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Airway implications of congenital sternal agenesis
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American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364 – 367 www.elsevier.com/locate/amjoto
Pediatric otolaryngology: principles and practice
Airway implications of congenital sternal agenesis☆ Richard J. Vivero, MD⁎, Alexander Fort, BA, Jose W. Ruiz, MD, Soham Roy, MD Division of Pediatric Otolaryngology, Department of Otolaryngology-Head & Neck Surgery, Miller School of Medicine, University of Miami, Miami, FL, USA Received 3 February 2009
Abstract
Congenital agenesis of the sternum is an extremely unusual malformation rarely encountered by the practicing Otolaryngologist. It typically arises in conjunction with other midline ventral congenital anomalies, including abdominal, diaphragmatic, and cardiac malformations. We report a case series of two patients managed with tracheotomy placement due to prolonged intubation. The first patient was a 63day-old infant born at 34 weeks gestation with dysmorphic features, cleft lip and palate, and skeletal dysplasia, including absence of the sternum. The second patient was a 31-day-old infant born with ectopic cordis and diaphragmatic hernia. The inadequate closure of the anterior chest wall secondary to manubrium malformation or a variant contributes significantly to a child's inability to generate adequate ventilatory pressures. As a result, airway management must be considered not only to ensure airway patency but also an appropriate physiological environment to allow for adequate air exchange in the lungs. © 2010 Elsevier Inc. All rights reserved.
1. Introduction Congenital absence of the sternum is a clinical entity rarely seen in practice. It encompasses a wide range of presentations, including funnel chest with midline deformity (pectus excavatum), funnel chest with lateral deformity (pectus recurvatum lateralis), pigeon chest (pectus carinatum), bifid sternum, and complete agenesis of the sternum [1]. Complete or partial absence of the anterior chest diminishes a patient's ability to generate adequate inspiratory pressures frequently requiring long-term mechanical ventilation. We present 2 cases of sternal agenesis managed in a tertiary care setting and describe the pathophysiology, presentation, and management of this unique entity. 2. Case 1 A 59-day-old infant born at 34 weeks of gestation was referred to the otolaryngology service for tracheostomy ☆
This article was presented as an oral presentation at the annual Society of Ear, Nose, Throat Advancement in Children (SENTAC) meeting in Milwaukee, WI, December 2007. ⁎ Corresponding author. Department of Otolaryngology, Miller School of Medicine, University of Miami, P.O. Box 016960 (D48), 1666 NW 10th Ave, Miami, FL 33136, USA. E-mail address: [email protected] (R.J. Vivero). 0196-0709/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.amjoto.2009.04.010
evaluation secondary to prolonged intubation. Prior evaluation by the genetics service was consistent with short rib polydactyly syndrome with normal chromosome studies. At time of delivery, the patient was noted to have dysmorphic features with multiple congenital anomalies, including prominent occiput; short neck; low-set ears; cleft lip and palate; an omphalocele without intraabdominal content extending to sternum; sacral dimple with hair tuft; polysyndactily; short upper extremities compared to lower extremities; and skeletal dysplasia affecting the ribs, clavicles, and scapula. The patient was noted to have marginal respiratory effort at time of delivery and was initially treated successfully with an oxygen hood. On day of life 19, the patient experienced increased work of breathing with concomitant respiratory distress, necessitating intubation. Multiple attempts were made to wean the child from ventilatory support without success. On day of life 59, the child was evaluated by the pediatric otolaryngology service for possible tracheotomy placement. Physical examination was consistent with history of multiple midline abnormalities. The neck examination was significant for absence of the superior aspect of the sternum with palpable innominate artery, heart, and lung apices. The family was apprised of the high risk of performing tracheotomy in this patient given the anatomical abnormalities, and the decision was made to proceed on day of life 62. The child tolerated the procedure well with no intraoperative complications. The patient was
R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
365
Fig. 1. Congenital absence of the sternum with externalized heart.
