Usefulness of the maximum rate of pressure rise in the central and peripheral arteries after weaning from cardiopulmonary bypass in pediatric congenital heart surgery

Abstract

The maximum rate of pressure rise (dP/dtmax) in radial artery has been proposed as a noninvasive surrogate of aortic dp/dtmax, reflecting left ventricular (LV) contractility in children. The aim of this study was to investigate relationship between aortic and radial dp/dtmax at weaning from cardiopulmonary bypass (CPB) and usefulness of these indices for estimating postoperative outcomes in pediatric congenital heart surgery.Aortic and radial arterial pressure waveforms were analyzed simultaneously during weaning from CPB in 29 congenital heart surgery. The maximum first derivatives of aortic and radial arterial waveforms were calculated and averaged from 3 consecutive respiratory cycles. We obtained the maximum vasoactive inotropic score during the first 36 postoperative hours, LV ejection fraction, and fractional shortening on transthoracic echocardiography performed within postoperative day 7.A significant difference between aortic and radial dP/dtmax was observed (mean difference 356 mm Hg/s, 44% of averages), and radial dP/dtmax was weakly correlated with aortic dP/dtmax (r =0.373, P = 0.047). Aortic dP/dtmax was significantly associated with the maximum vasoactive inotropic score (P < 0.001), postoperative LV ejection fraction (P = 0.018), and fractional shortening (P = 0.015); however, radial dP/dtmax was not. On Receiver operating characteristic analysis, aortic dP/dtmax had a greater area under the curve than radial dP/dtmax in predicting higher vasoactive inotropic score (0.827 vs 0.673).Immediately after CPB in pediatric congenital heart surgery, radial dP/dtmax may not replace aortic dP/dtmax because of a discrepancy between central and peripheral arterial waveforms. In this critical period, aortic dP/dtmax can be useful to estimate postoperative ventricular function rather than peripherally derived dP/dtmax.

Influence of changes in ventricular systolic function and loading conditions on pulse contour analysis-derived femoral dP/dtmax

“…Our study challenges the previous belief that femoral d P /d t max could be used as a reliable marker of LV systolic function at the bedside. This belief was based on the observed good correlation between LV and arterial d P /d t max during periods of haemodynamic stability [7, 9, 12]. However, correlations alone lack the sufficient value to inform on the responses of femoral d P /d t max to treatments during cardiovascular failure.…”

“…Several studies have suggested that measurements of arterial d P /d t max obtained from radial [7, 9] and femoral [7, 10] arterial pressure waveforms were comparable to LV d P /d t max and, in some cases, might be useful for predicting patient outcome [11]. However, conflicting results regarding the comparability of LV d P /d t max and arterial d P /d t max have also been presented in both adults and children [12, 13]. Despite these uncertainties, arterial d P /d t max is most often presented as a marker of LV systolic function in many off-the-shelf haemodynamic monitoring systems.…”

“…Despite these uncertainties, arterial d P /d t max is most often presented as a marker of LV systolic function in many off-the-shelf haemodynamic monitoring systems. Supportive literature is based on the observed good correlation between LV and arterial d P /d t max during periods of haemodynamic stability [7–9, 12]. However, these good correlations documented on stable patients do not necessarily imply that femoral d P /d t max provides an adequate evaluation of changes in LV systolic function during haemodynamic challenges.…”

Continual measurement of arterial dP/dtmax enables minimally invasive monitoring of left ventricular contractility in patients with acute heart failure

“…In contrast, Kim et al [19] studied the relationship between arterial dP/dt max from the radial artery, aortic dP/dt max , and selected echocardiographic variables such as LV ejection fraction or LV fractional shortening in children undergoing congenital heart disease surgery. They did not find a significant correlation between arterial dP/dt max and the other variables, and these observations were explained by differences between radial artery and aortic pressure waveforms.…”

Can we trust radial artery pressure monitoring for cardiac surgery?

“…(B) To detect or suspect an RFAPG, several methods can be used, including radial AP waveform analysis, the use of NIBP of the upper extremity,23,39 and ultrasound techniques using two-dimensional measurement and Doppler. Unreliable radial arterial pressure should be suspected if two-dimensional ultrasound measurement of the radial artery diameter is less than 1.8 mm, 10 if the change of pressure over time (dP/dt) of the radial artery does not correlate with cardiac function,6,42 if the estimated dP/dt and the PG calculated from the MR Doppler signal is higher than the radial artery pressure18,43 or if there is no triphasic arterial signal using Doppler interrogation of a radial or brachial artery. Dynamic testing and evaluation of damping coefficient should also always be performed when using an arterial pressure signal 44.…”