Preoperative and postoperative abnormalities in chest x-ray indices and in lung function in pectus deformities

STERNUM TOMOGRAPHIC EVALUATION IN PECTUS PATIENTS: ANALYSIS OF SAGITAL PARAMETERS

OBJECTIVE

To evaluate the sagittal tomographic reformatting of the sternum using unpublished radiographic parameters (indexes and angles), comparing them between the different types of pectus, and controls.

METHODS

44 patients with pectus deformities and controls underwent chest CT for analysis. The types of pectus were classified into: inferior pectus carinatum (IPC), superior (SPC) and lateral (LPC), and broad (BPE) and localized pectus excavatum (LPE). The following tomographic parameters were created and measured: (1) spine-manubrium-sternum index (SMS); (2) column-sternum index (CSI); (3) manubrium-sternal angle (MSA); (4) inferior manubrium angle (IMA); and (5) inferior sternum angle (ISA). Statistical analysis was performed between the pectus and control groups, and between the different types of pectus.

RESULTS

There was a significant difference between: a) pectus excavatum and pectus carinatum when analyzing the SMS, CSI, MSA and ISA indexes. b) LPE and control group for SMS and ISA. c) LPC and LPE, and LPC and BPE for SMS; d) BPE and LPC for CSI; e) IPC and LPE, and IPC and BPE for ISA; f) SPC and LPE, and SPC and BPE for IMA.

CONCLUSION

The radiographic indexes and angles created provided differentiation parameters between patients with different types of pectus, and between these and controls. Level of Evidence II, Prognostic Studies.

Clinical Evaluation of Exertional Dyspnea in Adult Pectus Excavatum Patients

Abstract:

Evaluation of patients with pectus excavatum has primarily been focused on the pediatric population who undergo surgical correction of sternal defects mainly for cosmetic reasons combined with exercise-limiting symptoms. The extent of cardiopulmonary improvement in this population based on cardiac imaging, pulmonary function testing, and cardiopulmonary exercise testing may be highly variable. There is no current consensus on the limitations of cardiopulmonary impairment or potential improvement from surgical repair in pediatric patients. Limited data has published in the medical literature on the evaluation of adults with pectus excavatum who may also present with a variety of clinical symptoms. Adult patients with exercise limitation and pectus excavatum may present with exertional dyspnea, chest discomfort, palpitations/tachycardia, exercise-induced wheezing, and use of bronchodilators for asthma-like symptoms. While numerous published review articles outline clinical evaluation and surgical treatment for younger patients, comprehensive evaluation for these adult patients has not been fully elucidated. There is no current consensus on the underlying cause of cardiopulmonary impairment in adult patients or their potential improvement from surgical repair. This review focuses on the recommended evaluation of adult patients to discern the potential cardiopulmonary limitations to exercise due to pectus excavatum, especially in physically fit adults such as active duty military personnel. Two illustrative cases are presented to describe the complexity of the evaluation of adult patients and potential need for surgical correction.

Surgical Correction of Pectus Excavatum Using a Rib Graft Strut Following Excision of Costal Cartilages

Background:

A number of techniques are described for correction of pectus excavatum (PE). This article describes the experience with an innovative procedure which combines features from the Ravitch and Nuss procedures without using prosthetic material.

Methods:

This cross-sectional study included 12 cases of PE from January 2000 to March 2017 managed by excision of deformed costal cartilages and support to the thoracic cage using an autologous free rib graft as a strut. Indication for surgery was Haller's Index above 3.2 with or without respiratory distress. Noncontrast computed tomography scans were done at 6 months after surgery to document the position of the strut and to see the final correction and new Haller's Index, respectively.

Results:

The male-to-female ratio was 2:1. Preoperative Haller's Index in all cases was >3.2 (range 3.25–14). The average age at surgery was 5 years and 8 months (range: 7 months–15 years). Mean duration of hospital stay was 11 days (range 5–16 days).The 11^th rib was used commonly although in two cases, the 10^th rib was used as the 11^th rib was considered relatively short. Pericardial effusion requiring strut removal was seen in one case; in another case, removal of the rib was needed because of nonhealing of a delayed dehisced surgical wound. Others had an uneventful postoperative period. The mean postoperative Haller's Index was 2.75 (range 2.0–7).

Conclusion:

This modified procedure using an autologous rib strut is technically feasible and reproducible even with limited facilities and gives excellent results.

