Arthroscopic Knee Surgery, Dexmedetomidine, Femoral Nerve Block
Conditions
Keywords
femoral nerve block, peri-neural dexmedetomidine
Brief summary
The duration of sensory block after single dose of long acting local anesthetics is not sufficient to avoid the postoperative use of opioids. Alpha-2 adrenoceptor agonists such as clonidine have been shown to increase the duration of peripheral nerve block. Dexmedetomidine is a more potent and selective α-2-adrenoceptor compared to clonidine. To the best of our knowledge, the use of Dexmedetomidine in different dose levels as adjuvant to local anesthetic was not previously reported for femoral nerve block.
Interventions
ultrasound guided femoral nerve block with injection of 25 ml bupivacaine 0.5% perineurally with 1 ml dexmedetomidine 25, 50, or 75 microgram perineurally. After adequate assessment of femoral nerve block, patients will be transferred to the operating room to receive a standard general anesthesia.
DRUGPlacebo
Sponsors
Cairo University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
15 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* all patients with ASA physical status I or II, scheduled for arthroscopic knee surgery
Exclusion criteria
* Patients who are refusing regional block, patients with diabetic peripheral neuropathy, renal or hepatic dysfunction, inflammation or infection at the puncture site, and history of allergic reaction to study medications
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| duration of sensory block | Every 5 minutes for the first 30 minutes after end of study medications injection, then postoperatively every 2 hours till complete recovery of normal sensation. | the time interval between the onset of the sensory block and the complete resolution of normal sensation. Over a period of 30 min after injection of the study medications and every 2 hours postoperatively till complete recovery of normal sensation; a blinded investigator will assess sensory block with pinprick test using a 3-point scale: 0 ═ complete loss of sensation, 1 ═ partial loss of sensation and 2 ═ normal sensation. Pinprick test will be done in comparison to the contralateral area at the sensory distribution of the femoral nerve. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Onset of sensory block | up to 30 minutes after the end of injection | the time elapsed between the end of injection and the development of complete sensory block |
| Onset of motor block | up to 30 minutes after the end of injection | the time elapsed between the end of injection and the development of complete motor block |
| visual analogue pain scores (VAS) | 2hours post operative and for 24hours | Visual analogue pain scores (resting and dynamic VAS) will be assessed at 2, 4, 6, 8, 12, 16, and 24 hours postoperatively. |
| Richmond Agitation-Sedation Score (RASS) | 2hours post operative and for 24hours | Richmond Agitation-Sedation Score (RASS) will be assessed at 2, 4, 6, 8, 12, 16, and 24 hours postoperatively. |
| Time to first request of postoperative rescue analgesic | over the first postoperative 24hours | the time interval between the onset of successful sensory block and the first request to postoperative analgesia |
| total morphine consumption | The first 24 hours postoperatively | The total dose of morphine needed by the patient postoperatively till 24 hours. |
| perioperative hemodynamic parameters | will be recorded at 0, 15, 30 minutes after femoral nerve block, then every 10 minutes intraoperatively, and every 2 hours postoperative for a period of 12 hours. | Vital signs (heart rate and arterial blood pressure) will be recorded at 0, 15, 30 minutes after femoral nerve block, then every 10 minutes intraoperatively, and every 2 hours postoperative for a period of 12 hours. |
| incidence of side effects. | from the injection time till 24 hours postoperatively | Adverse events will be defined as hypotension (a 30% decrease in systolic blood pressure in relation to the baseline value), bradycardia (heart rate less than 60 beats per minute), desaturation (SpO2 \< 90% on room air) and postoperative nausea and/or vomiting. |
| duration of motor block | Every 5 minutes for the first 30 minutes after end of study medications injection, then postoperatively every 2 hours till complete recovery of motor power. | The time interval between the onset of the motor block and the complete resolution of the motor power in quadriceps muscle. Over a period of 30 min after injection of the study medications and every 2 hours postoperatively till complete recovery of motor power; a blinded investigator will assess the motor block using a 3-point scale where: 0 ═ no movement, 1 ═ reduced motor strength, but some perceptible movement, and 2 ═ normal motor function. |
Countries
Egypt
Outcome results
None listed