Mechanical Ventilation

Mechanical ventilation is used in the emergency setting in response to a respiratory crisis. This chapter focuses on the use of the computerized ventilator since it provides better control over ventilatory variables including oxygen level, humidity, tidal volume, and inspiratory pressure, than a manually operated ventilator. Pressure limited ventilation means that the ventilator will deliver air to a preset inspiratory pressure regardless of the volume that is given. Since there is a tendency for decreased lung compliance with this type of ventilation, PaCO2 and tidal volume are closely monitored. Many different drugs and protocols have been used to sedate an animal for mechanical ventilation. Mechanical ventilation is not risk free. The two primary problems encountered with mechanical ventilation include barotrauma and infection. Ventilator patients are often immunosup-pressed which also increases their risk of infection. The clinician managing a patient on the ventilator also has the choice of type of airway.