Quantification of pectus excavatum: Anatomic indices

Pectus excavatum is the most common chest wall deformity in children. The central portion of the chest is displaced posteriorly relative to the remainder of the anterior chest wall. Quantification of defect severity can be performed with multiple imaging modalities or external thoracic measures, but is most commonly quantified by the Haller Index (HI) or Pectus Correction Index (PCI). These two measures provide a measure of the chest based on cross sectional imaging, most commonly CT scans, allowing for standard comparison and definitions of pectus defects. The purpose of this article is to describe the creation, calculation, and limitations of the methods quantifying pectus defects.

The effect on cardiopulmonary function after thoracoplasty in pectus carinatum: a systematic literature review

OBJECTIVES

Creating an aesthetically appealing result using thoracoplasty, especially when correcting extensive deformities, but only causing low morbidity, is challenging. The frequency of thoracoplasties in cases of pectus carinatum (PC) has increased due to improved experience and modified surgical techniques, resulting in low morbidity and low complication rates. The indications for surgical treatment are still controversial and, in most cases, remain aesthetic or psychological rather than physiological. However, whether cardiopulmonary function changes after surgical repair remains a matter of controversy. We sought to investigate and shed light on published knowledge regarding this question.

METHODS

We searched MEDLINE and PubMed databases, using various defined search phrases and inclusion criteria, to identify articles on pre- and postoperative cardiopulmonary evaluation and outcomes.

RESULTS

Six studies met the inclusion criteria: 5 studies evaluated patients with PC for cardiopulmonary outcomes after chest wall surgery and 1 did so following conservative compression treatment. In these studies, surgical and conservative correction of PC did not reduce absolute lung volumes and spirometric measurements and consequently had no pathogenic effect on cardiopulmonary function.

CONCLUSIONS

The results of this systematic review suggest that surgical correction of PC has no symptomatic pathogenic effect on cardiopulmonary function. The results, however, revealed both heterogeneity in the examinations used and inconsistent methods within each study. Further prospective trials with a stronger methodological design are necessary to objectively confirm that surgical correction of PC does not impair cardiopulmonary function.

Morphometric analysis of variation in the ribs with age and sex

Rib cage morphology changes with age and sex are expected to affect thoracic injury mechanisms and tolerance, particularly for vulnerable populations such as pediatrics and the elderly. The size and shape variation of the external geometry of the ribs was characterized for males and females aged 0-100 years. Computed tomography (CT) scans from 339 subjects were analyzed to collect between 2700 and 10 400 homologous landmarks from each rib. Rib landmarks were analyzed using the geometric morphometric technique known as Procrustes superimposition. Age- and sex-specific functions of 3D rib morphology were produced representing the combined size and shape variation and the isolated shape variation. Statistically significant changes in the size and shape variation (P < 0.0001) and shape variation (P < 0.0053) of all 24 ribs were found to occur with age in males and females. Rib geometry, location, and orientation varied according to the rib level. From birth through adolescence, the rib cage experienced an increase in size, a decrease in thoracic kyphosis, and inferior rotation of the ribs relative to the spine within the sagittal plane. From young adulthood into elderly age, the rib cage experienced increased thoracic kyphosis and superior rotation of the ribs relative to the spine within the sagittal plane. The increased roundedness of the rib cage and horizontal angling of the ribs relative to the spine with age influences the biomechanical response of the thorax. With the plane of the rib oriented more horizontally, loading applied in the anterior-posterior direction will result in increased deformation within the plane of the rib and an increased risk for rib fractures. Thus, morphological changes may be a contributing factor to the increased incidence of rib fractures in the elderly. The morphological functions derived in this study capture substantially more information on thoracic skeleton morphology variation with age and sex than is currently available in the literature. The developed models of rib cage anatomy can be used to study age and sex variations in thoracic injury patterns due to motor vehicle crashes or falls, and clinically relevant changes due to chronic obstructive pulmonary disease or other diseases evidenced by structural and anatomic changes to the chest.

Variation of the Anthropometric Index for pectus excavatum relative to age, race, and sex

OBJECTIVES

To determine possible variations in the Anthropometric Index for pectus excavatum relative to age, race, and sex in individuals free of thoracic wall deformities.

METHODS

Between 2002 and 2012, 166 individuals with morphologically normal thoracic walls consented to have their chests and the perimeter of the lower third of the thorax measured according to the Anthropometric Index for pectus excavatum. The participant characteristics are presented (114 men and 52 women; 118 Caucasians and 48 people of African descent).