returned to the intensive care unit for management of his medical conditions. On postoperative day 4, the patient became difficult to ventilate due to pulmonary stiffness and subsequently died due to cardiorespiratory failure. 3. Case 2 A 28-day-old infant born at 37 weeks of gestation was referred to the otolaryngology service for tracheotomy placement secondary to prolonged intubation. Prenatal evaluation showed ectopic cordis and pulmonic stenosis. On delivery, the patient was noted to have a midline defect with partial exposure of the heart, partially absent sternum, decreased bilateral reflexes, decreased muscle tone, and poor respiratory effort. A 2-dimensional echocardiogram of the heart demonstrated a moderate atrial septal defect and possible small to moderate outlet ventral septal defect. At 7 hours of age, the patient was transferred to the operating room by the cardiothoracic surgery service for intubation and management of the chest wall defect. The primary sternal defect was closed with Gore-Tex patch (W.L. Gore & Associates, Flagstaff, AZ), and advancement flaps from
Fig. 2. Anterior chest wall defect status postrepair with Gore-Tex material.
Fig. 3. Advancement skin flaps to cover previous midline defect and Gore-Tex.
bilateral axilla were created to allow for primary closure of the skin defect (Figs. 1-`4; Video 1). The patient was subsequently transferred to the pediatric intensive care unit. On day 28, the child was evaluated by the pediatric otolaryngology service for possible tracheotomy placement secondary to the patient's inability to generate adequate ventilatory pressures and prolonged vent dependence. Careful examination of the neck was significant for absence of the sternal notch and palpable innominate artery and heart.
Fig. 4. Axial computerized tomographic image with intravenous contrast status postrepair demonstrating sternal defect with greatest transverse diameter of 8 cm and a thin layer of cutaneous tissue and Gore-Tex covering the heart. There is elevation of the left hemidiaphragm.
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R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
The family was counseled on the increased risk of tracheotomy the following day. Intraoperative findings included evidence of mild subglottic edema with otherwise normal trachea. There were no intraoperative complications. The patient was returned to the pediatric intensive care unit for further management and discharged on day 98. The patient is now 1 year 8 months old and living at home. He is currently being cycled for 3 hours off the ventilator and 1 hour on the ventilator during the day with ventilator dependence at night and tolerating it well.
4. Discussion Congenital absence of the sternum results from aberrant in utero development. During the course of normal development, 2 bands of somatopleural mesenchyme appear at 6 weeks of gestation, evolve into cartilaginous bars by 7 weeks, and culminate in cranial (manubrium) to caudal (xiphoid) fusion by 10 weeks [2]. Concurrently, the ribs grow posterior to anterior from the vertebrae. Ossification centers are present in the manubrium initially then in the body of the sternum by birth [2,3]. Current theories suggest that sternal agenesis may be due to metabolic deficiencies or genetic abnormalities. Warkany et al [4], in a study of nutritionally deficient rats, notes that riboflavin deficiency is teratogenic during gestational days 13 and 14 inhibiting development of the membranous and mesenchymal skeleton. Similarly, Haque [5] provides additional anecdotal evidence of a malnourished nomadic woman with possible riboflavin deficiency who gave birth to a child with sternal agenesis. Haque [5] further advanced this argument in a series of 6 patients with a strong degree of suspicion for a nutritional deficiency as a cause. Further review of the patients, however, suggests that a genetic etiology may be of greater interest. Only one mother was noted to be clearly malnourished, and 2 children were noted to have convulsions that ceased after administration of pyridoxine suggesting a nutritional deficiency. Of the 6 children, 3 were offsprings of first-degree cousins, and 2 of the 3 offsprings of related parents were siblings, which is suggestive of possible genetic inheritance. Haque [5] notes this pattern is suggestive of autosomal recessive inheritance with variable penetrance. Cantrell's pentad, a constellation of midline abnormalities, including a defect in the lower sternum, congenital intracardiac abnormality, a pericardial defect, anterior diaphragmatic deficiency, and omphalocele, supports a midline developmental error with variable expression [6-8]. Cantrell's pentad is attributed to a failure of ventral migration of sternal anlagen and of myotomes with or without neural tube defects [8]. In our series, there is no known evidence of prior familial congenital defects or known metabolic deficiencies to clearly support either theory at this time. Our patient in case 1 has multiple midline abnormalities most suggestive of a genetic cause. Congenital absence or incomplete development of the sternum can have dire consequences if not repaired.
