Effects of experimental hypovolemia and pain on pre‐ejection period and pulse transit time in healthy volunteers

Abstract

Trauma patients may suffer significant blood loss, and noninvasive methods to diagnose hypovolemia in these patients are needed. Physiologic effects of hypovolemia, aiming to maintain blood pressure, are largely mediated by increased sympathetic nervous activity. Trauma patients may however experience pain,

Agreement between Electrical Cardiometry and Pulmonary Artery Thermodilution for Measuring Cardiac Output in Isoflurane-Anesthetized Dogs

“…With blood transfusion and a colloid bolus, these changes are reversed, and the values normalize toward baseline. These results are consistent with a few human studies [ 51 , 52 , 53 ]. The PEP and LVET provide time-based assessments of the ventricular performance and to some degree depend on the heart rate or width of the QRS complex.…”

“…The LVET interval is the time from the aortic valve opening to closing (mechanical systole), denoting the aortic flow’s duration. Both these parameters represent a fine balance between the intrinsic contractile function, left ventricular preload, and afterload, but the PEP is also influenced by electrical activation [ 51 , 52 , 53 ]. The STR is a ratio of the electrical and mechanical systoles and is calculated as PEP/LVET.…”

“…The STR is a ratio of the electrical and mechanical systoles and is calculated as PEP/LVET. When ventricular systolic function is impaired and the ejection fraction is lowered, the time to generate sufficient pressure that can open the aortic valve increases while the ejection period reduces, thus resulting in higher STR values [ 51 , 52 , 53 ]. In this study, the ICON TM and VIC values are significantly decreased during hypovolemia in the anesthetized dogs as expected due to the diminished ventricular preload.…”