Anestéziológia a intenzívna medicína 1/2012

Influence of PEEP and early recruitment maneuver in operations with cardiopulmonary by-pass (CPB)

Type of Study: Prospective, randomised. Goal: The goal of this research was to prove that intermediate-high „preventative PEEP“ (8 cm H2O) combined with early recruitment maneuver (RM) (PEEP up-to 20 cm H2O) can improve impaired lung-functions when compared to low-PEEP (3 cm H2O), and along with protective perioperative lung ventilation, they can improve gas transport, lung-mechanics as well as patient’s adaptation to spontaneous brething. Material and Methods: 40 patients undergoing coronary artery by-pass grafting (CABG) in cardiopulmonary by-pass (CPB) were randomly chosen and divided in two groups. Group 1 was created by patients in whom perioperative and post-operative PEEP of 3±1 cm H2O was applied while PEEP 8±1 cm H2O applied in group 2. The sub-groups of the two main groups were created by half of the patients in which an early recruitment maneuver (RM) with PEEP up to 20 cm H2O was applied. Results: a-ADO2 markedly increased after discontinuation of ECC and the difference between groups 1 and 2 is statistically significant even after ICU admission (p‹0.01). PaO2/FiO2 index (mm Hg) has decreased in both groups under 300 mm Hg after CPB discontinuation. The oxigenation index rose over 300 mmHg in group 2 after admission to ICU in both subgroups with or without earlz RM (p‹0.05). Lung-compliance (Cdyn /mlcm-1) was post operatively markedly higher in group 2 and specially in subgroup where early RM was applied. The results were statistically significantly different (p‹0.01) after RM application aproximately 30-60 min. after ICU admission. There were no significant cardiovascular changes found even when higher PEEP or RM applied. Adaptation to spontaneous breathing, assessed by its frequency after extubation was better in group 2. Conclusion: Based on the above-mentioned results the authors state that the intermediate-high (1 cm H2O10 kg-1) PEEP and repeated early RM can be beneficial in prevention of lung atelectasis, it can improve oxigenation and improve lung-mechanics as well as improve adaptation for spontaneous brething after discontinuation of ALV without substantial adverse cardiovascular influences.

Keywords: ALV, PEEP, reacruitment manever (RM), ECC.