The Use of Cryoanalgesia in Minimally Invasive Repair of Pectus Excavatum: Lessons Learned

Regional Anesthesia and Surgical Volume in Children Undergoing Nuss Repair: A Multicenter Review

INTRODUCTION

Regional anesthetic approach and surgical volume have been shown to outcomes in patients undergoing Nuss procedure for pectus excavatum. However, their independent relationship is not described. We investigated how regional anesthesia and surgical volume are associated with length of stay (LOS), postoperative opioid use, operating room utilization, and complications.

METHODS

This is a 9-center retrospective review of patients ≤21 ys after Nuss procedure for pectus excavatum (2016-2020). High-volume centers and surgeons defined as the upper-quartile for annual procedures. Outcomes were compared with mixed effects linear/logistic regression models with random intercepts by institution as appropriate. A single-center unadjusted analysis was performed of erector spinae catheter (ESC) utilization (due to nonuniform use; high-volume only at 1-center).

RESULTS

780 patients were included. Significant variation existed in anesthetic approach and volume. Cryoablation was independently associated with shorter LOS (-2.1 d; 95% confidence interval [CI]: -2.6,-1.7) and lower postoperative opioid utilization (-120 morphine milligram equivalents, 95% CI: -181, -58.1) but increased surgical time (+45 min; 95% CI: 30.3, 59.8). Individual surgeon volume was associated with decreased LOS (-0.3 d; 95% CI: -0.5, -0.01), though high-volume centers had increased complications (odds ratio 2.2; 95% CI: 1.1, 4.2). There was no association between anesthetic approach and surgical complications. Within the single center utilizing ESCs (n = 138), a shorter LOS (2 versus 3 d, P < 0.01) was observed compared to those not receiving an ESC (n = 19).

CONCLUSIONS

Analgesic approaches varied significantly across institutions and limited our ability to directly compare cryoablation and ESCs. On multivariate analysis, cryoablation was associated with decreased LOS and postoperative opioid use, irrespective of center and surgeon volume. ESCs were similarly associated with improved outcomes. Rigorous prospective comparison of ESCs and cryoablation is warranted.

Prediction Model for Outpatient Opioid Use Following the Minimally Invasive Repair of Pectus Excavatum

INTRODUCTION

To minimize unused outpatient opioids while providing adequate pain control, we sought to create a model to predict outpatient opioid use following the minimally invasive repair of pectus excavatum with cryoablation MIRPE-C.

METHODS

A retrospective review was conducted at a single center from May 2023 to January 2024 among patients <21 years who underwent MIPRE-C. Demographic and clinical data, including inpatient and outpatient opioid use were reviewed. Patients completed opioid use questionnaires at their first postoperative visit. Simple linear regression was employed to create a model for outpatient opioid use.

RESULTS

Sixty-eight patients underwent MIRPE-C: 84% were male (mean age of 15.2 ± 1.7 years, and median Haller index 4.2[IQR:3.7-5.7]). Daily mean inpatient opioid requirement and daily opioid doses were 0.3 ± 0.2 OME/day/kg and 2 ± 1.2 opioid doses/day. At the first outpatient follow-up visit, patients reported using a median of five 5-mg oxycodone tablets [IQR:1.6-10] for 5 days [IQR:2-7] with 22% of patients needing an opioid refill. On linear regression, inpatient opioid use had a significant relationship with the number of outpatient doses taken, while patient factors were not associated with outpatient opioid use. A simple equation for predicting opioid need based on best fit (R2 = 0.211) was developed: #OUTPATIENT OPIOID TABLETS = 3 TABLETS + (0.82 x #INPATIENT OPIOID RECIEVED).

CONCLUSION

The proposed outpatient opioid prescription model is simple to calculate and tailors the prescription to individual patient need. This model has the potential to provide effective pain control and avoid prescription refills, while minimizing over-prescription of opioids.

LEVEL OF EVIDENCE

Treatment study Level III.

Earlier preoperative percutaneous intercostal cryoanalgesia improves recovery after pectus excavatum surgery

BACKGROUND AND AIMS

Minimally invasive repair of pectus excavatum is associated with intense postoperative pain. We aimed to evaluate the effectiveness of percutaneous intercostal cryoanalgesia according to the different timing of its preoperative application. Outcome variables included pain, drug consumption, time to mobilization, and hospital length of stay.

METHODS

Retrospective data analyzed from a single pediatric institution, involving a series of consecutive patients who underwent pectus surgery. Group 1: 18 patients received thoracic epidural analgesia. Group 2: 11 patients underwent cryoanalgesia on the same day of surgery and epidural analgesia as a bridge to cryoanalgesia onset. Group 3: 13 patients underwent earlier preoperative intercostal cryoanalgesia with a median of 6 days (IQR 3-6) before surgery. All groups received rescue systemic analgesia.

RESULTS

Pain scores were similar among groups. The incidence of severe pain decreased in Group 3 versus Group 1 (38% vs 78%) (p<0.05). Ropivacaine epidural cumulative dose (mg/kg) decreased in Group 2 versus Group 1: 16 (IQR 12-23) versus 27 (IQR 22-35) (p<0.01). Cumulative oral morphine equivalent dose (mg/kg) decreased among groups: 12 (IQR 9.3-17), 8 (IQR 4.2-12), and 0.2 (IQR 0.0-0.3) (p<0.001) for Groups 1-3, respectively. Length of stay (days) also decreased among Groups 1-3, respectively: 7 (IQR 6-7), 6 (IQR 5-7), and 4 (IQR 4-5) (p<0.001).

CONCLUSIONS

This exploratory observational study suggests that the timing of cryoanalgesia may play a crucial role in its efficacy, with earlier placement being associated with improvements in pain, opioid utilization, and length of stay.

Effect of cryoablation in Nuss bar placement on opioid utilization and length of stay

BACKGROUND

Our institution recently transitioned from paravertebral nerve blocks (PVBs) to intercostal nerve cryoablation (INC) for pain control following minimally invasive repair of pectus excavatum (MIRPE). This study aimed to determine how INC affected the operative time, length of stay, complication rates, inpatient opioid use, and outpatient prescription of opioids at a single center.

