Hemodynamic monitoring in the mechanically ventilated patient

Interactions between the heart and lungs are magnified in patients undergoing mechanical ventilation and the consequences of these interactions always need to be considered when managing ventilated patients. In patients with normal lungs and normal cardiovascular function monitoring needs are minimal, but when oxygenation and cardiac function are compromised careful assessment of the consequences of changes in ventilator settings needs to be considered to ensure that adequate oxygen delivery is maintained.

Primary determinants of heart-lung interactions are first reviewed and then approaches to the use of simple hemodynamic measurements such as respiratory variations in central venous and pulmonary artery occlusion, or arterial pressure are described for assessing oxygen delivery, volume responsiveness as well as indicators of ventilatory mechanics.

Use of simple measurements available during routine monitoring can be very helpful to the informed clinician for optimizing hemodynamic performance as well as patient ventilator interactions.