Recent Modifications of the Nuss Procedure: The Pursuit of Safety During the Minimally Invasive Repair of Pectus Excavatum.

OBJECTIVE: To review standardized Nuss correction of pectus excavatum and vacuum bell treatment over the last 10 years. SUMMARY OF BACKGROUND DATA: In 2010, we reported 21 years of the Nuss procedure in 1215 patients. METHODS: Over the last 10 years, 2008-2018, we evaluated 1885 pectus excavatum patients. Surgery was indicated for well-defined objective criteria. A consistent operation was performed by 8 surgeons in 1034 patients, median 15 years, (range 6-46); 996 were primary, and 38 redo operations. Surgical patients' mean computed tomography index was 5.46. Mitral valve prolapse was present in 5.4%, Marfan syndrome in 1.1% and scoliosis in 29%. Vacuum bell treatment was introduced for 218 patients who did not meet surgical criteria or were averse to surgery. RESULTS: At primary operation, 1 bar was placed in 49.8%; 2 bars, 49.4%; and 3 bars, 0.7%. There were no deaths. Cardiac perforation occurred in 1 patient who had undergone previous cardiac surgery. Paraplegia after epidural catheter occurred once. Reoperation for bar displacement occurred in 1.8%, hemothorax in 0.3%, and wound infection in 2.9%; 1.4% required surgical drainage. Allergy to stainless steel was identified in 13.7%. A good anatomic outcome was always achieved at bar removal. Recurrence requiring reoperation occurred in 3 primary surgical patients. Two patients developed carinate overcorrection requiring reoperation. Vacuum bell treatment produced better results in younger and less severe cases. CONCLUSIONS: A standardized Nuss procedure was performed by multiple surgeons in 1034 patients with good overall safety and results in primary repairs. Vacuum bell treatment is useful.

Pectus repair after prior sternotomy: clinical practice review and practice recommendations based on a 2,200-patient database.

The minimally invasive repair of pectus excavatum (MIRPE) is widely accepted as a method of pectus excavatum (PE) repair. Repair is rarely performed in patients with a history of median sternotomy. A feared complication of this procedure is iatrogenic cardiac injury; the risk of injury in patients with prior sternotomy is especially high due to the development of post-surgical retrosternal adhesions, which obscures the "critical view" during MIRPE. A 14-center review reported the incidence to be as high as 7% after analyzing 75 patients with history of sternotomy who underwent MIRPE. Little literature exists on how to best prepare for MIRPE in patients with prior sternotomy. A review of the literature and a retrospective review of over 2,200 patients who underwent MIRPE at our institution was performed to analyze 9 patients who underwent MIRPE after prior sternotomy. Iatrogenic cardiac injury occurred in 2 patients. Given the infrequency in our experience and the low numbers reported in the literature, statistical conclusions cannot be drawn. However, prudent strategies based on this experience include thoracoscopy, routine sternal elevation, direct sub-xiphoid retrosternal dissection, coordination with cardio-thoracic surgeons, preparation for cardio-pulmonary bypass, and massive transfusion protocol availability to optimize surgical outcomes in patients undergoing MIRPE with a history of sternotomy.

Selective use of sternal elevation before substernal dissection in more than 2000 Nuss repairs at a single institution.

BACKGROUND/PURPOSE: Evaluate the safety of sternal elevation (SE) used selectively before creating the substernal tunnel during the Nuss procedure. METHODS: An IRB-approved (01-05-EX-0175-HOSP), single institution, retrospective review was performed (1/1/1997-11/20/2017). Primary and secondary Nuss repairs (i.e., previous Nuss, Ravitch, thoracotomy, or sternotomy) are included. SE use, cardiac injuries, and pectus bar infections are reported. Chi square and Fisher's exact test (FE) were used (critical p < .05). RESULTS: 2037 patients [(80% male; mean age 15.2 years (SD = 4.4, range 3-46); mean Haller index (HI) 5.3 (SD = 5.7, range 1.73-201)] underwent Nuss repair. SE was used before creating the substernal tunnel in 171 (8.4%): 160 (8.2%) of 1949 primary and 11 (12.5%) of 88 secondary repairs. SE use increased significantly [χ2(2) = 118.93; p < .001] over time and with increasing HI [χ2(3) = 59.9; p < .001]. No cardiac injuries occurred in primary repairs but two occurred in patients with previous sternotomy. Infection rates were not different with (2.9%) or without SE (1.8%) [χ2(1) =1.14; p = .285] and not higher with off-label VB (1.5%) versus other SE techniques (3.8%) [FE, p = .65)]. CONCLUSION: Selective use of sternal elevation before substernal dissection during the Nuss procedure is safe but may not prevent cardiac injuries in patients with previous sternotomy. Infection rates were not increased with SE. TYPE OF STUDY: Retrospective review. LEVEL OF EVIDENCE: IV.

