Jose Dianti1,2, John Matelski3, Manuel Tisminetzky1,2, Allan J Walkey4, Laveena Munshi1,2, Lorenzo Del Sorbo1,2, Eddy Fan1,2, Eduardo Lv Costa5, Carol L Hodgson6, Laurent Brochard1,7, Ewan C Goligher8,2. 1. Interdepartmenal Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada. 2. Department of Medicine, Division of Respirology, University Health Network, Toronto, Ontario, Canada. 3. Biostatistics Research Unit, University Health Network, Toronto, Ontario, Canada. 4. Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts. 5. Research and Education Institute, Hospital Sírio-Libanês, São Paulo, Brazil. 6. Australian and New Zealand Intensive Care-Research Centre, Monash University, Melbourne, Australia. 7. Li Ka Shing Knowledge Institute, Keenan Research Centre, St Michael's Hospital, Toronto, Ontario, Canada. 8. Interdepartmenal Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada. ewan.goligher@uhn.ca.
Abstract
BACKGROUND: The unifying goal of lung-protective ventilation strategies in ARDS is to minimize the strain and stress applied by mechanical ventilation to the lung to reduce ventilator-induced lung injury (VILI). The relative contributions of the magnitude and frequency of mechanical stress and the end-expiratory pressure to the development of VILI is unknown. Consequently, it is uncertain whether the risk of VILI is best quantified in terms of tidal volume (VT), driving pressure (ΔP), or mechanical power. METHODS: The correlation between differences in VT, ΔP, and mechanical power and the magnitude of mortality benefit in trials of lung-protective ventilation strategies in adult subjects with ARDS was assessed by meta-regression. Modified mechanical power was computed including PEEP (Powerelastic), excluding PEEP (Powerdynamic), and using ΔP (Powerdriving). The primary analysis incorporated all included trials. A secondary subgroup analysis was restricted to trials of lower versus higher PEEP strategies. RESULTS: We included 9 trials involving 4,731 subjects in the analysis. Odds ratios for moderation derived from meta-regression showed that variations in VT, ΔP, and Powerdynamic were associated with increased mortality with odds ratios of 1.24 (95% CI 1.03-1.49), 1.31 (95% CI 1.03-1.66), and 1.37 (95% CI 1.05-1.78), respectively. In trials comparing higher versus lower PEEP strategies, Powerelastic was increased in the higher PEEP arm (24 ± 1.7 vs 20 ± 1.5 J/min, respectively), whereas the other parameters were not affected on average by a higher PEEP ventilation strategy. CONCLUSIONS: In trials of lung-protective ventilation strategies, VT, ΔP, Powerelastic, Powerdynamic, and Powerdriving exhibited similar moderation of treatment effect on mortality. In this study, modified mechanical power did not add important information on the risk of death from VILI in comparison to VT or ΔP.
BACKGROUND: The unifying goal of lung-protective ventilation strategies in ARDS is to minimize the strain and stress applied by mechanical ventilation to the lung to reduce ventilator-induced lung injury (VILI). The relative contributions of the magnitude and frequency of mechanical stress and the end-expiratory pressure to the development of VILI is unknown. Consequently, it is uncertain whether the risk of VILI is best quantified in terms of tidal volume (VT), driving pressure (ΔP), or mechanical power. METHODS: The correlation between differences in VT, ΔP, and mechanical power and the magnitude of mortality benefit in trials of lung-protective ventilation strategies in adult subjects with ARDS was assessed by meta-regression. Modified mechanical power was computed including PEEP (Powerelastic), excluding PEEP (Powerdynamic), and using ΔP (Powerdriving). The primary analysis incorporated all included trials. A secondary subgroup analysis was restricted to trials of lower versus higher PEEP strategies. RESULTS: We included 9 trials involving 4,731 subjects in the analysis. Odds ratios for moderation derived from meta-regression showed that variations in VT, ΔP, and Powerdynamic were associated with increased mortality with odds ratios of 1.24 (95% CI 1.03-1.49), 1.31 (95% CI 1.03-1.66), and 1.37 (95% CI 1.05-1.78), respectively. In trials comparing higher versus lower PEEP strategies, Powerelastic was increased in the higher PEEP arm (24 ± 1.7 vs 20 ± 1.5 J/min, respectively), whereas the other parameters were not affected on average by a higher PEEP ventilation strategy. CONCLUSIONS: In trials of lung-protective ventilation strategies, VT, ΔP, Powerelastic, Powerdynamic, and Powerdriving exhibited similar moderation of treatment effect on mortality. In this study, modified mechanical power did not add important information on the risk of death from VILI in comparison to VT or ΔP.
Authors: Álvaro Mingote; Ramsés Marrero García; Martín Santos González; Raquel Castejón; Clara Salas Antón; Juan Antonio Vargas Nuñez; Javier García-Fernández Journal: Crit Care Date: 2022-10-18 Impact factor: 19.334
Authors: Francesco Zadek; Jonah Rubin; Luigi Grassi; Daniel Van Den Kroonenberg; Grant Larson; Martin Capriles; Roberta De Santis Santiago; Gaetano Florio; David A Imber; Edward A Bittner; Kathryn A Hibbert; Alex Legassey; Jeliene LaRocque; Gaston Cudemus-Deseda; Aranya Bagchi; Jerome Crowley; Kenneth Shelton; Robert Kacmarek; Lorenzo Berra Journal: Crit Care Explor Date: 2021-06-29