METHODS

A retrospective review was performed at a single pediatric referral center of all patients who underwent MIRPE between 2018 and 2023. Patient demographics, operative details, and perioperative course were collected. The use of INC versus PVB was recorded. Univariate analyses were performed using Wilcoxon rank sum tests for continuous variables and chi-squared tests for categorical variables.

RESULTS

255 patients were included with a median age of 15 years, median BMI of 18.50 kg/m2, and median Haller index of 4.40. INC was utilized in 41% (105/255), and 59% (150/255) received PVB. The two groups did not differ significantly in BMI, Haller index, or complications, though the INC patients were older by 1 year (15.0 vs. 16.0, p = 0.034). INC was associated with an increased operative time (INC: 92 min vs. PVB: 67 min, p < 0.001), decreased length of stay (3 vs. 4 days, p =  < 0.001), more than twofold decrease in inpatient opioids per day (INC: 16 MME vs. PVB: 41 MME, p < 0.001), and a fourfold decrease in the amount of opioids prescribed at discharge (INC: 90 MME vs. PVB: 390 MME, p < 0.001).

CONCLUSION

INC after MIRPE significantly decreased both the inpatient opioid utilization and our outpatient prescribing practices while also decreasing our overall length of stay without increasing complications.

LEVEL OF EVIDENCE

Level III.

Opioid Prescriptions at Discharge After Minimally Invasive Repair of Pectus Excavatum Are Reduced With Cryoablation

BACKGROUND

The minimally invasive repair of pectus excavatum (MIRPE) is associated with significant postoperative pain and opioid use. The objective of this study was to determine the effect of intercostal nerve cryoablation (Cryo) on inpatient and post-hospital opioid prescription practices following MIPRE.

METHODS

A retrospective review at a single pediatric center was conducted of patients ≤21 years old who underwent MIRPE. Oral morphine equivalents (OME) of inpatient and discharge opioids were compared between Cryo and no-Cryo cohorts.

RESULTS

579 patients were identified (82.8% male, mean age 15.4 ± 2.0 years). Cryo was performed in 73.5% of patients. The total inpatient OME use was less in the Cryo group (0.89 ± 0.68 vs. 1.6 ± 0.5 OME/kg/day; p < 0.001). Patients who underwent Cryo were prescribed significantly less OME at discharge compared to the no-Cryo group (3.9 ± 1.7 vs. 10.0 ± 4.1 OME mg/kg, p < 0.001). There was no statistically significant difference in the proportion of patients who required an opioid prescription refill (Cryo 12.4% vs. no-Cryo 11.5%, p = 0.884) or were readmitted (Cryo 5.3% vs. no-Cryo 4.6%, p = 0.833).

CONCLUSION

Patients who underwent cryoablation during MIRPE were prescribed significantly less opioid at the time of discharge without increasing the need for opioid refills or hospital readmissions.

LEVEL OF EVIDENCE

Treatment study; Level III evidence.

Cryoanalgesia as the Essential Element of Enhanced Recovery after Surgery (ERAS) in Children Undergoing Thoracic Surgery-Scoping Review

This article aims to present cryoanalgesia as an inventive strategy for pain alleviation among pediatric patients. It underlines the tremendous need to align pain management with the principles of the enhanced recovery after surgery (ERAS) approach. The aim of the study was to review the patient outcomes of nerve cryoanalgesia during surgery reported with regard to ERAS in the literature. The literature search was performed using PubMed and Embase to identify articles on the use of cryoanalgesia in children. It excluded editorials, reviews, meta-analyses, and non-English articles. The analysis focused on the study methods, data analysis, patient selection, and patient follow-up. This review includes a total of 25 articles. Three of the articles report the results of cryoanalgesia implemented in ERAS protocol in children. The research outcome indicates shortened hospital stay, potential reduction in opioid dosage, and significant progress in physical rehabilitation. This paper also describes the first intraoperative utilization of intercostal nerve cryoanalgesia during the Nuss procedure in Poland, highlighting its effectiveness in pain management. Adding the cryoanalgesia procedure to multimodal analgesia protocol may facilitate the implementation of the ERAS protocol in pediatric patients.

Long-Term Sensory Function 3 years after Minimally Invasive Repair of Pectus Excavatum with Cryoablation

INTRODUCTION

Minimally invasive repair of pectus excavatum (MIRPE) with intercostal nerve cryoablation (Cryo) decreases length of hospitalization and opioid use, but long-term recovery of sensation has been poorly described. The purpose of this study was to quantify long-term hypoesthesia and neuropathic pain after MIRPE with Cryo.

METHODS

A prospective cohort study was conducted single-institution of patients ≤21 years who presented for bar removal. Consented patients underwent chest wall sensory testing and completed neuropathic pain screening. Chest wall hypoesthesia to cold, soft touch, and pinprick were measured as the percent of the treated anterior chest wall surface area (TACWSA); neuropathic pain was evaluated by questionnaire.

RESULTS

The study enrolled 47 patients; 87% male; median age 18.4 years. The median bar dwell time was 2.9 years. A median of 2 bars were placed; 80.9% were secured with pericostal sutures. At enrollment, 46.8% of patients had identifiable chest wall hypoesthesia. The mean percentage of TACWSA with hypoesthesia was 4.7 ± 9.3% (cold), 3.9 ± 7.7% (soft touch), and 5.9 ± 11.8% (pinprick). Hypoesthesia to cold was found in 0 dermatomes in 62%, 1 dermatome in 11%, 2 dermatomes in 17% and ≥3 dermatomes in 11%. T5 was the most common dermatome with hypoesthesia. Neuropathic symptoms were identified by 13% of patients; none required treatment.

CONCLUSION

In long-term follow up after MIRPE with Cryo, 46.8% of patients experienced some chest wall hypoesthesia; the average TACWSA with hypoesthesia was 4-6%. Hypoesthesia was mostly limited to 1-2 dermatomes, most commonly T5. Chronic symptomatic neuropathic pain was rare.

LEVEL OF EVIDENCE

Level IV.

