Central postoperative depression of ventilation in a full-term neonate is most likely to occur after surgery for which condition?

Central postoperative depression of ventilation in a full-term neonate is most likely to occur after surgery for which condition?

• A. Gastroschisis
• B. Omphalocele
• C. Tracheoesophageal fistula
• D. Pyloric stenosis

Answer: (D)

The situation tests how preexisting electrolyte disturbances can blunt the neonate’s central respiratory drive after anesthesia. In pyloric stenosis, prolonged vomiting causes loss of hydrogen and chloride with volume depletion, leading to hypochloremic, hypokalemic metabolic alkalosis. Alkalosis shifts the brain’s chemoreceptor response, reducing the ventilatory drive to CO2. When these infants undergo pyloromyotomy and then receive postoperative anesthesia/sedation, this blunted central drive can produce central depression of ventilation or apnea. The other conditions don’t produce that same preoperative metabolic alkalosis that dampens the central respiratory response. TEF repair carries airway and pulmonary‑mechanical risks, but not the same alkalosis‑driven central ventilatory depression. Gastroschisis and omphalocele are primarily abdominal defects whose postoperative ventilation issues relate more to respiratory mechanics than to a central depressant effect from electrolyte disturbances.

The situation tests how preexisting electrolyte disturbances can blunt the neonate’s central respiratory drive after anesthesia. In pyloric stenosis, prolonged vomiting causes loss of hydrogen and chloride with volume depletion, leading to hypochloremic, hypokalemic metabolic alkalosis. Alkalosis shifts the brain’s chemoreceptor response, reducing the ventilatory drive to CO2. When these infants undergo pyloromyotomy and then receive postoperative anesthesia/sedation, this blunted central drive can produce central depression of ventilation or apnea.

The other conditions don’t produce that same preoperative metabolic alkalosis that dampens the central respiratory response. TEF repair carries airway and pulmonary‑mechanical risks, but not the same alkalosis‑driven central ventilatory depression. Gastroschisis and omphalocele are primarily abdominal defects whose postoperative ventilation issues relate more to respiratory mechanics than to a central depressant effect from electrolyte disturbances.