Recurrent Apparent Life-Threatening By D.A. Cozzi, M. Bonanni,
F. Cozzi, M.P. Villa, and G. Polidori Rome, Italy
*An infant with repaired esophageal atresia presented with several apparent life-threatening events (ALTEs). He had upper airway instability, gastroesophageal reflux (GER), and tracheomalacia. Oxygen breathing test results showed a modest increase in arterial PO* consistent with the development of an intrapulmonary shunt from absorption collapse of some hypoventilated areas of the lung. Glossopexy was followed by improvement in upper airway stability, normal oxygen test, and disappearance of ALTE. These findings support the concept that upper airway instability, obstructive apnea, lower airway instability, absorpion collapse, massive intrapulmonary shunt, and ALTE are the result of a cascade reaction. The authors conclude that infants with ALTE associated with obstructive apnea and O2 shunting require glossopexy to reduce the risk of sudden death. Copyright o 1996 by WA Saunders Company INDEX WORDS: Esophageal esophageal reflux, obstructive gen breathing test.
Event Relieved by Glossopexy
atresia, tracheomalacia, gastroapnea, cyanotic attacks, oxy-
NE OF FIVE infants with repaired esophageal 0 atresia requires fundoplication or aortoperry in the treatment an apparent life-threatening event of
(ALTE) or severe respiratory distress.l The rationale behind surgical treatment is to prevent reflex apnea or laryngospasm caused by gastroesophageal reflux (GER),2 or airway obstruction caused by tracheomalacia.3 The rapid onset and the severity of hypoxemia found during ALTE, whether or not associated with esophageal atresia, suggests that a sudden and massive intrapulmonary right-to-left shunt may play an important pathogenetic role.4 Southall et a14.5speculated that the intrapulmonary shunt may be caused by ventilation-perfusion inequality secondary to small airway closure or alveolar hypoxia. Triggering factors include, pain, anger, reflex or obstructive apnea, abnormal pulmonary vasoconstrictor reflex, respiratory tract infection, surfactant deficiency, and GER.5 Here we report an observation that supports the view that giossoptosis may play a role in the pathogenesis of ALTE in some infants with repaired esophageal atresia.6
ALTEs occurred in 11 months. Barium esophagogram and bronchoscopy ruled out recurrent tracheoesophageal fistula and documented GER and severe tracheomalacia, which were clinically evident because of the presence of frequent vomiting and of a brassy cough, similar to the bark of a seal. Nearly all ALTEs required emergency hospital admission. Tachypnea, mild retractions, reduced air entry, and prolonged wheezing expiration were recorded. Chest films showed no lung lesions. A diagnosis of bronchiolitis had been made. Between episodes, the patient had chronic catarrh, barking cough, snoring during sleep, dyspnea with dysphonia and cyanosis during crying or agitation, profuse sweating during sleep or feeding, mild pharyngeal dysphagia, frequent vomiting, and malnutrition. At age 1 year, the infant was admitted to hospital with upper respiratory tract infectlon (URTI) and high body temperature (39°C). The following day, during feeding, he suddenly presented with crying, profuse sweatmg, cold lower limbs, cyanosis, and respiratory arrest. He was intubated, artificially ventilated, and transferred to our hospital. After a few days, the patient was weaned from the ventilator and extubated. On spontaneous ventilation, he presented with tachypnea, mild inspiratory stridor, retractions, reduced air entry, and prolonged wheezing expiration. The expiratory wheezing was loudest over the neck. The tongue size was normal. Prone position or continuous insufflation of the pharynx with a naso-pharyngeal tube were followed by reduction of retractions, improvement of air entry, and disappearance of stridor and of wheezing expiration. A skull x-ray ruled out the presence of micrognathia. Chest films showed no lung opacities. Body weight was 7.76 kg (<3rd percentile). The infant had no blood gas derangement. Percutaneous and arterial PO-, and PCO~ changes while breathing 100% oxygen were studied (Fig 1). The test showed only a moderate increase in POT and a normal Pco2 consistent with the development of a considerable right-to-left shunt caused by absorption collapse of some hypoventilated areas of the lung. A clinical diagnosis of upper airway instability was made, and the intrapulmonary airway instability was