Dilated aortic root influences pulmonary artery catheter placement in anesthetized patients.

Purpose: The placement of a pulmonary artery catheter sometimes needs long time by observing the pressure wave, and several factors have been reported to hinder the placement. In the present study, we examined whether enlargement of the aortic root is associated with longer time for the placement.

Method: We examined the time required for the catheter placement. The catheter placement time was defined as the duration of time required for the catheter to float from the CVP position to the pulmonary artery. The catheter placement was performed by one experienced physician. We examined the following factors on the catheter placement time: the patient's age, height, weight, cardiothoracic ratio, tricuspid regurgitation, ejection fraction and the diameter of aortic annulus, sinus of Valsalva, sinotubular junction, and proximal ascending aorta. These diameter values were divided by body surface area (BSA) to equalize among different physical sizes. The data were analyzed by multiple linear regression analysis after univariate analysis.

Results: The univariate analysis showed that ejection fraction and aortic annulus/BSA, sinus of Valsalva/BSA, and sinotubular junction/BSA correlated with the catheter placement time ( P  = 0.079, 0.030, 0.029, and 0.025, respectively). Since the three aortic root values correlated with each other, we chose the sinotubular junction/BSA for the following multivariate analysis, because of the highest P value. The multivariate analysis showed that sinotubular junction/BSA had a significant positive association with the placement time ( P  = 0.048).

Conclusion: The present study showed that enlargement of the aortic root is associated with long placement time of the catheter.