myocardial oxygen supply-demand ratio
Balance between coronary oxygen delivery and myocardial oxygen consumption, critical for preventing ischemia.
Full Definition
The myocardial oxygen supply-demand ratio represents the balance between coronary oxygen delivery and myocardial oxygen consumption, serving as a fundamental concept in cardiac anesthesia management. Oxygen supply depends on coronary blood flow, hemoglobin concentration, and arterial oxygen saturation, while demand is determined by heart rate, contractility, preload, and afterload. An unfavorable ratio predisposes to myocardial ischemia and should be optimized throughout the perioperative period. Anesthetic management focuses on maintaining adequate coronary perfusion pressure while minimizing factors that increase oxygen consumption, such as tachycardia, hypertension, and excessive sympathetic stimulation.
In Context
- "The anesthesiologist carefully monitored the myocardial oxygen supply-demand ratio throughout the procedure to prevent ischemia." — Anesthesia record
- "Optimizing the myocardial oxygen supply-demand ratio required balancing coronary perfusion pressure with heart rate control." — Case discussion