Abstract
Objective
To test a method that allows automatic set-up of the ventilator controls at the onset of ventilation.
Design
Prospective randomized crossover study.
Setting
ICUs in one adult and one children's hospital in Switzerland.
Patients
Thirty intubated stable, critically ill patients (20 adults and 10 children).
Interventions
The patients were ventilated during two 20-min periods using a modified Hamilton AMADEUS ventilator. During the control period the ventilator settings were chosen immediately prior to the study. During the other period individual settings were automatically determined by the ventilator (AutoInit).
Measurements and results
Pressure, flow, and instantaneous CO2 concentration were measured at the airway opening. From these measurements, series dead space (V DS), expiratory time constant (RC), tidal volume (V T), total respiratory frequency (f tot), minute ventilation (MV), and maximal and mean airway pressure (P aw, max andP aw, mean) were calculated. Arterial blood gases were analyzed at the end of each period.P aw, max was significantly less with the AutoInit ventilator settings whilef tot was significantly greater (P<0.05). The other values were not statistically significant.
Conclusions
The AutoInit ventilator settings, which were automatically derived, were acceptable for all patients for a period of 20 min and were not found to be inferior to the control ventilator settings. This makes the AutoInit method potentially useful as an automatic startup procedure for mechanical ventilation.
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Laubscher, T.P., Frutiger, A., Fanconi, S. et al. The automatic selection of ventilation parameters during the initial phase of mechanical ventilation. Intensive Care Med 22, 199–207 (1996). https://doi.org/10.1007/BF01712237
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DOI: https://doi.org/10.1007/BF01712237