Clinical Trial: Addition of Dexmedetomidine to Ropivacaine-induced Supraclavicular Block (ADRIB Trial)

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Addition of Dexmedetomidine to Ropivacaine-induced Supraclavicular Plexus Block, a Randomized Controlled Study

Brief Summary: Dexmedetomidine, an alpha 2-adrenoreceptor agonist, has been found to exerts an excellent influences on the filed of perineural block. It could shorten the onset time and prolong the duration of the nerve block and improved postoperative pain. However, Dexmedetomidine-induced bradycardia or hypotension has recently attracted considerable attention because of potentially grave consequences, including sinus arrest and refractory cardiogenic shock. A low dose may help minimize cardiovascular risks associated with dexmedetomidine. However, few studies have addressed the clinical effects of low-dose dexmedetomidine as an perineural adjuvant. The present study was designed to test the hypothesis that low-dose dexmedetomidine added to ropivacaine would safely enhance the duration of analgesia without adverse effects when compared with ropivacaine alone. Investigators will conduct a single-center, prospective, randomized, triple-blind, controlled trial in patients undergoing elective forearm and hand surgery under ultrasound-guided supraclavicular brachial plexus block using either ropivacaine or ropivacaine plus low-dose dexmedetomidine. The primary outcome is self-reported duration of analgesia . Secondary outcomes include onset time and duration of motor and sensory block, total postoperative analgesics, and safety assessment (adverse effects and postoperative abnormal sensation).

Detailed Summary: Dexmedetomidine, an alpha 2-adrenoreceptor agonist, has been found to exerts an excellent influences on the filed of perineural block. It could shorten the onset time and prolong the duration of the nerve block and improved postoperative pain. However, Dexmedetomidine-induced bradycardia or hypotension has recently attracted considerable attention because of potentially grave consequences, including sinus arrest and refractory cardiogenic shock. Although meta-analysis showed that perineural dexmedetomidine as a local anaesthetic adjuvant for neuraxial and peripheral nerve blocks produced reversible bradycardia in only 7% of brachial plexus block patients and no effect on the incidence of hypotension, various clinical studies reported a significant decrease in heart rate. A low dose may help minimize cardiovascular risks associated with dexmedetomidine. However, few studies have addressed the clinical effects of low-dose dexmedetomidine as an perineural adjuvant. The present study was designed to test the hypothesis that low-dose dexmedetomidine, which till today has not been reported in the literature, added to ropivacaine for brachial plexus block would safely enhance the duration of analgesia without adverse effects when compared with ropivacaine alone. Investigators will conduct a single-center, prospective, randomized, triple-blind, controlled trial in patients undergoing elective forearm and hand surgery under ultrasound-guided supraclavicular brachial plexus block using either 20 mL of 0.5% ropivacaine or 0.5% ropivacaine plus 30 microg dexmedetomidine. The primary outcome is self-reported duration of analgesia . Secondary outcomes include onset time and duration of motor and sensory block, total postoperative analgesics, and safety assessment (adverse effects including cardiovascular inhibitions and postoperative abnormal sensation). Data will be collected and analyzed in a blinded fashion.
Sponsor: Guangzhou First People's Hospital

Current Primary Outcome: Duration of analgesia [ Time Frame: up to 24 hours postoperatively ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• Blood pressure (BP) [ Time Frame: up to 24 hours postoperatively ]
  Noninvasive arterial BP is measured at the non-operated arm. episode of hypotension (30% decrease in mean BP in relation to baseline values) and hypertension (30% increase in mean BP in relation to baseline values) will be recorded.
• Heart rate (HR): [ Time Frame: up to 24 hours postoperatively ]
  HR, bradycardia (HR < 50 beats/min), and tachycardia (HR > 100 beats/min) will be recorded at the same time as BP recording.
• Peripheral oxygen saturation (SpO2) [ Time Frame: up to 24 hours postoperatively ]
  SpO2 and hypoxemia (SpO2 <90%) will be recorded at the same time as BP recording.
• Sensory block of median nerve [ Time Frame: up to 30 minutes after administration of block ]
  is defined by pinprick sensation using a 3-point scale (0-2, 0 = normal sensation, 1 = decreased pain sensation to pinprick, 2 = loss of pain sensation to pinprick) in the median nerve locations.
• Sensory block of ulnar nerve [ Time Frame: up to 30 minutes after administration of block ]
  Sensory block of ulnar nerve is defined by pinprick sensation using a 3-point scale (0-2, 0 = normal sensation, 1 = decreased pain sensation to pinprick, 2 = loss of pain sensation to pinprick) in the ulnar nerve locations.
• Sensory block of radial nerve [ Time Frame: up to 30 minutes after administration of block ]
  Sensory block of radial nerve is defined by pinprick sensation using a 3-point scale (0-2, 0 = normal sensation, 1 = decreased pain sensation to pinprick, 2 = loss of pain sensation to pinprick) in the radial nerve locations.
• Sensory block of musculocutaneous nerve [ Time Frame: up to 30 minutes after administration of block ]
  Sensory block of musculocutaneous nerve is defined by pinprick sensation using a 3-point scale (0-2, 0 = normal sensation, 1 = decreased pain sensation to pinprick, 2 = loss of pain sensation to pinprick) in the musculocutaneous nerve locations.
• Motor block of median nerve [ Time Frame: up to 30 minutes after administration of block ]
  Motor block of median nerve is defined by thumb and fifth finger pinch.
• Motor block of ulnar nerve [ Time Frame: up to 30 minutes after administration of block ]
  Motor block of ulnar nerve is defined thumb and second finger pinch.
• Motor block of radial nerve [ Time Frame: up to 30 minutes after administration of block ]
  Motor block of radial nerve is defined by finger abduction.
• Motor block of musculocutaneous nerve [ Time Frame: up to 30 minutes after administration of block ]
  Motor block of musculocutaneous nerve is defined by flexion of the elbow.
• Duration of motor block [ Time Frame: up to 24 hours postoperatively ]
  Duration of motor block is defined as the time interval between the administration of the block and the recovery of complete motor function of the hand and forearm assessed.
• Success rate of nerve block [ Time Frame: 30 minutes after administration of block ]
  A successful block is defined as surgery without patient discomfort and the need for supplementation of local infiltration or general anesthesia
• Postoperative analgesic requirement [ Time Frame: up to 24 hours postoperatively ]
  IV tramadol 50mg will be administered when postoperative pain >3, and be titrated up by 50 mg increments as needed for pain every 4 to 6 hours, with the maximum total dose of 250mg.
• Postoperative nausea and vomiting (PONV) [ Time Frame: up to 24 hours postoperatively ]
  The incidence of PONV will be recorded using a 4-point objective score (1 = no PONV;2 = mild nausea, no vomiting; 3 = excessive nausea or vomiting;4 = vomiting ≥2 times).
• Abnormal sensation of brachial plexus [ Time Frame: Day 1 ]
  Patient's self-reported abnormal sensation of the hand and forearm.

Original Secondary Outcome: Same as current

Information By: Guangzhou First People's Hospital

Dates:
Date Received: December 3, 2015
Date Started: December 2015
Date Completion:
Last Updated: August 10, 2016
Last Verified: August 2016