Effect of ventilation on the accuracy of pulmonary artery and wedge pressure measurements
A comparison was made of automated versus manual measurement of pulmonary artery (PA) and wedge (WP) pressures. The manual pressure measurements were taken at end-expiration whereas the automated measurements were taken using existing monitor and computer algorithms. A total of 40 critical care patients were divided into groups according to the ventilatory mode used (spontaneous, intermittent mandatory ventilation |IMV], or assist/control). In patients who were breathing spontaneously, the automated method underestimated mean PA pressure (MPAP) (p < 0.01), WP (p < 0.001), and PA diastolic (p < 0.001) pressure but not PA systolic pressure. In patients on IMV, the automated method underestimated MPAP (p < 0.05), WP (p < 0.001), and PA diastolic (p < 0.001) pressure and overestimated PA systolic pressure (p < 0.05). In patients on assist/control, the automated method overestimated WP (p < 0.001) and PA systolic (p < 0.005) pressure, underestimated PA diastolic (p < 0.001) pressure and did not affect MPAP. The error was not affected by respiratory rate, thoracic compliance, or level of PEEP.
Wolters Kluwer (LWW)
Critical Care Medicine
Cengiz, M., Crapo, R. O., & Gardner, R. M. (1983). Effect of ventilation on the accuracy of pulmonary artery and wedge pressure measurements. Critical Care Medicine, 11(7), 502-7.