Respiration or gas exchange is predicated on the patient's ability to generate adequate ventilatory pressures and provide a permeable membrane for gas exchange. Although the latter is not directly affected by maldevelopment of the sternum, normal respiratory physiology involves negative intrathoracic pressure and chest excursion during inspiration and positive intrathoracic pressure and sternal incursion during expiration [9]. The sternum acts as a critical scaffold for the attachment of the ribs and associated muscles that are required for changing the dynamic size of the thorax. The resulting decreased cross-sectional area of the thorax results in a paradoxical breathing pattern with inspiration causing chest incursion and expiration causing chest excursion, which ultimately disrupts ventilation and the surface area for respiration. As the defect widens with age, respiration is further compromised resulting in distress and the need for ventilator dependence. The surgical repair of sternal agenesis has been successfully documented in a limited number of publications. Clinical management is directly related to the size of the defect and its effect on the patient's ability to ventilate. There are a number of different approaches described in the cardiothoracic literature ranging from primary closure with direct approximation of rib ends, an autogenous graft or synthetic material to fill wider gaps, a pectoral fasciorrhaphy, or a free flap reconstruction using rectus abdominus muscle [10]. From the otolaryngologist's perspective, airway management is critical. Patients, regardless of repair status, may require prolonged periods of intubation until ventilatory pressures can be self-generated. As a result, tracheostomy is critical. A tracheostomy itself presents an increased risk because of exposure of the brachiocephalic (innominate) artery, the subclavian artery, and cardiac structures including the heart and proximal aorta. These anatomical exposures increase surgical risk and the long-term risk of a tracheoinnominate fistula. The congenital absence of a sternum is a rare occurrence and infrequently reported, further hindering the development of an effective technique for management of the airway.
5. Conclusion Sternal agenesis is a rare clinical phenomenon that results in paradoxical breathing with poor ventilatory pressures. The clinical management of each patient is determined by the severity of the sternal defect. Inadequate ventilatory pressures result in ventilator dependence necessitating a tracheostomy. Tracheostomy, although routine, is of greater risk in this patient population due to the absence of bony protection provided by the sternum, which increases the risk of regional injury and tracheoinnominate fistula. The rarity of this illness coupled with infrequent reporting in the otolaryngology literature undermines the development of an effective algorithm for management of the pediatric airway in the context of sternal agenesis.
R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
Acknowledgments We thank Eliot Rosenkranz, MD, for his assistance in preparing this manuscript. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j. amjoto.2009.04.010.
References [1] Martin LW, Helmsworth JA. The management of congenital deformities of the sternum. JAMA 1962;179:82-4. [2] O'Rahilly R, Muller F. Human embryology and teratology. 3rd ed. New York: Wiley; 2001. p. 274-5.
367
[3] Haque KN, Zaidi MH. Congenital absence of sternum in a newborn infant, and its possible aetiology. Trans R Soc Trop Med Hyg 1980;74: 266. [4] Warkany J, Nelson RC. Skeletal abnormalities in offspring of rats reared on deficient diets. Anat Rec 1941;79:83-8. [5] Haque KN. Isolated asternia: an independent entity. Clin Genet 1984; 25:362-5. [6] Toyama WM. Combined congenital defects of the anterior abdominal wall, sternum, diaphragm, pericardium, and heart: a case report and review of the syndrome. Pediatrics 1972;50:778-92. [7] Spitz L, Bloom R, Milner S, et al. Combined anterior abdominal wall, sternal, diaphragmatic, pericardial, and intracardiac defects: a report of five cases and their management. J Pediatr Surg 1975;10: 491-6. [8] Cottrill CM, Tamaren J, Hall B. Sternal defects associated with congenital pericardial and cardiac defects. Cardiol Young 1998;8: 100-4. [9] Hlastala MP, Berger AJ. Physiology of respiration. New York: Oxford University Press; 2001. p. 35-8. [10] Cardoso E, Sundararajan MS. Asternia with aplasia cutis: a method of repair. Thorax 1987;42:829-30.
