Positive end-expiratory pressure following coronary artery bypass grafting Full Text
Minerva Anestesiologica, 06/27/2012
Dongelmans DA et al. – Use of higher positive end–expiratory pressure (PEEP) levels after elective uncomplicated coronary artery bypass grafting (CABG) improves pulmonary compliance and oxygenation but seems to be associated with a delay in tracheal extubation.Methods
- Secondary retrospective analysis of 2 randomized controlled trials: in the first trial patients were weaned with PEEP levels of 10cmH2O for the first 4hours followed by PEEP levels of 5cmH2O until tracheal extubation (high PEEP, HP); and the second trial patients were weaned with PEEP levels of 5cmH2O during the entire weaning phase (low PEEP, LP).
- The primary endpoint was pulmonary compliance.
- Secondary endpoints included arterial oxygenation, duration of mechanical ventilation and postoperative pulmonary complications.
- The analysis included 121 patients; 60 HP patients and 61 LP patients.
- Baseline characteristics were similar.
- Compared to LP patients, HP patients had a better pulmonary compliance, 47.2&plusmmn;14.1 versus 42.7±10.2ml/cmH2O (P<0.05), and higher levels of PaO2, 18.5±6.6 (138.75±49.5) versus 16.7±5.4 (125.25±40.5)kPa (mmHg) (P<0.05).
- Patients in the HP group were less frequent in need of supplementary oxygen after ICU discharge.
- These differences remained present during the entire weaning phase, even after reduction of PEEP.
- However, HP patients had a longer time till tracheal extubation, 16.9±6.1 versus 10.5±5.0hours (P<0.001).
- HP patients had longer durations of postoperative infusion of propofol, 4.9 (2.6–7.4) versus 3.5 (1.8–5.8)hours (P<0.05).
- There were no differences in use of inotropes.
- Cummulative fluid balances were sligthly higher in HP patients.