Risk factors for prolonged intensive care unit and hospital stay among patients with acute drug overdose in Japan.

Aim: Hospital selection for patients with drug overdose (DOD) is a critical issue. In Tokyo, the 50-tablet rule has been widely utilized by paramedics for triaging patients with DOD given that it shortens the triage time. However, studies have not investigated the utility of such a rule in local cities. The present study aimed to identify prognostic pre- and in-hospital factors among patients with DOD and determine whether the 50-tablet rule benefits local cities.

Methods: Clinical records of patients with DOD admitted at the University of Tsukuba Hospital (Tsukuba, Japan) between 2013 and 2017 were retrospectively reviewed.

Results: A total of 93 patients with DOD were enrolled in this study. Multivariate analysis showed that creatine kinase and C-reactive protein values and the total number of ingested pills were in-hospital risk factors that significantly prolonged intensive care unit (ICU) and hospital stay. Moreover, Glasgow Coma Scale score on admission and the total number of ingested pills were identified as significant pre-hospital risk factors for prolonged ICU and hospital stay. Setting the total number of ingested pills to 50 tablets did not significantly influence ICU and hospital stay.

Conclusion: The total number of ingested pills and creatine kinase and C-reactive protein values were identified as predictive factors for prolonged ICU and hospital stay in patients with DOD after admission. Moreover, pre-hospital risk factors included Glasgow Coma Scale score and the total number of ingested pills. However, the 50-tablet rule was determined to be a poor cut-off value for patients with DOD. We presented a subset of our findings at the 46th annual meeting of the Japanese Society for Acute Medicine (Yokohama, Japan) on 20 November 2018.