Life-threatening complications and mortality of minimally invasive pectus surgery

The prevalence and type of life-threatening complications related to the minimally invasive repair of pectus excavatum (MIRPE) and bar removal are unknown and underreported. The purpose of this communication is to make surgeons aware of the risk of these life threatening complications as well as the modifications which have been developed to prevent them.

METHODS

Data related to life-threatening complications of Pectus Excavatum (PE) patients was obtained from four sources: 1. A survey of Chest Wall International Group (CWIG) surgeons who specialize in repairing congenital chest wall malformations, 2. Papers and case reports presented at CWIG meetings, 3. Review of medico-legal cases from the USA and 4. A systematic review of the literature related to major complications post MIRPE.

RESULTS

From 1998 to 2016, we identified 27 published cases and 32 unreported life-threatening complications including: cardiac perforation, hemothorax, major vessel injury, lung injury, liver injury, gastrointestinal problems, and diaphragm injury. There were seven cases of major complications with bar removal (reported and non-reported) with two lethal outcomes. Mortality data with bar placement surgery: Four published death cases and seven unpublished death cases. The overall incidence of minor & major complications post MIRPE has been reported in the literature to be 2-20%. The true incidence of life-threatening complications and mortality is not known as we do not know the overall number of procedures performed worldwide. However, based on data extrapolated from survey information, the pectus bar manufacturer in the USA, literature reports, and data presented at CWIG meetings as to the number of cases performed we estimated that approximately fifty thousand cases have been performed and that the incidence of life-threatening complications is less than 0.1% with many occurring during the learning curve. Analysis of the cases identified in our survey revealed that previous chest surgery, pectus severity and inexperience were noted to be significant risk factors for mortality.

CONCLUSIONS

Published reports support the safety and efficacy of MIRPE; however major adverse outcomes are underreported. Although major complications with MIRPE and pectus bar removal surgery are very rare, awareness of the risk and mortality of life-threatening complications is essential to ensure optimal safety. Factors such as operative technique, patient age, pectus severity and asymmetry, previous chest surgery, and the surgeon's experience play a role in the overall incidence of such events. These preventable events can be avoided with proper training, mentoring, and the use of sternal elevation techniques.

TYPE OF STUDY

Treatment Study.

LEVEL OF EVIDENCE

Level IV.

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.

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.

Multicenter study of pectus excavatum, final report: complications, static/exercise pulmonary function, and anatomic outcomes

BACKGROUND

A multicenter study of pectus excavatum was described previously. This report presents our final results.

STUDY DESIGN

Patients treated surgically at 11 centers were followed prospectively. Each underwent a preoperative evaluation with CT scan, pulmonary function tests, and body image survey. Data were collected about associated conditions, complications, and perioperative pain. One year after treatment, patients underwent repeat chest CT scan, pulmonary function tests, and body image survey. A subset of 50 underwent exercise pulmonary function testing.

RESULTS

Of 327 patients, 284 underwent Nuss procedure and 43 underwent open procedure without mortality. Of 182 patients with complete follow-up (56%), 18% had late complications, similarly distributed, including substernal bar displacement in 7% and wound infection in 2%. Mean initial CT scan index of 4.4 improved to 3.0 post operation (severe >3.2, normal = 2.5). Computed tomography index improved at the deepest point (xiphoid) and also upper and middle sternum. Pulmonary function tests improved (forced vital capacity from 88% to 93%, forced expiratory volume in 1 second from 87% to 90%, and total lung capacity from 94% to 100% of predicted (p < 0.001 for each). VO2 max during peak exercise increased by 10.1% (p = 0.015) and O2 pulse by 19% (p = 0.007) in 20 subjects who completed both pre- and postoperative exercise tests.

CONCLUSIONS

There is significant improvement in lung function at rest and in VO2 max and O2 pulse after surgical correction of pectus excavatum, with CT index >3.2. Operative correction significantly reduces CT index and markedly improves the shape of the entire chest, and can be performed safely in a variety of centers.

Advancing our understanding of the inheritance and transmission of pectus excavatum

Pectus excavatum is the most common congenital chest wall abnormality expressed in children, yet its inheritance is poorly understood. Here we present the first comprehensive assessment of the inheritance of this disorder. After evaluating 48 pedigrees and 56 clinical traits of probands and family members, we find strong evidence of autosomal recessive, genetic control for this disorder. Additionally there is likely more than one pectus disease-associated allele, as well as a relatively large number of disease allele carriers in the human population. Some clinical traits appear important and may serve as reliable indicators for predicting the likelihood of pectus excavatum in children before severe symptoms present. Quantifying sex-ratio bias in probands demonstrates a highly significant male bias associated with pectus excavatum. When combined with pedigree data, sex-bias is indicative of sex-linked, sex-limited, and/or epigenetic control such as X-inactivation, reiterating a point made with pedigrees alone, which is that more than one mutation is likely responsible for this disorder.

Optoelectronic plethysmography demonstrates abrogation of regional chest wall motion dysfunction in patients with pectus excavatum after Nuss repair

PURPOSE

We previously demonstrated that patients with pectus excavatum (PE) have significantly decreased chest wall motion at the pectus defect compared with the rest of the chest vs unaffected individuals and use abdominal respiratory contributions to compensate for decreased upper chest wall motion. We hypothesize that PE repair will reverse chest wall motion dysfunction.

METHODS

A prospective, institutional review board-approved study compared patients with PE before and after Nuss repair. Informed consent was obtained before motion analysis. Sixty-four patients with uncorrected PE ages 10 to 21 years underwent optoelectronic plethysmography analysis. Repeat analysis was performed in 42 patients 6 months postoperative (PO).