Ten-year experience with staged management of pectus carinatum: Results and lessons learned.

INTRODUCTION: We report pectus carinatum management over a 10+year period. METHODS: Staged management, with initial bracing and operation for failure or special circumstances, was employed. A newer brace and a minimally invasive operation for PC (the Abramson procedure) were introduced during the study period. RESULTS: Of 695 consenting patients from 2008 to 2018, 265 (38%) were observed. Of 430 treated, 339 (79%) had bracing only; 65 (15%) underwent surgery without a trial of bracing, while 26(5%) underwent surgery after a failed attempt at bracing. Of 364 bracing patients, 144 (40%) were successful, 77 (21%) are ongoing, 25 (7%) failed, and 118 (32%) dropped out. Recurrence was noted in 17 (5%), an average 5.4 months later. Two (0.4%) overcorrected to pectus excavatum (PE). Successful patients experienced a 50% decrease in pressure of correction (POC) beginning one month after starting treatment. Brace failure patients did not. Reported compliance with brace utilization (hours/day) was similar. Surgery was required in 91 patients. Open operations were performed in 61 (67%), Abramson operations in 23 (25%), and Nuss procedure in 7 (8%) who developed excavatum over correction following bracing or who had mixed deformity, with excavatum one side of the sternum and carinatum on the other. Twenty-four (36%) of the surgeries for PC occurred after an attempt at bracing. All obtained good initial results by operation. No recurrence was noted after open operation and 3 (13%) after Abramson. Open complications included 1 (2%) infection. Abramson's operation required 11 (48%) revisions, 6 (26%) early bar removals, and had 3 (13%) infections. CONCLUSION: Brace treatment for PC can be guided by pressure of correction, which fell by more than half in successfully treated patients. POC did not fall in patients who failed. If POC does not fall, surgery should be considered. Open repair of Pectus Carinatum is generally successful, while the Abramson operation has a significant rate of complications with the implants currently available in the U.S. LEVELS OF EVIDENCE: Level III - Retrospective comparative study.

Twenty-one years of experience with minimally invasive repair of pectus excavatum by the Nuss procedure in 1215 patients.

