PRONE VENTILATION IN PATIENTS WITH ARDS


 Introduction
 Prone ventilation has been a a tool that has been shown to improve oxygenation and ventilatory mechanics in patients with Down syndrome acute respiratory distress (ARDS). Although be a technique that has been performed for decades in the field of intensive care has been with the pandemic generated by COVID-19 when it has returned to be in the spotlight. However, the lack of standardized protocols make it difficultestablish when ventilation should be performed in the prone position, so this little review tries to outline some indications of when it should be done.
 
 Methodology
 Two recent meta-analyses have been reviewed. about the effects of prone ventilation based on randomized controlled clinical trials of ventilation in the prone position.
 
 Results
 The results of the meta-analyses show that there are certain circumstances which must be given to maximize the beneficial effect of pronation and that it has a beneficial effect on survival of patients with ARDS. First of all, when separated the groups according to whether they had performed lung-protective ventilation or not, the OR of the group prone was 0.58 (95% CI 0.38-0.87) and 0.70 (95% CI 0.47-1.04), so prone ventilation does achieve a decrease in mortality when it is associated with lung-protective ventilation. Another variable that observed in this meta-analysis was the length of time prone, since when this was greater than 12 hours a day the OR of the prone group in terms of mortality vs. supine was 0.60 (95% CI 0.43-0.83) and 0.74 (95% CI 0.56-0.99). When the time was less than 12 hours these beneficial effects on mortality are they dissipated Thirdly, the "timing" was also studied. Of pronation since when it was established in the first 48 hours after ARDS diagnosis, the OR was 0.49 (95% CI 0.35-0.68), beneficial effect that was lost when it started after the first 48 hours. Finally, the severity of ARDS was also assessed (measured in PaFi), observing that patients with severe ARDS (PaFi < 100) achieved a decrease in mortality with an OR of 0.51 (95% CI 0.36-0.72), and this effect the benefit was not achieved in moderate ARDS (PaFi 100-200). The second meta-analysis shows results similar, although this compares the mortality of Moderate-severe ARDS (PaFi <200) with the rest of ARDS, obtaining a reduction in mortality With an OR 0.74 (95% CI 0.56-0.99)
 
 Conclusions
 Prone ventilation can have effects beneficial in the survival of patients with ARDS and it is important to know what conditions you should to have to achieve this effect. If we rely on the results of the latest meta-analyses, it should be recommended its use in patients with moderate-severe ARDS (PaFi < 200), associated with low tidal volumes (ventilation of lung protection with VC < 8cc/kg of ideal weight), for more than 12 hours a day and establishing it in the first 48 hours from the diagnosis of ARDS.
