Comparison of three methods of measurement of pulmonary artery catheter readings in critically ill patients

BACKGROUND: Pulmonary artery catheter readings are critical for clinical decision making and therapeutic intervention in critically ill patients. Research data of digital display versus graphic strip chart recording of hemodynamic pressures during spontaneous breathing and mechanical ventilation are inconclusive. OBJECTIVES: To compare three methods of measurement of hemodynamic pressure readings from the pulmonary artery catheter in critically ill patients during mechanical ventilation and spontaneous breathing. METHODS: A nonrandomized, repeated-measures design was used to compare hemodynamic pressures (right atrial, systolic, diastolic, and wedge pressures) from the pulmonary artery catheter in cardiovascular patients during mechanical ventilation (n = 25) and again during spontaneous breathing (n = 19). RESULTS: Using repeated measures analysis of variance, statistically significant differences were noted in the pulmonary artery diastolic, wedge, and right atrial pressure during mechanical ventilation. During spontaneous breathing, significant differences occurred in pulmonary artery systolic and wedge pressures only. No statistically significant difference occurred in the systolic pressure during mechanical ventilation, or the pulmonary artery diastolic and right atrial pressures during spontaneous breathing. CONCLUSIONS: The results of this study indicate that graphic recording is the most reliable means of measuring hemodynamic pressure at end-expiration. Further research is needed to validate these findings with other models of monitoring equipment and other patient populations.