Magnetic Resonance Imaging of Interscalene Plexus Block

Disorder of Shoulder Clinical Trial

Official title:

Magnetic Resonance Imaging of Local Anesthetic Distribution: A Comparison of 5 and 15 Milliliters of Ropivacaine 0,75% for Ultrasound Guided Interscalene Plexus Blockade

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02175069
• Other study ID #: MR-ISB-1
• Status: Completed
• Phase: Phase 4
• First received: April 17, 2014
• Last updated: July 9, 2014
• Start date: December 2013
• Est. completion date: July 2014

Study information

• Verified date: July 2014
• Source: Paracelsus Medical University
• Contact: n/a
• Is FDA regulated: No
• Health authority: Austria: Federal Office for Safety in Health CareAustria: Agency for Health and Food Safety
• Study type: Interventional

Clinical Trial Summary

Interscalene plexus block is a widely used technique to provide anesthesia and analgesia for surgery at the upper extremity (shoulder and upper arm); it is standard-of-care in many institutions worldwide. Local anesthetic is being injected around the nerves supplying the arm (Plexus brachialis) at a specific location in the arm (between the scalenus muscles, thus called "interscalene plexus block"). The optimal volume of injection with regard to efficacy, safety and avoidance of untoward effects has been subject to intense debate for a long time. In spite of evidence that small volumes (between 5 and 7 mls) are effective for adequate postoperative analgesia, larger volumes up to 40 mls are still frequently used in many practices. However, with the use of such large doses, adverse events are known to occur with increased frequency, including paralysis of the diaphragm or spread of local anesthetic to the spinal cord.

This study is intended to help evaluate the effects of small or larger injection of local anesthetic around the brachial plexus, and to correlate the distribution with clinical efficacy, block duration, and possible side effects. It is a randomized, controlled, observer-blinded trial; patients undergoing shoulder or upper arm surgery will be randomly allocated to receive either 5mls or 20mls of local anesthetic for their interscalene plexus block. Magnetic resonance imaging will be performed immediately afterwards, followed by a series of neurological exams during the hospital stay. Test of lung function (spirometry) and ultrasound of the diaphragm will be used to evaluate effects of the block on respiratory mechanics.

Description:

Background: Interscalene plexus blockade (ISB) is frequently used during surgery of the upper limb. The use of ultrasound has significantly reduced time of onset and total volume of local anesthetics in comparison to nerve localization by stimulators. (1-4) The introduction of this technique has been correlated with decreased volumes of effective local anesthetics from 40 milliliters and more down to 10 milliliters and less.(3-4) As the injection site of ISB is located in close proximity to the anatomical structures of the spinal cord, spread of local anesthetics could potentially cause adverse events, including contralateral blockade and total spinal anesthesia. Case reports on these complications have been published previously. (5-11)In a recently published study we showed that the phenomenon of epidural spread can be reproduced in cadavers and seems to be positively correlated to injection-volumes exceeding 10 milliliters.(12) Moreover, we observed a trend towards cranial spread of the contrast agent in all investigated specimens along the course of the nerval roots towards the spinal cord. In another cadaveric study by Orebauch et al., cranial epidural spread was also detectable following injection of dye into the nerval roots of the brachial plexus.(13) Magnetic resonance imaging has not yet been used for visualization of the spread of local anaesthetics in ISB.

Given that ultrasound provides excellent visualization of target-structures in regional anesthesia and therefore enables physicians to place injection needles with enormous accuracy, the question arises whether there is a critical volume for local anesthetics increasing complications such as epidural spread and in consequence contralateral blockade.

The aim of this study is to confirm the findings of our cadaveric study in vivo and to show that the frequency of epidural spread correlates with injection of increased volumes of local anesthetics.

Primary endpoint: Spread of local anesthetics to the epidural space

Secondary endpoints:

• Contralateral epidural spread.

• Spread of local anesthetics to the phrenic nerve.

• Bed side spirometry and ultrasound investigation of the diaphragm in the PACU.

• Oxygen saturation in the PACU

• Self-reported block duration.

• Self reported pain scores for the first 24 postoperative hours

• Time to first analgesic consumption on demand.

• Total analgesic consumption (ropivacaine PCA).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: July 2014
• Est. primary completion date: July 2014
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• Age between 18 and 75 years

• Surgery of the shoulder (shoulder arthroscopy, open shoulder joint surgery, rotator cuff surgery, tendon transfer, shoulder arthroplasty, humerus fracture surgery)

• Patients willing to undergo magnetic resonance imaging prior to surgery

• Informed consent to participate in the study

• American Society of Anesthesiologists physical score I, II or III

Exclusion Criteria:

• Refusal to participate in the study

• Inability to understand the study protocol due to language barrier

• Serious cardiac or pulmonary disease such as decompensated heart failure, recent myocardial infarction (less than one month in the past), heart block greater than 2nd degree, obstructive sleep apnea and chronic obstructive lung disease greater than 2nd degree

• renal impairment with an calculated glomerular filtration rate below 60ml/min

• Hypersensitivity to ropivacaine or gadolinium or other contraindications against peripheral nerve blocks

• Chronic opioid usage greater than 15 mg oral morphine equivalents daily, the daily use of adjunctive pain medications (gabapentins, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors)

• Schizophrenia or bipolar disorders, uncontrolled anxiety, claustrophobia

• Peripheral neuropathy

• Hepatic or renal impairment

• Ongoing illicit drug or alcohol abuse

• Metal implants or other contraindications for magnetic resonance imaging

• Coagulopathy

• Participation in additional clinical trials within 4 weeks before screening

• Hearing impairment

• Pregnancy

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Disorder of Shoulder

Intervention

Procedure:
• Interscalene Nerve Block
ultrasound guided interscalene plexus block (UISB) immediately before magnetic resonance imaging of the neck.

