Mercy Sleep Center is home to a team of dedicated medical professionals who specialize in sleep medicine. In addition to the physicians and medical providers, an extensive staff of sleep techs and nurses ensure each patient receives individualized and comprehensive diagnosis, treatment and follow-up care.
Mercy Sleep Center medical staff includes:
Melisa Coaker, M.A., M.D., DABSN
Melisa A. Coaker, M.A., M.D., was born and raised in the suburbs of Detroit, Mich. She completed undergraduate and graduate training at Wayne State University in Detroit. She completed medical school at Meharry Medical College in Nashville, Tenn., and finished her internal medicine residency and sleep medicine fellowship at Henry Ford Hospital in Detroit. Her special interests include sleep disordered breathing and shift work disorder, both of which were the basis for her fellowship research. She is board certified in internal medicine and sleep medicine. Melisa and her husband reside in Des Moines.
Wendy Fluegel, M.D.
Wendy L. Fluegel, M.D., born and raised in central Missouri, attended school at the University of Missouri, Kansas City. She subsequently received training in internal medicine, pulmonary, critical care and sleep medicine at the University of Minnesota in Minneapolis, where she was chief resident in internal medicine. Dr. Fluegel was an associate professor at the University of Missouri, Kansas City, in conjunction with private practice from 1995 to 1998. Research interests include alternative treatment options for obstructive sleep apnea and asthma treatment and outcome. She continues to be interested in all aspects of sleep medicine and pulmonary disorders. She is board certified in internal medicine, pulmonary and sleep medicine with board eligibility in critical care medicine.
Monica Hoffman, M.D.
Monica A. Hoffman, M.D., was born in California and grew up in Minnesota. She completed her undergraduate degree at Saint Mary’s College of Maryland and received a Master’s degree in Psychology at Old Dominion University in Norfolk, Va. Dr. Hoffman completed medical school at the University of Minnesota and finished her Internal Medicine residency at Madigan Army Medical Center in Tacoma, Wash. She completed her Sleep Medicine Fellowship at Walter Reed Army Medical Center. Dr. Hoffman is interested in all aspects of Sleep Medicine including the interaction of obstructive sleep apnea with other medical disorders as well as the evaluation and treatment of insomnia. Dr. Hoffman is board certified in Internal Medicine and Sleep Medicine.
Roger Liu, M.D.
Roger T. Liu, M.D., was born in Korea, graduated from the Korea University Medical College in 1971 and came to the United States in 1972. He completed a pulmonary diseases fellowship at Rutgers Medical School in New Brunswick, NJ, in 1978. His interests are clinical pulmonary diseases, pulmonary physiology and sleep disorders. He is board certified in internal medicine, pulmonary disease and sleep medicine.
Nguyen-Ly Vo, PA-C
Nguyen-Ly Vo, PA-C, was born in Vietnam and came to the United States with her family in 1993. They first lived in Maine, and in 1995, they relocated to Mt. Pleasant, Iowa, where she completed her secondary education. Nguyen-Ly received her Bachelor of Business Administration in Management Information Systems from the University of Iowa in Iowa City, and her Bachelor of Science in Physician Assistant Studies from Long Island University in Brooklyn, NY. She is certified by the National Commission on Certification of Physician Assistants and licensed by the state of Iowa.
Harry Yuan, D.O.
Harry Yuan, D.O., is the only pediatric sleep specialist in Iowa. He completed his pediatric pulmonology fellowship at Children’s Hospital Los Angeles and his pediatric residency at Children’s Hospital of Michigan. Dr. Yuan offers specialized care for sleep apnea and other sleep disorders in addition to pulmonary care for pediatric patients of all ages. He is board certified in pediatrics, pediatric pulmonology and board eligible in sleep medicine.