[LS2] New developments in mechanical ventilation care
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同時通訳付き】
Consistent evidence has accumulated, demonstrating that Driving Pressure (ΔP) is the key variable linking ventilation strategy to death. Subjects who had lower ΔPs are relatively protected, even when exposed to tidal-volumes or plateau-pressures considered unsafe. Conversely, those exposed to higher ΔPs are systematically unprotected, independently of other ventilatory variables.
ARDS patients commonly present a large inter-individual variability in respiratory-system compliance, to the extent that tidal-volume, if simply scaled to PBW, becomes a poor predictor of ∆P (explaining 14% of its variance, only). Consequently, tidal-volume is a poor predictor of survival or barotrauma.
Evidence has also accumulated, suggesting that respiratory-rate is another independent parameter that should be directly controlled. We will demonstrate that, by simply focusing on two bedside parameters (driving pressures and respiratory rate), the full benefits of lung protection is obtained. More integrative parameters like mechanical power do not add any relevant information, introducing unnecessary complexity. Dead-space estimates help to choose the optimized combination of driving-pressures and respiratory rate for an individual patient.
After the first 48-72 hours of controlled mechanical ventilation, the promotion of spontaneous efforts is an important strategy to avoid muscle atrophy. By using imaging technologies like EIT, however, we have shown that the combined presence of persisting lung disease, high respiratory drive, and strong diaphragmatic contraction may be disastrous during this assisted phase of mechanical ventilation. In the presence of too strong efforts, the use of conventional protective strategy does not work. Despite an apparently low tidal-volume, marked overstretch of dependent lung regions is common: frequently generating extreme lung deformations, with regional tidal volumes > 15 mL/kg, and equivalent driving-pressures > 20 cmH2O. Novel technics like partial paralysis, phrenic blockage and bedside detectors (with artificial intelligence) to detect dysynchrony are promising tools to promote better patient-ventilator synchrony and to optimize lung protection. We will propose novel technologies and practical tips to estimate “muscle-driving-pressure” at the bedside, and also to detect excessive muscle effort, helping clinicians to keep it within safe limits. Illustrative cases in the pediatric and neonatology field will be also discussed. A dual target during mechanical ventilation will be possible in the next years: lung protection in conjunction with diaphragmatic protection.
ARDS patients commonly present a large inter-individual variability in respiratory-system compliance, to the extent that tidal-volume, if simply scaled to PBW, becomes a poor predictor of ∆P (explaining 14% of its variance, only). Consequently, tidal-volume is a poor predictor of survival or barotrauma.
Evidence has also accumulated, suggesting that respiratory-rate is another independent parameter that should be directly controlled. We will demonstrate that, by simply focusing on two bedside parameters (driving pressures and respiratory rate), the full benefits of lung protection is obtained. More integrative parameters like mechanical power do not add any relevant information, introducing unnecessary complexity. Dead-space estimates help to choose the optimized combination of driving-pressures and respiratory rate for an individual patient.
After the first 48-72 hours of controlled mechanical ventilation, the promotion of spontaneous efforts is an important strategy to avoid muscle atrophy. By using imaging technologies like EIT, however, we have shown that the combined presence of persisting lung disease, high respiratory drive, and strong diaphragmatic contraction may be disastrous during this assisted phase of mechanical ventilation. In the presence of too strong efforts, the use of conventional protective strategy does not work. Despite an apparently low tidal-volume, marked overstretch of dependent lung regions is common: frequently generating extreme lung deformations, with regional tidal volumes > 15 mL/kg, and equivalent driving-pressures > 20 cmH2O. Novel technics like partial paralysis, phrenic blockage and bedside detectors (with artificial intelligence) to detect dysynchrony are promising tools to promote better patient-ventilator synchrony and to optimize lung protection. We will propose novel technologies and practical tips to estimate “muscle-driving-pressure” at the bedside, and also to detect excessive muscle effort, helping clinicians to keep it within safe limits. Illustrative cases in the pediatric and neonatology field will be also discussed. A dual target during mechanical ventilation will be possible in the next years: lung protection in conjunction with diaphragmatic protection.