Survival predictors after intubation in medical wards: A prospective study in 151 patients

INTRODUCTION: In health care systems in need of additional intensive care unit (ICU) beds, the decision to mechanically ventilate critically ill patients in Internal Medicine (IM) Department wards needs to balance patients’ health outcomes, possible futility, and logistics. We aimed to examine the survival rates and predictors in these patients. METHODS: We prospectively enrolled consecutive patients receiving mechanical ventilation during their care in the IM wards of a tertiary University hospital between April 2016 and December 2018. Primary outcome was 90-day mortality and secondary outcomes were in-hospital mortality and ICU transfer. RESULTS: Our cohort consisted of 151 unique patient intubations, of whom 74 (49%) patients were transferred to ICU within a median of 0 days (range 0–7). Compared to patients who remained in the wards, patients transferred to ICU had lower in-hospital and 90-day mortality (65% vs. 97%, and 70% vs. 99%, respectively, p<0.001 for both). Amongst several possible predictors of survival in the ICU, sequential organ failure assessment (SOFA) score at the time of intubation had the best prognostic accuracy with an AUROC of 0.818 and 0.855 for in-hospital and 90-day mortality, respectively. A baseline SOFA score ≤8 had a 100% sensitivity for survival prediction in ICU. However, out of 26 patients with SOFA score ≤8 who remained in the wards, only one survived, whereas 19 patients with SOFA score >8 who were transferred to ICUs received futile care. CONCLUSION: Mortality for patients receiving mechanical ventilation in IM wards is almost inevitable when ICU availability is lacking. Therefore, applying additional transfer criteria beyond the SOFA score is imperative.