RESULTS

Measurements of the Anthropometric Index for pectus excavatum were statistically significantly different between men and women (11-40 years old); however, no significant difference was found between Caucasians and people of African descent. For men, the index measurements were not significantly different across all of the age groups. For women, the index measurements were significantly lower for individuals aged 3 to 10 years old than for individuals aged 11 to 20 years old and 21 to 40 years old; however, no such difference was observed between women aged 11 to 20 years old and those aged 21 to 40 years old.

CONCLUSION

In the sample, significant differences were observed between women aged 11 to 40 years old and the other age groups; however, there was no difference between Caucasian and people of African descent.

Symmetrical excessive pectus excavatum in children

OBJECTIVES

The indications for repair of pectus excavatum are controversial. We present our surgical results in children with severe pectus excavatum.

METHODS

27 children aged 6-15-years were included in the study. Pulmonary function tests and chest measurements were performed pre- and postoperatively. Deformed cartilages were resected subperichondrially, and a Kirchner wire was used to support the chest cage; it was removed 5 days after the operation. Fourteen children with restricted pulmonary function were considered to have excessive pectus excavatum.

RESULTS

3 patients had asthma-like symptoms that resolved postoperatively. None suffered chest pain postoperatively. Postoperative hospital stay was 7.1 days. Only minor complications occurred postoperatively. The mean pectus severity index was 0.27 ± 0.2 preoperatively and 0.41 ± 0.1 postoperatively (p < 0.05). For children with restricted pulmonary function, it was 0.17 ± 0.3 preoperatively and 0.38 ± 0.2 postoperatively (p < 0.05). Mean percentage of predicted forced expiratory volume in 1 s changed significantly from 79.2% ± 17.8% preoperatively to 83.6% ± 12.2% by the 3rd postoperative month. For children with a pectus severity index <0.2, it changed from 68.5% ± 13.2% preoperatively to 82.3% ± 13.4%. Pulmonary restriction correlated with a worse pectus severity index (r = 0.8). After 6 and 13 months, a minor decrease in pulmonary function was noted. Significant increases in right and left ventricular function occurred in cases of severe deformity.

CONCLUSIONS

Surgery is recommended not only for cosmetic reasons but also to increase cardiorespiratory functional capacity and alleviate symptoms. Kirchner wires can be used safely.

Effects of the Nuss procedure on chest wall kinematics in adolescents with pectus excavatum

No data are available on the effects of the Nuss procedure on volumes of chest wall compartments (the upper rib cage, lower rib cage and abdomen) in adolescents with pectus excavatum. We used optoelectronic plethysmography to provide a quantitative description of chest wall kinematics before and 6 months after the Nuss procedure at rest and during maximal voluntary ventilation in 13 subjects with pectus excavatum. An average 11% increase in chest wall volume was accommodated within the upper rib cage (p=0.0001) and to a lesser extent within the abdomen and lower rib cage. Tidal volumes did not significantly change during the study. The repair effect on chest wall kinematics did not correlate with the Haller index of deformity at baseline. Six months of the Nuss procedure do increase chest wall volume without affecting chest wall displacement and rib cage configuration.

Chest wall kinematics in young subjects with Pectus excavatum

Quantifying chest wall kinematics and rib cage distortion during ventilatory effort in subjects with Pectus excavatum (PE) has yet to be defined. We studied 24 patients: 19 during maximal voluntary ventilation (MVV) and 5 during MVV and cycling exercise (CE). By optoelectronic plethysmography (OEP) we assessed operational volumes in upper rib cage, lower rib cage and abdomen. Ten age-matched healthy subjects served as controls. Patients exhibited mild restrictive lung defect. During MVV end-inspiratory and end-expiratory volumes of chest wall compartments increased progressively in controls, whereas most patients avoided dynamic hyperinflation by setting operational volumes at values lower than controls. Mild rib cage distortion was found in three patients at rest, but neither in patients nor in controls did MVV or CE consistently affect coordinated motion of the rib cage. Rib cage displacement was not correlated with a CT-scan severity index. Conclusions, mild rib cage distortion rarely occurs in PE patients with mild restrictive defect. OEP contributes to clinical evaluation of PE patients.

Cardiopulmonary response following surgical repair of pectus excavatum in adult patients

OBJECTIVE

Severe pectus excavatum are common in adult patients, often causing psychological complaints and physiological impairments. Although lung function at rest may minimally deteriorate after surgical correction, it remains unclear if surgery improves exercise capacity. The objective of present study is to assess whether the surgical repair of pectus excavatum in adults would improve exercise tolerance.

