Michael E. Dunham

Pulmonary artery sling: results with median sternotomy, cardiopulmonary bypass, and reimplantation

BACKGROUND The classic surgical approach to pulmonary artery (PA) sling has been through a left thoracotomy with division of the left PA and reimplantation into the main PA anterior to the trachea. Another approach is anterior left PA translocation with distal tracheal resection. Since 1985, we have repaired PA sling with a median sternotomy approach, cardiopulmonary bypass, and division and reimplantation of the left PA into the main PA with simultaneous repair of associated tracheal stenosis. The purpose of this review is to determine the outcome of that strategy. METHODS From 1985 to 1998, 16 infants had surgical treatment of PA sling, 14 had left PA division and reimplantation into the MPA, 2 patients had repair using the translocation technique. Mean age at repair was 6.9 months, median age was 4 months. All infants, except 1 with an absent right lung, were operated on at the time of diagnosis. All had rigid bronchoscopy, which revealed associated complete tracheal rings in 12 patients. Seven patients had tracheal repair with pericardial tracheoplasty, 4 had repair using a tracheal autograft technique, and 2 had a distal tracheal resection (one for tracheomalacia). Of the 2 patients having the translocation technique, 1 had a severely hypoplastic right lung and the other had complete absence of the right lung. RESULTS There has been no operative mortality. Hospital stay ranged from 5 to 188 days (mean 36 +/- 42 days). There was 1 late death 7 months postoperatively from respiratory complications of pericardial tracheoplasty. All left pulmonary arteries are patent and blood flow to the left lung by nuclear scan (n = 10) ranges from 24% to 46% (mean 35% +/- 9%). CONCLUSION The strategy of median sternotomy, cardiopulmonary bypass, and left PA division and reimplantation into the main PA with simultaneous tracheal repair has resulted in a low operative mortality and excellent patency of the left pulmonary artery. Results with repair of the commonly associated complete tracheal rings has recently improved with the use of the free tracheal autograft technique.

Repair of congenital tracheal stenosis with a free tracheal autograft.

OBJECTIVES Evaluate the results of a technique for repair of congenital tracheal stenosis by use of a free tracheal autograft. METHODS Between January 1996 and July 1997, six infants with congenital tracheal stenosis resulting from complete tracheal rings underwent repair with a free tracheal autograft. Mean age at the time of repair was 4.9 months; mean weight was 5.4 kg. The approach was through a median sternotomy with cardiopulmonary bypass for respiratory support. The trachea was incised anteriorly through the area of stenosis, the midportion of the stenotic trachea was excised, and an end-to-end anastomosis was carried out posteriorly. The excised tracheal segment (1.3 to 2.2 cm long) was used as a free autograft to patch the lower trachea anteriorly. In four infants the autograft was augmented in the upper trachea with pericardium; in two patients with a shorter length of stenosis, the autograft completed the repair. Simultaneous pulmonary artery sling repair (4), ligation and division of patent ductus arteriosus (3), cricoid split (2), atrial and ventricular septal defect repair (1), and complete atrioventricular canal repair (1) were performed at the time of tracheal repair. RESULTS The infants were extubated and discharged at a mean of 13 and 23 days postoperatively, respectively. One infant had recurrent tracheal stenosis related to the pericardial patch and required a tracheal stent and tracheostomy 4 months postoperatively. Our mean follow-up is 11 months. Bronchoscopic findings currently show widely patent tracheal lumina in all infants. CONCLUSIONS The technique of free tracheal autograft with and without pericardial augmentation was successful in opening the airway of six infants with congenital tracheal stenosis and is currently our procedure of choice for children with this diagnosis.

Reoperation after pericardial patch tracheoplasty

Between 1982 and 1995, 28 infants underwent pericardial tracheoplasty for long-segment tracheal stenosis. Seven of these infants required reoperation or stenting for residual or recurrent tracheal or bronchial stenosis. Revisions were performed 2 to 6 months after the original procedure with cardiopulmonary bypass and bronchoscopic guidance. Two patients underwent repeat pericardial patch tracheoplasty, and four patients underwent insertion of a rib cartilage graft. Two of these patients required Palmaz wire expandable stents and one other patient also underwent stent placement. There was one late death 1 year after cartilage graft insertion. The authors identified three risk factors for reoperation after tracheoplasty; younger age at initial surgery and associated pulmonary artery sling or tracheal right upper lobe bronchus. Good intermediate results are possible in this difficult group of children using a selective and inclusive strategy for tracheal enlargement that includes repeat pericardial tracheoplasty, autologous cartilage grafts, and expandable wire stents.

Slide Tracheoplasty in the Management of Congenital Tracheal Stenosis

Long-segment congenital tracheal stenosis (LSCTS) is a rare condition. Originally, it was felt to be uniformly fatal; however, advances in technique have made surgical repair and survival possible. Our objective is to report results and technique of slide tracheoplasty for the treatment of LSCTS in the context of the overall experience at the Childrens Memorial Hospital in Chicago. We reviewed 37 cases of infants and children with LSCTS. Thirty of the 37 infants underwent surgical intervention. Slide tracheoplasty resulted in survival in 1 of 2 infants, and pericardial patch tracheoplasty resulted in survival in 21 of 28 (75%). Of the 30 patients who had surgical repair, 7 (23%) have died, and 1 has been lost to follow-up (3%). Follow-up has ranged from 6 months to 13 years. Slide tracheoplasty is a satisfactory adjunct to existing techniques. With early diagnosis and appropriate management of LSCTS, survival is possible in a majority of patients.

