Sensory Recovery Following Intercostal Nerve Cryoablation for the Nuss Procedure.

Background: Intercostal nerve cryoablation (CRYO) during the Nuss procedure is effective for postoperative pain control, but little is known about patterns of sensory recovery following its use.

Methods: A single institution, prospective study of 121 patients undergoing Nuss bar placement with CRYO for pectus excavatum was conducted to assess sensory recovery. Patients received CRYO from T3-T8 and were followed at scheduled intervals. The primary outcome was time to return of normal chest wall sensation. Secondary outcomes included alterations in sensation, permanent numbness, and chronic neuropathic pain.

Results: Following CRYO, median time to normal sensation was 6.0 (range 1-12) months. This was achieved postoperatively by 14.9% at 3 months, 62.3% at 6 months, 85.1% at 9 months, and 98.3% at 12 months. 1.7% had a small area of persistent/permanent numbness in the lower central sternum. The most common altered sensation was hypersensitivity which occurred in 20.7%. Hypersensitivity began on average at 3.0 months postoperatively (range 0.25-6 months) and lasted a median of 1.0 (range 0.5-9) months. Only 5.8% described their altered sensation as painful, and all of these were successfully treated with gabapentin and/or capsaicin cream. All others resolved spontaneously. There were no cases of chronic neuropathic pain.

Conclusions: Sensory recovery following CRYO is a slow process that ultimately leads to normal sensation in virtually all patients by one year. Hypersensitivity is more common than expected but is rarely described as painful and always resolves. Permanent numbness can occur but is very rare and limited in scope.

Level of evidence: Therapeutic.

Level iv: