COVID-19 complications: High oxygen flow from ventilators changes microbiota, makes lungs vulnerable to damage

It is an established fact that older people and people with comorbidities are at higher risk of developing severe symptoms of COVID-19. The severe symptoms include extreme difficulty in breathing, extreme pain in the chest, delirium and bluish discolouration of the face and lips. All these symptoms can lead to respiratory complications such as viral pneumonia and pulmonary embolism, thus requiring mechanical ventilation for breathing and life support. In a recent article, published in Science Translational Medicine, scientists have stated that the high flow of oxygen from the ventilators can result in lung damage. What does this mean for severe COVID-19 patients? What is a ventilator? A ventilator is an emergency respiratory machine which acts as a life support system when the patient is unable to breathe on their own. The function of a ventilator is to bring high flow oxygen to the lungs of the patient and then remove the carbon dioxide from their body. It can be used during a surgery or a lung injury or if the person is in the state of coma. How can ventilators cause damage to the body?  For the study, researchers from the University of Michigan Medical School conducted an experiment on newborn and adult mouse models to establish the effect of high flow oxygen in the body, which is known as hyperoxia. The scientists found that in the critically-ill patients, high flow oxygen from mechanical ventilation promotes the growth of microbes (such as Staphylococcus aureus) in the lungs which can result in pneumonia and abscess. Scientists also found that when the mice experienced hyperoxia, there was a change in the bacteria present in the lungs and gut of these mice. This disturbance in the lung and gut microbiota (the hub of microorganisms) resulted in lung inflammation and oxygen-induced lung injury. The researchers further stated that oxygen-induced lung injury was less prevalent in the mice who were germ-free and had undergone systemic antibiotic treatment. Is the recovery from ventilators strenuous? Doctors have already reported that people who require mechanical ventilation for a long period of time present with lung damage in the form of pneumonia, pneumothorax (fluid build-up in the lungs), oxygen toxicity and even lung failure. It has been observed that COVID-19 positive patients who required ICU care and ventilator support for breathing, faced various physical as well as mental problems in the longer run. Many of these patients required breathing assistance, either in the form of masks or a continuous positive airway pressure ventilator (Cpap), even after coming off a ventilator. Sometimes, these people require physical therapy to be able to walk, breathe, speak and even swallow again. For more information, read our article on Risks of intubation and ventilators for COVID-19 patients. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.