American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364 – 367 www.elsevier.com/locate/amjoto
Pediatric otolaryngology: principles and practice
Airway implications of congenital sternal agenesis☆ Richard J. Vivero, MD⁎, Alexander Fort, BA, Jose W. Ruiz, MD, Soham Roy, MD Division of Pediatric Otolaryngology, Department of Otolaryngology-Head & Neck Surgery, Miller School of Medicine, University of Miami, Miami, FL, USA Received 3 February 2009
Abstract
Congenital agenesis of the sternum is an extremely unusual malformation rarely encountered by the practicing Otolaryngologist. It typically arises in conjunction with other midline ventral congenital anomalies, including abdominal, diaphragmatic, and cardiac malformations. We report a case series of two patients managed with tracheotomy placement due to prolonged intubation. The first patient was a 63day-old infant born at 34 weeks gestation with dysmorphic features, cleft lip and palate, and skeletal dysplasia, including absence of the sternum. The second patient was a 31-day-old infant born with ectopic cordis and diaphragmatic hernia. The inadequate closure of the anterior chest wall secondary to manubrium malformation or a variant contributes significantly to a child's inability to generate adequate ventilatory pressures. As a result, airway management must be considered not only to ensure airway patency but also an appropriate physiological environment to allow for adequate air exchange in the lungs. © 2010 Elsevier Inc. All rights reserved.
1. Introduction Congenital absence of the sternum is a clinical entity rarely seen in practice. It encompasses a wide range of presentations, including funnel chest with midline deformity (pectus excavatum), funnel chest with lateral deformity (pectus recurvatum lateralis), pigeon chest (pectus carinatum), bifid sternum, and complete agenesis of the sternum [1]. Complete or partial absence of the anterior chest diminishes a patient's ability to generate adequate inspiratory pressures frequently requiring long-term mechanical ventilation. We present 2 cases of sternal agenesis managed in a tertiary care setting and describe the pathophysiology, presentation, and management of this unique entity. 2. Case 1 A 59-day-old infant born at 34 weeks of gestation was referred to the otolaryngology service for tracheostomy ☆
This article was presented as an oral presentation at the annual Society of Ear, Nose, Throat Advancement in Children (SENTAC) meeting in Milwaukee, WI, December 2007. ⁎ Corresponding author. Department of Otolaryngology, Miller School of Medicine, University of Miami, P.O. Box 016960 (D48), 1666 NW 10th Ave, Miami, FL 33136, USA. E-mail address: [email protected] (R.J. Vivero). 0196-0709/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.amjoto.2009.04.010
evaluation secondary to prolonged intubation. Prior evaluation by the genetics service was consistent with short rib polydactyly syndrome with normal chromosome studies. At time of delivery, the patient was noted to have dysmorphic features with multiple congenital anomalies, including prominent occiput; short neck; low-set ears; cleft lip and palate; an omphalocele without intraabdominal content extending to sternum; sacral dimple with hair tuft; polysyndactily; short upper extremities compared to lower extremities; and skeletal dysplasia affecting the ribs, clavicles, and scapula. The patient was noted to have marginal respiratory effort at time of delivery and was initially treated successfully with an oxygen hood. On day of life 19, the patient experienced increased work of breathing with concomitant respiratory distress, necessitating intubation. Multiple attempts were made to wean the child from ventilatory support without success. On day of life 59, the child was evaluated by the pediatric otolaryngology service for possible tracheotomy placement. Physical examination was consistent with history of multiple midline abnormalities. The neck examination was significant for absence of the superior aspect of the sternum with palpable innominate artery, heart, and lung apices. The family was apprised of the high risk of performing tracheotomy in this patient given the anatomical abnormalities, and the decision was made to proceed on day of life 62. The child tolerated the procedure well with no intraoperative complications. The patient was
R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
365
Fig. 1. Congenital absence of the sternum with externalized heart.
