Ventilation
PaCO2 is inversely related to the minute volume ventilation (minute volume
ventilation equals RR x Vt); therefore changes on the RR or on the Vt will affect the
PaCO2 in the opposite direction.
Is it really that simple?
Increasing PEEP can increase dead space, and decrease cardiac output.
Increasing the respiratory rate can lead to dynamic hyperinflation (aka auto-PEEP)
because of not having enough exhalation time, resulting in worsening oxygenation
and ventilation.
E. Troubleshooting
- Is it working?
Look at the patient - Listen to the patient !!
Look at the data: Pulse Ox, ABG, ETCO 2 , Chest X ray
Look at the vent (PIP; expired Vt; alarms etc) - When in doubt
DISCONNECT THE PATIENT FROM THE VENTILATOR, and begin bag
ventilation. Ensure you are bagging with 100% O2. This eliminates the ventilator
circuit as the source of the problem. Bagging by hand can also help you gauge the
patient’s compliance.
Airway first: is the tube still in? Is it patent? Is it in the right position?
Breathing next: is the chest rising? Breath sounds present and equal? Changes in