Cryoanalgesia Increases Neuropathic Pain in Adults Undergoing Minimally Invasive Surgery: A 1-Year Follow-up of a Randomized Study.

Abstract

We previously reported results of a randomized trial comparing standard intercostal nerve block (SOC) with SOC plus cryoanalgesia (CRYO) in minimally invasive lung surgery. While no benefit was seen in early postoperative pain or opioid use, CRYO patients had significantly higher Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) scores at two weeks. We now report one-year follow-up outcomes using LANSS and Visual Analog Scale (VAS). This randomized trial (NCT05348447) enrolled adults undergoing minimally invasive thoracic surgery. SOC patients received intercostal nerve blocks (INB) with bupivacaine and lidocaine. CRYO patients received the same INB plus cryoablation of 5-6 intercostal nerves (120 seconds each). Patients were followed at 3, 6, and 12 months. LANSS scores ≥12 indicated neuropathic pain. Pain severity was assessed using VAS. Follow-up data were available for 76 patients at 3 months (36 SOC, 40 CRYO), 82 at 6 months (42 SOC, 40 CRYO), and 84 at 12 months (44 SOC, 40 CRYO). Median LANSS scores were higher in CRYO at all timepoints: 10 vs. 0.5 (P=0.003), 8 vs. 0 (P<0.001), and 4.5 vs. 0 (P<0.001). At 3, 6, and 12 months respectively, more CRYO patients had LANSS ≥12 (40% vs. 19%, 33% vs. 10%, 30% vs. 5%; P=0.031, 0.010, 0.002), and higher VAS scores were observed at 3 and 6 months (P=0.012, 0.028) but not at 12 months (P=0.168). Cryoanalgesia increased neuropathic pain incidence and severity through one year. Without early clinical benefit, its use in minimally invasive thoracic surgery warrants caution.