Effects of fentanyl-lidocaine-propofol and dexmedetomidine-lidocaine-propofol on tracheal intubation without use of muscle relaxants.

The aim of this study was to compare the effects of fentanyl or dexmedetomidine when used in combination with propofol and lidocaine for tracheal intubation without using muscle relaxants. Sixty patients with American Society of Anesthesiologists stage I risk were randomized to receive 1 mu g/kg dexmedetomidine (Group D, n = 30) or 2 mu g/kg fentanyl (Group F, n = 30), both in combination with 1.5 mg/kg lidocaine and 3 mg/kg propofol. The requirement for intubation was determined based on mask ventilation capability, jaw motility, position of the vocal cords and the patient's response to intubation and inflation of the endotracheal tube cuff. Systolic arterial pressure, mean arterial pressure, heart rate and peripheral oxygen saturation values were also recorded. Rate pressure products were calculated. Jaw relaxation, position of the vocal cords and patient's response to intubation and inflation of the endotracheal tube cuff were significantly better in Group D than in Group F (p < 0.05). The intubation conditions were significantly more satisfactory in Group D than in Group F (p = 0.01). Heart rate was significantly lower in Group D than in Group F after the administration of the study drugs and intubation (p < 0.05). Mean arterial pressure was significantly lower in Group F than in Group D after propofol injection and at 3 and 5 minutes after intubation (p < 0.05). After intubation, the rate pressure product values were significantly lower in Group D than in Group F (p < 0.05). We conclude that endotracheal intubation was better with the dexmedetomidine lidocaine propofol combination than with the fentanyl lidocaine propofol combination. However, side effects such as bradycardia should be considered when using dexmedetomidine.