OBJECTIVE: To review the technical improvements and changes in management that have occurred over 21 years, which have made the minimally invasive repair of pectus excavatum safer and more successful. SUMMARY BACKGROUND DATA: In 1997, we reported our 10-year experience with a new minimally invasive technique for surgical correction of pectus excavatum in 42 children. Since then, we have treated an additional 1173 patients, and in this report, we summarize the technical modifications which have made the repair safer and more successful. METHODS: From January 1987 to December 2008, we evaluated 2378 pectus excavatum patients. We established criteria for surgical intervention, and patients with a clinically and objectively severe deformity were offered surgical correction. The objective criteria used for surgical correction included computed tomography (CT) scans of the chest, resting pulmonary function studies (spirometry and/or plethysmography), and a cardiology evaluation which included echocardiogram and electrocardiogram. Surgery was indicated if the patients were symptomatic, had a severe pectus excavatum on a clinical basis and fulfilled two or more of the following: CT index greater than 3.25, evidence of cardiac or pulmonary compression on CT or echocardiogram, mitral valve prolapse, arrhythmia, or restrictive lung disease. Data regarding evaluation, treatment, and follow up have been prospectively recorded since 1994. Surgical repair was performed in 1215 (51%) of 2378 patients evaluated. Of these, 1123 were primary repairs, and 92 were redo operations. Bars have been removed from 854 patients; 790 after primary repair operations, and 64 after redo operations. RESULTS: The mean Haller CT index was 5.15 ± 2.32 (mean ± SD). Pulmonary function studies performed in 739 patients showed that FVC, FEV1, and FEF25-75 values were decreased by a mean of 15% below predicted value. Mitral valve prolapse was present in 18% (216) of 1215 patients and arrhythmias in 16% (194). Of patients who underwent surgery, 2.8% (35 patients) had genetically confirmed Marfan syndrome and an additional 17.8% (232 patients) had physical features suggestive of Marfan syndrome. Scoliosis was noted in 28% (340). At primary operation, 1 bar was placed in 69% (775 patients), 2 bars in 30% (338), and 3 bars in 0.4% (4). Complications decreased markedly over 21 years. In primary operation patients, the bar displacement rate requiring surgical repositioning decreased from 12% in the first decade to 1% in the second decade. Allergy to nickel was identified in 2.8% (35 patients) of whom 22 identified preoperatively received a titanium bar, 10 patients were treated successfully with prednisone and 3 required bar removal: 2 were switched to a titanium bar, and 1 required no further treatment. Wound infection occurred in 1.4% (17 patients), of whom 4 required surgical drainage (0.4% of the total). Hemothorax occurred in 0.6% (8 patients); 4 during the postoperative period and four occurred late. Postoperative pulmonary function testing has shown significant improvement. A good or excellent anatomic surgical outcome was achieved in 95.8% of patients at the time of bar removal. A fair result occurred in 1.4%, poor in 0.8%, and recurrence of sufficient severity to require reoperation occurred in 11 primary surgical patients (1.4%). Five patients (0.6%) had their bars removed elsewhere. In the 752 patients, more than 1 year post bar removal, the mean time from initial operation to last follow up was 1341 ± 28 days (SEM), and time from bar removal to last follow-up is 854 ± 51 days. Age at operation has shifted from a median age of 6 years (range 1-15) in the original report to 14 years (range 1-31). The minimally invasive procedure has been successfully performed in 253 adult patients aged 18 to 31 years of age. CONCLUSIONS: The minimally invasive repair of pectus excavatum has been performed safely and effectively in 1215 patients with a 95.8% good to excellent anatomic result in the primary repairs at our institution.

Development and validation of the Pectus Carinatum Body Image Quality of Life (PeCBI-QOL) questionnaire.

INTRODUCTION: While body image disturbances and quality of life in persons with pectus excavatum (PE) have been well documented, very little has been done to systematically measure and document the same in patients with pectus carinatum (PC). Because of this, the current study aimed to develop and validate an instrument to assess body image related quality of life in patients with PC and their parents. METHOD: Participants: Two waves of data collection took place. The development phase enrolled 78 PC patients and 76 matched parents. The validation phase enrolled 50 PC patients and 50 parents. Mean age at the initiation of treatment was 15.14 (SD = 2.54). Participants were mostly boys (85.9%) and White or Caucasian (89.7%). Instrument development, refinement, and validation: A group of 5 experts in chest wall deformities used existing measures of body image disturbances in PE, combined with the broader body image literature, to develop larger item pools for patients and their parents. Item analysis from this phase was used to remove poorly performing or statistically redundant items. In the validation phase, refined patient and parent instruments were examined using exploratory principal components factor analysis (EFA) with parallel analysis for factor retention, followed by Varimax rotation to identify a final factor solution. RESULTS/DISCUSSION: This development and refinement process yielded a final questionnaire for patients (18 items) and parents (15 items). The patient questionnaire includes four subscales, each with good internal consistency: Body Image Disturbance; Treatment Motivation/Engagement; Physical Limitations; and Social Disadvantage. The parent questionnaire includes 3 subscales: Body Image Disturbance; Treatment Motivation/Engagement; Physical Limitations. Patient and parent scales showed moderate correlations. Among patients with measures pre- and posttreatment, there was a significant improvement in overall PeCBI-QOL score. We demonstrate, in this study, that body image and related quality of life can be reliably and validly assessed with the PeCBI-QOL, which has implications for more comprehensively documenting the negative psychological and functional consequences of pectus carinatum. TYPE OF STUDY/LEVEL OF EVIDENCE: Study of diagnostic test/III.

The physiologic impact of pectus excavatum repair.

