The Bilevel (VPAP) ST is basically similar to the Bilevel (VPAP) S device. It gives constant IPAP (Inspiratory Positive Airway Pressure) and EPAP (Expiratory Positive Airway Pressure) in two systems. Unlike each other, the respiratory frequency can be adjusted. In this way, the patient stays above the determined respiration continuously.

ST= includes the spontaneous-timed feature. The patient should be breathing spontaneously, but the respiratory frequency number should be adjustable by the device. The BPAP-ST device should be tried in cases whose respiration is not regulated by BPAP, where higher pressure treatment is required, and especially in the presence of central apneas. In addition to the diagnosis of Obstructive Sleep Apnea Syndrome, it is indicated for use in patients with a pathology that causes alveolar hypoventilation such as restrictive lung disease, COPD, obesity-hypoventilation syndrome, sleep-related hypoventilation/hypoxemic syndrome, when spontaneous breathing and insufficient triggering power are determined.