A prototype infant incubator for heliox therapy

Neonatal Applications of Heliox: A Practical Review

Heliox is a mixture of helium and oxygen that may be utilized as an alternative to air-oxygen during the ventilatory support in the neonate. Special physical properties of Heliox, particularly low density, allow for improved gas flow and diffusion. First reports of Heliox use in the pediatric population were published in 1930s; however, this therapy has never gained widespread popularity despite its described beneficial effects. Historically, this was largely due to technical challenges associated with Heliox ventilation that significantly limited its use and realization of large-scale clinical trials. However, nowadays several commercially available ventilators allow easy and safe ventilation with both conventional and non-invasive modes. In the era of minimally invasive respiratory interventions in the newborn Heliox could be seen as a therapy that may potentially decrease the risk of non-invasive ventilation failure. This review presents pathophysiologic rationale for the use of Heliox in the newborn, and summarizes available data regarding applications of Heliox in the setting of neonatal intensive care unit based on clinical studies and findings from animal models. Mechanisms of action and practical aspects of Heliox delivery are thoroughly discussed. Finally, future research directions for neonatal use of Heliox are proposed.

Prototype hybrid systems for neonatal warming: in vitro comparisons to standard of care devices

Preterm infants lack necessary thermoregulation. An ideal incubator should maintain a uniform and constant thermal environment. We compared the effectiveness of a supplemental heating blanket to improve the heating characteristics of two different incubator warming devices using assessment of their respective function alone as controls. Device A and device B, with and without a heating blanket (Harvard Apparatus), were instrumented with a distribution matrix of multiple temperature (n = 11) and humidity probes. These data were serially measured during warm up to 37.5 °C and through a series of open-door perturbations. The time constant, temperature variation, and change in air temperature were calculated. Data were analyzed for significance by 2-factor ANOVA for each respective incubator either turned on or off with either the heating blanket turned on or off. Device A warms faster (33.87% ; p < 0.05) than device B, but has a greater (37.27% ; p < 0.05) temperature variation during warmup. The heating blanket enhances the thermal response of device A during warmup, but does not alter those of device B. With the side door open, device A shows a smaller (-16.5% ; p < 0.05) temperature variation than device B; the heating blanket attenuates the temperature change in both devices. These results demonstrate that the use of a supplemental heating blanket, as well as device-related differences, may impact clinical control of a thermal environment.