M. Pilkington1, C. M. Harbaugh2, R. B. Hirschl1, J. D. Geiger1, S. K. Gadepalli1 2University Of Michigan Medical School,Department Of Surgery,Ann Arbor, MI, USA 1University Of Michigan,Pediatric Surgery,Ann Arbor, MI, USA
Introduction: Intercostal nerve cryoablation is one component of the pain management armamentarium for post-thoracic surgery analgesia. It has been shown to reduce length of stay in the minimally invasive Nuss procedure but its role in the Modified Ravitch has not been explored. This study aimed to determine the effect of cryoanalgesia on length of stay, opioid use, and complications.
Methods: We performed a retrospective review of all pediatric patients (<21 years) undergoing a Modified Ravitch procedure between January 1, 2015 and July 31, 2018 at our center. Postoperative analgesia included intercostal cryoablation (IC; n = 9), thoracic epidural (TE; n = 19), or noninvasive analgesia alone (NI; n = 14) at the treating team’s discretion. Length of stay (LOS), complications, parenteral intraoperative opioids, inpatient analgesic use, and outpatient analgesic prescribing were collected. Opioids were converted to oral morphine equivalents per kilogram (OME/kg) for comparison. Chi-squared analysis was performed for categorical variables and Kruskal-Wallis H test was used for continuous variables.
Results: The groups had similar patient characteristics except age (IC median 15 years [IQR 14-16]; TE 16 [14-17]; NI 17.5 [17-18.8]; p < 0.001) and chest wall profile (dominant defect pectus carinatum versus excavatum; IC 44.4% carinatum, TE 15.8%, and NI 92.9%; p < 0.01). There was no difference in overall complication rate (IC 33.3%, TE 36.8%, NI 28.8%; p = 0.9). Length of stay, OR time, and opioid use are shown in the table below.
The use of cryotherapy reduced length of stay compared to patients with a thoracic epidural (4 days vs. 6 days, p < 0.01) and did not impact time in the OR (312 minutes vs. 335 minutes, p = 0.3) or operative time (261 minutes vs. 270 minutes, p = 0.4). Intraoperative parenteral opioid use was lowest in patients with a TE (0.53, p < 0.01) but did not differ between IC and NI (1.10 vs. 0.89; p = 0.2). The amount of opioid utilized as an inpatient did not differ (IC 1.48 OME/kg, TE 1.04 OME/kg, NI 1.87 OME/kg) nor did the number of outpatient opioids and refills prescribed (IC 3.34 OME/kg and 22.2%, TE 4.87 OME/kg and 15.8%, NI 3.63 OME/kg and 14.3%; p = 0.3 and p = 0.8).
Conclusion: This is the first study on the use of IC in patients who underwent the Modified Ravitch procedure. In pediatric patients that received invasive analgesia, IC reduced length of stay and provides analogous postoperative pain management with similar use of opioids as compared to patients with a thoracic epidural. The use of cryoanalgesia does not prolong length of time in the operating room, surgical time, nor increase complications compared to thoracic epidural.
