Ultrasound-Guided Percutaneous Cryoneurolysis for the Treatment of Pain following Traumatic Rib Fracture: A Randomized, Active-Controlled, Participant- and Observer-Masked Study

• Published in: Anesthesiology (Philadelphia) 2024-12
• Main Authors: Finneran, 4th, John J, Kobayashi, Leslie, Costantini, Todd W, Weaver, Jessica L, Berndtson, Allison E, Haines, Laura, Doucet, Jay J, Adams, Laura, Santorelli, Jarrett E, Lee, Jeanne, Trescot, Andrea M, Donohue, Michael C, Schaar, Adam, Ilfeld, Brian M
• Format: Article
• Language: English
• ISSN: 0003-3022; 1528-1175; 1528-1175
• DOI: 10.1097/ALN.0000000000005328

Traumatic rib fractures are associated with pain lasting weeks to months and a decreased ability to inspire deeply or cough to clear secretions. Ultrasound-guided percutaneous cryoneurolysis involves reversibly ablating peripheral nerve(s) using exceptionally low temperature with a transdermal probe, resulting in a prolonged nerve block with a duration measured in months. We hypothesized that cryoneurolysis would improve analgesia and inspired volume following rib fracture. Adults with 1-6 traumatic rib fractures were randomized to either active cryoneurolysis and a sham peripheral nerve block (PNB), or sham cryoneurolysis and active PNB in a participant/observer-masked fashion. The primary endpoint was the maximum inspired volume the day after the procedure as measured with an incentive spirometer. The day after the procedure, the unadjusted median [IQR] maximum inspired volume for participants who received cryoneurolysis (n=11) was 2,250 mL [1,500; 2,500] versus 1,300 mL [750; 2,500] for PNB (n=9, mean difference 496; 95%CI -428 to 1420; t-test P=0.269). When adjusted for covariates (e.g., baseline lung volume), the cryoneurolysis group had an estimated 793 mL greater mean volume than PNB (95%CI 273 to 1,312; ANCOVA P=0.005). Improvement from baseline in maximum inspired volume for cryoneurolysis was 1,000 mL [1,000; 1,375] versus 300 mL [0; 1,000] for PNB (t-test P=0.002). This was equivalent to an improvement over baseline of 100% [90%, 188%] for cryoneurolysis versus 30% [0%, 50%] for PNB (t-test P=0.003). Average daily pain scores were generally lower for the cryoneurolysis group throughout the first month. Total cumulative oxycodone equivalents were 5 mg [0, 13] for cryoneurolysis vs 45 mg [43, 135] for PNB (t-test P=0.013). Ultrasound-guided percutaneous cryoneurolysis improves maximum inspired lung volume while concurrently decreasing pain and opioid consumption after traumatic rib fracture. These results should be considered preliminary, requiring confirmation with a trial including a larger sample size.