Risk factors and management of Nuss bar infections in 1717 patients over 25 years

Chest Wall Dermatitis Patterns Following Thoracoscopic Intercostal Nerve Cryoablation for Surgical Correction of Pectus Excavatum

BACKGROUND

Intercostal nerve cryoablation (INC) has been shown to reduce postoperative pain and length of stay following surgical correction of pectus excavatum (SCOPE). Some patients have developed chest wall dermatological symptoms after INC that can be mistaken for metal allergy or infection. The purpose of this study is to report the symptoms, severity, incidence, and treatment of post-cryoablation dermatitis.

METHODS

A retrospective single institution review was performed for patients who underwent SCOPE with and without INC between June 2016 and March 2023 to assess for incidence of postoperative dermatological findings. Characteristics associated with these findings were evaluated.

RESULTS

During study period, 383 patients underwent SCOPE, 165 (43.1%) without INC and 218 (56.9%) with. Twenty-three (10.6%) patients who received INC developed exanthems characteristic of post-cryoablation dermatitis with two distinct phenotypes identified. No patients who underwent SCOPE without INC developed similar manifestations. Early dermatitis, characterized by a painless, erythematous, and blanching rash across the anterior thorax, was observed in 16 patients, presenting on median postoperative day 6.0 [IQR 6.0-8.5], with median time to resolution of 23.0 [IQR 12-71.0] days after symptom onset. Late dermatitis, characterized by hyperpigmentation spanning the anterior thorax, was observed in 7 patients, presenting on median postoperative day 129.0 [IQR 84.5-240.0], with median time to resolution of 114.0 [IQR 48.0-314.3] days.

CONCLUSION

This is the first report of dermatological manifestations following SCOPE with INC, a phenomenon of unknown etiology and no known long-term sequela. In our experience, it is self-resolving and lacks systemic symptoms suggesting observation alone is sufficient for resolution.

LEVEL OF EVIDENCE

IV.

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.

Substernal Extravascular Implantable Cardioverter-Defibrillator System Infections in Large Animals

The extravascular implantable cardioverter-defibrillator (EV ICD) with lead implantation in the substernal space may provide clinical advantages over transvenous and subcutaneous systems. This is the first reported examination of substernal infection in large animals implanted with the EV ICD system.The system was implanted in 13 large animals (canine, porcine, and ovine). The porcine were co-implanted with a transvenous cardiac resynchronization therapy with defibrillator (CRT-D) system. Infection was promoted through a cadence of immunosuppressive monitors and study interventions. The animals were monitored for clinical presentation of infection over 12-18 weeks, and cultures were collected to confirm infection. Treatment was bifurcated: 1) some infections were treated only with antibiotics ( "antibiotics only" ), whereas 2) some infections were treated with system removal and antibiotics ( "antibiotics + explant" ). Histopathology was conducted at the study closure.Five infections were confirmed over the course of the study, four of which involved infection of the EV ICD system and one infection of only the concomitantly implanted transvenous CRT-D system without EV ICD-related infection. Among the four EV ICD infections, two of two infections treated with antibiotics only did not resolve whereas two of two infections treated with antibiotics + explant resolved, as shown by histology. The transvenous CRT-D system infection progressed to septicemia and endocarditis, requiring early study discontinuation. No EV ICD-related infection progressed to blood stream infection, and the sternal bone did not become infected when infection was present in the substernal tissues.The study findings suggest that EV ICD-related infections are treatable with system removal and antibiotic therapy.

Associated risk factors for patients undergoing a unique or double Nuss bar placement for pectus excavatum

Background

Pectus excavatum is the most common chest wall deformity. Surgical correction via Nuss Procedure is a common approach. Patients with long-segment sternal depression require more than one Nuss bar to be inserted. Complications of Nuss procedure include surgical site infection and bar migration which may necessitate surgical re-intervention. There has been conflicting evidence regarding the safety profile of inserting two Nuss bars. We aim to specifically review the safety profile of two Nuss bar insertion and its complications.

Method

179 consecutive patients who had undergone Nuss procedure between November 2013 and November 2021 were identified. Data analysis was performed on patient's age at time of operation, gender, height, weight, Haller index, pre-existing medical conditions, indication for surgery, duration of operation, numbers of bars placed, length of stay, post-operative pneumothorax, bar migration, superficial and deep infections, need for surgical intervention and mortality.

Result

Patients receiving two Nuss bars were at a significantly higher risk of developing infective complications. Lower weight and Haller index increase the risk of surgical site infection and infection requiring re-operation in this group of patients. A cut-off of 50 kg has a specificity of 92.1% with a sensitivity of 68.8% in regards to surgical site infection.

Conclusion

Patients receiving two Nuss bars as a part of their Nuss procedure are at a significantly higher risk of developing infective complications. Selecting patients more than 50 kg to receive two Nuss bars appear to be a reasonable measure to reduce surgical site infection.