The adverse physiologic effects of pectus excavatum and subsequent resolution following correction have been a subject of controversy. There are numerous accounts of patients reporting subjective improvement in exercise tolerance after surgery, but studies showing clear and consistent objective data to corroborate this phenomenon physiologically have been elusive. This is partially due to a lack of consistent study methodologies but even more so due to a mere paucity of data. As experts in the repair of pectus excavatum, it is not uncommon for pediatric surgeons to operate on adult patients. For this reason, this review evaluates the contemporary literature to provide an understanding of the physiologic impact of repairing pectus excavatum on pediatric and adult patients separately.

Bleeding at Removal of Nuss Bar: Rare But Sometimes Significant.

BACKGROUND: Hemorrhage during Nuss bar removal is an uncommon but feared complication that can be life threatening if not controlled rapidly. This study aims to identify the incidence and sources of large volume hemorrhage, discuss successful management strategies, and provide patient care recommendations. METHODS: An IRB approved (#15-11-WC-0214), single institution retrospective chart review was performed on patients who underwent Nuss bar removal over a 15-year interval. Estimated blood loss (EBL), source of hemorrhage, management, and outcomes are reported. RESULTS: One thousand six hundred twenty-eight Nuss bar removal procedures were reviewed. EBL >150 mL occurred in 7 patients (0.43%), of whom 2 patients (0.12%) had EBL >2000 mL. Bleeding sources included: lateral soft tissue, lateral ectopic calcium, medial ectopic calcification, and an intercostal vessel. Most bleeding could be controlled with pressure and electrocautery. Only 2 patients (0.12%) required transfusion. One of these had bleeding from an intercostal vessel, and the other bled from a large vein in the medial calcified substernal tract. No patients sustained heart injury or died. CONCLUSION: Large volume hemorrhage after Nuss bar removal is rare, but may require blood transfusion, thoracoscopic exploration, or open exploration through thoracotomy or sternotomy. Nuss bar removal should be performed in centers capable of these interventions. After bar removal, a chest X-ray and a period of postoperative observation up to 6 hours may be beneficial to detect occult hemorrhage.

Cardiopulmonary Function in Thoracic Wall Deformities: What Do We Really Know?

Patients with pectus excavatum (PE) frequently present with complaints of exercise intolerance and cardiopulmonary symptoms. There continues to be controversy regarding the physiologic benefits of repair. The aim of this review is to summarize and discuss recent data regarding the cardiopulmonary effects of PE deformity and the evidence for improvement obtained after surgical repair including (1) a greater efficiency of breathing (chest wall mechanics), (2) improvement in pulmonary restrictive deficits, (3) an increase in cardiac chamber size and output, with improved cardiac strain and strain rate, and (4) improvement in exercise capacity.

Nonoperative management of pectus excavatum with vacuum bell therapy: A single center study.

PURPOSE: The purpose of this study was to determine variables predictive of an excellent correction using vacuum bell therapy for nonoperative treatment of pectus excavatum. METHODS: A single institution, retrospective evaluation (IRB 15-01-WC-0024) of variables associated with an excellent outcome in pectus excavatum patients treated with vacuum bell therapy was performed. An excellent correction was defined as a chest wall depth equal to the mean depth of a reference group of 30 male children without pectus excavatum. RESULTS: Over 4years (11/2012-11/2016) there were 180 patients enrolled with 115 available for analysis in the treatment group. The reference group had a mean chest wall depth of 0.51cm. An excellent correction (depth≤0.51cm) was achieved in 23 (20%) patients. Patient characteristics predictive of an excellent outcome included initial age≤11years (OR=3.3,p=.013), initial chest wall depth≤1.5cm (OR=4.6,p=.003), and chest wall flexibility (OR=14.8,p<.001). Patients that used the vacuum bell over 12 consecutive months were more likely to achieve an excellent correction (OR=3.1,p=.030). Follow-up was 4months to 4years (median 12months). CONCLUSION: Nonoperative management of pectus excavatum with vacuum bell therapy results in an excellent correction in a small percentage of patients. Variables predictive of an excellent outcome include age≤11years, chest wall depth≤1.5cm, chest wall flexibility, and vacuum bell use over 12 consecutive months. TYPE OF STUDY: Retrospective chart review. LEVEL OF EVIDENCE: Level III treatment study.

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.

Selective versus routine patch metal allergy testing to select bar material for the Nuss procedure in 932 patients over 10years.

