AbstractUnplanned extubation (UE) may cause considerable adverse effects in patients receiving mechanical ventilation (MV). Previousliterature showed inconsistent prognosis in patients with UE. This study aimed to evaluate the clinical implications and outcomesof UE.The intubated adult patients with MV support in our hospital were enrolled, and they were divided into the UE and non-UE groups.Demographic data, admission unit, MV duration, overall weaning rate, and mortality rates were compared. The outcomes of UE inordinary ward and intensive care unit (ICU) were also assessed.Totally 9245 intubated adult patients were included. UE occurred in 303 (3.5%) patients, and the UE events were 0.27times/100MV days. Old age, nonoperation related MV cause, and admission out of the ICU were significant factors associated with UE events.UE patients showed a trend of better overall weaning rate (71.9% vs 66.7%, P=.054) than non-UE. However, the in-hospital mortalityrate (25.7% vs 24.8%, P=.713) were similar between the UE and non-UE patients. The reintubation rate of UE patients was 44.1%(142/322). Successful UEs were associated with patients in weaning process (52.8% vs 38.7%, P=.012), and patients received noninvasive positive pressure ventilation (NIPPV) support after UE (19.4% vs 3.5%, P