Arterial Diameter Variations as a New Index for Stroke Volume Assessment: An Experimental Study on a Controlled Hemorrhagic Shock Model in Piglets

Abstract

Background: The assessment of cardiac output (CO) is a major challenge during shock. The criterion standard for CO evaluation is transpulmonary thermodilution, which is an invasive technique. Speckle tracking is an automatized method of analyzing tissue motion using echography. This tool can be used to monitor pulsed arterial diameter variations with low interobserver variability. An experimental model of controlled hemorrhagic shock allows for multiple CO variations. The main aim of this study is to show the correlation between the femoral arterial diameter variations (fADVs) and the stroke volume (SV) measured by thermodilution during hemorrhagic shock management and the resuscitation of anesthetized piglets. The secondary objective is to explore the respective correlations between SV and subaortic time-velocity index, abdominal aorta ADV, carotid ADV, and subclavian ADV. Methods: Piglets were bled until mean arterial pressure reached 40 mm Hg. Controlled hemorrhage was maintained for 30 minutes before randomizing the piglets to three resuscitation groups—the fluid-filling group (reanimated with saline solution only), NEph group (norepinephrine + saline solution), and Eph group (epinephrin + saline solution). Speckle tracking, echocardiographic, and hemodynamic measures were performed at different stages of the protocol. Results: Thirteen piglets were recruited and included for statistical analysis. Of all the piglets, 164 fADV measures were attempted and 160 were successful (98%). The correlation coefficient between fADV and SV was 0.71 (95% confidence interval [CI], 0.62 to 0.78; P < 0.01). The correlation coefficient between SV and abdominal aorta ADV, subclavian ADV, and carotid ADV was 0.30 (95% CI, 0.13 to 0.46; P < 0.01), 0.56 (95% CI, 0.45 to 0.66, P < 0.01), and 0.15 (95% CI, −0.01 to 0.30, P = 0.06), respectively. Conclusions: In this hemorrhagic shock model using piglets, fADV was strongly correlated with SV.

Unveiling the Significance of Dynamic Arterial Elastance: An Insightful Approach to Assessing Arterial Load in an Endotoxin Shock Model

“…settings, decreases Cart and increases the pulsatile component of the arterial load (24). Furthermore, in a study conducted by Guinot et al, it was demonstrated that the utilization of a hemodynamic algorithm incorporating dynamic arterial Ea led to a shorter duration of norepinephrine treatment and reduced ICU stay for patients experiencing vasoplegic syndrome after cardiac surgery (25).…”

“…Its performance was found to be poor in patients undergoing surgical procedures but good in critical care patients, which can be explained by the relationship between EaDyn and Cart. The use of norepinephrine, which is common in critical care settings, decreases Cart and increases the pulsatile component of the arterial load (24). Furthermore, in a study conducted by Guinot et al , it was demonstrated that the utilization of a hemodynamic algorithm incorporating dynamic arterial Ea led to a shorter duration of norepinephrine treatment and reduced ICU stay for patients experiencing vasoplegic syndrome after cardiac surgery (25).…”