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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
The optimal volume of ropivacaine for pain relief after shoulder surgery
Scientific title
Optimising Analgesia after Shoulder Surgery: the optimum primary volume and dose of ropivacaine for continuous interscalene analgesia
Secondary ID [1] 259922 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Pain relief after shoulder surgery 4535 0
Condition category
Condition code
Anaesthesiology 4823 4823 0 0

Study type
Description of intervention(s) / exposure
Up down staircase method (sequential allocation of dose depending on the response of the previous patient) for determination of ED50 of both ropivacaine volume and concentration (administered by perineural injection) starting at 30 mL and 0.5%.
Once the ED95 for both the volume and concentration has been determined, this will be compared with ropivacaine 0.5% 30 mL.

This is a one-off injection in each patient.
Intervention code [1] 4294 0
Treatment: Drugs
Comparator / control treatment
30mL 0.5% ropivacaine as single injection via an interscalene catheter prior to shoulder surgery lasting 1 hour
Control group

Primary outcome [1] 5683 0
Presence or absence of pain in the PACU as determined by the patients primary recovery nurse - direct patient interrogation.
Timepoint [1] 5683 0
In post anaesthesia care unit (PACU) for 30 min. Outcome assessed by direct patient interrogation.
Primary outcome [2] 5918 0
Time to first onset of pain during first 24 hours
Timepoint [2] 5918 0
Once at 24 hours from treatment
Secondary outcome [1] 241582 0
Arm numbness/weakness (questionnaire)
Timepoint [1] 241582 0
Once during the first 24 hours on the afternoon of postoperative day 1.
Secondary outcome [2] 241590 0
Satisfaction (all with patient questionnaire)
Timepoint [2] 241590 0
First 24 hours postoperatively (once at 24 hours)
Secondary outcome [3] 241983 0
Grip strength using dynamometer
Timepoint [3] 241983 0
30 mins following emergence

Key inclusion criteria
Patients requiring continuous interscalene analgesia for shoulder surgery under the care of the three investigators
Minimum age
No limit
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Patient refusal of block. 2. Known neuropathy involving the shoulder undergoing surgery. 3. Known allergy to amide local anaesthetic drugs.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Initial invitation to participate in the study will occur in the surgeon's rooms. Approximately one week prior to surgery, patients will be contacted by a research assistant to provide further informed consent. Written informed consent will be obtained from all patients. Assignment of the patient to one of the 2 groups will be delivered in a sealed opaque envelope.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A computerised random number generator will be used to assign the patient to one of the 2 groups.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
A two part study:
First part is to determine the ED95 with respect to volume and concentration of ropivicaine for the primary interscalene catheter bolus dose. The up-down sequential allocation method will be used. Second part is to determine whether this dose has any significant difference in duration to that of ropivacaine 0.5% 30 mL.
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 1702 0
New Zealand
State/province [1] 1702 0

Funding & Sponsors
Funding source category [1] 4728 0
Commercial sector/Industry
Name [1] 4728 0
I-Flow International
Address [1] 4728 0
Lake Forrest, CA, USA 92630
Country [1] 4728 0
United States of America
Primary sponsor type
Dr Michael Fredrickson
Anaesthesia Institute
P O Box 109 199
Auckland 1149
New Zealand
Secondary sponsor category [1] 4269 0
Name [1] 4269 0
Address [1] 4269 0
Country [1] 4269 0

Ethics approval
Ethics application status
Ethics committee name [1] 6767 0
Northern Y Regional Ethics Committee
Ethics committee address [1] 6767 0
P O Box 1031
Waikato Mail Centre 3240
Ethics committee country [1] 6767 0
New Zealand
Date submitted for ethics approval [1] 6767 0
Approval date [1] 6767 0
Ethics approval number [1] 6767 0

Brief summary
If the primary hypothesis is confirmed, this study will provide evidence supporting the use of a lower primary bolus dose via the interscalene catheter prior to shoulder surgery. Increased exposure of the techniques may promote their uptake in this setting.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 29443 0
Address 29443 0
Country 29443 0
Phone 29443 0
Fax 29443 0
Email 29443 0
Contact person for public queries
Name 12690 0
Dr Michael Fredrickson
Address 12690 0
Anaesthesia Institute
P O Box 109 199
Auckland 1149
Country 12690 0
New Zealand
Phone 12690 0
+64 9 522 1117
Fax 12690 0
+64 9 522 1127
Email 12690 0
Contact person for scientific queries
Name 3618 0
Dr Michael Fredrickson
Address 3618 0
Anaesthesia Institute
P O Box 109 199
Auckland 1149
Country 3618 0
New Zealand
Phone 3618 0
+64 9 522 1117
Fax 3618 0
+64 9 522 1127
Email 3618 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary