The following is a summary of “Prognostic value of PaO2/FiO2 ratio in predicting clinical outcomes in COVID-19 patients,” published in the June 2024 issue of Critical Care by Canto-Costal et al.
The PaO2/FiO2 (P/F) ratio is used to evaluate oxygenation in patients with COVID-19.
Researchers conducted a retrospective study evaluating the prognostic significance of the P/F ratio regarding disease severity, length of hospital stay, and mortality.
They evaluated data from 753 patients admitted for COVID-19 at a Houston, Texas hospital (March 2020 and February 2022). Patients were stratified into four P/F ratio groups based on the Berlin Criteria (P/F ratio): severe (<100 mmHg), moderate (101-200 mmHg), mild (201-300 mmHg), and normal (>300 mmHg). Statistical analyses were performed using IBM SPSS Statistics 25.0 software. The specific tests (descriptive statistics, chi-square, logistic regression) were employed to assess the relationships between the P/F ratio and various clinical outcomes.
The result showed 753 patients with a median age of 56 (44-66.5 years) and a median hospital stay of 7 days (4-13 days). The median P/F ratio was 252 (149-328.50). Males comprised 57.5% (433), with a survival rate of 43.5% (320). Patients were stratified into 4 groups based on P/F ratio – group 1 included 125 patients (16.6%), group 2 included 166 patients (22%), group 3 included 196 patients (26%), and group 4 included 266 patients (35.3%). Chi-square analysis revealed a statistically significant correlation between P/F ratio and clinical outcomes (P<0.0001). Mortality rates mirrored P/F severity, group 1 had the highest mortality (74, 48.7%), followed by group 2 (47, 30.9%), group 3 (17, 11.2%), and group 4 (14, 9.2%). Gender also showed a specific association with P/F ratio (P<0.0001). Group 1 had the highest percentage of males (72%), followed by group 2 (55%), group 3 (61.6%), and group 4 (49.2%). Logistic regression analysis (P<0.05, 95% CI) identified male gender (P=0.041), group 1 (P<0.001), and group 2 (P<0.001) at a significant risk for mortality among all groups. Group 3 shows a protective effect (P=0.371), suggesting a lower risk of death with a Wald test score of 0.800. Finally, the analysis revealed a positive correlation between length of stay and mortality risk (P=0.007). The results highlighted the P/F ratio as a strong predictor of clinical outcomes in patients with COVID-19, with a Wald score of 59.075 (P<0.001).
Investigators concluded that a strong association was observed between P/F ratio, clinical outcomes, gender differences, and extended hospital stays among patients with COVID-19.
Source: criticalcareshock.com/2024/06/12590/