RESULTS

Volume of the chest wall and its subdivisions were calculated. Total chest wall volume at rest was significantly increased after repair and in each thoracic compartment. PO patients developed increased midline marker excursion at the pectus defect and significantly decreased excursion at the level of the umbilicus.

CONCLUSIONS

Optoelectronic plethysmography kinematic analysis demonstrates that chest wall remodeling during Nuss repair results in increased thoracic volume. Chest wall motion dysfunction at the pectus defect is reversed after Nuss repair. Abdominal respiratory contributions are also markedly decreased. These findings may help to explain why patients with PE report an improvement in endurance after the Nuss procedure.

Regional chest wall motion dysfunction in patients with pectus excavatum demonstrated via optoelectronic plethysmography

BACKGROUND

Paradoxical chest wall motion is recognized clinically in pectus excavatum (PE). We report chest wall volume and motion differences between PE patients and unaffected individuals.

METHODS

A prospective, institutional review board-approved study compared nonoperated PE patients with normal controls (C). Subjects had deep breathing maneuvers captured by infrared cameras. Chest wall volume and excursion were calculated using optoelectronic plethysmography marker reconstruction combined with proprietary software (BTS Bioengineering, Milan, Italy).

RESULTS

One hundred nineteen patients underwent optoelectronic plethysmography analysis (PE: 64, C: 5). Total chest wall volume at rest was similar in both groups (PE: 13.6 L, C: 14.1 L, P = .55). During maximal inspiration, PE patients had a significant increase in the volume within the abdominal rib cage compartment (PE: 0.77 L, C: 0.6 L, P < .01). Patients with PE had 51% less midline marker excursion at the angle of Louis (P < .01), a 46% decrease at the level of the nipples (P < .01), and 28% less excursion at the xiphoid process (P = .02). At the level of the umbilicus, PE patients had 147% increase in midline marker excursion compared with controls (P < .01).

CONCLUSIONS

Optoelectronic plethysmography kinematic analysis allows for quantification of focal chest wall motion dysfunction. Patients with PE demonstrate significantly decreased chest wall motion at the area of the pectus defect and increased abdominal contributions to respiration compared with controls. This finding may help to explain exertional symptoms of easy fatigability or shortness of breath in PE.

One hundred patients with recurrent pectus excavatum repaired via the minimally invasive Nuss technique--effective in most regardless of initial operative approach

PURPOSE

Controversy exists as to the best operative approach to use in patients with failed pectus excavatum (PE) repair. We examined our institutional experience with redo minimally invasive PE repair along with the unique issues related to each technique.

METHODS

We conducted an institutional review board-approved review of a prospectively gathered database of all patients who underwent minimally invasive repair of PE.

RESULTS

From June 1987 to January 2010, 100 patients underwent minimally invasive repair for recurrent PE. Previous repairs included 42 Ravitch (RAV) procedures, 51 Nuss (NUS) procedures, 3 Leonard procedures, and 4 with previous NUS and RAV repairs. The median Haller index at reoperation was 4.99 (range, 2.4-20). Fifty-five percent of RAV patients and 25% of NUS patients required 2 or more bars (P = .01). Two RAV patients had intraoperative nonfatal cardiac arrest owing to thoracic chondrodystrophy--1 at insertion and 1 upon removal. Bar displacements occurred in 12% RAV and 7.8% NUS patients (P = .05). Overall reoperation for bar displacement is 9%.

CONCLUSIONS

The minimally invasive NUS technique is safe and effective for the correction of recurrent PE. Patients with prior NUS repair can have extensive pleural adhesions necessitating decortication during secondary repair. Patients with a previous RAV repair may have acquired thoracic chondrodystrophy that may require a greater number of pectus bars to be placed at secondary repair and greater risk for complications. We have a greater than 95% success rate regardless of initial repair technique.

A design for simulating and validating the nuss procedure for the minimally invasive correction of pectus excavatum

Surgical planners are used to achieve the optimal outcome for a surgery, especially in procedures where a positive aesthetic outcome is the primary goal, such as the Nuss procedure which is a minimally invasive surgery for correcting pectus excavatum (PE)--a congenital chest wall deformity. Although this procedure is routinely performed, the outcome depends mostly on the correct placement of the bar. It would be beneficial if a surgeon had a chance to practice and review possible strategies for placement of the corrective bar and the associated appearance of the chest. Therefore, we propose a strategy for the development and validation of a Nuss procedure surgical trainer and planner.

Minimally invasive repair of pectus excavatum in patients with Marfan syndrome and marfanoid features

PURPOSE

The presence of a pectus excavatum (PE) requiring surgical repair is a major skeletal feature of Marfan syndrome. Marfanoid patients have phenotypic findings but do not meet all diagnostic criteria. We sought to examine the clinical and management differences between Marfan syndrome patients and those who are marfanoid compared with all other patients undergoing minimally invasive PE repair.

METHODS

A retrospective institutional review board-approved review was conducted of a prospectively gathered database of all patients who underwent minimally invasive repair of PE. Patients were grouped according to diagnosis of Marfan syndrome (MAR), Marfanoid appearance (OID), and all others (ALL). Patient demographics, preoperative imaging and testing, operative strategy, complications, and postoperative surveys were evaluated. Fisher's Exact test and chi(2) were applied for statistical analysis.