considered secondary to recurrent episodes of obstructive apnea and hypopnea. The patient was therefore submitted to glossopexy. Ten days after lip-tongue adhesion, POT changes while breathing 100% oxygen (Fig 1) were similar to our findings in normal mfants of the same age (normal values of percutaneous PO* between 400 and 500 mm Hg). In the next 13 months, this patient had no further episodes of respiratory distress during sleep, crying, or agitation and no further ALTE. The parents expressed the opinion that “he had never breathed so well in his life.” The “bark,” although still present, was much less prolonged. He had a few episodes of mild respiratory distress with desaturations during URTI. At age 22 months. a polysomnographic study during an episode of URTI documented
CASE REPORT A black Infant, born after 38 weeks’ gestation with a birth weight of 2.75 kg, had esophageal atresia with a distal tracbeoesophageal fistula that was repaired at another hospital shortly after birth. During the first 4 months of life he presented with oro-pharyngeal dysphagia, which required gavage alimentation supplemented by parenteral nutrition. At 1 month of age he started having ALTE during or after feeding. or during sleep. These episodes continued, and eight ~~/ournaiofPedratr/cSurgery,
Vol31,No12(December),1996:
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From the Pediattic Surgical Unit and Pediamc Pulmonary Unct, Policlimco Umberto I, University of Rome “La Saplenza, ” and the Pediatric Intensive Care Unit, Poklinico Gemelli, Catholic University, Rome, Italy. Address repnnt requests to F. Cozzi, MD, Head of Pediattic Surgery Policlimco Umberto I, Viale Regina Elena, 324, 00161 Rome, Italy. Copynght o 1996 by WL?. Saunders Company 0022-3468l96l31I2-0030$03 OOIO 1715
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400 mmHg
I 10 glossopexy G after glossopexy 1-o 25 30 35 -before
0
I 0
5
10
15
20
Time
(min)
Fig 1. Transcutaneous oxygen tension (TcPoJ while breathing room air and 100% oxygen. Before glossopexy, a moderate increase in TcPo, during oxygen breathing is consistent with the development of a considerable O2 intrapulmonary shunt caused by lower airway instability. Oxygen breathing test was within normal limits 10 days after glossopexy.
mild desaturations (mean desaturation, SS%) caused by a few central and obstructive apneas and numerous obstructive hypopneas. The apnea + hypopnea index was 50.1 (normal upper limit of index, 20). After 3 days, a new polysomnographic study during 0s administration showed disappearance of desaturations (mean desaturation, 94%) and a marked reduction in obstructive hypopneas (apnea + hypopnea index, 8.1). The recurrent episodes of mild respiratory distress during URTI resolved spontaneously at 2 years of age. After lip-tongue adhesion oropharyngeal dysphagia also improved, and the patient demonstrated a remarkable catch-up weight gain. His body weight was 11.5 kg (> 2Sth percentile) at age 25 months when removal of the lip-tongue adhesion was performed. The patient continued to have no feeding or respiratory problems. Glossopexy did not result in adverse sequelae with respect to speech or dentition. DISCUSSION
Upper Airway Instability and Respiratory Distress
Many infants with esophageal atresia, not unlike those with other malformations related to maldevelopment of frontonasal or branchial arch derivatives (such as choanal atresia, congenital micrognathia, or vascular ring), may present with a common syndrome caused by a maturational dysautonomia (glossoptosisapnea syndrome). 7-9The abnormal autonomic control of genioglossus and other upper airway dilating muscles results in respiratory distress caused by recurrent episodes of partial or complete upper airway obstruction. These obstructive apneas and hypopneas may be difficult to detect when, as in the present observation, they occur only during sleep or when the patient experiences an added respiratory load (URTI, supine position, crying, or excitement). The metabolic cost of the increased work of breathing, however, may become so pronounced that it results in growth failure. lo The anomalous regulation