METHODS

A prospective study was performed to compare pulmonary and cardiovascular function at rest and at maximal exercise, before, and at 1 year after pectus excavatum repair.

RESULTS

From December 2005 to May 2009, 120 adult patients underwent pectus excavatum repair. Of these patients, 70 (nine women, 61 men) underwent thorough preoperative, 6-, and 12-month postoperative assessments, and were included in the present study. Age ranged from 18 to 62 years (mean 27 years). The pectus index (Haller index) was 4.5 ± 1.1. Lung function tests at rest were within the normal range, whereas maximal oxygen uptake (peak VO₂) was only 77 ± 2% of the predicted value. At 1-year follow-up, the pectus excavatum repair was associated with minor changes in lung function tests and significant increase (p=0.0005) in VO₂ (87 ± 2% of the predicted value). Postoperative O₂ pulse increase at maximal exercise suggested that aerobic capacity improvement was the result of better cardiovascular adaptation at maximal workload.

CONCLUSION

These results demonstrate sustained improvement in exercise cardiopulmonary function at 1-year follow-up of pectus excavatum surgical repair in adult patients.

Pectus carinatum

Pectus carinatum or keel chest is a spectrum of progressive inborn anomalies of the anterior chest wall, named after the keel (carina) of ancient Roman ships. It defines a wide spectrum of inborn protrusion anomalies of the sternum and/or the adjacent costal cartilages. Pectus carinatum is often associated with various conditions, notably Marfan disease, homocystinuria, prune belly, Morquio syndrome, osteogenesis imperfecta, Noonan syndrome, and mitral valve prolapse. Treatment of pectus carinatum by nonsurgical methods such as exercise and casting has not been worthwhile, whereas surgical management is simple and successful.

Comparison of Haller index values calculated with chest radiographs versus CT for pectus excavatum evaluation

BACKGROUND

Pectus excavatum is a common chest wall anomaly in children. Pre-operative imaging for pectus excavatum is performed with CT, which is used to calculate the Haller index to determine the severity of pectus excavatum.

OBJECTIVE

To determine the correlation between Haller index values calculated with two-view chest radiographs and those calculated with CT and to determine, with CT as the reference standard, the diagnostic performance of radiographic Haller index for identifying cases that meet imaging criteria for surgical correction of pectus excavatum.

MATERIALS AND METHODS

For the period 2001-2009, our radiology information system was searched to identify all children who had undergone CT for Haller index calculation. Children who had also undergone two-view chest radiography (CXR) within 6 months of the CT were included in this retrospective study. Two radiologists independently calculated CT Haller index and radiographic Haller index. Data distributions were tested for normality with the Shapiro-Wilk W test. The associations between CT Haller index and radiographic Haller index were determined with the Spearman coefficient of rank correlation. Differences between CT Haller index and radiographic Haller index were tested with the Wilcoxon signed rank test. Haller index values were dichotomized into positive (>3.2) and negative (≤3.2) cases. Using CT as the reference standard, the sensitivity, specificity, and accuracy of radiographic Haller index in identifying children who meet imaging criteria for surgery were calculated.

RESULTS

CT and CXR for evaluation of pectus excavatum were available for 32 children (25 male; median age 14.5 years). With CT, the median Haller indices for observers 1 and 2 were 3.4 and 3.5 and with CXR 3.5 and 3.5. There were statistically significant correlations between the radiographic Haller index and CT Haller index estimated by the two observers [Spearman correlation coefficient (95% confidence interval) for observer 1 = 0.71 (0.48-0.85, P < 0.01) and for observer 2 = 0.77 (0.52-0.88, P < 0.01)]. A statistically significant correlation was found between the radiographic Haller index calculated by the two observers [Spearman correlation coefficient = 0.98 (0.95-0.99, P < 0.01)]. Using CT Haller index as the reference standard, radiographic Haller index had a sensitivity of 0.95 (0.75-0.99), specificity of 0.75 (0.43-0.94), and accuracy of 0.88 (0.72-0.95) for observer 1, and a sensitivity of 0.95 (0.75-0.99), specificity of 0.67 (0.35-0.90), and accuracy of 0.84 (0.68-0.93) for observer 2.

CONCLUSION

Radiographic Haller index correlates strongly with CT Haller index, has good interobserver correlation, and has a high diagnostic accuracy for pre-operative evaluation of pectus excavatum. We suggest that a CT of the chest is not required for pre-operative evaluation of pectus excavatum, and a two-view chest radiograph is sufficient for preoperative imaging of pectus excavatum.

