Intraoperative Pain and Quality of Surgical Block During Shoulder Surgery Assessed by NOL Index

Intraoperative Pain and Quality of the Surgical Nerve Block During Arthroscopic Shoulder Surgery Assessed by the NOL Index When Comparing the Combined Suprascapular and Posterior Cord Nerve Blocks to the Interscalene Brachial Plexus Block

Postoperative analgesia for shoulder surgery is typically achieved by providing an interscalene brachial plexus block. However, a very common side effect of this block is hemi-diaphragmatic paralysis, a state which may not be tolerated in patients with pulmonary conditions such as COPD. Recently, clinicians have explored new ways to provide satisfactory analgesia while minimizing the pulmonary side effects of the interscalene nerve block. One of these solutions might be to offer the patient a suprascapular nerve block combined to a posterior cord block. Since these blocks are performed lower in the neck or under the clavicle, the phrenic nerve is less likely to be blocked. Thus, fewer respiratory side effects have been reported when using such blocks. This prospective observational study will evaluate the NOL response to surgical stimuli and the opioid requirements intraoperatively in patients undergoing shoulder arthroscopies with either a supraclavicular and posterior cord blocks or an interscalene block.

Study Design: Prospective, randomized open label non-inferiority trial. Subject Population: Adults scheduled to undergo elective shoulder arthroscopy Sample Size: 100 patients Study Duration: Starts February 2019 - Ends February 2021 - Interim analysis at 50 patients Study Center: Maisonneuve-Rosemont Hospital, CEMTL, Montreal, Quebec, Canada

Study Overview

• Status: Withdrawn
• Conditions: Shoulder Surgery; Regional Anesthesia Morbidity
• Intervention / Treatment: Procedure: Suprascapular Nerve Block + Posterior Cord Block; Procedure: Interscalene Brachial Plexus Block

Detailed Description

The main hypothesis of this study is that the suprascapular block combined with a posterior cord block is not inferior to the interscalene brachial plexus block in terms of intraoperative analgesia. We postulate that intraoperative opioid requirements will not differ significantly in patients who receive either block.

Our secondary objectives will consist in looking at the differences in intraoperative anesthetic consumption, NOL index alterations, postoperative opioid consumption, pain scores, arm motor block, diaphragmatic paresis, patient satisfaction and time for readiness to discharge from PACU. We hypothesize that these outcomes will be similar in both groups, with the exception of a potential reduction in arm motor block and diaphragmatic paresis in the combined suprascapular and posterior cord block group.

After having obtained institutional ethics board approval of the study, patients older than 18 years old, scheduled for a first elective shoulder arthroscopy under general anesthesia will be screened in the pre-anesthesia clinic. They will be approached and the whole study procedures will be explained extensively. Interested patients will be invited to sign the consent form (see appendix). Patients will have the right to opt out at any time. The investigators will meet the patients again on the morning of the surgery to address any concerns. After consent, a study number will be allocated to the patient in ascending order.

Two groups will be evaluated:

• Group A: single shot US-guided suprascapular nerve block with 5 mL ropivacaine 0.5%, then single shot US-guided posterior cord block with 10 ml ropivacaine 0.5%.
• Group B: single shot US-guided interscalene brachial plexus block with 15 mL ropivacaine 0.5%.

Tests will be done to evaluate the nerve block-induced loss of sensation to ice prior to entering the operating room (OR). Diaphragmatic excursion will be evaluated using an abdominal curvilinear ultrasound probe, and will be classified as being normal, paradoxical or immobile. Normal motion is caudad movement during inspiration. Paradoxical motion is cephalad movement during inspiration.

Once in the operating room, all routine monitors are connected. Moreover, the PMD TM monitor as well as the BIS® monitor are connected to the anesthesia machine and to the patient. Both study monitors are switched on and will record their respective indices continuously for the duration of the anesthesia. General anesthesia will be induced with propofol (1-2 mg/kg IV; Pharmascience Inc, Canada), remifentanil (1 µg/kg IV bolus; Teva, Canada) and rocuronium (0.6-1 mg/kg IV; Sandoz Canada Inc). A bolus of dexamethasone 4mg IV will be administered after induction of general anesthesia.

Patients will also have received oral acetaminophen 1g and celecoxib 400 mg preoperatively. Intubation with an endotracheal tube is performed once the patient is adequately paralyzed (no responses to the TOF stimulation). All drugs are given according to the adjusted body weight of the patient. This is calculated with Robinson's formula: where TBW is total body weight and IBW is ideal body weight (21-22). Immediately after intubation, anesthesia is maintained with desflurane while targeting a BIS value between 45 and 55, and a remifentanil infusion and boluses are used for a NOL below 25. At the end of anesthesia, when the surgeon starts closing the wounds, an IV bolus of hydromorphone 7 mcg/kg of adjusted body weight is administered. The remifentanil infusion and desflurane are discontinued when dressing starts. Emergence and extubation are done in the OR. All times (start skin closure, start dressing, stop desflurane and remifentanil) will be precisely reported in the CRF.

