In addition to increasing the oxygen content of the inspired gas, a nasal cannula can provide pressure (CPAP) to the infant. Locke and colleagues reported significant levels of CPAP delivery in infants exposed to flows of more than 0.5 liter/minute. This CPAP varied with nares, size, level of occlusion (secretions in nares, cannula size), and other factors; because of this, cannulas are not recommended as a CPAP delivery device. A nasal cannula may also be utilized for an infant who is cared for in a hood. This can increase the oxygen concentration of the gas delivered to the infant because the entrained gas has a higher oxygen content.