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 63-day-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.
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 . 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 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 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.
2
Case 1
A 59-day-old infant born at 34 weeks of gestation was referred to the otolaryngology service for tracheostomy 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 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 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. 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.
