Anesthesia & Clinical Research
Open Access

Abstract

Determination of Optimal PEEP by Carbon Dioxide Production (VCO₂) in ARDS Patients

Mohamed Samir Abdelghafar and Zahretelwady Mohamed Salaheldin Mohamed

Background: The use of PEEP is a corner stone in the management of ARDS. Several methods were investigated to determine the optimal PEEP. However, no method is considered gold standard. The study investigated whether the use of VCO₂ to determine optimal PEEP value in ARDS patients improves oxygenation, alveolar ventilation and static compliance compared to ARDSNet FiO₂-PEEP combination.
Patients and methods: This prospective randomized controlled study was conducted at a tertiary university hospital ICU including sixty mechanically ventilated ARDS patients. Patients were randomized between two groups; group A, where PEEP was titrated using FiO₂-PEEP combination and group B, where PEEP was titrated according to VCO₂. In this group, PEEP was increased in increments of 2 cm H₂O every 20 minutes with VCO₂ monitoring. Once it failed to recover to baseline, the preceding PEEP value was considered optimum.
Results: Group B received statistically significant higher values of PEEP 10.87 (± 2.35) vs. 9.20 (± 1.13) cm H₂O; p <0.001 and lower values of FiO₂ 40 (± 0) vs. 57.00 (± 8.37) %; p <0.001, compared with group A. Significantly higher PaO₂/FiO₂ and static compliance were observed in group B compared with group A [216.27 (± 36.79) vs. 158.60 (± 42.65); p <0.001 and 57.80 (± 7.93) vs. 52.73 (± 4.98) mL/cm H₂O; p <0.04, respectively] with no associated impact of both interventions on VCO₂ or MAP.
Conclusion: Optimum PEEP determination using VCO₂ revssulted in improvement of oxygenation and lung compliance compared with FiO₂-PEEP combination in ARDS patients. Higher PEEP used was not associated with increase in complications.