High-dose remifentanil increases blood pressure and heart rate mediated by sympatho-activation in conscious rats

Purpose The ultra-short-acting μ-opioid receptor agonist, remifentanil, is commonly used in clinical anesthesia; however, there are limited data about the hemodynamic effects of remifentanil itself without anesthetics. We investigated the effects of an ultra-short-acting μ-opioid receptor agonist, remifentanil, on cardiovascular and sympathetic function in conscious rats.