RESULTS

From June 1987 to September 2008, 1192 patients underwent minimally invasive PE repair (MAR = 33, OID = 212, ALL = 947). There was a significantly higher proportion of females with either MAR or OID who underwent repair (21.5%vs 15.5%, P = .04). The MAR patients had significantly more severe PE determined by computed tomography index (MAR = 8.75, OID = 5.82, ALL = 4.94, P < .0001) and required multiple pectus bars (> or =2) to be placed during operation (MAR = 58%, OID = 36%, ALL = 29%, P = .001). There was a trend toward higher wound infection rates in MAR patients (MAR = 6%, OID = 1.4%, ALL = 1.3%, P = .07). The recurrence rate was similar among all groups (MAR = 0%, OID = 2%, ALL = 0.7%, P = .12). Successful outcome from surgeon perspective in either MAR or OID patients was similar to ALL (98%vs 98%, P = .88) and correlated well with patient satisfaction after repair (96%vs 95%, P = .43).

CONCLUSIONS

Minimally invasive PE repair is safe in patients with Marfan syndrome or marfanoid features with equally good results. Patients with Marfan syndrome have clinically more severe PE requiring multiple bars for chest repair and may have slightly higher wound infection rates. Patients are satisfied with minimally invasive repair despite a phenotypically more severe chest wall defect.

Surgical repair of pectus excavatum markedly improves body image and perceived ability for physical activity: multicenter study

OBJECTIVE

This study evaluated changes in both physical and psychosocial quality of life reported by the parent and child after surgical repair of pectus excavatum.

METHODS

As part of a multicenter study of pectus excavatum, a previously validated tool called the Pectus Excavatum Evaluation Questionnaire was administered by the research coordinator, via telephone, to parents and patients (8-21 years of age) before and 1 year after surgery. Eleven North American children's hospitals participated. From 2001 to 2006, 264 patients and 291 parents completed the initial questionnaire, and 247 patients and 274 parents completed the postoperative questionnaire. Responses used a Likert-type scale of 1 to 4, reflecting the extent or frequency of a particular experience, with higher values conveying less-desirable experience.

RESULTS

Preoperative psychosocial functioning was unrelated to objective pectus excavatum severity (computed tomographic index). Patients and their parents reported significant positive postoperative changes. Improvements occurred in both physical and psychosocial functioning, including less social self-consciousness and a more-favorable body image. For children, the body image component improved from 2.30+/-0.62 (mean+/-SD) to 1.40+/-0.42 after surgery and the physical difficulties component improved from 2.11+/-0.82 to 1.37+/-0.44. For the parent questionnaire, the child's emotional difficulties improved from 1.81+/-0.70 to 1.24+/-0.36, social self-consciousness improved from 2.86+/-1.03 to 1.33+/-0.68, and physical difficulties improved from 2.14+/-0.75 to 1.32+/-0.39. Ninety-seven percent of patients thought that surgery improved how their chest looked.

CONCLUSIONS

Surgical repair of pectus excavatum can significantly improve the body image difficulties and limitations on physical activity experienced by patients. These results should prompt physicians to consider the physiologic and psychological implications of pectus excavatum just as they would any other physical deformity known to have such consequences.

Minimally invasive surgical correction of chest wall deformities in children (Nuss procedure)

Pectus excavatum can be corrected with minimally invasive techniques that do not require costal cartilage resection or sternal osteotomy. At our institution, 947 patients have been safely and effectively managed with excellent long-term results and low morbidity.

Prospective Multicenter Study of Surgical Correction of Pectus Excavatum: Design, Perioperative Complications, Pain, and Baseline Pulmonary Function Facilitated by Internet-Based Data Collection

BACKGROUND

Given widespread adoption of the Nuss procedure, prospective multicenter study of management of pectus excavatum by both the open and Nuss procedures was thought desirable. Although surgical repair has been performed for more than 50 years, there are no prospective multicenter studies of its management.

STUDY DESIGN

This observational study followed pectus excavatum patients treated surgically at 11 centers in North America, according to the method of choice of the patient and surgeon. Before operation, all underwent evaluation with CT scan, pulmonary function tests, and body image survey. Data were collected about associated conditions, hospital complications, and perioperative pain. One year after completion of treatment, patients will repeat the preoperative evaluations. This article addresses early results only.

RESULTS

Of 416 patients screened, 327 were enrolled; 284 underwent the Nuss procedure and 43 had the open procedure. Median preoperative CT index was 4.4. Pulmonary function testing before operation showed mean forced vital capacity of 90% of predicted values; forced expiratory volume in 1 second (FEV(1)), 89% of predicted; and forced expiratory flow during the middle half of the forced vital capacity (FEF(25% to 75%)), 85% of predicted. Early postcorrection results showed that operations were performed without mortality and with minimal morbidity at 30 days postoperatively. Median hospital stay was 4 days. Postoperative pain was a median of 3 on a scale of 10 at time of discharge; the worst pain experienced was the same as was expected by the patients (median 8), and by 30 days after correction or operation, the median pain score was 1. Because of disproportionate enrollment and similar early complication rates, statistical comparison between operation types was limited.

CONCLUSIONS

Anatomically severe pectus excavatum is associated with abnormal pulmonary function. Initial operative correction performed at a variety of centers can be completed safely. Perioperative pain is successfully managed by current techniques.

Infectious complications after the Nuss repair in a series of 863 patients

PURPOSE

A nemesis of surgical implants is infection. We evaluated the various infectious complications after Nuss repair of pectus excavatum in 863 patients over 18 years.

METHODS

After institutional review board approval, a retrospective review of a prospectively gathered database of patients was performed who underwent minimally invasive repair of pectus excavatum and developed an infection. All patients received intravenous antibiotics before surgery continuing until discharge. Patients with a persistent fever after operation were discharged with oral antibiotics.

