Meet Our Providers

G. Rodney Buzzas MD, MS, FACS

Surgeon, Medical Director

Dr. Buzzas was born and raised in Great Falls Montana. He received his bachelor degree, masters in molecular biology, and medical degree from Creighton University in Omaha, Nebraska. Upon completion of his surgical residency at the University of Kansas in 1998, he and his family moved to Bend.

Stephen Archer, MD, FACS

Surgeon

Dr. Stephen Archer graduated from the University of Tennessee Medical Center in 1991 and completed general surgery training at the University of Cincinnati in 1998. He completed a fellowship in minimally invasive surgery and bariatrics at Emory University in 2000 and stayed on the surgery faculty at Emory after graduation. In 2001 he moved to Central Oregon and joined Advanced Specialty Care.

D. Scott Diamond, MD, FACS

Surgeon

Dr. Diamond was raised in Pittsburgh, PA. Although his father was a prominent General, Vascular and Trauma surgeon, he initially received his BS degree in Civil Engineering and Operations Research at Princeton University. After several years of consulting work for various healthcare entities, he discovered his true calling with medicine.

Eric Davis, PA-C

Physician Assistant

Eric Davis began his medical career by obtaining an Associate degree in Medical Assisting from Mt. Hood Community College in 1994. While working as a medical assistant and orthopedic technician he continued his education at Portland State University where he earned a Bachelor degree in Science.

Nicole O'Neill, PA-C

Physician Assistant

Anatomy and physiology at the University of Oregon piqued Nicole’s interest in the medical field. After graduating with a bachelor of science she went on to spend a year of volunteer work with Health corps, a branch of AmeriCorps. Throughout the course of that year she worked at Haight-Ashbury Free Medical clinic in San Francisco doing medical assisting, HIV test counseling, and phlebotomy.

Karen Campbell, Ph.D.

Psychologist

Dr. Karen A. Campbell joined the Outpatient Behavioral Health Department at St. Charles Medical Center in Jan. 2009 and specifically works to provide behavioral health support to the St. Charles Bariatric Surgery Program. Dr. Campbell conducts patient interviews prior to bariatric surgery in order to help them meet their weight loss goals. She also works with patients on an on-going basis to ensure their surgery is a success.

Luann Lehnertz, RD, LD, CDE

Dietician/Nutritionist

Luann Lehnertz received her BS at Mankato State University in Minnesota and completed her internship at Indiana University – Purdue University Medical Center. She has worked for St. Charles Medical Center at both the Bend as well as the Redmond facilities for the past 31 years providing patients with medical nutrition therapy. As a Certified Diabetic Educator, she provides nutrition instruction to patients in the SCMC Certified Diabetes Programs and the outpatient Self-Management of Diabetes Program.