Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02393677 |
| Other study ID # |
DN57/FM |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
March 15, 2015 |
| Last updated |
October 6, 2015 |
| Start date |
July 2011 |
| Est. completion date |
July 2012 |
Study information
| Verified date |
October 2015 |
| Source |
Government Medical College, Haldwani |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
India: Indian Council of Medical Research |
| Study type |
Interventional
|
Clinical Trial Summary
80 American Society of Anesthesiologists (ASA) grade I-II patients, 18-60 years
old,scheduled for elective upper limb orthopaedic surgery under supraclavicular brachial
plexus block, were included in this prospective study. The patients were randomly assigned
to group R (Ropivacaine alone) and group RD (Ropivacaine and dexmedetomidine) (40 patients
in each group). Group R received Ropivacaine 0.50% (30 cc) + placebo and group RD received
Ropivacaine 0.50% (30 cc) + dexmedetomidine 1 µg/kg.
Description:
After Institutional Ethical Committee approval and written informed consent, a prospective,
randomized, double-blinded study was carried out on 80 ASA Grade I and II patients of either
sex, aged 18-60 years, undergoing various orthopaedic surgeries on the upper limb under
supraclavicular brachial plexus block. A power analysis was performed to determine the
necessary number of patients for each group based on duration of analgesia. With a 2-sided
type I error of 5% and study power at 80%, it was estimated that 38 patients would be needed
in each group in order to detect a difference of 35 min in the duration of analgesia between
the 2 groups. The study was conducted in two groups of 40 patients each. Patients were
randomly chosen by computer-generated random selection to one of the following groups:
Group R: Ropivacaine 0.50% (30 cc) + Placebo Group RD: Ropivacaine 0.50% (30 cc) +
Dexmedetomidine 1 µg/kg Randomization was performed by an independent statistician and
concealed from patients and investigators until completion of statistical analysis. Patients
were instructed preoperatively about use of the verbal rating scale (VRS) for pain
assessment (VRS: 0 = no pain, 10=worst pain possible). On arrival in the operation room,
baseline heart rate, blood pressure and oxygen saturation were recorded. An intravenous line
was secured in the unaffected limb and Ringer's lactate was started. Patients were given
midazolam intravenous (IV) (0.03 mg/kg) as premedication 10-15 min before beginning each
blocks technique. Subcutaneous injection with 2 mL of 2% lidocaine was administered at the
needle insertion site. All the patients received brachial plexus block through the
supraclavicular approach by an experienced anesthesiologist different from the one assessing
the patient intra- and post-operatively. Both were blinded to the treatment groups. Neural
localization was achieved by using a nerve locator (Stimuplex® Dig RC, B.Braun, Melsungen
AG, Melsungen, Germany) connected to a 22 G, 50-mm-long stimulating needle (Stimuplex,
Braun, Germany). The location end point was a distal motor response with an output lower
than 0.5 milliampere (mA).
Following negative aspiration, 30 mL of a solution containing local anesthetic combined with
placebo or dexmedetomidine as mentioned above was injected and the use of Dexmedetomidine
was off-label. A 5-min compression was performed to facilitate an even drug distribution.
Sensory blockade was assessed every 3 min and motor block was evaluated every 5 min within
the first 30 min following completion of drug administration. Sensory block was confirmed by
pinprick sensation using a 23-G needle in all dermatomes of the brachial plexus (C5-T1) i.e.
median nerve, radial nerve, ulnar nerve and musculocutaneous nerve. Sensory onset was
considered when there was a dull sensation to pin prick along the distribution of any of
these nerves (Grade 1). Complete sensory block was considered when there was complete loss
of sensation to pin prick.
Sensory block was graded as- Grade 0 Sharp pin felt Grade 1 Analgesia, dull sensation felt
Grade 2 Anesthesia, no sensation felt
Motor blockade was evaluated by the ability to flex the elbow and hand against gravity as
follows :
Grade 1 Ability to flex and extend the forearm Grade 2 Ability to flex or extend only the
wrist and fingers Grade 3 Ability to flex or extend only the fingers Grade 4 Inability to
move the forearm, wrist, and fingers Onset of motor block was defined as the time from
injection of local anesthetic mixture until achieving a reduction in motor power to grade 3
or less. The block was considered incomplete when any of the segments supplied by median,
radial, ulnar and musculocutaneous nerve did not have analgesia even after 30 min of drug
injection. These patients were supplemented with intravenous fentanyl (2 μg/ kg) and
midazolam (0.03 mg/kg). When more than one nerve remained unaffected, it was considered a
failed block. In this case, general anesthesia was given intraoperatively. Patients were
monitored for hemodynamic variables such as heart rate, blood pressure and oxygen
saturation.