AIM OF THE STUDY: The aim of the study was to determine the role of patch metal allergy testing to select bar material for the Nuss procedure. METHODS: An IRB-approved (11-04-WC-0098) single institution retrospective, cohort study comparing selective versus routine patch metal allergy testing to select stainless steel or titanium bars for Nuss repair was performed. In Cohort A (9/2004-1/2011), selective patch testing was performed based on clinical risk factors. In Cohort B (2/2011-9/2014), all patients were patch tested. The cohorts were compared for incidence of bar allergy and resultant premature bar loss. Risk factors for stainless steel allergy or positive patch test were evaluated. MAIN RESULTS: Cohort A had 628 patients with 63 (10.0%) selected for patch testing, while all 304 patients in Cohort B were tested. Over 10years, 15 (1.8%) of the 842 stainless steel Nuss repairs resulted in a bar allergy, and 5 had a negative preoperative patch test. The incidence of stainless steel bar allergy (1.8% vs 1.7%, p=0.57) and resultant bar loss (0.5% vs 1.3%, p=0.23) was not statistically different between cohorts. An allergic reaction to a stainless steel bar or a positive patch test was more common in females (OR=2.3, p<0.001) and patients with a personal (OR=24.8, p<0.001) or family history (OR=3.1, p<0.001) of metal sensitivity. CONCLUSION: Stainless steel bar allergies occur at a low incidence with either routine or selective patch metal allergy testing. If selective testing is performed, it is advisable in females and patients with a personal or family history of metal sensitivity. A negative preoperative patch metal allergy test does not preclude the possibility of a postoperative stainless steel bar allergy. LEVEL OF EVIDENCE: Level III Treatment Study and Study of Diagnostic Test.

Use of an Optical Scanning Device to Monitor the Progress of Noninvasive Treatments for Chest Wall Deformity: A Pilot Study.

BACKGROUND: The nonsurgical treatment of chest wall deformity by a vacuum bell or external brace is gradual, with correction taking place over months. Monitoring the progress of nonsurgical treatment of chest wall deformity has relied on the ancient methods of measuring the depth of the excavatum and the protrusion of the carinatum. Patients, who are often adolescent, may become discouraged and abandon treatment. METHODS: Optical scanning was utilized before and after the intervention to assess the effectiveness of treatment. The device measured the change in chest shape at each visit. In this pilot study, patients were included if they were willing to undergo scanning before and after treatment. Both surgical and nonsurgical treatment results were assessed. RESULTS: Scanning was successful in 7 patients. Optical scanning allowed a visually clear, precise assessment of treatment, whether by operation, vacuum bell (for pectus excavatum), or external compression brace (for pectus carinatum). Millimeter-scale differences were identified and presented graphically to patients and families. CONCLUSION: Optical scanning with the digital subtraction of images obtained months apart allows a comparison of chest shape before and after treatment. For nonsurgical, gradual methods, this allows the patient to more easily appreciate progress. We speculate that this will increase adherence to these methods in adolescent patients.

Pectus excavatum repair after sternotomy: the Chest Wall International Group experience with substernal Nuss bars.

OBJECTIVES: Patients with pectus excavatum (PE) after prior sternotomy for cardiac surgery present unique challenges for repair of PE. Open repairs have been recommended because of concerns about sternal adhesions and cardiac injury. We report a multi-institutional experience with repair utilizing substernal Nuss bars in this patient population. METHODS: Surgeons from the Chest Wall International Group were queried for experience and retrospective data on PE repair using sub-sternal Nuss bars in patients with a history of median sternotomy for cardiac surgery (November 2000 to August 2015). A descriptive analysis was performed. RESULTS: Data for 75 patients were available from 14 centres. The median age at PE repair was 9.5 years (interquartile range 10.9), and the median Haller index was 3.9 (interquartile range 1.43); 56% of the patients were men. The median time to PE repair was 6.4 years (interquartile range 7.886) after prior cardiac surgery. Twelve patients (16%) required resternotomy before support bar placement: 7 pre-emptively and 5 emergently. Sternal elevation before bar placement was used in 34 patients (45%) and thoracoscopy in 67 patients (89%). Standby with cardiopulmonary bypass was available at 9 centres (64%). Inadvertent cardiac injury occurred in 5 cases (7%) without mortality. CONCLUSIONS: Over a broad range of institutions, substernal Nuss bars were used in PE repair for patients with a history of sternotomy for cardiac surgery. Several technique modifications were reported and may have facilitated repair. Cardiac injury occurred in 7% of cases, and appropriate resources should be available in the event of complications. Prophylactic resternotomy was reported at a minority of centres.

