Aspects of the technology described herein relate to delivery of pressure based on ultrasound data. Certain aspects relate to receiving ultrasound data collected from a subject by a wearable ultrasound device, determining that the ultrasound data indicates apnea (e.g., absence of lung sliding or movement of internal abdominal organs), and based on determining that the first ultrasound data indicates apnea, increase pressure being delivered to the subject. To increase the pressure, a positive airway pressure device may increase the pressure it generates, an adapter may route power to the positive airway pressure device, or a valve may permit air to flow from the positive airway pressure device to the subject. Increasing pressure may be triggered by an activation signal transmitted by the wearable ultrasound device or a processing device. The wearable ultrasound device may be a patch configured to couple to the subject's skin.