The Cross-Bar Technique for Pectus Excavatum Repair: A Key Element for Remodeling of the Entire Chest Wall

INTRODUCTION

 The multiple bar approach was developed to cover broader and heavier teenager/adult chest wall deformities. We designed the cross-bar technique to achieve remodeling of the entire chest wall. This study aimed to demonstrate the role of cross-bar and its benefits over the parallel bar.

MATERIALS AND METHODS

 The cross-bar technique involves placing two bars diagonally and then cross on the target. The primary purposes are to double the lifting forces by making two bars converge on a single target to lift inflexible heavy chest wall depressions or cover lower lateral areas. The results of the cross-bar and parallel bar are compared for the indications, postrepair outcomes, and complications.

RESULTS

 From 2016 to 2019, 247 patients who underwent multiple bar pectus excavatum (PE) repair were enrolled in the study: 157 with cross-bar and 90 with parallel bar. In the cross-bar group, 33% (51/157) received three bars in XI fashion to cover the upper depression. The cross-bar group was older (18.0 ± 6.1 vs. 15.7 ± 5.0), had higher depression index (1.9 ± 0.7 vs. 1.8 ± 0.3), and was less asymmetric (45% vs. 71%) than those in the parallel bar group. The overall complication rates were not different between the two groups (9.6% vs. 10%, p = 1.0), although the cross-bar group was more rigid and complex. There was no bar displacement or reoperation in both groups.

CONCLUSION

 The cross-bar technique is as safe and effective as the parallel-bar technique, even though it was selected to correct more complexities. The cross-bar technique could be a method for complex PE deformities for remodeling of the entire chest wall.

Nickel contamination after minimally-invasive repair of pectus excavatum persists after bar removal

BACKGROUND

Minimally-invasive repair of pectus excavatum (MIRPE) has been shown to be associated with high release of trace metals into patient's body. The aim of our study was to analyze the kinetics of metal contamination after MIRPE and after bar removal.

METHODS

We prospectively assessed nickel and chromium changes in blood, urine, and local tissue in patients undergoing MIRPE with stainless-steel bar(s). Baseline samples were taken prior to surgery, further samples were taken at six defined time points until 30 months after bar removal. Clinical symptoms were evaluated at the time of every sample collection.

RESULTS

28 patients were included (mean age 16.4 years). At four weeks after MIRPE and persisting up to bar removal, we found significantly elevated trace metal levels in blood and urine. Tissue nickel and chromium levels were significantly elevated at the time of bar removal. After bar removal, the concentration of trace metal in urine and the concentration of chromium in plasma decreased gradually. In contrast, nickel levels in blood further increased. Five patients showed irritative symptoms after MIRPE, all symptomatic patients had elevated metal levels.

CONCLUSIONS

Following MIRPE, we found a rapid systemic increase of nickel and chromium. Our data indicate that trace metal release could cause irritative symptoms. The prolonged elevated systemic nickel levels beyond bar removal necessitate further investigations of the long-term side effects of MIRPE.

Case series of metal allergy following Nuss procedure: Not only for stainless steel bars

BACKGROUND

Pectus excavatum is often managed with the Nuss procedure. Metal allergies to pectus bars occur in 5% of patients, though pre-operative testing is not generally routine.

OBJECTIVES

This study describes our experience with pre-operative metal allergy testing and post-operative allergic reactions to pectus bars.

METHODS

A retrospective study of patients who underwent a Nuss procedure at our institution from 2010-2020 was performed. Patients with documented "metal" allergy, defined by the need for and positive response to steroid treatment and the absence of infection, were included. Data on patient characteristics and clinical course were analyzed.

RESULTS

Five of 204 patients (2.5%) identified developed allergic metal reactions. Three of five patients developed allergic reactions to titanium bars, with two requiring early removal of the bar (< 2-3 years). Four patients required more than one course of steroids, and three required debridements for skin breakdown. All patients have maintained good surgical correction at one- and three-years post removal.

CONCLUSIONS

Pectus bar metal allergies occur with both stainless steel and titanium bars. Properly selected patients for pre-operative Finn^Ⓡ Chamber testing may reduce the overall incidence of stainless-steel allergies but may miss titanium bar allergies. Early recognition and treatment of bar allergies may salvage the bar and avoid premature removal.

The Nuss procedure for repair of pectus excavatum: 20 error traps and a culture of safety

In 1998, Donald Nuss changed the way the world thought about the surgical repair of pectus excavatum. The new operation adheres to sound orthopedic fundaments, but has a significantly higher learning curve than other operations in pediatric surgery. Variations in pectus excavatum type, severity, symmetry and chest wall pliability bring challenges. This article will detail common error traps and ways to avoid them when performing the Nuss procedure. As recent publications have shown, an operation done more than 50,000 times across the world may bring to light infrequent but devastating outcomes that may be preventable. The critical view of safety for pectus repair is discussed, as are areas where a culture of safety could optimize results on a larger scale. We will review potential opportunities to improve outcomes by identifying error traps in the preoperative, intraoperative, and postoperative care of patients undergoing the Nuss procedure.

