Optimal Single-dose Intrathecal Dexmedetomidine for Postoperative Analgesia After Lower Limb Surgery
Overview
- Phase
- Not Applicable
- Intervention
- Intrathecal dexmedetomidine
- Conditions
- Lower Limb Surgery
- Sponsor
- Mansoura University
- Enrollment
- 15
- Locations
- 1
- Primary Endpoint
- Duration of analgesia
- Last Updated
- 9 years ago
Overview
Brief Summary
Spinal anesthesia is a commonly used technique for lower limb surgeries offering better quality of postoperative analgesia, lower incidence of side effects, and shorter post-anesthesia care unit stay than general anesthesia. However, the relatively short duration of action of the currently available local anesthetics (LAs) make these advantages short-lived.
The risk for local anesthetic toxicity (LAST) increases with the trials to use higher concentrations or volumes of intrathecal local anesthetics to increase the duration of analgesia.
Dexmedetomidine has the potential to prolong the duration of perioperative analgesia without the need for using high doses of local anesthetics and hence with decreasing the potential risk of local anesthetic, but the increased likelihood adverse effects such as short term bradycardia and prolonged duration of motor block may offset these benefits.
Detailed Description
The aim of this study is to determine the optimal single-dose of intrathecal dexmedetomidine that prolongs the analgesic duration with the least possible side effects. With the patients in the sitting position and the use of complete aseptic technique, 25G Whitacre spinal needles will be introduced through L2-L4 interspaces and after observing free flow of the CSF, a 3ml volume including bupivacaine 12.5mg in conjunction with dexmedetomidine (3 µg) will be injected in the first case, then the patient will be turned supine. The dose of intrathecal DEX given to the next patient will be guided by modified Dixon's up-and-down method using 1.5 mg as a step size, which assumed to be of clinical importance.
Investigators
Eligibility Criteria
Inclusion Criteria
- •American Society of Anesthesiologists physical class I to II.
- •Patients scheduled for elective lower limb surgeries.
Exclusion Criteria
- •Morbid obese patients.
- •Severe or uncompensated cardiovascular disease.
- •Significant renal disease.
- •Significant hepatic disease.
- •Pregnancy.
- •Lactating .
- •Heart block.
- •Bradyarrhythmias.
- •Receiving adrenergic receptor antagonist medications.
- •Receiving calcium channel blockers.
Arms & Interventions
Intrathecal dexmedetomidine
Up-down sequential allocation The dose of intrathecal DEX given to the next patient will be guided by modified Dixon's up-and-down method using 1.5 mg as a step size, which assumed to be of clinical importance
Intervention: Intrathecal dexmedetomidine
Outcomes
Primary Outcomes
Duration of analgesia
Time Frame: For 13 hours after surgery
The duration of analgesia, defined as the time from administering of intrathecal study solution (T0) to the time for the first rescue analgesic request
Secondary Outcomes
- Cumulative tramadol consumption(For 24 hours after surgery)
- Onset of motor blockade(For 2 hours after initiation of spinal anesthesia)
- Postoperative pain score(For 24 hours after surgery)
- Onset of sensory blockade(For 1 hour after initiaion of spinal anesthesia)
- Highest dermatome level of sensory blockade(For 4 hours after initiation of spinal anesthesia)
- Time to motor regression(For 6 hours after initiation of spinal anesthesia)
- Sedation score(For 24 hours after initiation of spinal anesthesia)
- Postoperative nausea and vomiting(For 24 hours after initiation of spinal anesthesia)
- Intraoperative bradycardia(For 4 hours after initiation of spinal anesthesia)
- Intraoperative use of supplemental fentanyl(For 4 hours after initiation of spinal anesthesia)
- Intraoperative use of ephedrine(For 4 hours after initiation of spinal anesthesia)
- Intraoperative use of midazolam(For 4 hours after initiation of spinal anesthesia)
- Intraoperative use of atropine(For 4 hours after initiation of spinal anesthesia)