Background:The number of patients requiring mechanical ventilation (MV) is increasing worldwide. Patients requiring MV are commonly managed in an intensive care unit (ICU); however, Japan is unique in that many of these patients are treated in non-ICU settings. The characteristics of these patients, nevertheless, are unknown. We sought to identify disease severity and MV settings of patients in non-ICU settings in Japan.Methods: We retrospectively analyzed the clinical data of Kinan Hospital and Owase General Hospital, where there are no ICUs or ICU physicians. Data for adult patients who required MV for more than 3 d from January through December 2018 in those hospitals were collected.Results:A total of 171 patients received MV; 29 patients were treated for more than 3 d. Of that subset, the mortality rate was 44.8% (13 patients). Thirteen patients survived to discharge, and three were transferred to a higher-level facility. The median age of patients treated for more than 3 d was 80 (72–84) years. The mean Acute Physiologic Assessment and Chronic Health Evaluation II score was 20.9 ± 8.1, and predicted mortality was 0.42 ± 0.25. Tidal volume per predicted body weight was 8.8 ± 2.1 mL/kg; set inspiratory time was 1.6 ± 0.3 sec. Preventable non-ICU death (patients who might have been saved if treated in an ICU setting), was 10.3%.Conclusions:The overall mortality of patients treated with MV in a non-ICU setting in the East Kishu area was not inferior to the mortality if they had been treated in an ICU; however, MV settings should be improved.