January 14
by Jonathan Downham
1. Total number of breaths (RR)- These could be mandatory breaths that the ventilator will always take, or could include some spontaneous breaths that the patient has also initiated. As the patient is weaned off the ventilator they could all be breaths initiated by the patient.
2. Tidal Volume (TV)- this is a measure of the volume of each individual breath measured in millilitres. If the patient is also taking some breaths this number can vary depending on the amount of support the ventilator is giving the patient for their own efforts.
3. Minute Volume (MV)- this is the volume of all the breaths over one minute. So MV = TV X RR
4. Peak Airway Pressure- how much pressure is having to be exerted by the ventilator to achieve the tidal volumes. Ideally the lower the better. Higher pressures imply some problem with the airway or the lungs and it is believed that higher pressures are more damaging to the lungs themselves.
1. Oxygen percentage- What is the percentage of oxygen in the air we are giving the patient. This can range from 21% (same as room air) all the way up to 100%
2. PEEP- Positive End Expiratory Pressure. This is how much pressure is left in the patients lungs at the end of expiration. This helps prevent collapse of the alveoli and improve oxygenation.
3. Inspired Pressure- This is the pressure we are asking the ventilator to apply with each breath. This is only in pressure controlled ventilation. If it was volume controlled ventilation we would be setting the tidal volume per breath here.
4. Rate- The number of mandatory breaths that the ventilator will deliver.
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