RESULTS

From January 1987 to September 2005, 863 patients underwent a minimally invasive pectus excavatum repair and 13 (1.5%) developed postoperative infections. These included 6 bar infections, 4 cases of cellulitis, and 3 stitch abscesses. Cellulitis was defined as erythema and warmth which responded to a single course of antibiotics. Bar infections were defined as an abscess in contact with the bar. Surgical drainage and long-term antibiotics resolved 3 of these abscesses, whereas 3 patients required early bar removal (1 after 3 months and 2 after 18 months). Cultures identified a single organism in each case and Staphylococcus aureus was the most common organism (83%) identified, and all being methicillin sensitive. All infections occurred on the side of the stabilizer if a stabilizer had been placed.

CONCLUSIONS

Infectious complications after Nuss repair are uncommon and occurred in 1.5% of our patients. Published rates of postoperative infection range from 1.0% to 6.8%. Superficial infections responded to antibiotics alone. Bar infection occurred in only 0.7% and required surgical drainage and long-term antibiotics. Only 3 of these (50% of bar infections and 0.34% overall) required early bar removal at 3 and 18 months because of recurring infections. Early bar removal should be a rare morbidity with the Nuss repair.

When it is not an infection: metal allergy after the Nuss procedure for repair of pectus excavatum

PURPOSE

Increasing use of implantable bars for minimally invasive pectus excavatum repair has introduced metal allergy (nickel and chromium) to pediatric surgeons. Metal allergy is a well-recognized entity in neurologic, orthopedic, and craniofacial surgery. This study was performed to evaluate metal allergy and its effects on treatment with the Nuss procedure in 862 patients.

METHODS

After institutional review board approval, we undertook a retrospective review of a prospectively gathered database of patients undergoing the Nuss procedure. Metal allergy was diagnosed either with the use of dermal patch or clinically, based on rash, fever, elevated erythrocyte sedimentation rate, cultures, and pathology specimens. Data collection included demographics, an allergy to jewelry, and history of atopy. Clinical outcomes including need for reoperation, removal of stainless steel bar, and replacement with titanium bar were evaluated.

RESULTS

Over an 18-year period (1987-2005), 862 patients underwent the Nuss procedure. Nineteen (2.2%) were diagnosed with metal allergy, with an average age of 14.7 years (9-23 years). Eighteen (95%) were males. A history of atopy was present in 9 (56%) patients. Ten (63%) patients presented with rash and erythema, 1 (6%) with granuloma, 5 (32%) with pleural effusion, and 3 (15%) were diagnosed on preoperative screening. Stainless steel bars were removed because of allergic skin breakdown in 3 patients, with 2 patients requiring replacement titanium bars. In all 3 of these patients, symptoms resolved after removal of stainless steel bars. Titanium bars were placed in the 3 patients who were diagnosed preoperatively with metal allergy, without event.

CONCLUSIONS

Allergy symptoms often are misdiagnosed as infection, but require different treatment. If a history of metal allergy or atopy is suggested preoperatively, the patient should be tested for metal allergy, and if positive, a titanium bar used. Because the consequences of metal allergy may include the need to replace the bar, pediatric surgeons should be aware of this occurrence.

Family study of the inheritance of pectus excavatum

BACKGROUND

The most common congenital deformity of the chest wall is pectus excavatum, a malformation that is present in between 1 in 400 and 1 in 1000 live births and causes the body of the sternum to be displaced, producing a depression. There are many different shapes of the pectus, and multiple factors probably contribute to the final form. The etiology of pectus excavatum is uncertain, but a familial tendency has been found in clinical experience, where it may be seen in more than one sibling. Pectus excavatum is commonly associated with connective tissue disorders such as Marfan and Ehlers Danlos syndromes. Extensive literature review failed to identify articles documenting families with multiple affected members.

PURPOSE

The purpose of this study was to collect evidence that pectus excavatum is familial and may be an inherited disorder.

METHODS

Using the Children's Surgical Specialty Group database at Children's Hospital of The King's Daughters, families with more than one affected individual were selected. With Institutional Review Board-approved informed consent, 34 families agreed to participate. Family histories were obtained, and a 4-generation pedigree was constructed for each family. Forty questions were asked about each individual's medical history, and comprehensive systems review included features of connective tissue-related problems. Inheritance patterns for each family were determined by pedigree analysis.

RESULTS

A total of 14 families suggested autosomal dominant inheritance, 4 families suggested autosomal recessive inheritance, and 6 families suggested X-linked recessive inheritance. Ten families had complex inheritance patterns. Pectus excavatum occurred more frequently in males than in females (1.8:1). Long arms, legs, and fingers; high-arched palate; mitral valve prolapse; heart arrhythmia; scoliosis; double jointedness; flexibility; flat feet; childhood myopia; poor healing; and easy bruising were commonly associated with pectus excavatum.

CONCLUSIONS

Pedigree analysis of 34 families provides evidence that pectus excavatum is an inherited disorder, possibly of connective tissue. Although some families demonstrate apparent Mendelian inheritance, most appear to be multifactorial.

Classification of the dysmorphology of pectus excavatum

BACKGROUND/PURPOSE

To describe the dysmorphology of pectus excavatum, the most common congenital chest wall anomaly.

METHODS

A stratified sample of 64 patients, representative of a patient population with pectus excavatum of the Children's Hospital of King's Daughters in Norfolk, VA, was described and classified. The sample was stratified by sex to represent a 4:1 male-to-female ratio. The sample was further stratified to represent categories of age (3-10, 11-16, and 17 years and older). Preoperative photos and baseline chest computed tomography scans were examined and categorized according to the chief criteria, including asymmetry/symmetry of the depression, localized vs diffuse morphology, sternal torsion, cause of asymmetric appearance, and the length of the depression.

