Myocardial Systolic Function Increases During Positive Pressure Lung Inflation

Myocardial systolic function increases during positive pressure lung inflation.

Lung inflation with positive airway pressure may have rapid and dynamic effects on myocardial contractile function. We designed this study to assess the magnitude and time to onset of myocardial function changes during the initiation of single positive pressure lung inflation at clinically relevant inflation pressures. In 8 anesthetized 40-kg pigs, left ventricular pressures and volumes were me...

Regional myocardial systolic function during acute myocardial ischemia assessed by strain Doppler echocardiography.

OBJECTIVES We sought to evaluate if echocardiographic strain measurements could detect acute myocardial ischemia, and to compare this new method with myocardial velocity measurements and wall motion score index. BACKGROUND Tissue Doppler echocardiography (TDE) is a promising method for assessing regional myocardial function. However, myocardial velocities measured by tissue Doppler echocardio...

Left ventricular diastolic pressure-volume relations in rats with healed myocardial infarction. Effects on systolic function.

To determine the effects of healed myocardial infarction on the diastolic compliance of the left ventricle, we studied 36 rats 26 days after left coronary artery ligation. Peak cardiac output and stroke volume were measured under ether anesthesia during volume loading, and peak left ventricular developed pressure was determined during occlusion of the ascending aorta. During a slow infusion of ...

Crackles and instabilities during lung inflation

In a variety of physico-chemical reactions, the actual process takes place in a reactive zone, called the ‘‘active surface’’. We define the active surface of the lung as the set of airway segments that are closed but connected to the trachea through an open pathway, which is the interface between closed and open regions in a collapsed lung. To study the active surface and the time interval betw...

Intraocular Pressure during Continuous Positive Airway Pressure