William Tollefsen, MD is the EMS and MIH Medical Director for South Shore Health. Dual-boarded in Emergency Medicine and EMS Medicine, Dr. Tollefsen works clinically as an Emergency Physician at South Shore Health in addition to his role as EMS Medical Director.

One of few physicians in the country to receive the prestigious "FAEMS" recognition, Dr. Tollefsen is also the Medical Director for OEMS Region IV, serving 61 cities and towns of the Metro-Boston EMS Council. As the current EMS Medical Director for eight municipal and three private ambulance services on the South Shore, Dr. Tollefsen interacts and provides oversight for over 400 Paramedics.

Dr. Tollefsen graduated from New York Medical College and completed residency training in Emergency Medicine at Harvard University, Brigham and Women's, and Massachusetts General Hospital. He completed a fellowship in Emergency Medical Services and Critical Care Transport at the University of Massachusetts, where he worked as an Emergency Physician and Flight Physician for UMASS LifeFlight. He completed an MBA at the Isenberg School of Management at UMASS Amherst, and holds a Master of Medical Science degree from the Boston University School of Medicine.

A former pre-hospital provider, he is actively involved in EMS system design, paramedic education and Critical Care Transport Systems. He works closely with multiple EMS, Fire and Law Enforcement agencies throughout Massachusetts.

His research interests include systems of care, resuscitation, airway management, and paramedic education.

Every patient has unique challenges and circumstance of their disease.  My goal is to provide expert care that is tailored to the patient and their family's needs.  Using advanced and proven minimally invasive techniques such as thoracoscopy, robotic and endolumenal treatments, my goal is to minimize pain and accelerate the recovery process so that patients can return to their normal lives.  For patients with cancer, a thorough workup and expedited care is important in getting treated correctly.  Lung cancer, esophageal cancer, thymomas and mediastinal cancers can be difficult to navigate.  I will shepard patients and families through the tests, consultations, and treatments needed so that patients always know that they are being cared for.  For patients with esophageal conditions such as reflux, hiatal hernias, diverticular disease, achalasia, etc., there are minimally invasive surgical options that can provide excellent symptom relief and improve the quality of their lives.  In addition, I treat the multitude of thoracic diseases including thoracic outlet issues, hyperhydrosis, chest wall disorders such as pectus, metastatic cancer issues, end stage cancer surgical therapy among others.