Discussion
The world is currently facing many challenges associated with the COVID-19 pandemic and its potentially devastating systemic health effects. The disease affects several body systems (i.e., respiratory, cardiovascular, renal, hematological, neurological) with consequences that manifest in multiple dimensions: mental health and substance abuse issues, job loss, and social inequities.[11][12] Clinicians are seeking alternative strategies to manage the disease before it progresses into severe ARDS, invasive mechanical ventilation, and increased mortality rates.[4][13] Prone positioning is a life-saving intervention recommended in evidence-based guidelines for managing patients with ARDS as it reduces the risk of VILI and improves respiratory mechanics.[14][15]
The data from our study on awake self-proning raise several points for discussion. The R2 values for the change in SpO2 that occurred during a proning event (stomach or lateral) reflected the linear relationship between the DV (change in SpO2) and the IV (prone position). The percent variation in the data for the nonintubated population for both stomach and lateral proning was < 0.1%, and for the intubated population, it was > 1% for both body positions (stomach 2.8%, lateral 1.1%). The low effect sizes for these variations may be due to outliers or the exclusion of other variables such as patient comorbidities. Additionally, the t -stat values for the change in SpO2 during stomach proning events for both populations and lateral proning in the intubated population were low (all were < -2.0, p <0.05). For the change in SpO2 during lateral proning in the nonintubated population,t -stat was > -2.0, p 0.055. The absolutet -stat values were less than the df for both stomach and lateral proning in both populations. Based on the results, we can conclude that a significant difference exists between the change in SpO2 before proning and when a nonintubated patient assumes the stomach position and when a patient who was subject to intubation engages in either stomach or lateral positioning.
Although self-proning is widely practiced as a standard of care for improving oxygenation, it is uncertain how long the effects last, if it accelerates recovery time, and if it decisively prevents or delays the need for intubation.[16] Reports indicate that proning longer throughout the day decreases the risk of lung damage.[16] The patients in our study engaged in short-term proning (stomach and lateral), but the long-term effects are not apparent. We included data for lateral positioning because of patient preference and that it is associated with drainage of lung secretions and improvement in pulmonary gas exchange in critically ill patients.[17] Based on our data, lateral proning was more effective in the patients who were later intubated than those who did not undergo mechanical ventilation. This may be due to other unexplored conditions, such as differences in disease states and medications. It is also important to note that the requirement for mechanical ventilation for the intubated patients in this study (16% of the total population) cannot be related to a single proning event. These patients were independent and able to perform awake self-proning before intubation. The patient protocol was to change positions every 2 hours (stomach, right and left lateral, and sitting up); however, proning events were inconsistent and based on the patient’s tolerance and position preferences. As a result, it is unclear if more consistent self-proning would have decreased the incidence of intubation in the patient population. A dedicated team who could consistently monitor the independent awake self-proner throughout each shift during their hospital stay would help minimize or avoid non-conforming proning times and events.
Our study population (N=93) is one of the largest in size in the area of self-proning in COVID-19 positive patients over a one-year interval. The candidates for this minimal risk intervention were acutely suffering SOB from the systemic effects of COVID-19, and the results from this study indicated that changes in SpO2 were significant when self-proning on the stomach or in the lateral position. The lack of consistency in our data may weaken the argument for short-term and long-term proning as a potential rescue intervention; however, based on the results, self-proning (stomach or lateral) resulted in improved gas exchange and was widely and effectively utilized in accordance with safety guidelines during the pandemic throughout the hospital where this study took place. Although the benefit of proning in the nonintubated patient may not be solely related to improved oxygenation, it is advantageous as a low-cost, scalable intervention that is easily implemented and may save the lives of those at risk of intubation.[18] When safely guided and controlled, proning may be beneficial as a rescue strategy and may help avoid endotracheal intubation and its potentially harmful effects on hypoxemic COVID-19 patients.[16]