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Montréal, Quebec, Canada, H1T2M4
      • Hôpital Maisonneuve-Rosemont, CIUSSS de l'Est de l'Ile de Montréal

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ASA status 1,2,3.
• Age 18 years or older
• Elective shoulder arthroscopic surgery under general anesthesia and nerve block performed preoperatively

Exclusion Criteria:

• Serious cardiac arrhythmias (including atrial fibrillation) or unstable coronary artery disease.
• Coagulation disorders.
• Patient refusal.
• Anatomical disorders and/or neuropathic disease.
• BMI above 40.
• History of substance abuse.
• Chronic use of psychotropic and/or opioid.
• History of psychiatric diseases needing treatment.
• Contraindications to nerve block for shoulder surgery.
• Allergy to remifentanil or any drug in the study protocol.
• Failure of nerve block performed in the preoperative block room

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: QUADRUPLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: SSNB + PCB; Single shot US-guided suprascapular nerve block (SSNB) with 5 mL ropivacaine 0.5%, then single shot US-guided posterior cord block (PCB) with 10 ml ropivacaine 0.5%.	Procedure: Suprascapular Nerve Block + Posterior Cord Block; The patient lies supine with the head turned to the contralateral side to the block. Using a linear high-frequency ultrasound probe, the proximal suprascapular nerve is visualized before it turns toward the suprascapular notch. It is blocked using 5mL of ropivicaine 0.5%. The posterior cord is readily visualized when performing an infraclavicular brachial plexus block. It is blocked using 10mL of ropivicaine 0.5%.; Other Names: SSNB+PCB
ACTIVE_COMPARATOR: ISBPB; Single shot US-guided interscalene brachial plexus block (ISBPB) with 15 mL ropivacaine 0.5%.	Procedure: Interscalene Brachial Plexus Block; The patient lies supine with the head turned to the contralateral side to the block. Using a linear high-frequency ultrasound probe, the interscalene groove is visualized along with the roots of the brachial plexus. The block is performed with 15mL of ropivacaine 0.5%.; Other Names: ISPB

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dose of remifentanil in mcg/kg/h during the surgery period	The main criterion will be evaluating the dose of remifentanil per kg per hour of surgery needed intraoperatively to keep a NOL index below the threshold of 25.	Intraoperative from incision until wound dressing

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to awakening in minutes	Time to awakening in minutes.	Intraoperative
Time to extubation in minutes	Time to extubation in minutes.	Intraoperative
Duration of motor block in minutes strength	Duration of motor block in minutes, as measured by time to return of normal grip strength.	Postoperative for day 1 H24 24hours after surgery
NOL response after surgical incisions (area under curve)	NOL response after surgical incisions 1 (located 2 cm inferior and 1 cm medial to posterolateral corner of acromion) of the shoulder (by calculating the area under the curve of NOL for the 5 minutes following incision 1).	Intraoperative
NOL response after surgical incisions (area under curve)	NOL response after surgical incisions 2 (located slightly inferior to coracoid) of the shoulder (by calculating the area under the curve of NOL for the 5 minutes following incision 1).	Intraoperative
Total dose remifentanil in mcg	Total dose of remifentanil in mcg from incision until wound dressing	Intraoperative
Number of remifentanil boluses (n)	Number of remifentanil boluses administered to the patient from incision until wound dressing	Intraoperative
Desflurance consumption in ml	Intraoperative consumption of desflurane in mL	Intraoperative from incision until wound dressing
PACU pain scores on a scale from 0 to 10	PACU pain scores	From entrance in PACU until PACU discharge e.g. up to 3 hours after surgery maximum
Grip strength in mmHg	Grip strength before nerve blockade and prior to PACU discharge, as measured in mmHg by a pressure transducer connected to a 1000mL saline bag.	in PACU e.g. up to 3 hours after surgery maximum
Diaphragmatic paresis induced by the nerve block by ultrasound	Ipsilateral diaphragmatic excursion 30 minutes after block completion (normal, paradoxical or no movement).	30 minutes after nerve block and before general anesthesia and surgery, in awake patient
Patient dyspnea on a scale from 0 to 10	Patient dyspnea prior to PACU discharge on a scale from 0 to 10.	PACU e.g. up to 3 hours after surgery maximum
Time to readiness for discharge from PACU in minutes	Time to readiness for discharge from PACU = time in minutes to reach an Aldrete score at 9 for discharge	PACU e.g. up to 3 hours after surgery maximum
24h pain scores on a scale from 0 to 10 at rest	24h pain scores, H24	Postoperative at H24, 24 hours after surgery
48h pain scores on a scale from 0 to 10 at rest	48h pain scores	Postoperative at H48, 48 hours after surgery
24h pain scores on a scale from 0 to 10 during mobilization	24h pain scores during mobilization	Postoperative at H24, 24 hours after surgery
Per os postoperative (after PACU discharge) morphine equivalent consumption in mg at 8, 16, 24, 32, 40, 48 hs postoperatively	Per os opioid consumption in mg of equivalent morphine (every 8 hours by nurses or with a diary in patients with same day surgery).	Postoperative for 2 days 48 hours after surgery
Patient satisfaction on a scale from 0 to 100	Patient satisfaction at 24 hours on a scale from 0 to 100.	Postoperative at 24h, 24 hours after surgery

Collaborators and Investigators

• Sponsor: Ciusss de L'Est de l'Île de Montréal
• Investigators: Principal Investigator: Philippe Richebe, MD, PhD, CIUSSS de l'Est de Montreal

Study record dates

Study Major Dates

• Study Start (ACTUAL): September 15, 2019
• Primary Completion (ACTUAL): December 15, 2019
• Study Completion (ACTUAL): December 15, 2019

Study Registration Dates

• First Submitted: April 8, 2019
• First Submitted That Met QC Criteria: July 9, 2019
• First Posted (ACTUAL): July 10, 2019

Study Record Updates

• Last Update Posted (ACTUAL): October 8, 2021
• Last Update Submitted That Met QC Criteria: October 1, 2021
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Keywords: regional anesthesia; shoulder arthroscopy; interscalene brachial plexus block; NOL monitoring
• Other Study ID Numbers: 2019-1743

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No