This research matters to people who have been critically ill with COVID-19 and their families. During the pandemic, many patients with severe lung failure, called acute respiratory distress syndrome (ARDS), needed a breathing machine. A common treatment was 'prone positioning'—carefully turning patients onto their stomachs to help their lungs work better. Doctors have debated whether keeping patients in this position for longer periods is more helpful. This review aimed to find an answer by looking at all the available research, which could help guide care for future patients with similar severe lung conditions.
The researchers conducted a systematic review and meta-analysis, which means they carefully searched for and combined the results of all relevant studies on this topic. They focused on adult COVID-19 patients with moderate-to-severe ARDS who were on breathing machines. In total, they analyzed data from 996 patients across seven studies. Of these patients, 592 received 'prolonged' prone positioning, where the average session lasted more than 24 hours. The other 404 received 'standard' prone positioning, with sessions lasting 24 hours or less. It's important to note that six of the seven studies were observational, meaning researchers watched and recorded what happened in real-world care, rather than actively assigning patients to different groups in a controlled experiment. Only one was a randomized controlled trial, which is considered the strongest type of evidence.
The analysis found several key results. First, there was a non-significant trend suggesting that longer prone sessions might be linked to lower mortality. The death rate was about 34% in the prolonged group versus 40% in the standard group. However, the statistical analysis showed this difference could easily be due to chance, so it cannot be considered a proven benefit. More clearly, oxygen levels improved significantly during and after the longer prone sessions. On average, a key measure of oxygen in the blood was about 17 to 24 points higher in the prolonged group, which is a meaningful short-term improvement for the lungs. On the safety side, there was a borderline significant increase in pressure injuries (like bedsores) with longer positioning—about 30% of patients in the prolonged group experienced them compared to 26% in the standard group. There were no clear differences in how long patients stayed in the ICU or in other breathing machine settings.
The most important caveat is that the evidence remains inconclusive. The researchers performed a 'trial sequential analysis,' a statistical method that checks if enough patients have been studied to draw a firm conclusion. This analysis confirmed that the current total evidence is insufficient to reliably confirm either a benefit or a harm from prolonged prone positioning. The findings, especially the trend in mortality, need to be viewed with great caution because most of the data comes from observational studies. In such studies, other factors besides prone positioning time could explain the differences in outcomes. The single randomized trial included was not large enough to settle the question on its own.
Regarding safety, the main concern noted was the potential increase in pressure injuries. Turning critically ill patients requires a skilled team to prevent complications like skin breakdown, nerve injuries, or accidental tube dislodgement. While this review specifically highlighted pressure injuries, the general risks of prone positioning are well-known to ICU teams. The analysis did not report on other specific adverse events, serious adverse events, or how many patients could not tolerate the procedure, which is a limitation.
What does this mean for patients right now? For individuals currently in the hospital, decisions about prone positioning—including how long each session lasts—will continue to be made carefully by the intensive care team based on the specific patient's condition, hospital protocols, and the latest guidelines. This review does not provide definitive proof to change standard practice. It suggests that longer sessions might offer a lung oxygenation advantage, but with a potential trade-off of more skin injuries. It strongly highlights the need for more high-quality, randomized controlled trials to get a clearer answer. For now, this research adds a piece to the ongoing medical discussion but is not a practice-changing conclusion.