[Hemodynamic and metabolic evaluation of dexmedetomidine and remifentanil continuous infusion in videolaparoscopic...

Dexmedetomidine has been used for sedation and as coadjuvant drug in general anesthesia. This study aimed at evaluating cardiovascular and sympathetic-adrenal responses to tracheal intubation and pneumoperitoneum inflation with dexmedetomidine, as compared to remifentanil during anesthesia with sevoflurane for videolaparoscopic cholecystectomy.

Forty two physical status ASA I or II patients, aged 25 to 55 years, were randomly distributed in two groups: GI and GII. Anesthesia was induced with 1 microg.kg-1 dexmedetomidine (GI) or remifentanil (GII) continuous infusion for 10 minutes, followed by propofol and cisatracurium. Anesthesia was maintained with 0.7 microg.kg-1.h-1 dexmedetomidine or 0.5 microg.kg-1.h-1 remifentanil continuous infusion and different sevoflurane concentrations. SBP, DBP and HR were recorded in the following moments: M1 - before initial drug infusion; M2 - after end of initial drug infusion; M3 - after tracheal intubation; M4 - before pneumoperitoneum; M5 - after pneumoperitoneum; M6 - five minutes after pneumoperitoneum deflation; M7 - after tracheal extubation. Epinephrine and norepinephrine were dosed in M4, M5 and M6. Sevoflurane expired concentration (EC), EC/MAC ratio and sevoflurane consumption were recorded in M4, M5 and M6.

SBP and DBP variations were higher in the dexmedetomidine group in M4 and M5. HR, epinephrine and norepinephrine levels were similar between groups. Sevoflurane EC was higher in M4 and M6 for GI, as well as EC/MAC ratio. There has been a higher sevoflurane consumption in GI, with a trend to less analgesics and anti-emetics consumption.

In the conditions of our study, dexmedetomidine has inhibited catecholamine release during tracheal intubation and pneumoperitoneum, however, has not prevented blood pressure increase in response to peritoneal inflation.