returned to the intensive care unit for management of his medical conditions. On postoperative day 4, the patient became difficult to ventilate due to pulmonary stiffness and subsequently died due to cardiorespiratory failure. 3. Case 2 A 28-day-old infant born at 37 weeks of gestation was referred to the otolaryngology service for tracheotomy placement secondary to prolonged intubation. Prenatal evaluation showed ectopic cordis and pulmonic stenosis. On delivery, the patient was noted to have a midline defect with partial exposure of the heart, partially absent sternum, decreased bilateral reflexes, decreased muscle tone, and poor respiratory effort. A 2-dimensional echocardiogram of the heart demonstrated a moderate atrial septal defect and possible small to moderate outlet ventral septal defect. At 7 hours of age, the patient was transferred to the operating room by the cardiothoracic surgery service for intubation and management of the chest wall defect. The primary sternal defect was closed with Gore-Tex patch (W.L. Gore & Associates, Flagstaff, AZ), and advancement flaps from
Fig. 2. Anterior chest wall defect status postrepair with Gore-Tex material.
Fig. 3. Advancement skin flaps to cover previous midline defect and Gore-Tex.
bilateral axilla were created to allow for primary closure of the skin defect (Figs. 1-`4; Video 1). The patient was subsequently transferred to the pediatric intensive care unit. On day 28, the child was evaluated by the pediatric otolaryngology service for possible tracheotomy placement secondary to the patient's inability to generate adequate ventilatory pressures and prolonged vent dependence. Careful examination of the neck was significant for absence of the sternal notch and palpable innominate artery and heart.
Fig. 4. Axial computerized tomographic image with intravenous contrast status postrepair demonstrating sternal defect with greatest transverse diameter of 8 cm and a thin layer of cutaneous tissue and Gore-Tex covering the heart. There is elevation of the left hemidiaphragm.
366
R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
The family was counseled on the increased risk of tracheotomy the following day. Intraoperative findings included evidence of mild subglottic edema with otherwise normal trachea. There were no intraoperative complications. The patient was returned to the pediatric intensive care unit for further management and discharged on day 98. The patient is now 1 year 8 months old and living at home. He is currently being cycled for 3 hours off the ventilator and 1 hour on the ventilator during the day with ventilator dependence at night and tolerating it well.
4. Discussion Congenital absence of the sternum results from aberrant in utero development. During the course of normal development, 2 bands of somatopleural mesenchyme appear at 6 weeks of gestation, evolve into cartilaginous bars by 7 weeks, and culminate in cranial (manubrium) to caudal (xiphoid) fusion by 10 weeks [2]. Concurrently, the ribs grow posterior to anterior from the vertebrae. Ossification centers are present in the manubrium initially then in the body of the sternum by birth [2,3]. Current theories suggest that sternal agenesis may be due to metabolic deficiencies or genetic abnormalities. Warkany et al [4], in a study of nutritionally deficient rats, notes that riboflavin deficiency is teratogenic during gestational days 13 and 14 inhibiting development of the membranous and mesenchymal skeleton. Similarly, Haque [5] provides additional anecdotal evidence of a malnourished nomadic woman with possible riboflavin deficiency who gave birth to a child with sternal agenesis. Haque [5] further advanced this argument in a series of 6 patients with a strong degree of suspicion for a nutritional deficiency as a cause. Further review of the patients, however, suggests that a genetic etiology may be of greater interest. Only one mother was noted to be clearly malnourished, and 2 children were noted to have convulsions that ceased after administration of pyridoxine suggesting a nutritional deficiency. Of the 6 children, 3 were offsprings of first-degree cousins, and 2 of the 3 offsprings of related parents were siblings, which is suggestive of possible genetic inheritance. Haque [5] notes this pattern is suggestive of autosomal recessive inheritance with variable penetrance. Cantrell's pentad, a constellation of midline abnormalities, including a defect in the lower sternum, congenital intracardiac abnormality, a pericardial defect, anterior diaphragmatic deficiency, and omphalocele, supports a midline developmental error with variable expression [6-8]. Cantrell's pentad is attributed to a failure of ventral migration of sternal anlagen and of myotomes with or without neural tube defects [8]. In our series, there is no known evidence of prior familial congenital defects or known metabolic deficiencies to clearly support either theory at this time. Our patient in case 1 has multiple midline abnormalities most suggestive of a genetic cause. Congenital absence or incomplete development of the sternum can have dire consequences if not repaired.
