The effects of intravenous fentanyl and intravenous fentanyl combined with bupivacaine infiltration on the hemodynamic response to skull pin insertion

This study was conducted to compare the effects of intravenous fentanyl and intravenous fentanyl combined with bupivacaine infiltration on the hemodynamic response to skull pin insertion. 120 ASA I-II patients scheduled for elective craniotomy were included. The fentanyl group (group F, n = 60) received fentanyl during induction and prior to skull pin insertion (2 and 1 microg . kg, respectively). The fentanyl-bupivacaine group (group FB, n = 60) received the same doses of fentanyl as well as scalp infiltration with 0.25% bupivacaine. The heart rate (HR) was not significantly different between the groups. HR, at 5 minutes after skull pin insertion in the group F and at 1 and 5 minutes after skull pin insertion in group FB, significantly decreased in comparison to the baseline values (P < 0.05). In both groups, HR at 1 and 5 minutes after skull pin insertion was significantly lower than HR just before skull pin insertion (P < 0.05). In group FB, the mean arterial pressure (MAP) at 1 and 5 minutes after skull pin insertion were significantly lower than that in group F (P < 0.05). In group F, MAP at 1 minute after skull pin insertion was higher than that of just before skull pin insertion (P < 0.05); however, MAP at 5 minutes after skull pin insertion was lower than that of just before skull pin insertion (P < 0.05). In group FB, MAP at 1 and 5 minutes after skull pin insertion was lower than that of just before skull pin insertion (P < 0.05). The hemodynamic response to skull pin insertion was effectively suppressed with both methods. Still, the addition of scalp infiltration to fentanyl did not provide any additional benefit. Administering an additional dose (1 microg . kg) of fentanyl just before skull pin insertion is recommended as a simple and effective option that requires no extra time.