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of other autonomic functions is responsible for additional clinical manifestations including reflex apnea or bradycardia, oro-pharyngeal dysphagia, GER, vomiting, hyperhydrosis, hyperthermia, and sialorrhea.7-9 In our patient, the association of respiratory distress with so many clinical manifestations of maturational dysautonomia strongly suggests that upper airway instability played a role in the pathogenesis of respiratory difficulties. Furthermore, we found clinical signs consistent with the diagnosis of upper airway instability. Retractions associated with inspiratory stridor and reduced or absent air entry without lung lesions on chest film are clinical manifestations of a functional inspiratory airway obstruction. The improvement in respiratory distress and stridor in the prone position or during continuous insufflation of the pharynx is considered helpful in the diagnosis of upper airway functional obstruction.7,8J1 The signs of inspiratory obstruction often associated with those of expiratory obstruction, that may be misdiagnosed as recurrent bronchiolitis or asthmatic attack, are characteristic of the respiratory distress caused by upper airway instability.7-9 The improvement in respiratory distress after glossopexy in the present patient is not surprising and indicates that a falling back of the tongue contributed to upper airway obstruction. We had previously observed that glossopexy is a valid technique used to stabilize the upper airway in another infant with repaired esophageal atresia.12 The latter infant had severe sleep-related obstructive apneas without ALTE. A great improvement in inspiratory and expiratory breathing during sleep, after glossopexy, was clearly seen in video recording.12 In addition, simultaneous pulse-oxymetry and transcutaneous monitoring of PO2 and PCOz showed that lip-tongue adhesions were followed by disappearance of severe desaturation and a return to normal of hypoxemia and hypercapnia detected during sleep before glossopexy. l2 Similar positive results have recently been documented by polysomnography performed before and after lip-tongue adhesions in infants with glossoptosisapnea syndrome associated with congenital micrognathia.13J4 Some of these infants with obstructive apnea treated with glossopexy continued, like our patient, to have mild desaturation during URTI, mainly caused by obstructive hypopneas.13 These findings indicate that an upper airway instability may be reversed, to a great extent, by gIossopexy. During the inspiratory difficulties imposed by URTI, lip-tongue adhesion helps avoid frequent episodes of complete upper airway obstruction but does not prevent recurrent
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partial glossoptotic airway obstruction until the patient reaches maturational-related stability. To further support the fact that glossopexy stabilized the upper airway we observed a catch-up weight gain in our patient after glossopexy. This is similar to that reported in infants with glossoptosis-apnea associated with congenital micrognathia following relief of functional oropharyngeal obstruction.8J0 Lower Airway Instability and AL TE
The expiratory wheezing presented by our patient was loudest over the neck, and was produced by grunting, ie, adduction of the vocal cords to brake the expiratory flow. In infants with esophageal atresia, grunting associated with inspiratory upper airway obstruction may be a compensatory mechanism in defense of lung volume or lower airway patency threatened by obstructed inspiratory breathing.’ Grunting therefore should be regarded as a sign of a lower airway instability secondary to underventilation. This concept is supported by the fact that in our patient grunting disappeared after the relief of upper airway obstruction while in the prone position, or with the use of continuous insufflation of the pharynx, or after glossopexy. Furthermore, we demonstrated a reduced increase in PO? while breathing 100% O2 in the absence of chest film or Pco, changes, which suggests the development of an intrapulmonary right-to-left shunt. Oxygen, compared with other gases, is more rapidly absorbed from the alveolus. Alveolar hyperoxia therefore converts into atelectasis those segments of the lung with a low ventilation to perfusion ratio, where the absorption exceeds the rate of delivery of OZ. The clinical corollary is that measuring PO,changes while breathing 100% oxygen is a sensitive method of identifying those patients with lower airway instability.r5 In the present infant, the lower airway instability was probably sustained by underventilation caused by recurrent episodes of glossoptosis apnea and hypopnea, as the breathing oxygen test returned to normal 10 days after glossopexy.
