Positive end-expiratory pressure adjusted for intra-abdominal pressure – A pilot study☆
Intra-abdominal hypertension (IAH) is associated with impaired respiratory function. Animal data suggest that positive end-expiratory pressure (PEEP) levels adjusted to intra-abdominal pressure (IAP) levels may counteract IAH-induced respiratory dysfunction.Purpose:
In this pilot study, our aim was to assess whether PEEP adjusted for IAP can be applied safely in patients with IAH.Materials and methods:
We included patients on mechanical ventilation and with IAH. Patients were excluded with severe cardiovascular dysfunction or severe hypoxemia or if the patient was in imminent danger of dying. Following a recruitment manoeuvre, the following PEEP levels were randomly applied: PEEP of 5 cmH2O (baseline), PEEP = 50% of IAP, and PEEP = 100% of IAP. After a 30 min equilibration period we measured arterial blood gases and cardio-respiratory parameters.Results:
Fifteen patients were enrolled. Six (41%) patients did not tolerate PEEP = 100% IAP due to hypoxemia, hypotension or endotracheal cuff leak. PaO2/FiO2 ratios were 234 (68), 271 (99), and 329 (107) respectively. The differences were significant (p = 0.009) only between baseline and PEEP = 100% IAP.Conclusions:
PEEP = 100% of IAP was not well-tolerated and only marginally improved oxygenation in ventilated patients with IAH.