Lessons Learned after 176 Patients Treated with a Standardized Procedure of Thoracoscopic Cryoanalgesia during Minimally Invasive Repair of Pectus Excavatum

BACKGROUND

Intrathoracic intercostal cryoanalgesia (Cryo) during minimally invasive repair of pectus excavatum (MIRPE) reports have been related to improved pain management, although its extent differs amongst studies. We aimed to report our experience using a standardized perioperative approach including Cryo during MIRPE, and compare our actual results with those of a previous thoracic epidural analgesia (TE) cohort. Lessons learned are summarized.

METHODS

Retrospective study including patients undergoing Cryo during MIRPE between October 2018 and May 2023. Results with a standardized perioperative approach were analyzed. We then compared our Cryo cohort with a previous cohort of 62 patients who underwent TE and MIRPE between 2013 and 2018. Continuous variables were reported as mean and standard deviation, and as median (interquartile range) for variables with non-uniform distribution.

RESULTS

We performed 176 Cryo during MIRPE (16.8 ± 4.6 years), with a mean postoperative length of stay (LOS) of 1.4 ± 0.8 days and a median total requirement of 7.5 (0.0; 15.0) oral morphine equivalents (OME) (mg). Patients with Cryo had a significantly lower mean LOS (1.4 ± 0.8 vs. 3.6 ± 1.0 days, p < 0.0001), and median total opioid requirement [7.5 (0.0; 15.0) vs. 77.4 (27.0; 115.5 OME (mg), p < 0.0001) compared to TE patients. Lessons learned included ensuring adequate contact of the cryoprobe with the target, proper exposition, and specialized multidisciplinary perioperative patient and family support, including psychology and physical therapy.

CONCLUSIONS

In this study, we reported lessons learned after performing a standardized protocol of perioperative care in patients undergoing Cryo during MIRPE. This protocol enabled the achievement of a short LOS and low postoperative opioid requirement.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

III.

Intercostal spinal nerve cryoablation for analgesia following pectus excavatum repair

Pectus excavatum is a common chest wall deformity, most often treated during adolescence, that presents a significant postoperative pain control challenge for pediatric surgeons following surgical correction. The purpose of this article is to review the technique and outcomes of intercostal spinal nerve cryoablation for postoperative analgesia following surgical correction of pectus excavatum. Contemporary and historic literature were reviewed. Findings are summarized to provide a concise synopsis of the benefits of intercostal spinal nerve cryoablation relative to alternative analgesic modalities, as well as advocate for more widespread inclusion of this technique into multimodal pain regimens.

Bilateral Lung Injury with Delayed Pneumothorax following Preoperative Cryoanalgesia for Pectus Excavatum Repair in a 13-year-old Boy

A 13-year-old male patient with marfanoid features and pectus excavatum with Haller index 4 and correction index of 38% underwent the Nuss procedure with cryoanalgesia 9 days prior, which transpired uneventfully. Preoperative spirometry was normal, and echocardiogram showed light aortic valve dilation. A month later, during a routine outpatient checkup, he referred middle abdominal pain, denying respiratory symptoms nor thoracic pain. He presented bilateral apical and right basal hypophonesis. Chest X-ray revealed bilateral pneumothorax and right pleural effusion. Consequently, the patient was admitted to the emergency room, and a chest computed tomography was ordered, reporting right apical blebs. Bilateral thoracoscopy was performed, and apexes were checked for pulmonary blebs to rule out primary pneumothorax. In the right chest, a wedge resection of a distorted area on the apex and pleuroabrasion were done. Four air leaking eschars were found when performing lung expansion under water as leaking test, corresponding to cryoanalgesia intercostal eschars, and subsequently closed by primary suture. In the left chest, there were no blebs. However, another four pleural lesions with intact pleura in the left lower lobe were also found. Postoperative course was uneventful and chest drains were removed 48 hours after surgery. He remains asymptomatic 21 months after discharge. Cryoanalgesia in pectus excavatum is spreading due to the improvement in postoperative pain control. However, some complications may occur.

Measurement and Thermodynamic Modeling of Energy Flux During Intercostal Nerve Cryoablation

INTRODUCTION

Intercostal nerve cryoablation is an increasingly adopted technique to decrease postoperative pain in patients undergoing surgical correction of pectus excavatum (SCOPE). Concerns regarding cryo-induced systemic hypothermia have been raised in pediatric patients; however, assessment of a cooled cryoprobe on body temperature has not been performed. We aimed to determine the energy flux from a maximally cooled cryoprobe and model the possible effects on a whole-body system.

METHODS

To directly measure energy flux, a maximally cooled cryoSPHERE probe (AtriCure, Inc, Mason, OH) was isolated in a well-mixed water bath at 37°C. Real-time temperatures were recorded. Three models were created to estimate intraoperative flux. Perioperative temperatures of 50 patients who received cryoablation during SCOPE were compared to 50 patients who did not receive cryoablation.

RESULTS

Direct calorimetry measured average energy flux of the maximally cooled cryoprobe to be 28 J/s. Thermodynamic modeling demonstrated the following: 1) The highest possible cryoprobe flux is less than estimated basal metabolic rate (BMR) of the average teenager undergoing SCOPE and 2) Flux in a best model of human tissue energy transfer using available literature is far less than the effects of BMR and insensible losses. Clinically, there were no significant differences in the minimum intraoperative, end procedure or first postoperative body temperatures for patients who received cryoablation and those who did not.

CONCLUSIONS

Cryoprobe flux is significantly fewer joules per second than BMR. Furthermore, in a clinical series there were no empiric differences in body temperature due to cryoablation employment, contradicting concerns regarding hypothermia secondary to cryoablation.

A Review of Slipping Rib Syndrome: Diagnostic and Treatment Updates to a Rare and Challenging Problem

Slipping rib syndrome (SRS) is a disorder that occurs when one or more of the eighth through tenth ribs become abnormally mobile. SRS is a poorly understood condition leading to a significant delay in diagnosis and therapeutic management. History and a physical exam are usually sufficient for a diagnosis of SRS. The utility of dynamic ultrasounds has also been studied as a useful diagnostic tool. Multiple surgical techniques for SRS have been described within the literature. Cartilage rib excision (CRE) has been the most common technique utilized. However, the literature has shown a high rate of recurrence and associated risks with the procedure. More recently, minimally invasive rib fixation and costal cartilage excision with vertical rib plating have been shown as successful and safe alternative techniques. This may be an effective, alternative approach to CRE in adult and pediatric populations with SRS.

