Respiration-related cerebral blood flow variability increases during control-mode non-invasive ventilation in normovolemia and hypovolemia.

Controlling respiration in awake healthy humans reduced HR variability and increased CBF variability in hypovolemia and normovolemia. We suggest respiration-induced HR variability to be a mechanism in CBF regulation. Maintaining spontaneous respiration in patients receiving ventilatory support may be beneficial also for cerebral circulatory purposes.