RESULTS

Useful morphologic distinctions in pectus excavatum are localized depressions vs diffuse depressions, short and long length, symmetry, sternal torsion, slope/position of absolute depth, and unique patterns such as the horns of steer depression.

CONCLUSIONS

These classifications simplify the diagnosis of pectus excavatum, aid in corrective surgery, and should improve correlation of phenotype and genotype in future genetic analysis.

Reliability of a standardized protocol to calculate cross-sectional chest area and severity indices to evaluate pectus excavatum

PURPOSE

In evaluating the impact of surgical repair of pectus excavatum, the Haller index developed for preoperative decision-making purposes may be inadequate to quantify postoperative changes in shape of the chest. Individual patients may also have chest characteristics that impact the success of repair, many of which would be unlikely to be measured by the Haller index alone. We have developed a protocol that measures the cross-sectional chest area and the asymmetry index along with the Haller index to more completely quantify the nature of the deformity. The purpose of this study was to determine the reliability of this protocol in the interpretation of chest computed tomography images from multiple sites. The protocol was developed as part of a multicenter study of clinical outcomes after surgical repair of pectus excavatum.

METHODS

Two radiologists independently selected 5 images from each of 32 computed tomography scans from multicenter study participants according to the protocol. A digitizer was used to measure the diameters and cross-sectional areas of the images selected; these results were used to calculate the Haller and asymmetry indices. The protocol was tested for intradigitizer and interradiologist reliability. Using the Haller and asymmetry indices, we also assessed agreement between radiologists classifying patients as abnormal.

RESULTS

Agreement was uniformly high for all comparisons (all Lin's concordance coefficients >0.99 and all Cohen's kappa's >0.85, all agreement on classification of patients >95%) indicating almost perfect agreement. Disagreement on classification of patients using the Haller and asymmetry index was at the cut points for abnormality.

CONCLUSION

The protocol was found to be a highly reliable method for deriving the cross-sectional area of the chest and the Haller and asymmetry indices and for classifying patients for surgical eligibility. Borderline cases should be examined carefully to determine the appropriateness of surgical intervention. Cross-sectional area can be measured reliably using this protocol and thus may be useful in quantifying the success of surgical intervention.

Recent experiences with minimally invasive pectus excavatum repair "Nuss procedure"

OBJECTIVE

To review the new technical modifications and results of 668 patients who have had pectus excavatum repair utilizing the minimally invasive technique.

METHODS

A retrospective chart review was conducted of 668 patients undergoing minimally invasive pectus repair from 1987 through July 2004. Since 1997, a standardized treatment pathway was implemented. Preoperative evaluation included computed tomography (CT) scan, pulmonary function tests, and cardiac evaluations with electrocardiogram and echocardiogram. Indications for operation included at least 2 of the following: progression of the deformity, Haller CT index greater than 3.25, mitral valve prolapse, cardiac compression or displacement, pulmonary function studies that indicate restrictive or obstructive airway disease, previous failed open or minimally invasive pectus repair. Technical and design modifications since 1998 have included routine thoracoscopy, the use of an introducer/dissector for creating the substernal tunnel, elevating the sternum, and routine use of a wired lateral stabilizer and polydioxanone suture (PDS) sutures around the bar and underlying rib to prevent bar displacement. The bar is removed as an outpatient procedure in 2 to 4 years.

RESULTS

In 668 patients undergoing minimally invasive pectus repairs, single bars were used in 78.1% and double in 21.7%. Lateral stabilizers were applied in 99.8% and were wired for further stability in 71%. Bar shifts before the use of stabilizers were 14.3%, which decreased to 4.6% after stabilizers were placed and 0.8% with a wired stabilizer and PDS sutures. Results were excellent in 78.5%, good in 13.1%, fair in 4.7% and failed in 3.7% after more than 1 year post bar removal.

CONCLUSION

The minimally invasive technique has evolved into an effective method of pectus excavatum repair. Modifications of the technique have reduced complications. Long-term results continue to be excellent.

Impact of pectus excavatum on pulmonary function before and after repair with the Nuss procedure

BACKGROUND/PURPOSE

Patient reports of preoperative exercise intolerance and improvement after surgical repair of pectus excavatum (Pex) have been documented but not substantiated in laboratory studies. This may be because no study has been large enough to determine if pulmonary function tests (PFTs) in the Pex population are significantly different from the normal population, and none has assessed improvement in pulmonary function after Nuss bar removal.

METHODS

The authors studied PFT results in 408 Pex patients before repair and in a subset of 45 patients after Nuss procedure and bar removal. Significance of differences in percent predicted (using Knudson's equations) was tested using t tests (parametric) or sign tests (nonparametric). Normal was defined as 100% of predicted for forced vital capacity (FVC), forced expired volume in 1 second (FEV1), and forced expiratory flow (FEF25%-75%).

RESULTS

Preoperatively, FVC and FEV1 medians were lower than the normal by 13%, whereas the FEF 25-75 median was lower than normal by 20% (all P < .01). The postoperative group had statistically significant improvement after surgery for all parameters. Patients older than 11 years at the time of surgery had lower preoperative values and larger mean post-bar removal improvement than the younger patients. An older patient with a preoperative FEF25-75 score of 80% of normal would be predicted by these data to have a postoperative FEF25-75 of 97%, indicating almost complete normalization for this function.