Respiration or gas exchange is predicated on the patient's ability to generate adequate ventilatory pressures and provide a permeable membrane for gas exchange. Although the latter is not directly affected by maldevelopment of the sternum, normal respiratory physiology involves negative intrathoracic pressure and chest excursion during inspiration and positive intrathoracic pressure and sternal incursion during expiration [9]. The sternum acts as a critical scaffold for the attachment of the ribs and associated muscles that are required for changing the dynamic size of the thorax. The resulting decreased cross-sectional area of the thorax results in a paradoxical breathing pattern with inspiration causing chest incursion and expiration causing chest excursion, which ultimately disrupts ventilation and the surface area for respiration. As the defect widens with age, respiration is further compromised resulting in distress and the need for ventilator dependence. The surgical repair of sternal agenesis has been successfully documented in a limited number of publications. Clinical management is directly related to the size of the defect and its effect on the patient's ability to ventilate. There are a number of different approaches described in the cardiothoracic literature ranging from primary closure with direct approximation of rib ends, an autogenous graft or synthetic material to fill wider gaps, a pectoral fasciorrhaphy, or a free flap reconstruction using rectus abdominus muscle [10]. From the otolaryngologist's perspective, airway management is critical. Patients, regardless of repair status, may require prolonged periods of intubation until ventilatory pressures can be self-generated. As a result, tracheostomy is critical. A tracheostomy itself presents an increased risk because of exposure of the brachiocephalic (innominate) artery, the subclavian artery, and cardiac structures including the heart and proximal aorta. These anatomical exposures increase surgical risk and the long-term risk of a tracheoinnominate fistula. The congenital absence of a sternum is a rare occurrence and infrequently reported, further hindering the development of an effective technique for management of the airway.
5. Conclusion Sternal agenesis is a rare clinical phenomenon that results in paradoxical breathing with poor ventilatory pressures. The clinical management of each patient is determined by the severity of the sternal defect. Inadequate ventilatory pressures result in ventilator dependence necessitating a tracheostomy. Tracheostomy, although routine, is of greater risk in this patient population due to the absence of bony protection provided by the sternum, which increases the risk of regional injury and tracheoinnominate fistula. The rarity of this illness coupled with infrequent reporting in the otolaryngology literature undermines the development of an effective algorithm for management of the pediatric airway in the context of sternal agenesis.
R.J. Vivero et al. / American Journal of Otolaryngology–Head and Neck Medicine and Surgery 31 (2010) 364–367
Acknowledgments We thank Eliot Rosenkranz, MD, for his assistance in preparing this manuscript. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j. amjoto.2009.04.010.
References [1] Martin LW, Helmsworth JA. The management of congenital deformities of the sternum. JAMA 1962;179:82-4. [2] O'Rahilly R, Muller F. Human embryology and teratology. 3rd ed. New York: Wiley; 2001. p. 274-5.
367
[3] Haque KN, Zaidi MH. Congenital absence of sternum in a newborn infant, and its possible aetiology. Trans R Soc Trop Med Hyg 1980;74: 266. [4] Warkany J, Nelson RC. Skeletal abnormalities in offspring of rats reared on deficient diets. Anat Rec 1941;79:83-8. [5] Haque KN. Isolated asternia: an independent entity. Clin Genet 1984; 25:362-5. [6] Toyama WM. Combined congenital defects of the anterior abdominal wall, sternum, diaphragm, pericardium, and heart: a case report and review of the syndrome. Pediatrics 1972;50:778-92. [7] Spitz L, Bloom R, Milner S, et al. Combined anterior abdominal wall, sternal, diaphragmatic, pericardial, and intracardiac defects: a report of five cases and their management. J Pediatr Surg 1975;10: 491-6. [8] Cottrill CM, Tamaren J, Hall B. Sternal defects associated with congenital pericardial and cardiac defects. Cardiol Young 1998;8: 100-4. [9] Hlastala MP, Berger AJ. Physiology of respiration. New York: Oxford University Press; 2001. p. 35-8. [10] Cardoso E, Sundararajan MS. Asternia with aplasia cutis: a method of repair. Thorax 1987;42:829-30.