Complications associated with the minimally invasive repair of pectus excavatum

The minimally invasive pectus excavatum repair (Nuss repair) is performed by pediatric general surgeons and pediatric and adult thoracic surgeons around the world. Complications related to pediatric surgical procedures are always a major concern for surgeons and their patients, and as with all surgery, especially pectus surgery, complications can be life-threatening. The purpose of this article is to discuss early and late complications of pectus excavatum surgery and potential preventive strategies to minimize them.

Multivariate analysis of risk factors for Nuss bar infections: A single center study

BACKGROUND/PURPOSE

Our previously published data suggested several risk factors for infection after the Nuss procedure. We aimed to further elucidate these findings.

METHODS

An IRB-approved (14-03-WC-0034), single institution, retrospective review was performed to evaluate the incidence of postoperative Nuss bar infections associated with seven variables. These were subjected to bivariate and multivariable analyses. A broad definition of infection was used including cellulitis, superficial infection with drainage, or deep infection occurring at any time postoperatively.

RESULTS

Over 7years (4/1/2009-7/31/2016), 25 (3.2%) of 781 patients developed a postoperative infection after primary Nuss repair. Multivariable analyses demonstrated an increased risk of infection with perioperative clindamycin versus cefazolin for all infections (AOR 3.72, p=.017), and specifically deep infections (AOR 5.72, p=.004). The risk of a superficial infection was increased when antibiotic infusion completed >60min prior to incision (AOR 10.4, p=.044) and with the use of peri-incisional subcutaneous catheters (OR 8.98, p=.008).

CONCLUSION

Following primary Nuss repair, the rate of deep bar infection increased with the use of perioperative clindamycin rather than cefazolin. The rate of superficial infection increased when perioperative antibiotic infusion was completed more than 60min prior to incision and with the use of peri-incisional subcutaneous catheters. Further studies are needed to better understand these findings.

TYPE OF STUDY

Retrospective chart review.

LEVEL OF EVIDENCE

Level III treatment study.

Trace metal release after minimally-invasive repair of pectus excavatum

Background

Several studies have shown a high incidence of metal allergy after minimally-invasive repair of pectus excavatum (MIRPE). We postulated that MIRPE is associated with a significant release of trace metal ions, possibly causing the allergic symptoms.

Methods

We evaluated the concentration with chromium, cobalt and nickel in blood, urine and tissue in patients prior to MIRPE and in patients who underwent an explantation of the stainless-steel bar(s) after three years.

Results

Our study group consisted of 20 patients (mean age 19 years) who had bar explantation and our control group included 20 patients (mean age 16 years) prior to MIRPE. At the time of bar removal we detected significantly elevated concentrations of chromium and nickel in the tissue compared to patients prior to the procedure (p<0,001). We also found a significant increase in the levels of chromium in urine and nickel in blood in patients three years post MIRPE (p<0,001). Four patients temporarily developed symptoms of metal allergy, all had elevated metal values in blood and urine at explantation.

Conclusions

Minimally-invasive repair of pectus excavatum can lead to a significant trace metal exposure.

Exaggerated Interventricular Dependence Among Patients With Pectus Excavatum: Combined Assessment With Cardiac MRI and Chest CT

OBJECTIVE

We sought to explore whether patients with pectus excavatum have exaggerated interventricular dependence and to evaluate the impact of the malformation severity (assessed on CT) on both anatomic and functional cardiac parameters (assessed on cardiac MRI).

SUBJECTS AND METHODS

The current study involved consecutive patients with a diagnosis of pectus excavatum who were referred to undergo cardiac MRI and chest CT to establish surgical candidacy or to define treatment strategies.

RESULTS

Sixty-two patients with pectus excavatum underwent cardiac MRI and chest CT. Fifty (81%) patients were male, and the median age was 17.5 years (range, 14.0-23.0 years). Forty-seven (76%) patients had evidence of right ventricular compression. The left ventricle showed a significantly decreased end-diastolic volume (inspiration vs expiration: 70.4 ± 11.6 vs 76.1 ± 13.7 mL/m², respectively; p = 0.01) and a significantly higher eccentricity index (1.52 ± 0.2 vs 1.20 ± 0.1, p < 0.0001) during inspiration than during expiration. The median respiratory-related septal excursion was 8.1% (interquartile range, 5.1-11.7%). Patients with pericardial effusion showed a significantly higher pectus excavatum severity index than patients without pericardial effusion (6.3 ± 3.4 vs 4.4 ± 1.3, respectively; p = 0.003). Patients with a relative septal excursion equal to or larger than 11.8% showed a significantly higher pectus excavatum severity index than patients with a relative septal excursion of less than 11.8% (6.3 ± 2.6 vs 4.7 ± 2.4, respectively; p = 0.05).

CONCLUSION

In this study, patients with pectus excavatum showed significant alterations of cardiac morphology and function that were related to the deformation severity and that manifest as an exaggerated interventricular dependence.