Efficacy of dexmedetomidine injected into axillary sheath in alleviating tourniquet pain during brachial plexus block with ropivacaine / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the efficacy of dexmedetomidine injected into axillary sheath in alleviating the tourniquet pain during brachial plexus block with ropivacaine.Methods Sixty ASA physical status Ⅰ or Ⅱ patients,aged 18-60 yr,weighing 52-85 kg,scheduled for the replantation of amputated finger,were randomly divided into 2 equal groups (n =30 each)ropivacaine group (group R) and dexmedetomidine mixed with ropivacaine group (group DR).All patients underwent axillary brachial plexus block guided by a nerve stimulator.When the intensity of electric stimulation ≤ 0.4 mA,flexion of fingers or wrist still existed,and the local anesthetic was injected into the axillary sheath.0.5％ ropivacaine 40ml was injected in group R.0.5％ ropivacaine mixed with 100μg dexmedetomidine 40ml was injected in group DR.The pressure of inflation was set at 200-250mmHg,and the stress duration was 120 min.Tourniquet pain and the level that the patients could tolerate was evaluated using visual analog scale (VAS) at 120 min of stress status.The patient' s satisfaction with anesthesia was rated and the development of adverse cadiovascular events and local and systemic adverse reactions were recorded.Excessive sedation was measured with Ramsay score in group DR.Results Compared with group R,the tourniquet pain that the patients could tolerate was significantly increased,the severity of tourniquet pain was reduced and the incidence of adverse cadiovascular events was decreased in group DR (P ＜ 0.01).No serious tourniquet-related complications were observed in both groups.No patients developed excessive sedation in group DR.Conclusion Dexmedetomidine 100μg injected into the axillary sheath can safely and effectively alleviate the tourniquet pain when used during brachial plexus block with ropivacaine.