Intravenous Dexamethasone to Increase the Analgesic Duration of Interscalene Block

Not Applicable

Completed

Brief Summary: Interscalene brachial plexus block provides excellent but time limited analgesia. Intravenous dexamethasone increases the analgesic duration of a single-shot interscalene block with ropivacaine for shoulder arthroscopic surgery. We want to evaluate the effect of two different doses (dexamethasone 10 mg i.v. vs 4 mg i.v. vs placebo) on the analgesic duration of a single-shot inter scalene block. Our study hypothesis is that dexamethasone 4 mg i.v. is equivalent to dexamethasone10 mg i.v. in prolonging the analgesic duration of a single-shot interscalene block with ropivacaine.

Detailed Description: 75 patients will be randomly assigned to three groups:

* D10: dexamethasone 10 mg I.V. diluted in normal saline 20cc, immediately after inter scalene block

* D4: dexamethasone 4 mg I.V. diluted in normal saline 20cc, immediately after inter scalene block

* C: control: Normal saline 20cc I.V., immediately after inter scalene block. These patient will be recruited from 3 hospitals, with two surgeons performing the surgeries.

All patients will have their surgery under regional anesthesia only provided by the inter scalene plexus block, with ropivacaine 0.5% 20cc.

In the postoperative period, patients will be given analgesic medication on an as needed basis. They will be instructed to take the first analgesic medication once postoperative shoulder pain has reached \>3/10. They will note the time and day at which this outcome occurs.

Recruitment & Eligibility

Inclusion Criteria

Elective shoulder arthroscopy under ropivacaine single-shot interscalene brachial plexus block anesthesia (rotator cuff repair and shoulder decompression)
ASA I-III
Age 18-80 years old

Exclusion Criteria

Arm && Interventions

Group	Intervention	Description
Normal Saline 20 mL intravenous	Normal Saline	Normal saline 20 mL injected slowly during 30 seconds, immediately after performing interscalene brachial plexus block
Dexamethasone 10 mg intravenous	Dexamethasone	Dexamethasone 10 mg diluted with Normal Saline 17,5 mL i.v. (20 mL total) injected slowly during 30 seconds immediately after performing interscalene brachial plexus block
Dexamethasone 4 mg intravenous	Dexamethasone	Dexamethasone 4 mg diluted with Normal Saline 19 mL i.v. (20 mL total) injected slowly during 30 seconds, immediately after performing interscalene brachial plexus block

Primary Outcome Measures

Name	Time	Method
Duration of Analgesia	48 hours after surgery	Defined as the time between the performance of the block and the first analgesic request

Secondary Outcome Measures

Name	Time	Method
Pain Scores	every 6 hours during the first 48 hours after surgery	On a 11-points Verbal Numeric Scale 0-10 (0= no pain, 10= worst conceivable pain)
Residual Motor Block	24 hours and 48 hours	Scale of 0-2 (0:inability to move fingers, 1: fingers able to move, with diminished strength compared to non operated side, 2: No motor weakness of the fingers)
Patients Overall Satisfaction	48 hours	categorical data (1: very satisfied, would recommend this analgesia protocol to others, 0: not satisfied, would not recommend this analgesia protocol to others
Sleep Disturbance	24 hours and 48 hours	Sleep disturbance scale 0-10 (0: no sleep disturbance from pain, 10: worst conceivable sleep disruption from pain)

Locations (3): Hopital Pierre-Boucher
🇨🇦
Longueuil, Quebec, Canada
Maisonneuve-Rosemont Hospital
🇨🇦
Montreal, Quebec, Canada
Hopital Hotel-Dieu de Sorel
🇨🇦
Sorel, Quebec, Canada