Study to Find Optimal Dose of Local Spinal Anesthetic (Mepivacaine) Combined With Narcotic (Fentanyl) For Knee Surgery

Study Overview
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Brief Summary
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Prolonged motor block and delayed ability to walk are limitations of spinal anesthesia in ambulatory (same-day) surgery. This can be improved by lowering the dose of local anesthetic (a medication that, when injected around nerves, blocks nerve conduction, resulting in numbness and weakness) used in the spine, but too low a dose can result in an incomplete block (inadequate anesthesia) in some patients. There is evidence that adding a low dose of fentanyl, a narcotic, to mepivacaine enhances the anesthetic effect. The purpose of this study is to determine the lowest dose of mepivacaine, a local anesthetic, when combined with fentanyl, for which spinal anesthesia is adequate for ambulatory knee arthroscopy.

Official Title
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Optimal Dose of Spinal Mepivacaine Combined With Fentanyl For Knee Arthroscopy

Conditions
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Arthroscopic Knee Surgery

Intervention / Treatment
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* Procedure: Mepivacaine (24 mg) plus fentanyl
* Procedure: Mepivacaine (27 mg) plus fentanyl
* Procedure: Mepivacaine (30 mg) plus fentanyl
* Procedure: Mepivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects aged 18-60 Patients scheduled for simple knee arthroscopies, including meniscectomy, debridement, and plica. Exclusion Criteria: Subjects aged <18 or >60 Subjects greater than 190 cm in height Patients scheduled for ligament reconstruction or surgery involving bone Daily use of narcotics for greater than one week pre-op

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Mepivacaine 37.5 mg<br> | Procedure: Mepivacaine<br>* Mepivacaine 37.5 mg<br>|
| Active Comparator: Mepivacaine 30 mg plus fentanyl 10 µg<br> | Procedure: Mepivacaine (30 mg) plus fentanyl<br>* Mepivacaine (30 mg) and fentanyl (10 µg)<br>|
| Active Comparator: Mepivacaine 27 mg plus fentanyl 10 µg<br> | Procedure: Mepivacaine (27 mg) plus fentanyl<br>* Mepivacaine (27 mg) and fentanyl (10 µg)<br>|
| Active Comparator: Mepivacaine 24 mg plus fentanyl 10 µg<br> | Procedure: Mepivacaine (24 mg) plus fentanyl<br>* Mepivacaine (24 mg) and fentanyl (10 µg)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time From Spinal Administration to Block Regression to the S1 Dermatome in Post-Anesthesia Care Unit (PACU) | The time frame of the study for each patient only covers the period between time of surgery and time of discharge from the hospital, which is on the same day as the day of surgery | Participants will be followed for the duration of their recovery after surgery in the post-anesthesia care unit (PACU), an expected average of 2-4 hours. |