Journal of Research in Medical Sciences (Jan 2012)
The effects of dexmedetomidine on hemodynamic responses to tracheal ntubation in hypertensive patients: A comparison with esmolol and sufentanyl
Abstract
Background: Hypertension and tachycardia caused by tracheal intubation can be detrimental in hypertensive patients. This study was conducted in order to compare the effects of dexmedetomidine on hemodynamic response to tracheal intubation in hypertensive patients with esmolol and sufentanyl. Methods: Sixty hypertensive patients scheduled for noncardiac surgery under general anesthesia were randomly as-signed to receive one of the three drugs before induction of anesthesia. Groups I, II, and III respectively received esmo-lol (100 mg) dexmedetomidine (1 μg/kg) and sufentanyl (0.25 μg/kg). Heart Rate (HR), systolic (SAP) and diastolic (DAP) arterial pressures were recorded before drug administration (baseline; T1), after drug administration (T2), after induction of anesthesia (T3), immediately after intubation (T4) and 3, 5 and 10 minutes after intubation (T5, T6, and T7, respectively). The mean percentage variations from T1 to T4 were calculated for all variables (HR, SAP and DAP). Thiopental dose, onset time of vecuronium and intubation time were also assessed. Results: No differences were observed between the three groups regarding demographic data (p > 0.05). Median thi-opental dose was significantly lower in Group II (325 mg; range: 250-500) compared to Group I (425 mg; range: 325-500; p < 0.01) and Group III (375 mg; range: 275-500; p = 0.02). The onset time of vecuronium was longest in Group I (245.2 ± 63 s vs. 193.9 ± 46.6 s and 205.5 ± 43.5 s; p < 0.01 and p < 0.05). In Group I, HR significantly decreased after drug administration compared to baseline (83.8 ± 20.4 vs. 71.7 ± 14.8; p = 0.002). Compared to the baseline (90.4 ± 8.4), DAP decreased after induction and remained below baseline values at T5, T6 and T7 (71.3 ± 12.8, 76.2 ± 10.7, 68.9 ± 10.8 and 62.1 ± 8.7, respectively; p < 0.05) in Group II. According to the mean percen-tage variation, a significant reduction in HR was assessed in Group II compared to Group III (-13.4 ± 17.6% vs. 11.0 ± 27.8%; p = 0.003). Increment in SAP was significant in Group I when compared to Group II (9.8 ± 20.9% vs. -9.2 ± 20.2%; p < 0.05). Increment in DAP in Group III was significant compared to Group II (0.07 ± 19.8 vs. 24.5 ± 39.1; p < 0.05). Conclusions: In hypertensive patients, administration of dexmedetomidine before anesthesia induction blunts the he-modynamic response to tracheal intubation and reduces the thiopental dose.
