The Effect of Fentanyl or Epinephrine Addition to Ropivacaine in Brachial Plexus Block

Abstract

Background: The administration of adjuncts to local anesthetics in brachial plexus block affects the onset of sensory or motor block and the duration of analgesia. But, the effect of opioid with ropivacaine is controversial, and epinephrine addition does not significantly affect the duration of analgesia. So, we evaluated the effects of fentanyl or epinephrine added to ropivacaine for brachial plexus block. Methods: Forty-five patients scheduled for upper extremity surgery (ASA 1, 2) were randomly divided into 3 groups: Group 1 received 0.5% ropivacaine 52 ml, Group 2 received 0.5% ropivacaine 52 ml with 1：200,000 epinephrine, and Group 3 received 0.5% ropivacaine 50 ml with fentanyl 100g. At 1-min intervals after injecting local anesthetic, sensory block was assessed in the C5-6 dermatome by pinprick testing and motor block was assessed at the shoulder by asking the patient to elevate the affected arm while keeping the elbow straight. Duration of analgesia (the time between injection and the onset of pain) and the duration of motor block (the time between injection and the restoration of shoulder mobility) were recorded. Results: No significant difference was observed in the onset of sensory or motor block, or in the duration of analgesia or motor block between the three groups. Conclusions: The addition of fentanyl or epinephrine to ropivacaine in brachial plexus block does not affect the onset of sensory or motor block, or the duration of analgesia or motor block.