Effect of systemic vascular resistance on the agreement between stroke volume by non-invasive pulse wave analysis and Doppler ultrasound in healthy volunteers.

Background: Stroke volume can be estimated beat-to-beat and non-invasively by pulse wave analysis (PWA). However, its reliability has been questioned during marked alterations in systemic vascular resistance (SVR). We studied the effect of SVR on the agreement between stroke volume by PWA and Doppler ultrasound during reductions in stroke volume in healthy volunteers.

Hemodynamic effects of supplemental oxygen versus air in simulated blood loss in healthy volunteers: a randomized, controlled, double-blind, crossover trial.

Background: Trauma patients frequently receive supplemental oxygen, but its hemodynamic effects in blood loss are poorly understood. We studied the effects of oxygen on the hemodynamic response and tolerance to simulated blood loss in healthy volunteers.

Methods: Fifteen healthy volunteers were exposed to simulated blood loss by lower body negative pressure (LBNP) on two separate visits at least 24 h apart.

Effects of supplemental oxygen on systemic and cerebral hemodynamics in experimental hypovolemia: Protocol for a randomized, double blinded crossover study.

Supplemental oxygen is widely administered in trauma patients, often leading to hyperoxia. However, the clinical evidence for providing supplemental oxygen in all trauma patients is scarce, and hyperoxia has been found to increase mortality in some patient populations. Hypovolemia is a common finding in trauma patients, which affects many hemodynamic parameters, but little is known about how supplemental oxygen affects systemic and cerebral hemodynamics during hypovolemia.

Cerebral blood flow velocity during simultaneous changes in mean arterial pressure and cardiac output in healthy volunteers.

Purpose: Cerebral blood flow (CBF) needs to be precisely controlled to maintain brain functions. While previously believed to be autoregulated and near constant over a wide blood pressure range, CBF is now understood as more pressure passive. However, there are still questions regarding the integrated nature of CBF regulation and more specifically the role of cardiac output.