Should people who are on ventilators in the ICU be placed on their backs or their stomachs? In the medical vernacular that would be supine (face up) or prone (face down), and at first glance it really seems like such an academic question, as Rick and I discuss on PodMed this week, and that's because of course nearly everyone we've ever seen in an ICU is face up, or supine, thus allowing medical personnel easy access to tubes and drains and EKG leads and all those trappings of intensive medical caretaking. And anyone who's visited someone in an ICU wants to see their face, not the back of their head. So what's with this study in none other than the august New England Journal of Medicine?
'Prone Positioning in Severe Acute Respiratory Distress Syndrome' proves it's our bad. Turns out that it has been known for some time now that when people have severe acute respiratory problems, being placed in a prone position improves oxygenation and may reduce ventilator-induced lung injury, yet such observations in previous research did not translate into better outcomes. This study prospectively randomized adults with severe acute respiratory syndrome who had been intubated for less than 36 hours and whose oxygen saturation and tidal volume indicated considerable compromise to be placed either supine or prone. A total of 466 patients were randomized, with 237 ultimately in the prone group and 229 in the supine group. Those receiving prone ventilation were required to remain in that position for 16 hours a day.
The differences in outcome were striking. The 28 day mortality for those who received prone ventilation while in the ICU was 16.0%, contrasted with 32.8% among those in the supine position. The unadjusted mortality at 90 days was 23.6% in the prone group versus 41.0% in the supine group, and those in the prone group also experienced fewer cardiac events. Hmmm. Seems like a win-win for prone positioning. The authors most helpfully include a video on the NEJM website so practitioners can see how it's done; clearly experienced teamwork is needed, with three or four people required to successfully reposition the patient, but it does look fairly straightforward. As I comment in the podcast, since we know that severe respiratory compromise is one of the features that accounted for the staggering death toll in the 1918 flu pandemic, I for one am glad that investigators are attempting to assess how to achieve the best outcome under the circumstances. It reminds me of that adage "prepare for the worst and hope for the best" as we're all watching for the emergence of another severe flu.
Another take home message that seems clear is that a priori assumptions about best practices are suspect at best. As we see more evidence emerging about the dangers of transfusions, maybe even those with hematocrits in the basement should be left to their own devices. Ditto for tight management of glucose in folks in the ICU, immobilization on backboards before transport of those injured in the field and transported to the ICU, and on and on...sacred cows are being felled in all directions, lending credence to our new mantra: evidence-based medicine. Stay tuned.
Other topics this week include implanted cardiac defibrillators and sports risk in Circulation, short term versus longer term steroid use in COPD in JAMA, and assessing the benefit of prostate cancer treatment in Annals of Internal Medicine. Until next week, y'all live well.