Evaluation of Analgesic Practice Changes Following the Nuss Procedure in Pediatric Patients

INTRODUCTION

Pectus excavatum repair by the Nuss procedure results in severe postoperative pain. Regional blocks and intercostal nerve cryoablation (INC) have emerged as potential strategies to manage analgesia. This study compares pain-related outcomes following these perioperative interventions.

METHODS

We reviewed charts of patients <18 y who underwent the Nuss procedure at Duke Children's Hospital from July 2018 to June 2022. Patients were divided into three groups by analgesic strategy: no block, regional catheters, or INC, representing the chronologic change in our practice. The primary outcome was total and daily in-hospital opioid utilization measured by oral morphine equivalents (OMEs). Secondary outcomes included average daily pain scores, length of stay, opioid refills after discharge, and complications.

RESULTS

Twenty-one patients were included and analyzed: no block (n = 6), regional catheters (n = 7), and INC (n = 8). INC-treated patients required significantly lower total postoperative, in-hospital OMEs (64 ± 47 [mean ± standard deviation]) than those with no block (270 ± 217, P = 0.04) or those with regional catheters (273 ± 176, P = 0.03). INC was associated with longer average operative times (161 ± 36 min) than no block (105 ± 21 min, P = 0.005) or regional catheters (90 ± 11 min, P < 0.001). INC-treated patients had shorter hospital length of stays (median 68 h) than those with regional catheters (median 74 h, P = 0.006).

CONCLUSIONS

INC was associated with longer operative times but decreased in-hospital OMEs when compared to bilateral regional block catheters and multimodal analgesia alone.

Intercostal Nerve Cryoablation for Postoperative Pain Control in Pediatric Thoracic Surgery: A Scoping Review

Background: Cryoanalgesia uses the application of cold temperatures to temporarily disrupt peripheral sensory nerve function for pain control. This review outlines the principles of cryoablation, clinical applications, and clinical data for its use in pediatric thoracic surgery. Methods: A comprehensive PubMed search was performed using the principal terms and combinations of cryoablation, cryoanalgesia, Nuss, Nuss repair, pectus, pectus excavatum, thoracic surgery, thoracotomy, and chest wall. Pediatric articles were reviewed and included if relevant. Adult articles were reviewed for supporting information as needed. Reference lists of included articles were reviewed for possible additional sources. Discussion: The scientific and clinical principles of cryoablation are outlined, followed by a focused review of current clinical application and outcome data. Conclusion: Postoperative pain is a major challenge following thoracic surgery. Cryoanalgesia is emerging as an adjunct in pediatric thoracic surgery, particularly for the Nuss procedure or minimally invasive repair of pectus excavatum. It effectively controls pain, decreasing postoperative opioid use and hospital length of stay with few short-term complications. Although more long-term studies are needed, early evidence suggests there is reliable return of sensation to the chest wall and long-term neuropathic pain is rare.

Intercostal nerve cryoablation therapy for the repair of pectus excavatum: a systematic review

Introduction

The minimally invasive repair of pectus excavatum (PE) is a painful procedure that can result in long-term hospitalization and opioid use. To mitigate the length of stay and opioid consumption, many different analgesia strategies have been implemented. The aim of this study is to review the use and patient outcomes of intercostal nerve cryoablation (INC) during PE repair reported in the literature.

Methods

An unfunded literature search using PubMed identifying articles discussing INC during PE repair from 1946 to 1 July 2023 was performed. Articles were included if they discussed patient outcomes with INC use during PE repair. Articles were excluded if they were reviews/meta-analyses, editorials, or not available in English. Each article was reviewed for bias by analyzing the study methods, data analysis, patient selection, and patient follow-up. Articles comparing outcomes of INC were considered significant if p-value was <0.05.

Results

A total of 34 articles were included in this review that described INC use during pectus repair. Most supported a decreased hospital length of stay and opioid use with INC. Overall, INC was associated with fewer short-term and long-term complications. However, the researchers reported varied results of total hospital costs with the use of INC.

Conclusion

The review was limited by a paucity of prospective studies and low number of patients who received INC. Despite this, the present data support INC as a safe and effective analgesic strategy during the repair of PE.

Multicenter Assessment of Cryoanalgesia Use in Minimally Invasive Repair of Pectus Excavatum: A 20-center Retrospective Cohort Study

OBJECTIVE

To assess the clinical implications of cryoanalgesia for pain management in children undergoing minimally invasive repair of pectus excavatum (MIRPE).

BACKGROUND

MIRPE entails significant pain management challenges, often requiring high postoperative opioid use. Cryoanalgesia, which blocks pain signals by temporarily ablating intercostal nerves, has been recently utilized as an analgesic adjunct. We hypothesized that the use of cryoanalgesia during MIRPE would decrease postoperative opioid use and length of stay (LOS).

MATERIALS AND METHODS

A multicenter retrospective cohort study of 20 US children's hospitals was conducted of children (age below 18 years) undergoing MIRPE from January 1, 2014, to August 1, 2019. Differences in total postoperative, inpatient, oral morphine equivalents per kilogram, and 30-day LOS between patients who received cryoanalgesia versus those who did not were assessed using bivariate and multivariable analysis. P value <0.05 is considered significant.

RESULTS

Of 898 patients, 136 (15%) received cryoanalgesia. Groups were similar by age, sex, body mass index, comorbidities, and Haller index. Receipt of cryoanalgesia was associated with lower oral morphine equivalents per kilogram (risk ratio=0.43, 95% confidence interval: 0.33-0.57) and a shorter LOS (risk ratio=0.66, 95% confidence interval: 0.50-0.87). Complications were similar between groups (29.8% vs 22.1, P =0.07), including a similar rate of emergency department visit, readmission, and/or reoperation.

CONCLUSIONS

Use of cryoanalgesia during MIRPE appears to be effective in lowering postoperative opioid requirements and LOS without increasing complication rates. With the exception of preoperative gabapentin, other adjuncts appear to increase and/or be ineffective at reducing opioid utilization. Cryoanalgesia should be considered for patients undergoing this surgery.

