Effect of Altitude on Cerebral Oxygenation During Pediatric Interfacility Transport

Abstract

The objectives of this study were to determine the usefulness of cerebral oxygenation monitoring during interfacility helicopter transport of pediatric patients and to determine the effect of changes in altitude during transport on cerebral oxygenation readings in pediatric interfacility transport patients. A convenience sample of pediatric interfacility helicopter transport patients were monitored using near-infrared spectroscopy (NIRS) technology. Cerebral oxygenation numbers were collected at baseline and at cruising altitude in patients on room air, supplemental oxygen, and mechanical ventilation. Comparisons among readings were performed to determine the effect of changing altitude during helicopter transport on cerebral oxygenation. Seventeen pediatric patients were monitored at various altitudes during interfacility helicopter transport. When compared collectively, there was no difference in NIRS readings at baseline (B) and at altitude (A): B--65.9% (SD, 9.5%) versus A--65.0% (SD, 9.9%) (P = 0.06). In patients transported at greater than 5000 ft above ground level, there was a statistically significant difference in NIRS readings: B--69.2% (SD, 8.9%) versus A--66.3% (SD, 9.8%) (P < 0.001). Patients requiring mechanical ventilator support also had statistically significant differences in NIRS readings above 5000 ft above ground level: B--78.1% (SD, 5.9%) versus A--75.0% (SD, 3.5%) (P = 0.01). Cerebral oxygenation monitoring, using NIRS technology, can be used as a monitoring tool during pediatric helicopter transport. Cerebral oxygenation may change with acute changes in altitude, especially in pediatric patients requiring high levels of respiratory support. This technology has the potential to be used to monitor tissue oxygenation and possibly guide therapeutic interventions during pediatric transport.