Increased respiratory drive and effort were essential features of acute hypoxemic respiratory failure (AHRF) and might help predict the need for intubation. For a study, researchers sought to investigate the feasibility of a non-invasive respiratory drive evaluation and describe how these parameters could help predict the need for intubation. Investigators performed a prospective epidemiological study. All consecutive patients with COVID-19-related AHRF who required a high-flow nasal cannula (HFNC) were screened for inclusion. Physiologic data (including occlusion pressure (P<0.1), tidal volume (Vt), inspiratory time (Ti), peak as well, and mean inspiratory flow (Vt/Ti)) were collected during a brief continuous positive airway pressure (CPAP) session. Measurements were repeated 12–24 hours later. After screening 45 patients, measurements were completed in 31 of them (70%). About P<0.1 was high (4.4 [2.7–5.1]), but it was not significantly higher in intubated patients. Intubated patients had higher Vt (P=.006), Vt/Ti (P=.019), minute ventilation (P=.006), and Ti/Ttot (P=.003) values than non-intubated patients. Over time, intubated patients’ diaphragm thickening fraction, Vt, and Vt/Ti increased significantly. Non-invasive assessment of respiratory drive in patients with AHRF was possible and revealed an increased P<0.1, but it was not predictive of intubation.
Source:www.sciencedirect.com/science/article/pii/S088394412200048X