Ultrasound-Guided Percutaneous Cryoanalgesia for Pectus Excavatum: When Should It be Applied?

INTRODUCTION

 The addition of ultrasound-guided percutaneous cryoanalgesia (PCr) for pain management after pectus excavatum (PE) surgery offers a new and advantageous approach. Our aim is to describe our experience with PCr applied on the same day, 24 hours, and 48 hours prior to PE surgery.

MATERIAL AND METHODS

 Prospective pilot study in patients undergoing ultrasound-guided PCr (2019-2022) was divided into three groups: PCr on the same day of surgery (PCrSD), PCr 24 hours before (PCr24), and PCr 48 hours before (PCr48). We describe the application of technique and data obtained by comparing the three groups.

RESULTS

 We present 42 patients (25 PCrSD, 11 PCr24, 6 PCr48). PCr24 had a shorter procedure duration than PCrSD (65.8 vs. 91.2 minute; p = 0.048). Related to analgesia, PCr24 and PCr48 showed lower opioid consumption than PCrSD in PCA volume (48.5 and 49.6 vs. 75.1 mL; p = 0.015) and PCA time (23.3 and 23.8 vs. 34.3 hours; p = 0.01). Degree of pain (VAS scale) on the day of surgery and on the second postoperative day was lower in PCr24 and PCr48 than in PCrSD (4 and 2 vs. 5; p = 0.012; 0 and 1 vs. 2; p = 0.01, respectively) as well as shorter hospital stay (3 and 3.5 vs. 5 days; p = 0.021). In addition, PCr24 showed lower opioid consumption and hospital stay than PCr48 (p > 0.05). The greatest savings in hospital costs were obtained in the PCr24 group.

CONCLUSION

 PCr48 and PCr24 prior to PE surgery offers lower opioid consumption, less pain and shorter hospital stay than PCrSD. PCr24 is comparable to PCr48, but seems to show advantages and simpler logistics for the patient and the hospital.

Development of a five point enhanced recovery protocol for pectus excavatum surgery

PURPOSE

We implemented and evaluated an Enhanced Recovery after Surgery (ERAS) protocol for Nuss procedures consisting of patient education, bowel management, pre/post-operative transitional pain service involvement, serratus anterior plane blocks and intercostal nerve cryoablation.

METHODS

A 5-point ERAS protocol was implemented using multiple plan-do-study-act (PDSA) cycles. Data was collected prospectively for patients in the full ERAS protocol and retrospectively for previous patients. The primary outcome was length of stay (LOS). Secondary outcomes were opioid consumption, pain scores, protocol compliance and patient satisfaction. The impact of PDSA cycles and the ERAS protocol was quantified using statistical process control charts and Mann Whitney U test.

RESULTS

A total of 53 patients were identified, 13 within the ERAS protocol and 40 prior to introduction. There was no difference in age, sex, or Haller index between the two cohorts. The median LOS was decreased by 3 days in the ERAS cohort (P = 0.00001). There was decreased opioid consumption on post-operative day 1 (1.47 vs 1.96 MME/kg, p = 0.009) and overall (3.12 vs 6.35 MME/kg, p = 0.0042) in the ERAS cohort. Median pain scores did not differ between cohorts. ERAS bundle element compliance was: education 92%, bowel management 100%, transitional pain involvement 100%, serratus block 100% and cryoablation 100%. The 1-month survey revealed that 92% of patients were satisfied with their experience.

CONCLUSION

Our results demonstrate significant reduction in LOS and a trend to decreasing opioid consumption in hospital following ERAS protocol implementation and support the further application of ERAS protocols in pediatrics.

LEVEL OF EVIDENCE

III - Retrospective comparative study.

Initial outcomes using cryoablation in surgical management of slipping rib syndrome

INTRODUCTION

Minimally invasive repair of pectus excavatum (MIRPE) and cartilaginous rib excision (CRE) for slipping rib syndrome (SRS) are painful procedures. Intercostal nerve cryoablation (Cryo) controls pain and decreases opioid use in MIRPE. Herein, we describe our experience with cryoablation in CRE.

METHODS

A retrospective chart review was performed of all patients undergoing CRE between 2018 and 2022. Data on demographics, clinical characteristics, operative details, and hospital course were collected.

RESULTS

A total of 98 patients underwent CRE: 68 CRE without cryo, 22 CRE + Cryo, and 8 combined MIRPE + CRE + Cryo. Ninety percent of patients underwent bioabsorbable rib plating. Patients were predominantly female (79%, 73%, 50% respectively) with median ages 17.6, 16.9, and 14.2 years respectively. CRE + Cryo patients used significantly less opioids in hospital (0.6 OME/kg [0.1,1.2]) compared to CRE without cryo (1.0 OME/kg [0.6,2.1]), p < 0.05. The median length of stay (LOS) in CRE + Cryo was 1 day [1,2] compared to 2 days in CRE without cryo [1,2], p = 0.09. MIRPE + CRE + Cryo patients used 0.6 OME/kg [0.2,8.0] with a 2 day [1,5.5] LOS. Ninety-one percent of Cryo patients had cryoablation of T9 and/or T10 intercostal nerves, with no documented abdominal wall laxity at median follow-up of 16 days. Cryo was applied extra-thoracically in CRE + cryo without thoracoscopy or lung isolation, while MIRPE + CRE + Cryo used a combination extra-/intra-thoracic cryoablation in with thoracoscopy.

CONCLUSION

Intercostal nerve cryoablation reduces opioid use and LOS in patients undergoing cartilaginous rib excision for slipping rib syndrome. Cryotherapy to as low as T10 did not result in abdominal wall laxity and can be applied extra-thoracically without the need for thoracoscopy. Ongoing prospective studies are required to assess the long-term outcomes.

LEVEL OF EVIDENCE

III.

Effectiveness of one minute per level intercostal nerve cryoablation for postoperative analgesia after surgical correction of pectus excavatum

PURPOSE

Intraoperative intercostal nerve cryoablation has emerged as a promising modality for postoperative analgesia following Surgical Correction of Pectus Excavatum (SCOPE). Most centers use two-minute cryoablation per level, although data from histologic and adult studies suggest the effectiveness of one-minute freezes. We aimed to describe our center's experience with one minute per level cryoablation.

