announced the import of 10,000 oxygen concentrators.
Healthcare and its partners should run training programs for healthcare workers on the use of oxygen technology. With good planning and management, this can be done in a relatively short time.
In many situations, the use of mechanical ventilators – machines that supply positive pressure to a patient's airways and lungs through a hose – is not appropriate. They require sedation or anesthesia, close monitoring in an intensive care unit, and the ability to identify and manage complications, including the effects on the cardiovascular system, a key characteristic of advanced COVID-19 infection. The drive to purchase mechanical ventilators can be a distraction from increasing the oxygen supply.
Therefore, the priority should be to increase oxygen levels and the quality of care and monitoring. There are ways and models for doing this, even in the most under-resourced health care facilities.
COVID-19 is a long game; The best time to implement effective oxygen systems may have been a few years ago, but the next best time is now.
Trevor Duke, Director of the Center for International Child Health at the University of Melbourne
This article is republished by The Conversation under a Creative Commons license. Read the original article.