An alternative method for coordinating pulmonary capillary wedge pressure measurements with the respiratory cycle

Changes in intrathoracic pressure during the respiratory cycle cause variations in pulmonary vascular pressures. This affects pulmonary hemodynamic measurements in critically ill patients, particularly those receiving mechanical ventilation. With certain newer ventilators, the machine-pressure and/or expiratory-flow signal can be graphed simultaneously with hemodynamic pressure. The end-expiratory point determined from these graphs can be used to identify the corresponding wedge pressure on the hemodynamic tracing.