Valuable lessons from two decades of pectus repair with the Willital–Hegemann procedure

OBJECTIVE

Pectus deformities are the most common congenital hereditary chest wall deformity. The aim of this study was to evaluate the efficacy of thoracic wall reconstruction using a uniform technique of internal stabilization with stainless-steel struts.

METHODS

Hospital charts of patients with chest wall deformities managed with the Willital-Hegemann procedure between January 1984 and January 2004 were reviewed.

RESULTS

Surgical corrections were performed in 1262 patients with pectus deformities (968 male and 294 female patients). The corrections were completed with successful repair in 1244 (98.6%) patients, along with a low complication rate of 5.7%. The median age of the patients was 14.9 years (range, 2-53 years). The follow-up period ranged from 2 to 12 years (mean, 5.4 years). Major recurrences were observed in 18 (1.4%) patients, and mild recurrences were observed in 46 (3.6%) patients. There was 1 death in this series. The struts were removed after a period of 24 to 36 months and were associated with a complication rate of 2.6% at the time of removal.

CONCLUSION

Custom-tailored molding of the chest wall can be achieved by using this method, which is not possible with minimal-access techniques. Open repair is effective for all variations of chest wall deformities and in patients of all ages, causes only mild pain, and produces good physiologic and cosmetic results. Improvement of subjective complaints, satisfactory long-term results, and improvement in psychological problems indicate the need to offer this procedure among other surgical correction options for low-risk children.

Anthropometric index for Pectus excavatum

BACKGROUND

Pectus excavatum (PEX) is a depression of the sternum in relation to the costal cartilages. Clinical and objective measures for classifying the defect are rare and difficult to apply. The present study aimed to create an anthropometric index (AI) for PEX as a method for diagnosis and for preoperative and postoperative assessment by comparing it to the Haller index (HI) and to the lower vertebral index (LVI).

METHODS

From December 2001 to February 2004, 2 groups of patients were studied at our institution: a) 30 patients with normal configuration of the thoracic cage, upon physical examination; b) 20 patients with PEX. The latter underwent surgery according to the Ravitch technique modified by Robicsek, and they were evaluated in the postoperative period. All patients were assessed by means of the AI (clinical), HI (tomographic), and LVI (radiographic) measures at the level of deepest deformity in the case of the PEX patients, and in the distal third of the sternum in the normal patients. The patients who had undergone surgery were once again measured between the 60th and the 80th postoperative days.

RESULTS

There was a high correlation between the AI and the HI (80% P < .001) and between the AI and the LVI (79% P < .001). The accuracy of the 3 indices was similar, in that the following cut points were established: AI = 0.12, HI = 3.10, and LVI = 0.25. Upon analyzing the preoperative results, we verified that for the 3 indices, over 75% of the patients with pectus excavatum were above the cut points and were confirmed as having the defect. In the postoperative results, the value of the indices found below the cut point was considered within the normal standard, and this occurred in 100% for the AI, in over 50% for the HI, and in 50% for the LVI.

CONCLUSIONS

The AI allowed adequate measurement of the defect, maintaining a) a high correlation with the HI and the LVI and a high accuracy, similar to the already acknowledged and published indices and b) an efficient comparison between the preoperative measurement and the postoperative results.

Lung function after the minimal invasive pectus excavatum repair (Nuss procedure)

Background

The Nuss procedure was introduced at our center in 1999. The operation was mainly performed for cosmesis. Little information is available regarding the influence of this operation on lung function.

Methods

The aim of this study, a prospective analysis, was to analyze the effect of the Nuss procedure on lung function variables. Between 1999 and 2007 a total of 203 patients with pectus excavatum were treated with the Nuss procedure, of whom 145 (104 male, 41 female) were located at Emma Children’s Hospital. In the latter subset of consecutive patients, static lung function variables [total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC)] and dynamic lung function variables [forced expired volume in 1 s (FEV₁), maximum expiratory flow (MEF₅₀)] were performed using spirometry and body box measurements at four time points: prior to operation (T0), 6 months after the Nuss procedure (T1, n = 111), prior to removal of the Nuss bar (T2, n = 74), and 6 months after removal (T3, n = 53). All values were expressed as a percent of normal values for sex, age, and height. Results were compared with a paired-samples t-test, with the level of significance at p = 0.05.

Results

At 6 months after bar insertion the TLC, FRC, VC, FEV₁, and MEF₅₀ showed a significant increase; and prior to bar removal the FRC and MEF₅₀ showed significantly increased values. At 6 months after Nuss bar removal, none of the lung function variables showed any significant change compared to the preoperative values.

