EFFECT OF PEROPERATIVE ADENOSINE ON THE REQUIREMENTS FOR INHALATION ANESTHESIA AND POSTOPERATIVE ANALGESIA IN SURGICAL PATIENTS

Abstract

In 1925, Lundy introduced the term "balanced anesthesia" for a combination of premedications, regional anesthesia and general anesthesia with one or more agents, including analgesics and muscle relaxants. Thus a combination of intravenous and inhalational drugs is commonly used to maintain hemodynamic stability during the intraoperative period.

Controversery exists regarding the optimal approach to control acute cardiovascular changes that occur in response to noxious surgical stimuli.

Adenosine, a naturally occurring nucleoside compound with potent sympatholytic properties, has been reported to potentiate the sedative effect of midazolam and to reduce the requirement for inhalational anesthetic and postoperative opioid analgesics. Systemic administration of the compound has been applied for vasodilation during surgical procedures and as a therapeutic as well as a diagnostic measure in cardiology. Adenosine is extremely labile i n the circulation with plasma half-life less than 10 seconds. In the CNS, the receptors mediating stimulatory and inhibitory effects of adenosine have been identified as A 1 A2A, A2B and A3• The antinociceptive effect is considered to be mediated through A1 adenosine receptor activation in CNS. Animal studies had demonstrated adenosine and adenosine-analogue mediated inhibitory