Anesthesia, Local, Phrenic Nerve Palsy on the Left, Phrenic Nerve Palsy on the Right, Phrenic Nerve Paralysis, Upper Extremity Injury
Conditions
Brief summary
One of the most frequently performed peripheral nerve blocks (the injection of local anesthetic near nerves to block sensation/ movement to a specific part of the body) is the interscalene brachial plexus block for upper extremity surgeries. This type of block can unmask underlying respiratory issues such as shortness of breath due to a well-known and typically insignificant side effect of temporary diaphragmatic paralysis. The nerve block may be able to use saline solution to wash out the local anesthetic and potentially reverse this respiratory side effect. Specifically, the goal of this study is to determine if the injection of saline through the nerve block catheter reverses blockade of the phrenic nerve supplying the diaphragm, without affecting the ability of the nerve block to provide pain control after surgery.
Interventions
PROCEDURENormal saline injected via interscalene nerve catheter
With the catheter covered, treatment group patients will receive a normal saline (NS) bolus regimen (30cc 0.9% NS) via their interscalene nerve block catheter.
OTHERPlacebo
With the catheter covered, placebo group patients will go through the same steps as the treatment group, but no solution will be injected into the interscalene nerve block catheter.
Sponsors
Stanford University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* All adult patients (18 years and over) scheduled for surgery requiring a continuous interscalene brachial plexus nerve block catheter as part of their anesthetic care.
Exclusion criteria
* Concomitant life-threatening injuries and other concomitant injuries causing significant pain * Pregnant * Any condition impairing patient's ability to consent to participation in study, and an existing condition contraindicating a nerve block, i.e. nerve injury, existing bleeding disorder, infection in the vicinity of the block, and patient refusal.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in forced vital capacity (FVC) | Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments) | Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment. |
| Change in peak expiratory flow (PEF) | Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments) | Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment. |
| Change in forced expiratory volume in 1 second (FEV1) | Before the nerve block placement, within 1 hour after the surgery, then in 5, 15, and 30 minutes after the saline injection/placebo (1 minute each for a total of 5 assessments) | Spirometry data will be collected using a digital spirometer before nerve block is placed, after surgery, and after receiving either the placebo or treatment. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Diaphragmatic excursion | Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (5 minutes each for a total of 3 assessments.) | Diaphragmatic excursion will be assessed via ultrasound before nerve block is placed, after surgery, and while receiving either the placebo or treatment. |
| Brachial plexus sensory and motor exam | Before nerve block is placed, within 1 hour after the surgery, and while receiving either the placebo or treatment (2 minutes each for a total of 3 assessments). | Brachial plexus sensory and motor exam changes will be assessed before nerve block is placed, after surgery, and while receiving either the placebo or treatment. |
| Pain scores | Pain scores will be assessed before nerve block is placed, within 1 hour after the surgery, while receiving either the placebo or treatment. (1 minute each for a total of 3 assessments) | The Numerical Pain Rating Scale is a subjective measure in which individuals rate their pain on an eleven-point numerical scale. The scale is composed of 0 (no pain at all) to 10 (worst imaginable pain). Pain scores will be assessed before nerve block is placed, after surgery, while receiving either the placebo or treatment. |
Countries
United States
Outcome results
None listed