Conclusion

After the Nuss procedure for pectus excavatum, there was no improvement of pulmonary function, but neither was the patient’s pulmonary function harmed by resolving a largely cosmetic problem.

Índice antropométrico para classificação quantitativa do pectus excavatum

INTRODUÇÃO: O pectus excavatum caracteriza-se por uma depressão do esterno e das cartilagens para-esternais inferiores. Medidas clínicas para classificar essas depressões são poucas e de difícil aplicação. OBJETIVO: Criar medidas clínicas para quantificar a deformidade e poder comparar os resultados entre os períodos pré e pós-operatório. MÉTODO: Dez pacientes portadores de pectus excavatum, foram operados utilizando-se a técnica de Robicsek modificada pelo grupo de Cirurgia Torácica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, sendo também medidos clínica e radiologicamente nos periodos pré e pós operatõrio. Dez pacientes controles que não apresentavam anormalidades torácicas clínicas e ou radiológicas foram medidos da mesma forma. O defeito foi avaliado no nível do manúbrio e da maior deformidade através do índice antropométrico e do índice de Haller. RESULTADOS: A análise multivariada para as médias do índice antropométrico mostrou diferenças significativas entre o pré operatório e o grupo controle e entre as médias do pré e do pós operatório, e diferença não significativa entre o pós operatório e o grupo controle. A mesma análise, aplicada às médias do índice de Haller, demonstrou os mesmos resultados. O estudo pareado entre as médias do pré e do pós operatório mostrou tratarem-se de grupos diferentes. A correlação canônica evidenciou que o índice antropométrico e o índice de Haller têm correlação de 86%. CONCLUSÃO: Pacientes portadores de pectus excavatum podem ter a deformidade quantificada através de medidas do índice antropométrico no pré e no pós operatório, as quais permitem uma avaliação objetiva e comparativa dos resultados, e são de fácil realização.

Acquired Thoracic Scoliosis following Minimally Invasive Repair of Pectus Excavatum

The minimally invasive pectus excavatum repair as described by Nuss et al. is rapidly gaining acceptance as an effective method of repair of severe pectus excavatum deformities in the pediatric population. It potentially offers several advantages over previous techniques. The incidence of major complications of the procedure has been reduced by recent modifications including utilization of video-assisted thoracoscopy during placement of the Lorenz pectus bar as well as utilizing the pectus bar stabilizer that provides more rigid fixation of the strut. We report two cases of acquired thoracic scoliosis following minimally invasive repair of severe pectus excavatum deformity. This particular complication has not been reported in previous literature and warrants concern. In both cases the thoracic scoliosis slowly improved with physical therapy and range-of-motion exercises.

Pulmonary function and exercise response in patients with pectus excavatum after Nuss repair

BACKGROUND/PURPOSE

The Ravitch repair of pectus excavatum removes segments of abnormal costal cartilages after which the sternum is elevated and stabilized. Some investigators have found a worsening in total lung capacity postoperatively. Recently, a technique has been used in which the costal cartilages are preserved, and the sternum is elevated with an internal steel bar (Nuss repair). The authors hypothesized that placement of a substernal bar in the first stage of the Nuss repair will not adversely affect pulmonary and exercise function.

METHODS

Patients who presented to the Children's Hospital of Buffalo for surgical repair of pectus excavatum from June 1997 through June 2000 underwent pulmonary function and exercise testing before and 6 to 12 months after the first stage of a Nuss repair.

RESULTS

Ten patients were studied (all boys; mean age at operative repair, 13.4 +/- 3 years). Mean baseline pulmonary function was normal, and no significant differences were seen before and after placement of the intrathoracic bar. Peak oxygen consumption was near normal, although work at VO2max was less than predicted (mean, 68.2% before v. 71.8% after surgery). V(E) was below normal and Vt/FVC was below the expected 50% to 60% level both before and after surgery (41.3% +/- 3 SE and 41.6% +/- 3 SE pre- and postoperatively, respectively).

CONCLUSIONS

Placement of a substernal steel bar in the first stage of the Nuss procedure for repair of pectus excavatum does not cause adverse effects on either static pulmonary function or on the ventilatory response to exercise.

Cardiopulmonary effects of closed repair of pectus excavatum

BACKGROUND/PURPOSE

Increasing numbers of patients with pectus excavatum defects are presenting for operative repair. Studies that follow-up with patients after open repair have found a decrease in pulmonary function with some improvement in cardiac output and exercise tolerance; however, these effects have not been examined systematically after closed or Nuss repair of pectus excavatum. This study examined the early postoperative effects of closed repair of pectus on pulmonary function, exercise tolerance, and cardiac function.

