None listed
Conditions
Brief summary
This study represents a continuation of our research into the use of ultrasound guided interscalene catheters (ISCs) for pain relief after shoulder surgery. Our previous research has shown that ultrasound guidance for the placement of these catheters confers several clinical benefits. A controversial issue that still remains is the optimum distance to blindly thread a non-stimulating catheter beyond needle tip once the needle position has been optimized under ultrasound guidance. Threading the catheter an arbitrary distance theoretically reduces the risk of catheter misplacement, but also increases the likelihood of the catheter tip being inadequately close to the target neural structures. We have traditionally advanced the catheter a distance of 2 cm beyond needle tip but other investigators advocate a distance of up to 5 cm. The purpose of this current study is to compare 3 interscalene catheter advancement distances beyond needle tip (5 cm, 2.5 cm, 0 cm) in patients having elective shoulder surgery. The null hypothesis that we will be testing is that there will be no difference in catheter effectiveness between the treatment groups as measured by the requirement for block supplementation in the recovery room. Secondary outcome measures will include postoperative pain on postoperative days 1 and 2, and catheter placement time.
Interventions
A single operator will place all interscalene catheters in the operating room. Intravenous midazolam 2 mg, alfentanil 0.5 mg and cephazolin 1 g will be administered 5 min prior to interscalene catheter placement. Catheters will be placed following administration of a superficial cervical plexus block. Superficial cervical plexus blocks will be performed by the infiltration of 5-10 mL 1% lidocaine with epinephrine (1/200,000) along the posterior border of the sternomastoid muscle midway between t
A single operator will place all interscalene catheters in the operating room. Intravenous midazolam 2 mg, alfentanil 0.5 mg and cephazolin 1 g will be administered 5 min prior to interscalene catheter placement. Catheters will be placed following administration of a superficial cervical plexus block. Superficial cervical plexus blocks will be performed by the infiltration of 5-10 mL 1% lidocaine with epinephrine (1/200,000) along the posterior border of the sternomastoid muscle midway between the cricoid cartilage and mastoid process. Using a random number generator, patients will be randomized to one of 3 groups: An insulated Tuohy needle) will be inserted at a point approximately 3 cm cephalad to the level of sixth cervical vertebra at the posterior border of sternomastoid muscle. The bevel of the needle will be orientated laterally throughout. A 10-5 MHz linear ultrasound probe will then be placed in the axial plane. The needle will be advanced superficially in a caudal and peripheral direction until tissue displacement is observed just lateral to the 2 most superficial elements of the brachial plexus. Saline 10 mL will be injected down the needle to observe for appropriate fluid spread adjacent to the brachial plexus trunks, and a non-stimulating catheter advanced either 5 or 2.5 cm past the needle tip. If ultrasound imaging proves difficult, a brief appropriate muscle twitch will be sought with a nerve stimulator set to 0.8 mA to confirm brachial plexus position. The skin will be prepared with tincture of benzoin, and then approximately 1 mL of medical cyanoacrylate will be applied to the catheter entry site. An epidural catheter-locking device will secure the catheter to the skin. General anesthesia will then be administered without prior motor or sensory testing. Following standard intravascular injection precautions, ropivacaine 0.75% 10m/lidocaine 1% 10 will be administered via the catheter. All 3 groups will receive their treatments just once only. Duration of treatments 48 hours
Sponsors
Dr Michael Fredrickson
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
All
Age
16 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Patients requiring continuous interscalene analgesia following elective shoulder surgery under the care of the Principal Investigator.
Exclusion criteria
Exclusion criteria will include patient refusal for interscalene block, severe respiratory disease or ischaemic heart disease, known neuropathy involving the arm undergoing surgery and known allergy to amide local anaesthetic drugs.
Outcome results
None listed