Background:The application of mechanical ventilation for critically ill patients is a
life-support system that can maintain their adequate lung function. Positive end-expiratory
pressure is a significant adjunct mode for mechanically ventilated patients. Historically, it
is ordinarily applied for mechanically ventilated patients to improve oxygenation and
alveolar ventilation and reduce alveolar atelectasis and ventilation/perfusion mismatch.
Although several international studies revealed the extensive positive effects of high
positive end-expiratory pressure (≥ 10 cmH2O) for critically ill patients with or without
lung disorders, low levels of positive end-expiratory pressure (3 to 5 cmH2O) are regularly
used for mechanically ventilated patients.Aim: The current study aimed to investigate the
effect of different values of positive end-expiratory pressure on ventilation parameters
among critically ill patients. Method:A quasi-experimental research design was utilized in
the current study involving a convenience sample of 164 adult mechanically ventilated
patients. Data were collected using a critically ill patient's ventilation parameters
assessment tool. Results:The current study revealed that the modification of positive endexpiratory
pressure values from moderate (6-8 cmH2O) to high (8-10 cmH2O) improved
patients' ventilatory parameters. More investigations are required to support the evidence
of using this approach when caring for mechanically ventilated patients.