Association Between Anemia Severity and Mechanical Ventilation Duration in Patients Admitted to the Intensive Observation Room at Dr. Soetomo General Hospital, Surabaya: A Retrospective Cohort Study

Introduction: Anemia may impair tissue oxygen delivery in critically ill patients, but its association with weaning and extubation outcomes remains unclear. This study examined the association between anemia severity and mechanical ventilation duration at Dr. Soetomo General Hospital, Surabaya. Methods: This retrospective cohort study included 107 mechanically ventilated patients admitted from January to June 2022. Anemia severity was classified by hemoglobin levels on ICU admission day 1. Ventilation duration, from initiation to extubation or death, was categorized as <1, 1–3, 4–7, or >7 days. Analyses used Spearman’s rank correlation and the Fisher–Freeman–Halton exact test with Monte Carlo estimation, including trauma-based subgroups. Exploratory survivor analyses included pairwise Mann–Whitney U tests with Holm adjustment. Results: No significant correlation was found in the overall cohort (ρ = 0.121, p = 0.213; 95% BCa CI: −0.093 to 0.309), trauma subgroup (ρ = 0.018, p = 0.883; 95% BCa CI: −0.237 to 0.275), or non-trauma subgroup (ρ = 0.304, p = 0.053; 95% BCa CI: −0.007 to 0.550). Among 67 survivors, a significant positive correlation emerged (ρ = 0.368, p = 0.002; 95% BCa CI: 0.129 to 0.559). Ventilation duration differed significantly between mild and severe anemia (Holm-adjusted p = 0.009) and moderate and severe anemia (p = 0.012), but not mild and moderate anemia (p = 0.104). Conclusion: No significant correlation was found in the overall cohort or trauma-based subgroups. The positive correlation among survivors should be interpreted cautiously due to potential selection bias. Further studies accounting for confounders are warranted.