Assessment of pulmonary mechanics and breathing patterns during posturally induced glossoptosis in infants

Pathogenesis of apparent life-threatening events in infants with esophageal atresia

Many infants with a repaired esophageal atresia (EA) undergo fundoplication, aortopexy, or glossopexy because the mechanisms most responsible for airway obstruction and/or apparent life-threatening event (AO/ALTE) syndrome are considered to be gastroesophageal reflux (GER), tracheal compression (TC), or obstructive apnea, respectively. In the present study, we investigated whether these mechanisms are independent or interrelated. We developed a database of 120 consecutive patients with EA treated by the senior author between 1967-2002. We studied the clinical manifestations of patients with a cervical esophagostomy and/or blind lower esophageal stump, which ruled out TC and/or proximal esophageal GER as a mechanism for AO/ALTE. Of 25 neonates who underwent section/ligation of lower tracheo-esophageal fistula and/or feeding gastrostomy, 10 critically ill neonates died. Of 15 survivors, 9 infants had a feeding gastrostomy without an esophagostomy. Of these, 6 infants presented one or more episodes of AO, and 8 presented ALTE with or without AO. Subsequently, 5 of the 9 infants underwent an esophagostomy. Eventually, 11 infants had a feeding gastrostomy with an esophagostomy. Of the latter, 5 infants presented one or more episodes of AO, and 6 presented ALTE without AO. In conclusion, oral feeding, proximal esophageal GER, and TC are not essential for AO/ALTE syndrome to occur. They are probably factors which offer evidence of an underlying problem with control of upper airway patency.

Effect of pacifier use on oral breathing in healthy newborn infants

We tested the hypothesis that the use of a pacifier may affect the ability of some term infants to maintain effective oral breathing during prolonged nasal occlusion. Three nasal occlusion tests without a pacifier and 3 with a pacifier were alternately carried out in 20 healthy term infants (age 2-5 days). Once the infant commenced oral breathing, nasal occlusion was continued for up to 90 sec (prolonged nasal occlusion), provided the infant did not start crying and that arterial oxygen saturation (SaO(2)) did not drop to < or = 80%. The response to nasal occlusion was considered maladaptive if oral breathing was accomplished with signs of upper airway obstruction. After nasal occlusion, the infants succeeded in starting oral breathing in all instances after a delay which was strongly correlated to the drop in SaO(2) (P < 0.001). Once the infants commenced oral breathing, 17/20 infants presented a maladaptive response to 62% of all tests without pacifier, whereas 10/20 infants presented a maladaptive response to 30% of all tests with a pacifier in place (P < 0.001). Following prolonged nasal occlusion, 18 of 19 infants presented a maladaptive response to 84% of all tests without pacifier, whereas 12 of 19 infants presented a maladaptive response to 41% of all tests with a pacifier in place (P < 0.001). Thus, after prolonged nasal occlusion with or without pacifier, the drop in mean SaO(2) from baseline values changed in accordance with an appropriate and maladaptive response (-4 +/- 1 vs. -7 +/- 1; P < 0.001). We conclude that normal term infants often present with a maladaptive response to prolonged nasal occlusion. The use of a pacifier enhances the infant's ability to maintain a more adequate oral air flow.