It is tempting to suggest that in some infants with repaired esophageal atresia many factors including URTI, sleep, crying, excitement, feeding, tracheomalacia, and GER may lead to worsening of an associated upper airway instability. The resulting obstructive apneas and hypopneas, in turn, cause in some infants widespread hypoventilated areas of the lung with a low ventilation to perfusion ratio. In these areas, a subsequent episode of reflex or obstructive apnea will further reduce the peripheral airway stability and will result in widespread small airway closure, absorption collapse, and massive shunting during expiration. In the presence of an unstable peripheral airway, the apnea and the consequent massive intrapulmonary shunt may explain the rapid onset and the severity of hypoxemia found during ALTE. These episodes may be responsible for anoxic brain damage or sudden and unexpected death.2-8 Glossopexy and AL TE
To our knowledge, the present patient is the first to have ALTE treated with glossopexy. The disappearance of ALTE after glossopexy, like that reported after aortopexy or fundoplication,2,3 may have only a temporal correlation with surgery because of a spontaneous improvement in the respiratory status. In our patient, however, polysomnography documented desaturation caused by partial upper airway obstruction up to 10 months after glossopexy. These desaturations would have been more severe without liptongue adhesion. A clinical trial to prove or disprove the outcome of this approach, however, is mandatory. We suggest that this simple procedure be considered in those infants with ALTE who present clinical manifestations of upper airway instability and a considerable right-to-left shunt during 100% oxygen breathing. Lip-tongue adhesion would play an important role in the natural resolution of ALTE by reducing the risk of anoxic brain damage or sudden death.8
REFERENCES 1. Spitz L, Kiely E, Brereton RJ: Esophageal atresia: A five year experience with 148 cases. J Pedratr Surg 22:103-108,1987 2. Leape LL, Holder TM, Franklin JD, et al: Respiratory arrest in infants secondary to gastroesophageal reflux. Pediatrics 60:924928,1977 3. Filler RM, Rossello PD, Lebowitz RL: Life-threatening anoxic spells caused by tracheal compressron after repair of esophageal atresia: Correction by surgery. J Pediatr Surg 5:7397481976 4. Southall DP, Samuels MP, Talbert DG: Recurrent cyanotrc episodes with severe arterial hypoxaemia and intrapulmonary
shunting: A mechanism for sudden death. Arch Dis Child 65:9.53961,199O 5. Poets CF, Samuels MP, Southall DP: Potential role of intrapulmonary shunting in the genesis of hypoxemic episodes in infants and young children. Pediatrics 90:385-391, 1992 6. Cozzi F: Glossoptosis as cause of apneic spells in infants with choanal atresia [letter]. Lancet 2:830-831, 1977 7. Cozzi F, Myers NA, Madonna L, et al: Esophageal atresia, choanal atresia, and dysautonomia. J Pediatr Surg 26:548-552,199l 8. Cozzi F, Pierro A: Glossoptosis-apnea syndrome in infancy. Pediatrics 75:836-843, 1985
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9. Cozzi F, Myers NA, Piacenti S, et al: Maturational dysautonomia and facial anomalies associated with esophageal atresia: Support for neural crest involvement. J Pediatr Surg 28:798-801, 1993 10. Heaf DP, Helms PJ, Dinwiddie R, et al: Nasopharyngeal airway in Pierre Robin syndrome. J Pediatr 100:698-703, 1982 il. Klein M, Reynolds LG: Relief of sleep-related oropharyngeal airway obstruction by continuous insufflation of the pharynx. Lancet 1:935-939, 1986 12. Cozzi F, Biffoni M, Bonanni M, et al: Respiratory distress relieved by glossopexy in an infant with repaired oesophageal
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atresia. Presented at the meeting of British Association of Paediatric Surgeons, Rotterdam 28 June-l July, 1994 13. Bull MJ, Givan DC, Sadove AM, et al: Improved outcome in Pierre Robin sequence: effect of multidisciplinary evaluation and management. Pediatrics 86:294-301, 1990 14. Freed G, Pearlman MA, Brown AS, et al: Polysomnographic indications for surgical intervention in Pierre Robin sequence: Acute airway management and follow-up studies after repair and take-down of tongue-lip adhesion. Cleft Palate J 25:151-155.1988 15. Dantzker DR, Wagner PD, West JB: Instability of lung units with low VA/Q ratios during 02 breathing. J Appl Physiol 38:886895,1975