• Massimo Zambon, Paolo Beccaria, Jun Matsuno, Marco Gemma, Elena Frati, Sergio Colombo, Luca Cabrini, Giovanni Landoni, and Alberto Zangrillo.
• 1Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientific Institute, Milan, Italy. 2Vita-Salute San Raffaele University, Milan, Italy.
• Crit. Care Med. 2016 Jul 1; 44 (7): 1347-52.

ObjectiveMechanical ventilation contributes to diaphragmatic atrophy and dysfunction, and few techniques exist to assess diaphragmatic function: the purpose of this study was to quantify diaphragm atrophy in a population of critically ill mechanically ventilated patients with ultrasound and to identify risk factors that can worsen diaphragmatic activity.DesignProspective observational study.SettingICU of a 1,200-bed university hospital.PatientsNewly intubated adult critically ill patients.InterventionsDiaphragm thickness in the zone of apposition was measured daily with ultrasound, from the first day of mechanical ventilation till discharge to the main ward.Measurements And Main ResultsDaily atrophy rate (ΔTdi/d) was calculated as the reduction in percentage from the previous measurement. To analyze the difference in atrophy rate (ΔTdi/d), ventilation was categorized into four classes: spontaneous breathing or continuous positive airway pressure; pressure support ventilation 5-12 cm H2O (low pressure support ventilation); pressure support ventilation greater than 12 cm H2O (high pressure support ventilation); and controlled mechanical ventilation. Multivariate analysis with ventilation support and other clinical variables was performed to identify risk factors for atrophy. Forty patients underwent a total of 153 ultrasonographic evaluations. Mean (SD) ΔTdi/d was -7.5% (12.3) during controlled mechanical ventilation, -5.3% (12.9) at high pressure support ventilation, -1.5% (10.9) at low pressure support ventilation, +2.3% (9.5) during spontaneous breathing or continuous positive airway pressure. At multivariate analysis, only the ventilation support was predictive of diaphragm atrophy rate. Pressure support predicted diaphragm thickness with coefficient -0.006 (95% CI, -0.010 to -0.002; p = 0.006).ConclusionsIn critically ill mechanically ventilated patients, there is a linear relationship between ventilator support and diaphragmatic atrophy rate.

20 keywords...

hide…