Backgroud and aims: Dexmedetomidine and propofol infusions are increasingly being used to ensure intraoperative patient immobility in the absence of muscle relaxants during parotidectomy. The primary aim of our study was to assess the effectiveness of transtracheal block as an adjunct to general anesthesia in providing patient immobility during total parotidectomy, as compared to dexmedetomidine infusion.
Material and methods: This prospective, randomized study was conducted in 58 patients. Group A patients received a transtracheal injection of 4 ml of 4% lidocaine before induction whereas in Group B, dexmedetomidine 1 mcg/kg was administered intravenously. Following induction and intubation, anesthesia was maintained with oxygen, nitrous oxide, and isoflurane and dexmedetomidine was administered in Group B at a rate of 0.7 mcg/kg/h. In both the groups, if the patient moved, bucked, or if there were signs of inadequate depth of anesthesia, plane of anesthesia was deepened with a bolus of propofol 0.5 mg/kg intravenously. Mann-Whitney U-test and Fisher's exact test were used for statistical analysis.
Results: The number of patients who moved in the transtracheal group was significantly less as compared to dexmedetomidine group (3 vs. 11). Mean heart rates (HRs) were comparable in both groups till 10 min, but between 15 and 180 min, Group B had significantly low HR. Systolic blood pressure (SBP) was significantly high at 10 min following dexmedetomidine bolus in Group B. Though Group B showed low SBP values as compared to Group A from 10 min following induction, the difference became significant between 45 and 180 min. Changes in mean arterial blood pressures followed a similar trend as with SBP.
Conclusion: Transtracheal lidocaine ensured patient immobility with hemodynamic stability during total parotidectomy with nerve stimulation studies as compared to intraoperative dexmedetomidine infusion.
Keywords: Dexmedetomidine; parotidectomy; transtracheal lidocaine.