Incorporating vacuum bell therapy into pectus excavatum treatment.

Vacuum bell therapy (VBT) was initially described over 100 years ago by Lange in 1910 but this treatment option has been substantially refined in the last decade largely due to the efforts, work, and collaboration of Dr. Frank-Martin Haecker with Eckart Klobe, the engineer who designed and produces the most commonly used vacuum bell today.

Nuss bar procedure: past, present and future.

Repair of pectus excavatum began at the beginning of the 20th century before endotracheal intubation was standard practice. Surgeons therefore developed techniques that corrected the deformity using an open procedure via the anterior chest wall. Initial techniques were unsatisfactory, but by the 1930s the partial rib resection and sternal osteotomy technique had been developed and was used in combination with external traction post-operatively to prevent the sternum from sinking back into the chest. In 1949, Ravitch recommended complete resection of the costal cartilages and complete mobilization of the sternum without external traction, and in 1961 Adkins and Blades introduced the concept of a substernal strut for sternal support. The wide resection resulted in a very rigid anterior chest wall, and in some instances, the development of asphyxiating chondrodystrophy. The primary care physicians therefore became reluctant to refer the patients for repair. In 1987, Nuss developed a minimally invasive technique that required no cartilage or sternal resection and relied only on internal bracing by means of a sub-sternal bar, which is inserted into the chest through two lateral thoracic incisions and guided across the mediastinum with the help of thoracoscopy. After publication of the procedure in 1998, it became widely accepted and a flood of new patients suddenly started to appear, which allowed for rapid improvements and modifications of the technique. New instruments were developed specifically for the procedure, complications were recognized, and the steps taken to prevent them included the development of a stabilizer and the use of pericostal sutures to prevent bar displacement. Various options were developed for sternal elevation prior to mediastinal dissection to prevent injury to the mediastinal structures, allergy testing was implemented, and pain management improved. The increased number of patients coming for repair permitted studies of cardiopulmonary function, which showed that patients with a severe degree of pectus excavatum have right- sided cardiac compression, decreased filling, and decreased stroke volume. The degree of pulmonary restriction and obstruction is related to the degree of deformity and degree of cardiac displacement into the left chest. The indications for surgical repair have been clearly outlined, the procedure has been standardized, and post-operative management protocols are now available. A review of our prospective database showed that 98% of patients have a good to excellent outcome. This review of the "Past" outlines the progression of the surgical techniques during the 20th century, the review of the "Present" outlines the important modifications and results of the closed technique, and the review of the "Future" outlines the various new options that are becoming available for the treatment of pectus excavatum.

Diminished pulmonary function in pectus excavatum: from denying the problem to finding the mechanism.

BACKGROUND: Recently, technical improvement in the ability to measure lung function and the severity of chest deformity have enabled progress in understanding the mechanism of limitations of lung function in pectus excavatum. METHODS: After establishing that most patients with pectus excavatum do have symptoms of exercise intolerance, easy fatigability, and shortness of breath with exertion, lung function has been evaluated by a variety of methods in different centers. Spirometry, plethysmography, exercise testing, oculo electronic plethysmography, and imaging methods have been used to assess lung function in pectus excavatum and its response to surgery. RESULTS: Not all patients with pectus excavatum have subnormal static pulmonary function testing; some have above-average values. However, in more than 1500 adult and pediatric surgical patients with anatomically severe pectus excavatum at a single center, the bell curve of FVC, FEV1, and FEF 25-75 is shifted to significantly lower values in pectus excavatum. The curve is shifted to higher values after operation by approximately one standard deviation. Previous work has demonstrated that patients with more anatomically severe pectus excavatum are more likely to have diminished PFT's. A mechanism for this effect is seen by oculo electronic plethysmography, which demonstrates that the depressed portion of the chest does not move on respiration. After Nuss procedure, the chest wall motion used to create suction to draw air into the lungs is indistinguishable from that of persons with a normal chest, and the intrathoracic volume is markedly increased. CONCLUSIONS: Pectus excavatum is accompanied in most patients by diminished static pulmonary function. Correction by Nuss procedure results in improvement in chest wall motion; this improvement in the thoracic bellows action is accompanied by improvement in pulmonary function testing.

