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Executive Team

Dan Miller CEO

Dan Miller, Chief Executive Officer

Dan will move from his current role as COO at Swedish Medical Center to take the position at TMCA. This new position for Dan is a reflection of the results he has achieved including the opening of a new Burn Critical Care Unit and Outpatient Clinic earlier this year. Dan also lead the development of the comprehensive cancer program allowing Swedish Medical Center to become the 3rd hospital in the country to be pancreatic cancer accredited and the 5th in the country to be lung cancer accredited by The Joint Commission. Additionally, Dan has implemented multiple neurosciences expansions, OR projects and Women’s Services renovations.

Dan moves to his role as CEO after 12 years with HCA serving in various administrative roles. He received his Bachelor of Science in Human and Organizational Development from Vanderbilt University in Nashville, Tennessee and his Masters of Science in Health Administration from Virginia Commonwealth University in Richmond, Virginia.

“I am excited and honored to be chosen as CEO of The Medical Center of Aurora,” said Dan. “I’m looking forward to working with the talented staff and physicians to continue to provide excellent patient care to the community.”

At TMCA, Dan will oversee the medical center’s four campuses, which include two freestanding ERs, and an array of services, including a Level II Trauma Center, the Rocky Mountain Heart Institute with two accredited Chest Pain Centers and a new TAVR program starting in late October, the Joint Commission Accredited Primary Stroke Center, and HealthONE Behavioral Health Services, which will include a new adolescent unit opening in 2016, among other services. Licensed for 346 beds, TMCA has 1,600 employees, over 900 physicians and cares for over 150,000 patients annually.

The Medical Center of Aurora has twice received Magnet designation for excellence in nursing services by the American Nurses Credential Center’s (ANCC) Magnet Recognition Program® (2008, 2013), was named the #4 hospital in Colorado by U.S. News & World Report (2014-2015), received recognition as a Top Performer on Key Quality Measures® by The Joint Commission (2013, 2014)and was one of only nine hospitals in the country to be recognized by the Emergency Nurses Association with a Lantern Award for excellence in emergency room care (2013).

Bryce Dehaven

Bryce Dehaven, Chief Financial Officer

Mr. Dehaven is the Chief Financial Officer at The Medical Center of Aurora; including its Main Campus, North Campus, Centennial Medical Plaza and Saddle Rock ER. He has nearly 30 years of financial leadership experience in the healthcare industry. Prior to joining TMCA/CMP in 2013, Mr. Dehaven served as CFO to Orange Park Medical Center, a 297-bed facility in Jacksonville, Fla. Before relocating to Florida, he was CFO to 3 hospitals in Independence, Mo. and San Jose, Calif.

Mr. Dehaven completed his undergraduate studies at the University of Arizona, and received his Master in Business Administration (MBA) from the University of Colorado at Denver.

Dianne McCallister

Dr. Dianne McCallister, Chief Medical Officer

Dr. McCallister joined The Medical Center of Aurora as the Chief Medical Officer (CMO) in 2013. She provides medical leadership to The Medical Center of Aurora's Main and North Campus, as well as Centennial Medical Plaza and Saddle Rock ER.

Prior to joining The Medical Center of Aurora, Dr. McCallister served as Chief Medical Officer and VP Patient Safety and Quality Systems for Porter Adventist Hospital in Denver. Before entering into these leadership roles, she practiced as a partner in large Internal Medicine groups in the Denver area. Additionally, she served as Chief Medical Resident at Presbyterian/St. Luke's Hospital and as an instructor in Internal Medicine for University of Colorado School of Medicine.

Dr. McCallister is a board certified Internal Medicine physician, with over 25 years of clinical experience. She holds an MBA from Denver University and is certified as a Green Belt in Six Sigma Process Improvement Methodology.

Ryan Simpson COO

Ryan Simpson, Chief Operating Officer

Mr. Simpson has been in hospital executive roles for 15 years and is currently Chief Operating Officer for HCA/HealthONE's Medical Center of Aurora; including its Main Campus, North Campus, Centennial Medical Plaza and Saddle Rock ER. Having started this role in June 2011, he is responsible for the daily operations of these facilities.

Prior to joining HealthONE, Ryan served in HCA's Nashville market as Chief Operating Officer for The Sarah Cannon Cancer Center and TriStar Oncology Services. Prior to this he was with Baptist Health System of East Tennessee in Knoxville, and then Middle Tennessee Medical Center (MTMC) in the chief operations role.

Ryan graduated with a B.S. in Finance and Marketing from Birmingham-Southern College, and then received his MBA and a Masters in Health Administration from the University of Alabama at Birmingham. He is a Fellow in the American College of Healthcare Executives (FACHE) and is currently a board member of the Aurora (CO) Chamber of Commerce.

Erica Rossitto CNO

Erica Rossitto, Chief Nursing Officer

Erica Rossitto, RN, BSN, MBA/HCM joined The Medical Center of Aurora as Chief Nursing Officer in November 2013. With over 10 years of nursing leadership experience, Erica oversees clinical and quality strategies for The Medical Center of Aurora and its campuses: North Campus, Centennial Medical Plaza and Saddle Rock ER.

Erica came to The Medical Center of Aurora from North Suburban Medical Center (NSMC), a HealthONE facility, where she served as CNO for 5 ½ years. Prior to her role as CNO to North Suburban Medical Center, Erica served in various nursing leadership capacities in the HealthONE system and in Louisiana.

Originally from Louisiana, Erica is a Registered Nurse, having received a Bachelor of Science in Nursing with a Minor in Psychology from McNeese State University in Lake Charles, Louisiana, where she graduated Cum Laude. She earned her Master of Business Administration/Healthcare Management from University of Phoenix in 2006.