Drug:
• Ropivacaine 0.75%, 20ml
20 ml of ropivacaine 0.75%
• Gadopentetate-Dimeglumine 0.0125 mmol
0.0125 mmol of gadopentetate-dimeglumine
• Gadopentetate-Dimeglumine 0.05 mmol
0.05 mmol of gadopentetate-dimeglumine
• Ropivacaine 0.75%, 5ml
5 ml of ropivacaine 0.75%

Procedure:
• Shoulder Surgery
As per individual requirement (patient-dependent)

Locations

Country	Name	City	State
Austria	Paracelsus Medical University, Department of Anesthesiology	Salzburg

Sponsors (1)

Lead Sponsor	Collaborator
Paracelsus Medical University

Country where clinical trial is conducted

Austria, 

References & Publications (13)

Cobcroft MD. Letter: Bilateral spread of analgesia with interscalene brachial plexus block. Anaesth Intensive Care. 1976 Feb;4(1):73. — View Citation

Dooley J, Fingerman M, Melton S, Klein SM. Contralateral local anesthetic spread from an outpatient interscalene catheter. Can J Anaesth. 2010 Oct;57(10):936-9. doi: 10.1007/s12630-010-9360-y. Epub 2010 Jul 23. — View Citation

Fredrickson MJ, Ball CM, Dalgleish AJ, Stewart AW, Short TG. A prospective randomized comparison of ultrasound and neurostimulation as needle end points for interscalene catheter placement. Anesth Analg. 2009 May;108(5):1695-700. doi: 10.1213/ane.0b013e31819c29b8. — View Citation

Fredrickson MJ, Ball CM, Dalgleish AJ. A prospective randomized comparison of ultrasound guidance versus neurostimulation for interscalene catheter placement. Reg Anesth Pain Med. 2009 Nov-Dec;34(6):590-4. — View Citation

Fredrickson MJ, Kilfoyle DH. Neurological complication analysis of 1000 ultrasound guided peripheral nerve blocks for elective orthopaedic surgery: a prospective study. Anaesthesia. 2009 Aug;64(8):836-44. doi: 10.1111/j.1365-2044.2009.05938.x. — View Citation

Fritsch G, Hudelmaier M, Danninger T, Brummett C, Bock M, McCoy M. Bilateral loss of neural function after interscalene plexus blockade may be caused by epidural spread of local anesthetics: a cadaveric study. Reg Anesth Pain Med. 2013 Jan-Feb;38(1):64-8. doi: 10.1097/AAP.0b013e318277a870. — View Citation

Gautier P, Vandepitte C, Ramquet C, DeCoopman M, Xu D, Hadzic A. The minimum effective anesthetic volume of 0.75% ropivacaine in ultrasound-guided interscalene brachial plexus block. Anesth Analg. 2011 Oct;113(4):951-5. doi: 10.1213/ANE.0b013e31822b876f. Epub 2011 Aug 4. — View Citation

Gologorsky E, Leanza RF. Contralateral anesthesia following interscalene block. Anesth Analg. 1992 Aug;75(2):311-2. — View Citation

Gomez RS, Mendes TC. Epidural anaesthesia as a complication of attempted brachial plexus blockade using the posterior approach. Anaesthesia. 2006 Jun;61(6):591-2. — View Citation

Kumar A, Battit GE, Froese AB, Long MC. Bilateral cervical and thoracic epidural blockade complicating interscalene brachial plexus block: report of two cases. Anesthesiology. 1971 Dec;35(6):650-2. — View Citation

Lombard TP, Couper JL. Bilateral spread of analgesia following interscalene brachial plexus block. Anesthesiology. 1983 May;58(5):472-3. — View Citation

Orebaugh SL, McFadden K, Skorupan H, Bigeleisen PE. Subepineurial injection in ultrasound-guided interscalene needle tip placement. Reg Anesth Pain Med. 2010 Sep-Oct;35(5):450-4. doi: 10.1097/AAP.0b013e3181e859f0. — View Citation

Vandepitte C, Gautier P, Xu D, Salviz EA, Hadzic A. Effective volume of ropivacaine 0.75% through a catheter required for interscalene brachial plexus blockade. Anesthesiology. 2013 Apr;118(4):863-7. doi: 10.1097/ALN.0b013e3182850dc7. — View Citation

* Note: There are 13 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Spread of local anesthetics to the epidural space	Spread of local anesthetics to the epidural space, as seen in the magnetic resonance imaging	10 minutes	Yes
Secondary	Contralateral epidural spread	as seen on MRI	10 min	Yes
Secondary	Spread of local anesthetics to the phrenic nerve	as seen on MRI	10 minutes	Yes
Secondary	Bed side spirometry and ultrasound investigation of the diaphragm in the PACU		24 hours	No
Secondary	Oxygen saturation in the PACU		2-6 hours	Yes
Secondary	Self-reported block duration		24 hours	No
Secondary	Self reported pain scores for the first 24 postoperative hours		24 hrs	No
Secondary	Time to first analgesic consumption on demand		24 hours	No
Secondary	Total analgesic consumption (ropivacaine PCA).		24 hours	No