Pectus excavatum from a pediatric surgeon's perspective.

Historically, pectus excavatum (PE) was reported to be congenital, but in our experience only 22% are noticed in the first decade of life. Thus far, genetic studies support an autosomal recessive heritability, which coincides with only 40% of our patients having some positive family history, but is also contradictory given a constant sex ratio of 4:1 in favor of males. This inconsistency may be explained by the effect of more than one pectus disease-associated allele. Once the deformity is noticed, it tends to progress slowly until puberty, when rapid progression is often seen. We recommend surgical repair at around 12-14 years of age since the chest wall is still typically flexible and because this allows us to keep the bar in place as the patient progresses through puberty which may help decrease growth-related recurrences. Patients with mild to moderate PE are treated with therapeutic deep breathing, posturing, and aerobic exercises, and in appropriately selected patients, the vacuum bell may also be offered. Patients that have severe symptomatic PE are offered Minimally Invasive Repair of Pectus Excavatum (MIRPE). The surgical technique in children is similar to that of adults, except for the higher forces involved that often necessitate sternal elevation and more involved stabilization strategies. Postoperative management includes pain control, deep breathing, and early ambulation. Exercise restriction is mandatory for the first six weeks with slow resumption of normal activity after 12 weeks.

Pulmonary function in pectus excavatum patients before repair with the Nuss procedure.

OBJECTIVES: Whether the origin of symptoms in pectus excavatum patients (Pex) is related to reduced pulmonary function or impaired cardiovascular performance is debatable. However, pulmonary function testing (PFT) is still part of the evaluation prior to surgical repair in Pex. The purpose of this study was to corroborate our hypothesis that the majority of Pex that qualified for surgery present preoperatively with normal or close to normal PFT. METHODS: After institutional review board approval, preoperative PFT data of Pex who underwent surgical repair were analyzed retrospectively: total lung capacity (TLC), vital capacity (VC), functional residual capacity, forced expiratory volume in 1 second (FEV1) and maximal expiratory flow at 25% of FVC (MEF25). RESULTS: 82 patients aged from 9 to 27 years (average, 15 years) underwent PFT. A restrictive pattern (VC<80%) was observed in 45%, an obstructive pattern (FEV1 < 75 %) in 35%, and a normal total lung capacity in 62% of the Pex. No significant correlation was noted between the increasing severity of the Haller index and the PFT. CONCLUSION: Adolescent Pex without relevant respiratory symptoms have nearly a normal lung function. We suggest to skip PFT from the routine preoperative assessment in asymptomatic Pex.

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

PURPOSE: An increase in postoperative infections after Nuss procedures led us to seek risks and review management. We report potential risk factors and make inferences for prevention of infections. METHODS: An IRB-approved retrospective chart review was used to evaluate demographic, clinical, surgical, and postoperative variables of patients operated on between 10/1/2005 and 6/30/2013. Those with postoperative infection were evaluated for infection characteristics, management, and outcomes with univariate analyses. RESULTS: Over this 8-year period (2005-2013), 3.5% (30) of 854 patients developed cellulitis or infection, significantly more than 1.5% (13) in our previous report of 863 patients, 1987-2005 (p=.007). The most frequent organism cultured was methicillin-sensitive Staphylococcus aureus. Patients who were given clindamycin preoperatively (5 of 26 patients) had higher infection rates than those who received cefazolin (25 of 828) (19% vs 3%, p<.001). Patients treated with a peri-incisional ON-Q (I-Flow, Kimberly-Clark, Irvine, CA) also had higher infection rates (8.3% vs 2.4%, p<.001). Of the 30 patients who developed an infection, eighteen (60%) with cellulitis or superficial infections did not require surgical treatment or early bar removal. The other twelve patients (40%) with deep hardware infections required an average of 2.2 operations (range 1-6), with 3 (25%) requiring removal of their stabilizer and 3 (25%) requiring early bar removal. None of these three patients experienced recurrence of pectus excavatum at 2 to 4 years of follow-up. CONCLUSION: Preoperative antibiotic selection and use of ON-Q's may influence infection rates after Nuss repair. Nuss bars could be preserved in 90% of all patients with an infection and even 75% of those with a deep hardware infection. Attempts to retain the bar when an infection occurs may help prevent pectus excavatum recurrence. Level of Evidence=III.