Introduction:
The Coronavirus disease caused by severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) has made a considerable impact and is still a problem of concern even after almost two years. The increased disease exposure to the people leads to a scarcity of ICU beds and mechanical ventilators. Therefore, to prevent the death rate due to limited resources, intubation and mechanical ventilation are required. A recent study showed that mechanically ventilated patients with COVID-19 associated acute respiratory distress syndrome (ARDS) showed up with:
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Low respiratory rate - Supine position.
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Improved oxygenation and increased lung recruitment - Prone position.
So, randomized controlled trials can help to better understand the benefits and risks of prone positioning in patients with COVID-19 who are breathing normally.
What Are the Indications and Contraindications of Prone Position?
1) For Severe Acute Respiratory Distress Syndrome - Prone positioning is standard practice for patients with ARDS with mechanical ventilation as it improves the PaO2/FiO2 ratio and reduces the death rate in patients with ARDS who are in the critical care setting.
2) For Hypoxic Respiratory Failure - Prone positioning helps with patients who are,
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Awake.
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Breathing without any apparent external cause.
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Non intubated.
3) For COVID-19 Pneumonia - Prone positioning has the potential to improve oxygenation and decrease dyspnea (shortness of breath) in COVID-19 pneumonia cases.
4) For Mechanically Ventilated Patients - Prone positioning does not help these people as they can cause dislodgement of endotracheal tubes, and risks related to pressure are less severe.
How Does Prone and Supine Positions Affect Lung Function in COVID-19 Patients?
Prone positioning is positioning a patient's face down on their chest and abdomen to improve oxygenation and decrease lung injury.
In the Prone Position - Lung compliance is improved because other organs exert a reduced force on the lungs. The following are the alterations in the forces:
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The decreased gravitational force of the heart and mediastinum on the lungs.
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Decreased compressive effects of the abdominal organs on the lungs and equal distribution of forces on the lungs by the diaphragm reduce lung injury during mechanical ventilation and breathing without any external cause.
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More homogenous chest wall compliance due to restriction of anterior chest wall movement.
In the Supine Position - There is increased force from other organs to the lungs, such as,
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Gravitational pressure of the heart and mediastinum on the lungs.
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Compressive effects of the abdominal organs on the lungs displace the posterior diaphragm superiorly, which causes posterior lung collapse.
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Expansion of chest wall and less homogenous chest wall compliance.
When patients with severe acute respiratory distress syndrome (ARDS) supine position, it can result in:
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Increased pulmonary edema.
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Complete or partial collapse of a lung.
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The collapse of a section of a lung.
What Are the Eligibility and Non-Eligibility Criteria for Prone Positioning?
Before the COVID-19 pandemic, prone positioning was practiced chiefly for patients with severe ARDS. During the COVID-19 pandemic, the healthcare physicians did not know how to overcome this infectious disease with acute respiratory failure, and there were reports where prone positioning helped patients with COVID-19. Several studies showed that prone positioning improves oxygenation for non intubated COVID-19 patients on both low-flow and high-flow oxygen devices and who can tolerate the position. A COVID-19 pneumonia case in pregnant women was reported, and prone positioning on the fetus was successful during pregnancy. Recently several guidelines for prone positioning in obstetrical patients with COVID-19 were developed, and it was successful. The prone position should be avoided for patients with:
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Spine surgery.
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Reduced level of consciousness.
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Worsening hypoxia (low oxygen in the blood).
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Facial trauma.
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Recent abdominal surgery.
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Recent pacemaker insertion.
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Unstable spine fractures.
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Thoracic surgery.
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Pelvic fractures.
What Are the Recommendations for Prone Positioning In COVID-19 Patients?
Prone positioning is recommended in patients with ARDS related to COVID-19. But still, it is unknown whether there are any unique physiological attributes of ARDS associated with COVID-19. Some protocols say that prone positioning is considered for patients with severe ARDS related to COVID-19 because prone positioning is beneficial in the setting of severe ARDS. COVID-19 worldwide has led to various evaluations to beat this pandemic. Out of which prone positioning is evaluated to work,
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Outside the intensive care unit (ICU).
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Medical wards.
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Emergency departments.
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Repurposed surgical floors.
It was noticed that prone positioning improves oxygenation for many patients. A study said that patients with COVID-19 who were awake, not intubated, and normal breathing required oxygen supplementation due to hypoxemic acute respiratory failure These patients were followed for up to ten days. Out of twenty-four patients in the study,
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Fifteen patients were able to tolerate the prone position for more than three hours.
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Five patients were able to tolerate it for three hours.
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Four patients did not tolerate it for more than one hour.
Patients who tolerated it for three hours had at least a 20 % increase in partial pressure of arterial oxygen (PaO2), and the PaO2 increased from 73.6 mmHg before prone positioning to 94.9 mmHg after prone positioning. In the nonrandomized study, fifty patients received prone positioning in the intensive care unit, and the results were improved when oxygenation was observed within five minutes. However, half of the patients required intubation within three days.
What Are the Complications Associated With Prone Positioning In COVID-19 Patients?
In order to benefit from prone positioning, patient-specific factors must be considered to prevent its complications. Prone positioning worsens chest wall compliance, and complications associated with prone positioning include,
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Increased ventilation pressures.
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Airway obstruction.
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Loss of venous access.
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Hypotension (low blood pressure).
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Endotracheal tube dislodgement.
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Arrhythmias (improper heartbeat).
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Facial and airway edema (swelling or puffiness).
Studies say that there is no difference in the complications between the supine and prone position, and it will be safe only in the hands of experienced clinicians.
Conclusion:
The COVID-19 pandemic has led to a lack of many intensive care resources around the world. As prone positioning was practiced successfully for ARDS, it also helped with COVID-19 patients who are breathing spontaneously and not intubated. However, there are no clinical shreds of evidence regarding the time duration and the safety profile of prone positioning in COVID-19 cases. So a guide by a healthcare professional is needed for starting and stopping the prone positioning. To avoid all these health issues of COVID-19, people should get themselves vaccinated and try to stay indoors as much as possible to prevent infection. Also, follow COVID-19 protocols such as social distancing for up to two meters, frequently washing hands, avoid frequent outings, and touching the face to beat this pandemic.