CONCLUSIONS

These results demonstrate that preoperatively Pex patients as a group have decreased lung function relative to normal patients. After Nuss procedure and bar removal, we show a small but significant improvement in pulmonary function. These results are consistent with patient reports of clinical improvement and indicate the need for more in-depth tests of cardiopulmonary function under exercise conditions to elucidate the mechanism.

The minimally invasive Nuss technique for recurrent or failed pectus excavatum repair in 50 patients

PURPOSE

The aim of this study was to demonstrate the efficacy of the minimally invasive technique for recurrent pectus excavatum.

METHODS

Fifty patients with recurrent pectus excavatum underwent a secondary repair using the minimally invasive technique. Data were reviewed for preoperative symptomatology, surgical data, and postoperative results.

RESULTS

Prior repairs included 27 open Ravitch procedures, 23 minimally invasive (Nuss) procedures, and 2 Leonard procedures. The prior Leonard patients were also prior Ravitches and are therefore counted only once in the analyses. The median age was 16.0 years (range, 3-25 years). The median computed tomography index was 5.3 (range, 2.9-20). Presenting symptoms included shortness of breath (80%), chest pain (70%), asthma or asthma symptoms (26%), and frequent upper respiratory tract infections (14%). Both computed tomography scan and physical exam confirmed cardiac compression and cardiac displacement. Cardiology evaluations confirmed cardiac compression (62%), cardiac displacement (72%), mitral valve prolapse (22%), murmurs (24%), and other cardiac abnormalities (30%). Preoperative pulmonary function tests demonstrated values below 80% normal in more than 50% of patients. Pectus repair was done using a single pectus bar (66%), 2 bars (32%), or 3 bars (2%). Stabilizers were used in 88% of the patients. Median length of surgical time did not significantly differ from that of primary surgeries. Complications were slightly higher than those in primary repairs and included pneumothorax requiring chest tube (14%), hemothorax (8%), pleural effusion requiring drainage (8%), pericarditis (4%), pneumonia (4%), and wound infection (2%). There were no deaths or cardiac perforations. Initial postoperative results were excellent in 70%, good in 28%, and fair in 2%. Late complications of bar shift requiring revision occurred in 8%. Seventeen patients have had bar removals with 9 patients being more than 1 year postremoval. For the 17 patients who are postremoval, excellent results have been maintained in 8 (47%), good in 7 (41%), fair in 1 (6%), and failed in 1 (6%). There have been no recurrences postremoval.

CONCLUSIONS

Although failed or recurrent pectus excavatum repairs are technically more challenging, reoperative correction by the Nuss procedure has met with excellent success.

Chest wall anomalies: pectus excavatum and pectus carinatum

Pectus excavatum, the concave depression of the breast bone, comprises most chest wall anomalies. The Nuss procedure, a minimally invasive procedure to correct pectus excavatum, has revolutionized the management of this disease over the past decade. The results and complications of this procedure are discussed. The surgical management of the less common pectus carinatum or "pigeon breast" also is reviewed.

A pilot study of the impact of surgical repair on disease-specific quality of life among patients with pectus excavatum

BACKGROUND

This study was conducted to determine the ability of 2 questionnaires (ie, child and parent versions) to measure physical and psychosocial quality-of-life changes after surgical repair of pectus excavatum.

METHODS

The authors administered these questionnaires by telephone interviews with 22 parents and 19 children (ages 8 to 18) before surgery and 6 to 12 months after repair by the Nuss procedure.

RESULTS

The instruments had high test-retest reliability (Rho > 0.6 for all retained questions). Children reported significant improvements in exercise intolerance, shortness of breath, and tiredness. Of 9 questions asking the children how they feel or act about their bodies, all but one question showed significant improvement after surgery. Parents also reported significant improvements in their child's exercise tolerance, chest pain, shortness of breath, and tiredness and decreases in the frequency of the child being frustrated, sad, self-conscious, and isolated.

CONCLUSIONS

These questionnaires appear to be more than adequate to measure disease-specific quality-of-life changes after surgery. These data confirm for the first time that surgical repair of pectus excavatum has a positive impact on both the physical and psychosocial well-being of the child.

Review and discussion of the complications of minimally invasive pectus excavatum repair

PURPOSE

To review and discuss the complications of minimally invasive pectus excavatum repair.

METHODS

329 patients underwent minimally invasive pectus repair between January 1987 and August 2000, including 14 patients who recurred after previous Ravitch repairs, 10 failed Nuss repairs (eight done elsewhere) and two failed Leonard repairs. All patients received antibiotics and vigorous incentive spirometry to prevent atelectasis, pneumonia and bar infection. Epidural anesthesia was used for postoperative analgesia to keep patients comfortable and stable postoperatively and to prevent bar displacement. Thoracoscopy was used during bar insertion to minimize the risk of mediastinal injury and to select the best position for the bar. A new introducer was developed to elevate the sternum before bar insertion. A stabilizing bar was created to minimize bar displacement. The duration of sternal bracing has been increased from two years to three or four years in selected patients.

COMPLICATIONS

There were no deaths, no cardiac perforations and no cases of thoracic chondrodystrophy. Pneumothorax with spontaneous resolution occurred in 52 % of the patients, with 1.2 % requiring simple aspiration and 1.5 % requiring chest tube drainage. This complication has essentially been eliminated by using a "water seal system". Pericarditis occurred in 2.4 % with good response to Indomethacin in six out of eight patients and two patients also required pericardial fluid aspiration. Pneumonia occurred in 0.9 %. Wound infection occurred in 2.6 % resulting in bar infection in three out of the seven patients. Long-term antibiotics were successful in curing the infection in one patient, whereas the other two required bar removal at 12 and 18 months, respectively. Bar displacement occurred in 8.8 % of patients. However, the introduction of stabilizers decreased the incidence from 15.7 % before the use of stabilizers to 5.4 % with stabilizers. Wiring the bar and stabilizer together has decreased the incidence even further.

