Intravenous Amiodarone and Sotalol Impair Contractility and Cardiac Output, but Procainamide Does Not: A Langendorff Study.

Introduction: Direct comparison of the effects of antiarrhythmic agents on myocardial performance may be useful in choosing between medications in critically ill patients. Studies directly comparing multiple antiarrhythmic medications are lacking. The use of an experimental heart preparation permits examination of myocardial performance under constant loading conditions.

Hemodynamic Effects of Lipid-Based Oxygen Microbubbles via Rapid Intravenous Injection in Rodents.

Purpose: Low oxygen levels, or hypoxemia, is a common cause of morbidity and mortality in critically ill patients. Hypoxemia is typically addressed by increasing the fraction of inspired oxygen, the use of mechanical ventilation, or more invasive measures. Recently, the injection of oxygen gas directly into the bloodstream by packaging it within lipid-based oxygen microbubbles (LOMs) has been explored.

Rodent Working Heart Model for the Study of Myocardial Performance and Oxygen Consumption.

Isolated working heart models have been used to understand the effects of loading conditions, heart rate and medications on myocardial performance in ways that cannot be accomplished in vivo. For example, inotropic medications commonly also affect preload and afterload, precluding load-independent assessments of their myocardial effects in vivo. Additionally, this model allows for sampling of coronary sinus effluent without contamination from systemic venous return, permitting assessment of myocardial oxygen consumption.

Effects of commonly used inotropes on myocardial function and oxygen consumption under constant ventricular loading conditions.

Inotropic medications are routinely used to increase cardiac output and arterial blood pressure during critical illness. However, few comparative data exist between these medications, particularly independent of their effects on venous capacitance and systemic vascular resistance. We hypothesized that an isolated working heart model that maintained constant left atrial pressure and aortic blood pressure could identify load-independent differences between inotropic medications.

Bulk manufacture of concentrated oxygen gas-filled microparticles for intravenous oxygen delivery.

Self-assembling, concentrated, lipid-based oxygen microparticles (LOMs) have been developed to administer oxygen gas when injected intravenously, preventing organ injury and death from systemic hypoxemia in animal models. Distinct from blood substitutes, LOMs are a one-way oxygen carrier designed to rescue patients who experience life-threatening hypoxemia, as caused by airway obstruction or severe lung injury. Here, we describe methods to manufacture large quantities of LOMs using an in-line, recycling, high-shear homogenizer, which can create up to 4 liters of microparticle emulsion in 10 minutes, with particles containing a median diameter of 0.

Oxygen gas-filled microparticles provide intravenous oxygen delivery.

We have developed an injectable foam suspension containing self-assembling, lipid-based microparticles encapsulating a core of pure oxygen gas for intravenous injection. Prototype suspensions were manufactured to contain between 50 and 90 ml of oxygen gas per deciliter of suspension. Particle size was polydisperse, with a mean particle diameter between 2 and 4 μm.