[Remifentanil: does the infusion regimen make a difference in the prevention of hemodynamic responses to tracheal intubation?].
OBJECTIVE
High doses of opioids decrease the hemodynamic response to tracheal intubation. However, the slow recovery profile of traditional opioids may limit the use of high doses. Remifentanil has a fast time of onset and is short acting, which differentiates it from the other drugs in this class. The primary objective of this study was to verify the hypothesis that there is no need to initiate the administration of remifentanil before the induction with propofol.


METHODS
Thirty patients, divided in two groups, who received total intravenous anesthesia, were evaluated. In Group 1, the infusion of remifentanil (0.3 microg.kg-1.min-1) was initiated two minutes before induction, and in Group 2, at the same time of the induction. Systolic, diastolic, and mean arterial blood pressure (SBP, DBP, MAP), heart rate (HR), concentration of propofol (CEF-prop) and remifentanil (CEF-remi) in the effector area in three moments: baseline (M0), after losing verbal contact (M1), and after tracheal intubation (M2) were evaluated.


RESULTS
There were significant reductions in blood pressure in both groups at M1 and M2. CEF-remi was greater in Group 1, at M1, and greater in Group 2, at M2 (p < 0.05). There was a significant statistical correlation between the vascular overload index (VOI) and the variation of the systolic pressure after the loss of verbal contact in Group 1 (r = -0.80; p < 0.01) and in Group 2 after tracheal intubation (r = -0.60; p < 0.01).


CONCLUSIONS
Remifentanil administered two minutes before induction with propofol did not offer additional cardiovascular protection to tracheal intubation. This suggests that it is not necessary to start the infusion of remifentanil two minutes before anesthetic induction.
Nora
Fernando Squeff
FS
Hospital de Clínicas de Porto Alegre.
Klipel
Rodrigo
R
Ayala
Gustavo
G
Oliveira Filho
Getúlio Rodrigues de
GR