Forearm vs Brachial Plexus Blockade for Routine Hand and Wrist Surgery

University Health Network, Toronto

Status: Unknown

Conditions: Post-operative Pain Management

Treatments: Drug: Forearm Nerve Block; Drug: Brachial Plexus Block

Study type: Interventional

Funder types: Other

Identifiers

NCT03510559

17-6152-A

Details and patient eligibility

About

It is very common to perform nerve blocks for hand and wrist surgery. It allows the surgeon to perform the surgery and helps with pain control after surgery. This also means only light sedation is needed for the procedure instead of a general anesthetic, which speeds up recovery time.

There are 2 types of nerve blocks that can be done for hand and/or wrist surgery. The one that is done commonly now is where the whole arm is frozen with local anesthetic. Another option is to have a nerve block where only the arm from the elbow down is frozen. Either of these types of nerve blocks can be chosen to safely accomplish surgery of the hand or wrist. However, the best nerve block for hand and/or wrist surgery has not been decided yet.

In order to determine which block is best, the investigators will be looking at patient satisfaction with the experience, as well as the surgical conditions provided and overall safety.

It is thought that many patients may prefer the arm block below the elbow as it allows for greater mobility immediately following surgery, and the surgical conditions provided will be very similar to those of the full arm nerve block.

Full description

A randomized controlled trial involving adult patients undergoing surgery to the wrist and hand with centralized random allocation of patients to 2 groups: 1)Brachial plexus block and 2)Forearm block. The brachial plexus group will undergo a standard brachial plexus block. The forearm group will undergo a block of the proximal forearm targeting the radial sensory, ulnar, median and lateral antebrachial cutaneous nerves.

Group allocation will not be blinded from the treating physicians or patients due to methodological constraints. However, the research assistants performing follow-up assessments will be blinded.

Brachial plexus anesthesia provides a reliable sensorimotor block for upper extremity surgery. It is the current gold standard of anesthesia for surgery on the hand. A forearm block is an alternative anesthetic technique. As day surgery for hand procedures is less invasive and has fewer analgesic requirements, it may be that a forearm block, which allows for preservation of upper extremity function, is of benefit for these types of procedures. It is anticipated that patients may appreciate the forearm block as opposed to a brachial plexus block as they will have greater functionality post-operatively upon returning home. This contrasts with a brachial plexus block which causes a flaccid and insensate upper extremity lasting for many hours beyond the surgical procedure longer than the anticipated analgesic requirements which may be detrimental. Conversely, a forearm block may not provide sufficient anesthesia to create a dense motor blockade, which may result in unwanted intra-operative hand movements during surgery. This could pose a significant safety concern.

A forearm block has successfully been used as a primary anesthetic in patients undergoing hand surgery, although no information has been published about patient satisfaction and events related to patient safety.

The investigators aim to assess patient satisfaction, as well as overall efficacy and safety of the forearm blocks for hand and wrist surgery, as compared to the gold standard of brachial plexus blocks.

Enrollment: 160 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Consented, English-speaking, adult patients (age > 18)
• American Society of Anesthesiologists (ASA) classification I-III
• BMI ≤ 38 kg/m2 (quality of US imaging deteriorates significantly with obesity)
• Patients undergoing hand and/or wrist surgery (except wrist arthroscopy)

Exclusion criteria

• Previous upper extremity nerve block
• Contra-indication to nerve blocks e.g., infection, bleeding diathesis, allergy to local anesthetics
• Existing chronic pain disorders or history of use of ≥ 30mg morphine or equivalent per day
• Pre-existing neurological deficits or peripheral neuropathy involving the operative upper extremity
• Pregnancy
• Any significant psychiatric conditions that may affect patient assessment
• Inability to tolerate a forearm tourniquet
• Wrist arthroscopy surgery (requires upper arm tourniquet)
• Inability to speak or understand English without an interpreter present

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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160 participants in 2 patient groups

Brachial Plexus Block

Active Comparator group

Description:

It will be at the discretion of the anesthesiologist performing the block to choose a supraclavicular, infraclavicular or axillary block to achieve adequate surgical anesthesia of the operative arm. After sterile skin preparation with chlorhexidine, a linear array transducer probe is placed on the skin and the appropriate nerve structures are identified. Local anesthetics (30 mL of 50:50 mix of 0.5% bupivacaine and 2% lidocaine) will then be injected in 5 mL aliquots after negative aspiration for blood to achieve circumferential spread around the brachial plexus. Patients who have a failed brachial plexus block may undergo a rescue forearm block, and will be recorded as requiring supplemental local anesthetic.

Treatment:

Drug: Brachial Plexus Block

Forearm Nerve Block

Experimental group

Description:

Patients allocated to the forearm block will have it performed in the semi-setting position. After sterile skin preparation with chlorhexidine and infiltration with 1 mL of 1% lidocaine, a linear array transducer probe is placed at the distal forearm to visualize each peripheral nerve (radial, ulnar, median, and lateral antebrachial cutaneous). A 5 cm 22 G insulated needle is then used to target each nerve individually and infiltrate 7.5mL of the 50:50 mixture (similar to the brachial plexus block group) at each nerve to a total of 30mL.

Treatment:

Drug: Forearm Nerve Block