METHODS

A retrospective single institution review of patients undergoing SCOPE was performed to compare patients pre- and post-intercostal nerve cryoablation implementation. Cryoablation was performed as one minute for each of the thoracic intercostal nerves T3-T7. Multivariable regression analyses were conducted to compare the outcomes and cost between pre- and post-implementation groups.

RESULTS

During the study period, 198 patients underwent SCOPE with one Nuss bar, receiving either intraoperative intercostal nerve cryoablation (Cryo, n = 100) or preoperative thoracic paravertebral catheters (NoCryo, n = 98). Surgical time was on average 9 min longer for the Cryo group (p<0.01). Median length of stay for the Cryo group was 3 days shorter compared to the NoCryo group (p<0.01). The Cryo group had a 19-fold and 5.6-fold reduction in average inpatient and total postoperative opioid usage, respectively (p<0.01). Total hospital costs were significantly lower in the Cryo group (p<0.01). Overall complication rate was not statistically significant different between the two groups.

CONCLUSIONS

Intraoperative one minute per level cryoablation is a potent approach to postoperative analgesia for SCOPE patients that led to a shorter hospital length of stay, lower hospital costs, and decreased opioid use compared to conventional analgesia at our institution. Pediatric surgeons performing correction of chest wall deformities should consider offering this technique.

Intercostal Nerve Cryoablation in Minimally Invasive Repair of Pectus Excavatum: Effect on Pulmonary Function

Introduction: Cryoablation of intercostal nerves is performed for pain control after minimally invasive repair of pectus excavatum (MIRPE). Cryoablation affects both sensory and motor neurons, resulting in temporary anesthesia to the chest wall and loss of intercostal motor function. The study objective is to determine the effect of cryoablation on incentive spirometry (IS) volumes, as a measure of pulmonary function, after MIRPE. Materials and Methods: A single-institution retrospective review of pediatric patients undergoing MIRPE was performed. All patients received a multimodal regimen (MMR) of analgesics postoperatively. Three groups were compared-cryoablation (CRYO), elastomeric pain pump (EPP), and MMR alone. The primary outcomes were postoperative IS volumes and IS volumes as a ratio of preoperative forced vital capacity (FVC). Secondary outcomes included pain scores, opioid use, length of stay (LOS), and infectious complications. Results: MIRPE was performed in 115 patients: 50 CRYO, 50 EPP, and 15 MMR alone. Groups were similar for demographics and pectus excavatum severity. Postoperative spirometry measurements were similar across groups: IS (CRYO 750 mL [500,961] versus EPP 750 mL [590,1019] versus MMR 696 mL [500,1037], P = .77); IS/FVC (CRYO 0.19 [0.14,0.26] versus EPP 0.20 [0.16,0.26] versus MMR 0.16 [0.15,0.24], P = .69). Although pain scores were also similar across groups, CRYO patients used less opioid (P < .05) and had shorter LOS (P < .05). Postoperative pneumonia was rare and similar across groups (P = 1.00). Conclusion: Intercostal nerve cryoablation during MIRPE does not adversely affect postoperative IS volumes or increase pneumonia rate, despite the temporary loss of motor innervation to intercostal muscles. Cryoablation provides effective pain control with less opioid use.

Cryoablation in 350 Nuss procedures: Evolution of hospital length of stay and opioid use

INTRODUCTION

Current studies show cryoablation decreases opioid requirements and lengths of stay (LOS) in patients undergoing the Nuss procedure for pectus excavatum. This study evaluated the relationship between cryoablation and clinical outcomes for the Nuss procedure.

METHODS

A retrospective single-center chart review was performed on patients undergoing the Nuss procedure with intercostal cryoablation from December 2017-August 2021. Demographics, hospital course, and postoperative complications were abstracted. To evaluate the evolution of outcomes over time, the earliest quarter (Q1) of cryoablation patients was compared to the last quarter (Q4).

RESULTS

Over 45 months, 350 Nuss procedures with cryoablation were performed. The mean age at operation was 15.7 ± 2.3 years with an average Haller Index of 5.4 ± 4.2. The mean operative time was 136 ± 40.5 minutes. On average, patients used 2.8 ± 2.5 OME/kg of opioid in hospital with a LOS of 2.7 ± 1.1 days. The Q4 patients were discharged 1.3 days earlier (p<0.05) than Q1 patients, with 80% of Q4 discharged by postoperative day #2 vs. 23% in Q1 (p<0.05). Q4 patients received 74% (p<0.05) less opioid in hospital and 21% (p<0.05) less on discharge. Within 90 days postoperatively, complication rates (chest tube placement, wound infection, readmission, neuropathic pain) were similar. Only two patients (0.6%) required reoperation for bar migration/slippage.

CONCLUSION

With increased experience, cryoablation for the Nuss procedure decreased opioid use by 74% and was associated with 80% of patients achieving early discharge. Major complication rates were not increased. Cryoablation can be successfully implemented as an effective method of postoperative analgesia.

LEVEL OF EVIDENCE

Level III.

Infectious complications of intercostal nerve cryoablation mediated by perioperative hypothermia during pediatric Nuss procedure

BACKGROUND

Intercostal nerve cryoablation (cryoanalgesia) is increasingly used for pain control in minimally invasive repair of pectus excavatum (MIRPE) by Nuss procedure. Cryoanalgesia may lower core body temperature and increase the risk of postoperative infectious complications. We investigated cryoanalgesia effects on infectious complications following MIRPE.

METHOD

We performed a retrospective review of patients undergoing MIRPE at our institution. Patients treated via multimodal analgesia with cryoanalgesia (Cryo) were compared to patients treated via multimodal analgesia +/- elastomeric pain pumps (Non-cryo). Core body and intraoperative minimum/maximum temperatures were recorded. Primary outcomes were wound infection and pneumonia; secondary outcome was length of stay (LOS). Fisher's Exact and Mann-Whitney U tests compared proportions and medians respectively, p-value ≤ 0.05 being significant.