METHODS

Patients were followed up prospectively after initial evaluation for operation. All patients underwent preoperative computed tomography (CT) scan, and pre- and postoperative (3 months) pulmonary function studies, exercise tolerance, and echocardiographic evaluation of cardiac function.

RESULTS

Eleven patients underwent evaluation. Preoperative CT index was 4.1 +/- 0.9. Patients reported an improvement in subjective postoperative exercise tolerance (4.1 +/- 0.7; maximal, + 5). Pulmonary function studies (FVC and vital capacity) were significantly reduced at 3 months postsurgery: change in FVC, -0.67 +/- 0.92 L and VC, -0.5 +/- 0.72 L. Similarly, VO2 max was reduced: preoperative, 35.6 +/- 1.5 versus postoperative, 29.1 +/- 11.9 L/kg/min. Cardiac function was significantly improved postoperation (stroke volume preoperative, 61.6 +/- 25 versus 77.5 +/- 23 mL postoperative). All comparisons had a P value less than.05 by Student's paired t test.

CONCLUSIONS

These results show that closed repair of pectus excavatum is associated with a subjective improvement in exercise tolerance, which is paralleled by an increase in cardiac function and a decline in pulmonary function. These findings support the use of closed repair of pectus excavatum in patients who complain of subjective shortness of breath; further study is required to delineate the long-term cardiopulmonary implications after closed repair.

Treatment of pectus excavatum with bioabsorbable polylactide plates: Preliminary results

BACKGROUND/PURPOSE

Pectus excavatum usually is corrected by thoracoplasty using metal plates. Recently bioabsorbabe polylactide plates have been developed. The aim of this study was to compare outcome after use of metal and bioasorbable plates in thoracoplasty performed for correction of pectus excavatum.

METHODS

Eighty-three children (<16 years old) underwent thoracoplasty (Sulamaa's technique). In 75 patients, metallic plates, and in 8 patients, self-reinforced poly-L-lactide (SR-PLLA) plates, were used. Seven patients in the SR-PLLA group and 13 patients in the metal plate group were assessed 0.5 to 13 years postoperatively.

RESULTS

The mean operating time was 121 minutes in the metal plate group, and 87 minutes in the SR-PLLA plate group. In the metal plate group, complications were pain caused by instability of the metal plates (n = 17), wound infection (n = 3), recurrence of deformity (n = 3), postoperative pain (n = 3), pneumothorax (n = 1), and nonspecific postoperative fever (n = 1). Thirteen patients underwent reoperation to refix the position of the metallic plates. In the SR-PLLA group, one case of pneumothorax occurred, and plate fragment palpability caused local pain in one patient. Cosmetic results and lung function values were similar.

CONCLUSION

Our preliminary results show that bioabsorbable plates are a useful option in the treatment of pectus excavatum in children.

Why is exercise capacity reduced in subjects with pectus excavatum?

BACKGROUND

Exercise capacity is often limited in subjects with pectus excavatum (PE), but the mechanism is unknown.

OBJECTIVES

We attempted to quantify exercise capacity and to investigate whether limitation of venous return to the heart contributes to exercise intolerance in PE.

METHODS

A total of 13 patients with PE (mean age, 19 +/- 6 years) and 20 control subjects (mean age, 25 +/- 11 years) underwent sitting and supine incremental cycling and exercise Doppler stroke volume (SV) measurements.

RESULTS

Supine peak oxygen uptake (V'O(2)max) for the patients (1351 +/- 345 mL/min) and control subjects (1505 +/- 330 mL/min) was not different. In contrast, sitting V'O(2)max was lower in the patients than in the control subjects, 1480 +/- 462 and 1994 +/- 581 mL/min, respectively (P =.02). Supine exercise SV was not different between groups. Moreover, only in the patients with PE was supine exercise SV, 70 +/- 18 mL, higher than sitting exercise SV, 55 +/- 14 mL (P =.015). The corresponding values for the control subjects were 70 +/- 18 mL and 65 +/- 19 mL (P = NS).

CONCLUSIONS

Patients with PE exercising in the sitting position have reduced V'O(2)max and SV, whereas during supine exercise they approached the control values. The supine advantage in PE suggests that upright exercise capacity in this disease is affected by reduced filling of the heart in the non-supine position.