RESULTS

Long-term outcome after bar removal showed an excellent result in 71 %, good result in 21 % and recurrence in 7.8 %.

CONCLUSION

The minimally invasive technique has a low complication rate with excellent long-term results.

Experience and modification update for the minimally invasive Nuss technique for pectus excavatum repair in 303 patients

PURPOSE

The aim of this study is to review the new technical modifications and results of 303 patients who have had pectus excavatum repair utilizing the minimally invasive technique.

METHODS

A retrospective chart review was conducted of 303 patients undergoing minimally invasive pectus repair from 1987 through August 2000. Since 1997, a standardized treatment pathway was implemented, and 261 of the 303 patients have been treated on this pathway. Preoperative evaluation included computed tomography (CT) scan, pulmonary function tests (PFT), and cardiac evaluations with electrocardiogram (EKG) and echocardiogram. Indications for operation included at least 2 of the following: progression of the deformity, exercise intolerance or restrictive disease on PFT, Haller CT index greater than 3.2, mitral valve prolapse (MVP), or cardiac compression. Technical and design modifications since 1998 have included routine thoracoscopy, the use of an introducer/dissector for creating the substernal tunnel and elevating the sternum, and routine use of a wired lateral stabilizer to prevent bar displacement. The bar is removed as an outpatient procedure in 2 to 4 years.

RESULTS

In 303 patients undergoing minimally invasive pectus repairs, single bars were used in 87% and double in 13%. Lateral stabilizers were applied in 70% of patients and were wired for further stability in 65%. Bar shifts before the use of stabilizers were 15%, which decreased to 6% after stabilizers were placed and 5% with a wired stabilizer. Excellent results were noted in 85% with failure in only 1 patient. Complications included pneumothorax with spontaneous resolution in half of the patients and pericarditis in 7.

CONCLUSIONS

The minimally invasive technique has evolved into an effective method of pectus excavatum repair. Modifications of the technique have reduced complications. Long-term results continue to be excellent.

The Nuss procedure for pectus excavatum correction

Pectus excavatum is an anterior chest wall deformity that now can be corrected with a minimally invasive technique known as the Nuss procedure. Patient criteria and assessment for this new surgical procedure are defined clearly in advance to ensure the need for surgical intervention. A multidisciplinary team approach has been established at Children's Hospital of The King's Daughters, Norfolk, Va. Team members work cooperatively throughout the perioperative cycle, addressing not only the surgical procedure but also pain management and postoperative recovery. This dedicated team approach helps ensure a successful outcome for the patient.

Radiologic considerations in patients undergoing the Nuss procedure for correction of pectus excavatum

The Nuss procedure has succeeded in minimizing incisions, blood loss, sternal fracturing, operating room time, recovery time, and length of hospital stay. Knowledge of the pre- and postoperative radiologic considerations is essential in providing appropriate imaging support to the surgeons performing this innovative, minimally invasive procedure.

The effects of a pediatric unilateral inguinal hernia clinical pathway on quality and cost

BACKGROUND/PURPOSE

The purpose of this study is to discover whether a pediatric inguinal hernia surgical clinical pathway (CP) reduces the frequency of wound infections, return visits, times associated with surgical repair, or costs.

METHODS

A multidisciplinary team developed the inguinal hernia surgical clinical pathway. Healthy children greater than 50 weeks gestational age who required unilateral hernia repair were considered for the study. Two groups were formed: (1) an intervention group selected randomly (n = 46, CI = 95%, power = .80) from patients enrolled from November 1996 through April 1997, and (2) a retrospective cohort control group (n = 46) matched to each intervention patient by age, gender, and medical history. Analysis of variance and chi2 testing were used to test for significant differences between the 2 groups in postoperative wound infections, readmission and emergency department return visits within 72 hours, times associated with surgical repair, and costs.

RESULTS

There were no significant differences in postoperative wound infections, times associated with surgical repair, or readmission rates within 72 hours. Total cost significantly decreased, by 10% (P< or = .05), for pathway patients ($982 v $880).

CONCLUSION

These results show that the use of a pediatric inguinal hernia surgical clinical pathway is associated with reduced cost while maintaining quality of care.

Outcome analysis of minimally invasive repair of pectus excavatum: review of 251 cases

BACKGROUND/PURPOSE

Since the first report in 1997 by Dr Nuss of the technique for minimally invasive repair of pectus excavatum (MIRPE), the popularity and demand for this operation has increased dramatically. Many pediatric surgeons became familiarized with MIRPE and have applied it to a large number of patients. Outcomes and complications have not yet been defined.

METHODS

A comprehensive survey of APSA members was conducted to review technical problems, complications, and outcomes of this new technique.

RESULTS

Of the 74 survey responders, 31 (42%) currently use the MIRPE as their procedure of choice, and 251 cases were reviewed. A total of 74.2% of surgeons relied on direct observation and written documentation to obtain training in MIRPE. Less than 60% used the chest index in the preoperative assessment. A total of 98% used the Walter Lorenz bar for the MIRPE. The most common complication was bar displacement or rotation requiring reoperation (9.2%). Pneumothorax requiring tube thoracostomy was reported in 4.8%. Less common problems included infectious complications (2%), pleural effusion (2%), thoracic outlet obstruction (0.8%), cardiac injury (0.4%), sternal erosion (0.4%), pericarditis (0.4%), and anterior thoracic artery pseudoaneurysm (0.4%). Three patients (1.2%) required early strut removal. Reoperation using the open modified Ravitch approach was performed in 2 patients (0.8%). Most surgeons indicated that teenaged patients (>15 years old) were at higher risk for complications. Thoracoscopy in combination with MIRPE was used by 61% of the surgeons. Overall patient satisfaction was rated as excellent or good (96.5%).

