Remifentanil decreases mandibular bone marrow blood flow during propofol or sevoflurane anesthesia in rabbits

The purpose of this study was to investigate the effect of remifentanil on the blood flow in rabbit oral tissues during propofol or sevoflurane anesthesia.

Thirty-two male tracheotomized Japanese white rabbits were anesthetized with propofol (P group) or sevoflurane (S group) under mechanical ventilation. Animals were further divided into 4 groups: adenosine triphosphate (ATP) treatment in the P group (P-ATP) (n = 8), remifentanil treatment in the P group (P-Remi) (n = 8), ATP treatment in the S group (S-ATP) (n = 8), and remifentanil treatment in the S group (S-Remi) (n = 8). Blood pressure, heart rate, common carotid artery blood flow (CABF), lingual mucosal blood flow (LMBF), and mandibular bone marrow blood flow (BMBF) were measured during each period before and during infusion of ATP or remifentanil.

Mean arterial pressure (MAP), CABF, LMBF, and BMBF showed a significant decrease in all 4 groups during infusion of the drug. Similarly, LMBF and BMBF showed significant decreases in both the ATP and remifentanil groups, whereas the decreases in MAP and CABF measured as percent change were greater in the ATP groups than in the remifentanil groups. A significant correlation was observed between CABF and BMBF in the S-Remi group. In both the P and S groups, the correlations between MAP and LMBF or BMBF were relatively strong when ATP was administered.

Our findings suggest that infusion of remifentanil during propofol or sevoflurane anesthesia reduces BMBF and LMBF, as does deliberate hypotension by use of ATP, without a major decrease in MAP.