Cardiorespiratory function before and after corrective surgery in pectus excavatum

OBJECTIVE

To determine whether pectus excavatum (PE) results in cardiopulmonary abnormalities, and whether surgical repair results in improvement.

METHODS

We performed pulmonary function testing and incremental exercise testing in 36 adolescents with PE (aged 16 +/- 3 (SD) years) and 10 age-matched, healthy control subjects. Fifteen PE subjects were reexamined postoperatively, as were six control subjects.

RESULTS

Preoperatively, PE subjects had a significantly lower forced vital capacity than control subjects had (81% +/- 14% vs 98% +/- 9% of the predicted value; p < 0.001). Chest computed tomography ratios of internal transverse to antero-posterior diameters correlated inversely with total lung capacity (r = 0.56; p < 0.01). Fifty-eight percent of PE subjects had subjective complaints of exercise limitation. PE subjects exercised at a workload similar to that of control subjects. Maximal heart rate and O2 pulse did not differ between the two groups. Respiratory measurements during exercise were similar between the two groups. Respiratory measurements during exercise were similar between the two groups. Postoperatively there was no change in forced vital capacity (as a percentage of the predicted value). The PE subjects exercised for a slightly longer period and had a slightly higher O2 pulse, whereas control subjects showed no change.

CONCLUSION

Some subjects with PE have mild restrictive lung disease, which is not affected by surgical repair. Postoperatively they have a slight increase in exercise tolerance and O2 pulse, which suggests improved cardiac function during exercise. However, the clinical implications of this modest improvement are unclear.

Evaluation of pectus excavatum with repeated CT scans

The use of a single CT scan to evaluate the severity of pectus excavatum has been popular since its inception. However, there is no objective data to address the evolution of the deformity. Using repeated CT scans taken an average of 1 year and 3 months apart, eight children with pectus excavatum were prospectively followed. The initial pectus indices ranged from 3.6 to 6.8 (mean 5.4 +/- 1.3) and the follow-up indices, from 3.5 to 6.7 (mean 5.3 +/- 1.0). No progress of pectus excavatum was found during the study period. Our routine five axial chest CT sections also helped to specify a pectus index based on the central section taken through the deepest part of the deformity, and provided useful information for further conservative or surgical management.

Radiographic findings after pectus excavatum repair

Postoperative radiographic changes after pectus repair have not previously been described. We reviewed the chest radiographs of 65 children who underwent surgical repair of pectus excavatum between early 1985 and mid-1992. After operation, 64 children showed atelectasis, 38 had pleural effusions, 30 showed a congestion or edema pattern, 12 had pneumothorax, 21 showed fixation strut tilt or rotation, and 4 had pneumomediastinum. Despite the sometimes worrying radiographic appearance, these children uniformly did well clinically.

Pulmonary function before surgery for pectus excavatum and at long-term follow-up

Pulmonary function tests were performed before surgery on 152 patients who were operated on for pectus excavatum between 1970 and 1987 and at long-term follow-up to assess the degree of impairment and to investigate any changes caused by surgical correction. The mean age at surgery was 15.3 +/- 5.5 years. Pulmonary function was found to be restricted preoperatively. Multivariate analysis showed that preoperative pulmonary function was not related to age, the severity of the deformity at physical examination, or to pulmonary complaints. Only the patients with obstructive disease showed significantly more pulmonary complaints (p = 0.042). The total lung capacity (TLC) and inspiratory vital capacity (IVC) were significantly related to the age-corrected (delta) anteroposterior diameter of the chest (lower vertebral index [LVI]) (p = 0.0001). At follow-up (mean, 8.1 +/- 3.6 years), the restriction of pulmonary function was increased despite improvement in the symptoms of most patients and despite a significant increase in the anteroposterior diameter of the chest (p = 0.0001): the TLC was decreased from 83.7 percent predicted (pred) preoperatively to 73.8 percent pred (p = 0.0001) and the IVC from 78.3 percent pred to 70.7 percent pred (p = 0.0001). The surgical results were satisfactory in 83.6 percent. No relation was found between the changes in pulmonary function measured at follow-up and the surgical results. Only the age at surgery and the changes in the TLC and IVC at follow-up were significantly related (p = 0.0036, 0.0043, respectively), although the correlation coefficients were low (r = 27 percent and 28 percent, respectively). The reduction in lung function at follow-up was most pronounced in the patients who had the least functional impairment (TLC > 75 percent pred) preoperatively. No correlation was found between the changes in the pulmonary function test results at follow-up and follow-up interval, preoperative delta LVI, and the change in delta LVI at follow-up.