Bilateral Choanal Atresia Associated with Malformation of the Anterior Skull Base: Embryogenesis and Clinical Implications

A number of craniofacial and systemic malformations have been described in association with choanal atresia. We report a case of bilateral choanal atresia associated with congenital absence of the cribriform plate, crista galli, and perpendicular plate of the ethmoid bone. The anterior skull base defect was detected by using high-resolution computed tomography with three-dimensional reconstructions. The findings support the mesodermal flow theory of choanal atresia, in which there is excess migration of neural crest cells into the developing nasal septum and posterior choanae. This occurs at the expense of cells that would otherwise form the rest of the ethmoid complex. Clinical implications include the need for adequate preoperative imaging of the anterior skull base and consideration of potential intracranial complications during surgical repair.

Primary Closure of Persistent Tracheocutaneous Fistula in Children

Thirty-six patients with persistent tracheocutaneous fistula (TCF) after pediatric tracheotomy were managed at Childrens Memorial Hospital in Chicago between June 1987 and July 1992. Persistent TCF was managed with surgical excision and primary closure. The mean patient age was 5 years 7 months, and the mean duration between decannulation and fistula closure was 21 months. There were no major complications and four minor complications. While most surgeons advocate other techniques, we feel that excision with primary closure is the preferred method for persistent TCF. The technique requires an airtight tracheal closure with loose closure of the peristomal soft tissue. Careful preoperative evaluation, postoperative monitoring, and wound drainage are stressed.

A bronchoscopic, computer-assisted examination of the changes in dimension of the infant tracheal lumen with changes in head position: Implications for emergency airway management

Background Resuscitation guidelines caution against extreme extension or flexion of an infants head because tracheal obstruction may occur. No data support this recommendation. The authors therefore examined the dimensions of the tracheal lumen in neutral, extended, and flexed head positions in infants undergoing general endotracheal anesthesia for elective surgery. Methods Eighteen healthy full‐term infants were studied. A flexible fiberoptic bronchoscope was passed through a previously inserted endotracheal tube and positioned above the cricoid cartilage. Video recordings were taken in each of three head positions. Recordings were analyzed by an investigator blinded to head position. A computer‐digitized technique was used to measure anterior‐posterior and lateral dimensions and cross‐sectional area. Data were analyzed using paired t tests and sign tests. Results No significant differences in mean tracheal dimensions with changes in head position were found. No infant had complete tracheal obstruction. Infants were equally as likely to have a small increase as they were to have a small decrease in tracheal dimension with changes in head position. Conclusions Despite the belief that infants and neonates have obstruction at the level of the trachea with extreme positions of the head, the authors were unable to demonstrate this phenomenon.

Visualizing the Pediatric Airway: Three-Dimensional Modeling of Endoscopic Images

Three-dimensional reconstruction of medical images has emerged as an important visualization tool for studying complex anatomy. These tools have found important applications in neurology and plastic surgery using computed tomography (CT) and magnetic resonance imaging (MRI) data. However, CT and MRI do not sufficiently delineate lesions of the pediatric airway. Inspection through the rod lens telescope remains the standard diagnostic method. A video recording of an endoscopic procedure is essentially a sequence of two-dimensional images captured as the telescope traverses the airway lumen. Using digitized endoscopic video recordings and computer graphics reconstruction techniques, we have developed a preliminary three-dimensional modeling system for the pediatric airway. A series of normal and abnormal telescopic airway examinations were video recorded. Serial sections were obtained by digitizing the video images at uniform intervals as the scope traversed the airway lumen between the vocal folds and the carina. The digitized images were calibrated and used to reconstruct the airway lumen in three dimensions. Classifying airway abnormalities according to the minimal cross-sectional area or with descriptive terms can be subjective and dependent on the endoscopists observational skills. We hope that this preliminary work will lead to more precise and understandable methods for representing complex airway lesions.

Right aortic arch, right ligamentum, absent left pulmonary artery: a rare vascular ring

A 5-month-old infant presented with respiratory failure secondary to severe right bronchial compression. Diagnostic imaging revealed a right aortic arch and absent left pulmonary artery. Surgical relief was obtained via median sternotomy by dividing a right ligamentum and pexing the enlarged right pulmonary artery to the ascending aorta.

Bilateral choanal atresia associated with nasal dermoid cyst and sinus: a case report and review of the literature.

The relationship of choanal atresia to various systemic malformations is well acknowledged by the CHARGE acronym: colobomas, heart defects, atresia choanae, retarded growth and development, genito-urinary defects, and ear defects. In the past, we have reported the finding of an isolated skull base malformation associated with choanal atresia. We report here a unique case of choanal atresia associated with a patent foramen cecum and intracranial extension of a dermoid sinus. The embryogenesis of this condition is accounted for by the mesodermal flow theory of choanal atresia formation, and implies a need for thorough imaging of the anterior skull base in cases of bilateral atresia.