The Application Of Dexmedetomidine As A Supplement To Cervical Plexus Lockb For Thyroidectomy

Objective To observe the effect of dexmedetomidine infusion as a supplement to cervical plexus block for thyroidectomy. To evaluate the feasibility and safety of analgesia and conscious sedation.Methods Sixty patients scheduled for thyroidectomy were randomly assigned to three groups with20cases for each. In group placebo (C) patients were received with0.375%ropivacaine for cervical plexus block; in group D1, patients were received a loading dose of0.5μg/kg Dexmedetomidine(10min, then followed by a maintenance dose of0.2μg·kg-1·h-1until the start of skin closure) then underwent cervical plexus block; in group D2patients were received0.375%ropivacaine and DEX (0.5μg/kg) for cervical plexus block. Mean arterial pressure, heart rate, Pulse Oxygen Saturation, Respiratory rate and Ramsay score were monitored at different time points, record pain block onset time, the efficacy of anesthesia, block durations. The patients were quiet supinning after entranced into the operating room(T0). Finished cervical plexus block after15minutes(T1). Immediately before cutting the skin(T2). At the time when isolated the upper or lower of thyriod(T3). At the time when the surgery was completely(T4). To observe if the patients were respiratory inhibition, hoarseness, hornor syndrome, sinus bradycardia, shin rash, vomiting during the anesthesia and surgery.Results There was no significant differences in three group’s sex, age, weight (P>0.05); Before anesthesia, the underlying value of MAP, HR, SpO2, RR and Ramsay score in three group were not statistically significant (P>0.05);MAP and HR increased significantly after cervical plexus block in group C(P<0.05); the Ramsay scales in group D1, D2were higher than in group C and the duration of pain block was longer in group D2than that of group C, group D1(P<0.05), the incidence rate of respiratory depression, hoarseness, hornor syndrome, sinus bradycardia, shin rash, vomiting has no statistical significance (P>0.05).Conclusion Dexmedetomidine can provide adequate sedation. Addition of dexmedetomidine to local anesthetic faster onset time of anesthesia and prolong the duration of pain block. Also dexmedetomidine is effective on the steady homodynamic and improve the efficacy of anesthesia.