pulmonary vascular resistance
Also written as: PVR — pulmonary vascular resistance
Calculated hemodynamic parameter representing the resistance to blood flow through the pulmonary circulation.
Full Definition
A derived hemodynamic measurement calculated as the difference between mean pulmonary artery pressure and left atrial pressure (or PCWP) divided by cardiac output, expressed in Wood units or dynes·sec·cm⁻⁵. Normal PVR is 20-120 dynes·sec·cm⁻⁵ (0.25-1.5 Wood units). Elevated PVR indicates pulmonary hypertension and increased right heart afterload, which significantly impacts anesthetic management and surgical outcomes. In cardiac surgery, PVR assessment helps guide perioperative management, predicts right heart failure risk, and influences decisions regarding pulmonary vasodilator therapy. Accurate measurement requires simultaneous pressure and cardiac output monitoring.
Usage
Usage note: Specify units when documenting (Wood units or dynes·sec·cm⁻⁵); distinguish from systemic vascular resistance (SVR).
In Context
- "Preoperative catheterization revealed severely elevated pulmonary vascular resistance of 8.2 Wood units." — Preoperative assessment
- "The patient's pulmonary vascular resistance decreased from 640 to 280 dynes·sec·cm⁻⁵ following inhaled nitric oxide administration." — ICU progress note