RESULTS

80 patients were included, 35(43.7%) Cryo and 45(56.3%) Non-cryo. There were no significant differences in median [IQR] for age(15[13.3,16.0];p =0.86), number of bars inserted (2[1,2];p = 0.57), or operative time(123.5[98.3, 148.8]; p = 0.11) between the two groups. We found no significant differences in median [IQR] minimum temperature (35.4°C [35.0,35.8];p = 0.76), median change in intraoperative temperature (-0.13°C [-0.44,0.00];p = 0.94) or median recovery temperature (-1.10°C [-1.56,-0.65]; p = 0.59) between Cryo and Non-cryo. PACU temperature was significantly lower in the Cryo group, 36.4°C [36.2,36.6] p = 0.04. There were no postoperative wound infections in either group and no significant difference in incidence of postoperative pneumonia (8.57% versus 2.22%,p =  0.31) or median[IQR] for LOS (4[3,4];p = 0.57), between Cryo and Non-cryo patients.

CONCLUSION

Although cryoanalgesia for MIRPE resulted in lower core body temperature, there appears to be no significant difference between Cryo and Non-Cryo patients for LOS or infectious complications.

Early Postoperative Management of Lung Transplant Recipients

The early postoperative period after lung transplantation is a critical time. Prompt recognition and treatment of primary graft dysfunction can alter long-term allograft function. Cardiovascular, gastrointestinal, renal, and hematologic derangements are common and require close management to limit their negative sequelae.

Chest Pain and Dyspnea After a Minimally Invasive Repair of Pectus Excavatum

Although infrequent, damage to cardiovascular structures can occur during or following a minimally invasive repair of pectus excavatum. We present a case of right ventricular outflow tract compression caused by a displaced intrathoracic bar. Removal of the bar resulted in an improvement in symptoms and hemodynamics. (Level of Difficulty: Advanced.)

Managing Pain and Discomfort in Children with Cancer

PURPOSE OF REVIEW

Approximately 15,600 children are diagnosed with cancer annually. Many of these children have cancer-related pain that improves with cancer treatment, but some develop intractable pain from cancer progression or sequelae from treatment modalities. The purpose of this paper is to provide a critical evaluation of the literature relevant to pain management in children with cancer. We intend to emphasize important and up-to-date findings in pharmacology, interventional pain management, and complementary and alternative medicine.

RECENT FINDINGS

Alternative medications and routes of administration, complementary and alternative medicine techniques, and interventional pain procedures offer possible routes for a multi-pronged pediatric cancer pain management plan, although high-level data is often lacking. To improve pediatric cancer pain management, a multifaceted approach embracing the biopsychosocial model of pain is recommended, incorporating evidence-based pharmacology, complementary and alternative medicine techniques, and if needed, interventional pain procedures.

Percutaneous Cryoanalgesia: A New Strategy for Pain Management in Pectus Excavatum Surgery

INTRODUCTION

 In recent years, pain protocols for pectus excavatum (PE) have incorporated cryoanalgesia through thoracoscopic approach. Since 2019, ultrasound-guided percutaneous cryoanalgesia (PCr) has been applied at our institution, either on the same day as the Nuss procedure or 48 hours before surgery. We carried out a preliminary retrospective review of patients with PE in whom PCr prior to surgery was performed at our institution between 2019 and 2021.

MATERIALS AND METHODS

 Two groups were evaluated: PCr on the same day (PCrSD) and PCr 48 hours before surgery (PCr48). Despite PCr, patients were treated with "patient-controlled analgesia" (PCA) with opioids for at least 24 hours, switching to conventional intravenous analgesia and oral analgesia in the following days. Demographic, clinical-radiological variables, PCA opioid use, pain grade according to the visual analog scale (VAS), and length of stay (LOS) were compared between the groups. A total of 20 patients were included (12 with PCrSD and 8 with PCr48), without significant differences in demographics or clinical-radiological variables. The overall median time of PCr was 65 minutes (55-127), with no differences between the groups.

RESULTS

 PCr48 group presented with significantly lower median number of hours of continuous PCA (24 vs. 32 hours; p = 0.031), lower median number of rescue boluses (11 vs. 18; p = 0.042), lower median VAS in the early postoperative hours (2 vs. 5.5; p = 0.043), and lower median LOS (3.5 vs. 5 days).

CONCLUSION

 PCr performed 48 hours prior to surgery is more effective in terms of PCA requirements, VAS, and LOS when compared with cryoanalgesia on the same day.

Intercostal nerve cryoanalgesia in the treatment of pain in patients operated on by the modified Nuss method with the BackOnFeet application-a new strategy to improve outcomes

INTRODUCTION

The surgical Nuss correction of the funnel chest deformity is a painful procedure without an established consensus of pain relief methods. High doses and long duration of opioids requirements impedes the ERAS protocol introduction. The aim of this study was to evaluate the effectiveness of intraoperative intercostal nerve cryolysis in terms of pain management in relation to the routinely used multimodal analgesia in Poland. We also assessed the impact of using the proprietary "BackOnFeet" application on the quality of life of patients after surgery in relation to the ERAS protocol.

METHODS

The prospective, single-centre, non-randomised, before-after pilot study was conducted. Inclusion criteria were: funnel-shaped chest deformity, age range 11-18 years, first chest wall operation, agreement for the cryolysis and regional analgesia, no history of chronic painkillers use. The results of the "control group" (multimodal analgesia with regional analgesia commonly performed in Poland) were assessed. The interdisciplinary perioperative protocol with the "BackOnFeet" application and intraoperative intercostal nerve cryoanalgesia were introduced to the "intervention group".

RESULTS

Eighteen children were treated with standard protocol typical for Polish management and matched to eighteen patients who received cryoanalgesia and the "BackOnFeet" application access "intervention group". We noticed lower NRS points in first 24 h (p = 0.0048), shortening of time of opioid use (p = 0.0002), hospitalisation time (p = 0,01), improved quality of postoperative rehabilitation (p < 0.0001) and quality of life (p < 0.0001) among the "intervention group".

CONCLUSIONS

Intraoperative intercostal nerves cryolysis performed during the minimally invasive Nuss correction of funnel deformation in combination with bilateral is more effective in terms of acute pain management in relation to the routinely used multimodal analgesia in Poland, allowing for the shortening of time of opioid use, hospitalisation time, improved quality of postoperative rehabilitation and enabled ERAS protocol introduction. The use of the proprietary "BackOnFeet" application has a positive effect on the quality of life of patients after surgery.

