Method for ventilation
The disclosure describes a method for automatically initiating ventilation, controlling ventilation, transitioning a ventilator to subject controlled ventilation, and weaning a subject from ventilation. The disclosure describes that the method for automatically initiating ventilation includes inputting a physical characteristic of the subject into a ventilator. The physical characteristic may be ideal body weight, height, or age. Based on the inputted physical characteristic, one or more ventilation parameters are calculated. The disclosure describes initiating ventilation based on the calculated parameters. During ventilation at least one physiological parameter of the subject is monitored. At least one ventilation parameter may be adjusted based on the monitoring of the physiological parameters and the inputted physical characteristic.
1. A method of automatically weaning a subject from a ventilator in volume support mode, comprising:
measuring at least one of end tidal exhaled carbon dioxide concentration (E T CO 2 ), volume size of breath delivered to the subject (V T ) and breath frequency;
comparing at least one of measured E T CO 2 , V T and breath frequency with predetermined E T CO 2 , V T and breath frequency target ranges based on monitoring of subject parameters and an inputted ideal body weight (IBW) to determine if the subject is ready for weaning; and
if one or more of the measured E T CO 2 , V T and breath frequency are within their respective target ranges for a predetermined period of time, determining that the subject is ready for weaning and then transitioning the ventilator from the volume support ventilation to pressure support ventilation to begin weaning.
2. The method of claim 1 , wherein an initial pressure utilized in the pressure support ventilation is adjusted at a preset value below a target pressure utilized in said volume support ventilation.
3. The method of claim 2 , further comprising reducing said initial pressure in a step wise manner over predetermined time intervals.
4. The method of claim 3 , wherein said initial pressure is reduced by about 2 hPa over time intervals of about 15 minutes.
5. The method of claim 3 , further comprising initiating a spontaneous breath trial.
6. The method of claim 5 , wherein the subject maintains at least one physiological parameter at an acceptance criteria for a defined period of time during the spontaneous breath trial.
7. The method of claim 6 , further comprising providing an alert that the subject can be withdrawn from mechanical ventilation.
8. The method of claim 5 , further comprising adjusting ventilation parameters back to the volume support ventilation when the subject does not maintain at least one physiological parameter at an acceptable level for a defined period of time during the spontaneous breath trial.