The outcome of mechanically ventilated patients initially denied admission to an intensive care unit (ICU) and subsequently admitted is unclear. We compared outcomes of patients denied ICU admission and subsequently admitted, to those of patients admitted to the ICU and to patients refused ICU admission. The medical records of all the patients who were subjected to mechanical ventilation for at least 24h over a 4year period (2010–2014) were reviewed. Of 707 patients (757 admissions), 124 (18%) were initially denied ICU admission and subsequently admitted.