TY - JOUR
T1 - Experimental intra-abdominal hypertension attenuates the benefit of positive end-expiratory pressure in ventilating effusion-compressed lungs
AU - Formenti, Paolo
AU - Graf, Jeronimo
AU - Cortes, Gustavo A.
AU - Faltesek, Katherine
AU - Gard, Kenneth
AU - Adams, Alexander B.
AU - Tashjian, Joseph
AU - Dries, David J.
AU - Marini, John J.
PY - 2012/7
Y1 - 2012/7
N2 - Objective: To test the ability of positive end-expiratory pressure to offset the reduction of resting lung volume caused by intra abdominal hypertension, unilateral pleural effusion, and their combination. Design: Controlled application of intrapleural fluid, raised abdominal pressure and their combination before and after positive end-expiratory pressure in an anesthetized porcine model of controlled ventilation. Setting: Large animal laboratory of a university-affiliated hospital. Subjects: Fourteen deeply anesthetized swine (weight 30-35 kg). Interventions: Unilateral pleural effusion instillation (13 mL/kg), intra-abdominal hypertension (15 mm Hg), and simultaneous pleural effusion/intra abdominal hypertension. Measurements: Tidal compliance, end-expiratory lung aeration by gas dilution functional residual capacity, and quantitative analyses of computerized tomograms of the lungs at the extremes of the tidal cycle. MAIN Results: Positive end-expiratory pressure of 10 cm H2O (positive end-expiratory pressure10) increased mean functional residual capacity by 368 mL when pleural effusion was present and by 184 mL when intra-abdominal hypertension was present. When pleural effusion and intra-abdominal hypertension were simultaneously applied, positive end-expiratory pressure 10 failed to improve tidal compliance and increased functional residual capacity by only 77 mL, whereastidal recruitment during ventilation remained substantial. Conclusions: The presence of intra-abdominal hypertension negates most of the positive end-expiratory pressure10 benefit in reversing pleural effusion-induced de-recruitment. Relief of intra-abdominal hypertension may be instrumental to the treatment of pleural effusion-associated lung restriction and cyclical tidal collapse and reopening.
AB - Objective: To test the ability of positive end-expiratory pressure to offset the reduction of resting lung volume caused by intra abdominal hypertension, unilateral pleural effusion, and their combination. Design: Controlled application of intrapleural fluid, raised abdominal pressure and their combination before and after positive end-expiratory pressure in an anesthetized porcine model of controlled ventilation. Setting: Large animal laboratory of a university-affiliated hospital. Subjects: Fourteen deeply anesthetized swine (weight 30-35 kg). Interventions: Unilateral pleural effusion instillation (13 mL/kg), intra-abdominal hypertension (15 mm Hg), and simultaneous pleural effusion/intra abdominal hypertension. Measurements: Tidal compliance, end-expiratory lung aeration by gas dilution functional residual capacity, and quantitative analyses of computerized tomograms of the lungs at the extremes of the tidal cycle. MAIN Results: Positive end-expiratory pressure of 10 cm H2O (positive end-expiratory pressure10) increased mean functional residual capacity by 368 mL when pleural effusion was present and by 184 mL when intra-abdominal hypertension was present. When pleural effusion and intra-abdominal hypertension were simultaneously applied, positive end-expiratory pressure 10 failed to improve tidal compliance and increased functional residual capacity by only 77 mL, whereastidal recruitment during ventilation remained substantial. Conclusions: The presence of intra-abdominal hypertension negates most of the positive end-expiratory pressure10 benefit in reversing pleural effusion-induced de-recruitment. Relief of intra-abdominal hypertension may be instrumental to the treatment of pleural effusion-associated lung restriction and cyclical tidal collapse and reopening.
KW - Functional residual capacity
KW - intra abdominal hypertension
KW - mechanical ventilation
KW - pleural effusion
KW - positive end-expiratory pressure
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U2 - 10.1097/CCM.0b013e318250aa40
DO - 10.1097/CCM.0b013e318250aa40
M3 - Article
C2 - 22710205
AN - SCOPUS:84862736709
SN - 0090-3493
VL - 40
SP - 2176
EP - 2181
JO - Critical care medicine
JF - Critical care medicine
IS - 7
ER -