CONCLUSIONS

The relatively high incidence of problems with MIRPE is probably related to the learning curve associated with the introduction of this new technique. Awareness of technical details, careful patient selection, use of a stabilizing bar, and thoracoscopy likely will result in decreased complications. Long-term results are yet to be determined. The development of a national registry is of great importance for further outcome analysis of MIRPE.

Initial assessment of gene diversity for the oomycete pathogen Phytophthora infestans based on expressed sequences

A total of 1000 expressed sequence tags (ESTs) corresponding to 760 unique sequence sets were identified using random sequencing of clones from a cDNA library constructed from mycelial RNA of Phytophthora infestans. A number of software programs, represented by a relational database and an analysis pipeline, were developed for the automated analysis and storage of the EST sequence data. A set of 419 nonredundant sequences, which correspond to a total of 632 ESTs (63.2%), were identified as showing significant matches to sequences deposited in public databases. A putative cellular identity and role was assigned to all 419 sequences. All major functional categories were represented by at least several ESTs. Four novel cDNAs containing sequences related to elicitins, a family of structurally related proteins that induce the hypersensitive response and condition avirulence of P. infestans on Nicotiana plants, were among the most notable genes identified. Two of these elicitin-like cDNAs were among the most abundant cDNAs examined. The set also contained several ESTs with high sequence similarity to unique plant genes.

A 10-year review of a minimally invasive technique for the correction of pectus excavatum

PURPOSE

The aim of this study was to assess the results of a 10-year experience with a minimally invasive operation that requires neither cartilage incision nor resection for correction of pectus excavatum.

METHODS

From 1987 to 1996, 148 patients were evaluated for chest wall deformity. Fifty of 127 patients suffering from pectus excavatum were selected for surgical correction. Eight older patients underwent the Ravitch procedure, and 42 patients under age 15 were treated by the minimally invasive technique. A convex steel bar is inserted under the sternum through small bilateral thoracic incisions. The steel bar is inserted with the convexity facing posteriorly, and when it is in position, the bar is turned over, thereby correcting the deformity. After 2 years, when permanent remolding has occurred, the bar is removed in an outpatient procedure.

RESULTS

Of 42 patients who had the minimally invasive procedure, 30 have undergone bar removal. Initial excellent results were maintained in 22, good results in four, fair in two, and poor in two, with mean follow-up since surgery of 4.6 years (range, 1 to 9.2 years). Mean follow-up since bar removal is 2.8 years (range, 6 months to 7 years). Average blood loss was 15 mL. Average length of hospital stay was 4.3 days. Patients returned to full activity after 1 month. Complications were pneumothorax in four patients, requiring thoracostomy in one patient; superficial wound infection in one patient; and displacement of the steel bar requiring revision in two patients. The fair and poor results occurred early in the series because (1) the bar was too soft (three patients), (2) the sternum was too soft in one of the patients with Marfan's syndrome, and (3) in one patient with complex thoracic anomalies, the bar was removed too soon.

CONCLUSIONS

This minimally invasive technique, which requires neither cartilage incision nor resection, is effective. Since increasing the strength of the steel bar and inserting two bars where necessary, we have had excellent long-term results. The upper limits of age for this procedure require further evaluation.

Growth patterns, ultrastructure, and chromosomal constitution of normal kidney and nephroblastoma cells in short-term culture

Nephrectomies were performed on four children with nephroblastomas (Wilms' tumor). Tumor tissue and normal kidney tissue were taken from each patient and were cultured. The in vitro characteristics of the cultured cells were then compared with their known in vivo characteristics. The normal kidney cells showed uniform cell morphology, had a relatively slow and orderly growth pattern and had the usual diploid chromosomal constitution. The tumor cells on the other hand were irregular in morphology and had a rapid and disorderly growth pattern. Electron microscopic examination confirmed the variation in the tumor cell morphology. In addition, microfilaments were seen to be abnormally abundant in many of the cells and some cells contained membrane-bound granules. Desmosomes were absent. Chromosome analyses showed cells from three of the nephroblastoma samples to maintain a constant hyperdiploid karyotype during the first few passages in vitro, whereas the normal kidney cells continued to have the normal diploid karyotype. Our study suggests that nephroblastoma and normal kidney cells are stable in culture, that is they retain most of their cellular characteristics in vitro and do not undergo rapid dedifferentitation in short-term culture.

Successful management of oesophageal atresia type IIIa by oesophageal stretching: a case report

A case of oesophageal atresia type IIIa and anorectal agenesis is presented, in which stretching of the oesophagus resulted in successful delayed oesophageal anastomosis, thereby avoiding the need for colonic oesophageal replacement and thus greatly facilitating the repair of the anorectal agenesis. The literature is reviewed and it is concluded that every attempt should be made to effect oesophageal anastomosis, because the colon interposition procedure carries not only a high early mortality but also a high late complication rate.

Late-onset intestinal obstruction in cystic fibrosis--meconium ileus equivalent

Four patients who suffered from cystic fibrosis and late-onset bowel obstruction (meconium ileus equivalent), and who were treated by surgery, are discussed. The importance of early correct diagnosis is stressed, since surgery may be prevented if bowel washouts and oral medications are given before the condition becomes complicated.