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Updated: Feb 13, 2026

Normothermic Negative Pressure Ventilation Ex Situ Lung Perfusion: Evaluation of Lung Function and Metabolism
Published on: February 14, 2022
Incentive spirometry and positive expiratory pressure improve ventilation and recruitment in postoperative recovery:
Gregory Reychler1,2,3, Valeska Uribe Rodriguez4,5, Cheryl Elizabeth Hickmann4,5
1Institut de Recherche Expérimentale et Clinique (IREC), Pôle de Pneumologie, ORL & Dermatologie, Université Catholique de Louvain, Brussels, Belgium.
Abstract:
Introduction: Impairment of global and regional pulmonary ventilations is a well-known consequence of general anesthesia. Positive expiratory pressure (PEP) or incentive spirometry (IS) is commonly prescribed, albeit their efficacy is poorly demonstrated. The aim of this study was to assess the effects of PEP and IS on lung ventilation and recruitment in patients after surgery involving anesthesia using electrical impedance tomography (EIT). Method: Ten male subjects (age = 61.2 ± 16.3 years; BMI = 25.3 ± 3.8 kg/m2), free of pulmonary disease before being anesthetized, were recruited. Two series of manoeuvers (PEP and volume-oriented IS) were randomly performed with quiet breathing interposed between these phases. Pulmonary ventilation (ΔEELVVT (i - e)) and recruitment (ΔEELI) were evaluated continuously in a semi-seated position during all phases by EIT. Comparisons between rest and treatment were performed by Wilcoxon signed rank test. Rest phases were compared by a mixed ANOVA. Bonferroni method was used for post-hoc comparisons. Results: ΔEELVVT (i - e) and ΔEELI were significantly increased by both techniques (+422% [p < 0.001]; +138% [p = 0.040] and +296% [p < 0.001]; +638% [p < 0.001] for PEP and IS, respectively). No difference was observed between both manoeuvers neither on ventilation nor on recruitment. This positive effect disappeared during the quiet breathing phases. Conclusion: IS and PEP improved ventilation and recruitment instantaneously without remnant effect after stopping the exercise.
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