Cryoanalgesia is Associated With Decreased Postoperative Opioid Use in Minimally Invasive Repair of Pectus Excavatum

BACKGROUND

Postoperative pain control is challenging after pectus excavatum repair. We aimed to understand the impact that cryoanalgesia had on opioid utilization and outcomes of pediatric patients undergoing minimally invasive repair of pectus excavatum (MIRPE).

METHODS

A single-center retrospective cohort study was conducted of all patients (< 18 y) who underwent MIRPE (2011-2019). Patients receiving cryoanalgesia were compared to those who did not. The primary outcome was total postoperative, inpatient, opioid use, measured as milligrams of oral morphine equivalents per kilogram (OME/kg). Univariate and multivariable analyses were performed.

RESULTS

Of 35 patients, 20 received cryoanalgesia (57%). Baseline characteristics were similar. Patients who received cryoanalgesia had a lower opioid requirement: median 2.3 mg OME/kg (IQR 1.2-3.1), versus 4.9 mg OME/kg (IQR 2.9-5.8), P < 0.001. Accounting for receipt of cryoanalgesia, epidural, and/or patient-controlled analgesia, cryoanalgesia was associated with a 3.3 mg OME/kg reduction in opioid use (P < 0.001). Median length of stay (LOS) was shorter in cryoanalgesia patients: 3.1 d (IQR 2.3-3.4), versus 5.1 d (IQR 4.3-5.4), P < 0.001. Complications within 90 d were similar between groups.

CONCLUSIONS

Cryoanalgesia is an effective adjunctive pain control modality for patients undergoing MIRPE. Use of cryoanalgesia was associated with lower postoperative opioid requirements and shorter LOS, without increased short-term complications, and should be considered for enhanced recovery after MIRPE.

Cryoanalgesia enhances recovery from minimally invasive repair of pectus excavatum resulting in reduced length of stay: A case-matched analysis of NSQIP-Pediatric patients

PURPOSE

Pain control is challenging after minimally invasive repair of pectus excavatum (MIRPE). Cryoanalgesia, which temporarily ablates peripheral nerves, improves pain control and may accelerate post-operative recovery. We hypothesized that cryoanalgesia would be associated with shorter length of stay (LOS) in children undergoing MIRPE.

METHODS

A matched cohort study was conducted of children (<18 years) who underwent MIRPE 2016-2018, using the National Surgical Quality Improvement Program-Pediatric database. Each patient who received cryoanalgesia during MIRPE was matched to four controls (no cryoanalgesia). Univariate and multilevel regression analyses were performed.

RESULTS

Thirty-five patients who received cryoanalgesia during MIRPE were matched to 140 controls. Patients who received cryoanalgesia had a LOS reduction with similar secondary outcomes (operative time, rates of complication, reoperation, and readmission). On multilevel regression adjusted for matched groups, cryoanalgesia was associated with a 1.3-day reduction in LOS (95% CI -1.8 to -0.8, p < 0.001). On sensitivity analysis excluding patients with complications, cryoanalgesia remained associated with a LOS reduction.

CONCLUSIONS

Cryoanalgesia is a promising adjunct in the care of pediatric patients undergoing MIRPE. Utilization is associated with a shorter LOS without an increase in operative time or complications. Cryoanalgesia should be considered for inclusion in enhanced recovery strategies for patients undergoing MIRPE.

Use of cryoanalgesia as a postoperative pain management for open pectus carinatum repair

PURPOSE

Cryoanalgesia has shown to have safety and efficacy as an adjunct post-operative pain management for Nuss procedure. One retrospective study reported its efficacy for analgesia with the Ravitch procedure, with improved pain scores and decreased length of stay versus thoracic epidural. We describe our initial experience with the use of cryoanalgesia for an open repair of pectus carinatum.

METHODS

We retrospectively reviewed the medical records of all patients who received cryoanalgesia during an open repair of pectus carinatum from 2016 to 2019 at our institution. We recorded pain scores at immediate post-operative and at 1-week follow up after hospital discharge. Length of stay and mean follow up time were also recorded.

RESULTS

Five pediatric patients underwent open repair of pectus carinatum with cryoanalgesia. The median postoperative length of stay (LOS) was 1 (range 1-2) day. Only one patient reported a non-zero pain score during their hospitalization, and this was a 3 out of 10 in the post-analgesia care unit. At 1-week postoperative visit, all patients had a pain score of 0. Median follow up was 1 (0.5-2) year. No patients developed neuralgia.

CONCLUSION

Cryoanalgesia is a safe and effective pain management strategy for pediatric patients undergoing open pectus carinatum repair.

A New Device for Thoracoscopic Cryoanalgesia in Pectus Excavatum Repair: Preliminary Single Center Experience

Introduction: Cryoanalgesia has been recently described as alternative technique for immediate and persistent pain treatment after pectus excavatum repair. Cryoanalgesia has the potentiality to reduce analgesic consumption and length of hospitalization. However, cryoanalgesia has not been standardized yet: the previous reports describe different techniques and systems and include only small series. In Europe, no reports on cryoanalgesia for pectus repair have been published so far. Materials and Methods: This is a prospective single center pilot study performed in adolescents undergoing minimally invasive pectus excavatum repair with a new cryoanalgesia system, using a probe designed specifically for thoracoscopy. This new double lumen probe has the theoretical advantage of freezing only in its tip, so reducing the risk of complications. Results: Seven patients undergoing pectus excavatum repair were treated with cryoanalgesia performed with the new probe. No complications of cryoanalgesia were reported. Total consumption of morphine during hospital stay was between 0.1 and 0.35 mg/kg, with no side effects reported. Mean time to discharge was 2.4 days. All patients reported a good pain control with a fair need of rescue medications for pain relief during the first week after discharge, and a very good pain control without need of rescue medications during following weeks. Conclusions: Our pilot study showed that the new cryoanalgesia device is efficacious in terms of pain control, hospital stay and resumption of post-operative activities. The cryoprobe designed allowed an easy and safe maneuver. A prospective trial is needed to better define the risks and benefits of this technique.