Intraoperative Complications
Conditions
Keywords
Anesthesia, Epidural, Pharmacology, Dose-Response Relationship, Drug, Sympathectomy, Photoplethysmography
Brief summary
This study aims to compare human subjects receiving epidural bupivacaine local anesthetic at different doses and concentrations and to assess the effect on vasodilatation (sympathectomy), sensory and motor block. The hypothesis is that the drug concentration is more important than drug dose in the determination of the extent and intensity of differential sympathetic, sensory and motor block following epidural local anesthetic.
Detailed description
There is controversy regarding the factors that determine the extent and intensity of epidural drug action. Most studies have focused on the inter-related triad of dose, concentration and volume. We compare three groups: group A: 10ml of 0.5% bupivacaine; group B: 10ml of 0.25% bupivacaine and group C: 40ml of 0.0625% bupivacaine. When comparing these groups, groups A & B have the same volume of epidural drug, and groups B & C have the same total dose. In particular this study compares different methods of assessing the sympathetic block (causing vasodilatation). These methods include skin temperature changes, hemodynamic changes and photoplethysmography.
Interventions
DRUGEpidural bupivacaine (dose/concentration/volume ranging)
Sponsors
Hadassah Medical Organization
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Patients scheduled for extracorporeal shock wave lithotripsy (ESWL) under epidural anesthesia between March to September 1999
Exclusion criteria
* graded as ASA 3 or higher, below 18 or above 70 years of age, if they had peripheral vascular disease, baseline neurological deficit, or had any other contraindication for regional anesthesia.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Index of sympathectomy: photoplethysmography derived amplitude-baseline ratio from foot and hand; data measured at time 0, 5, 10 and 20 min following epidural; data expressed as % change from baseline and as area under time effect curve. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Other indices of sympathectomy: | — |
| a. Photoplethysmography derived baseline change (ln (Blepi/Blo)); | — |
| b. Photoplethysmography derived time lag between pulse reaching hand and foot; | — |
| c. Blood pressure (mean, systolic, diastolic); | — |
| d. Skin temperature changes (finger and toe temperature change from baseline, toe-thigh and finger-arm temperature gradients). | — |
| 2. Sensory level (pinprick, touch, cold) | — |
| 3. Motor block (Bromage scale) | — |
| All assessments made at 0, 5, 10 and 20 minutes after epidural drug administration. | — |
Countries
Israel
Outcome results
None listed