The need for ventilatory support is one of the commonest indications for admission into the intensive care unit (ICU). Despite the usefulness of mechanical ventilation, its damaging effect on the lungs has also been widely recognized.The study was a prospective, case-controlled survey of all mechanically ventilated patients admitted in our ICU from November 2013 to April 2014. For every ventilated patient, a non-ventilated similar patient served as a control.A total of 128 patients were admitted into the ICU over the six month period and 44 patients constituting 34.4% were mechanically ventilated. The average duration of mechanical ventilation was 12.30 ± 10.10 days. Duration of mechanical ventilation, use of arterial blood gas measurement and ionotropic support had significant effect on weaning from ventilation with p values of 0.005, 0.05 and <0.001 respectively. Mechanically ventilated patients had >4 times chance of death than non-ventilated patients.Mechanical ventilation though a useful therapeutic intervention in the ICU is associated with increased mortality. Duration of ventilation, use of arterial blood gas (ABG) and need for ionotropic support influenced successful weaning off ventilator. It may be expedient therefore to weigh the risk: benefit assessment of mechanical ventilation before commencement in the ICU.