Characteristics and progress of ICU subjects with acute respiratory distress syndrome according to the ventilatory ratio
A retrospective analysis
Abstract
Objectives: To describe the characteristics and progress of subjects diagnosed with acute respiratory distress syndrome (ARDS) at intensive care unit (ICU) admission and requiring mechanical ventilation (MV), according to the ventilatory ratio (VR) cut-off point (high VR ≥2 or low VR <2).
Materials and method: A retrospective, descriptive, and observational study was conducted on subjects over 18 years of age, requiring MV, and diagnosed with ARDS at ICU admission. Data were collected from our database between July 2020 and May 2021.
Results: Of the 50 subjects included, 19 had a high VR. The median age was 57 years (IQR 47.8-64), and 62% were male. Significant differences were found between the groups in the Charlson Comorbidity Index (CCI; p=0.04) and arterial pressure of carbon dioxide (PaCO2; p=0.002). Of the total subjects, 18 (36%) were extubated: 6 (12%) failed extubation, 10 (20%) required a tracheostomy, and 31 (62%) died. Significant differences were found between the groups in the number of extubations (p=0.03) and mortality (p=0.02).
Conclusion: The progress of subjects was different depending on whether they had a high or low VR, measured in the first 24 hours of ICU admission. In the high-VR group, fewer subjects were extubated and mortality was higher.
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