Lars Knudsen is co-founder of USabcd and is chief anaesthetist and PhD at Aarhus University Hospital and helicopter emergency medical service physician at the air ambulance service of Denmark. He is a Scandinavian pioneer within the field of emergency and anesthesia ultrasound, focusing on ultrasound guided management of the airway, respiration, circulation, and vascular access. He is a faculty member on several ultrasound courses and is the co-developer of the essential emergency ultrasonography concept.