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Strong leaders grow strong practices

Dr. David Pak

Dr. David Pak, D.O.

Chief Executive Officer / President

Prior to opening Pak Medical Group in New Braunfels, TX, Dr. Pak enjoyed a long career of patient care, innovation, and business development. He was founder of Allied Institute of Medicine in San Antonio, TX, Regional Medical Director at Concentra Primary Care in San Antonio, TX, founder of Pak Medical Group and President of the Kaua’i Medical Association in Kaua’i, HI, and Medical Director at the Culinary Health Center in Las Vegas, NV before finally returning home to Texas where he opened the doors to New Braunfel’s beloved Pak Medical Group.

Most recently, Dr. Pak partnered with Innovista Health Solutions to co-found the Zenith Independent Physician Network, a network of primary care physicians that work to improve patient care and outcomes by ensuring each patient receives the right care, at the right time, and at the right place. When he is not burning the midnight oil or welcoming new business ventures, you can find Dr. Pak on the tennis court, or golfing with Kristy, his wife and best friend.


Kristine Pak

Chief Financial Officer

Kristine Pak is a Certified Public Accountant with over 25 years of private and public industry accounting experience. Prior to Pak Medical Group, she was the Controller of P3 Health Partners which focused on delivering patient-centered care in Nevada and Arizona. Kristy is thrilled to be back in Texas to help improve the quality of healthcare in the community she calls home. In her spare time, Kristine enjoys playing tennis and golf with family and friends.


Amanda Ward

Human Resource Director

Amanda joined Pak Medical Group in 2019 bringing with her more than 20 years of experience in healthcare. She has a Bachelor’s in Healthcare Administration from Texas State University in San Marcos, TX and a Master’s in Management and Leadership from Western Governor’s University. With an undeniable passion for patient care, her physicians and clinicians, and their incredible team of medical and administrative professionals, Amanda pours her heart into the growth and success of Pak Medical Group every day. She is a proud Texas native who enjoys spending time with her family, traveling, cooking, and spoiling her beloved Shih Tzu, Minnie.

Tomasa O'Hern | Pak Medical Group, PLLC

Tomasa O’Hern

Revenue Cycle Director

Tomasa has over 30 years of experience in the medical field and has been an entrepreneur since 1998. Alongside her husband Jerry O’hern, Tomasa has opened multiple businesses within multiple sectors of the market. Starting in 1992 working for an ophthalmologist in her hometown of Kerrville TX she grew a love for the medical field. This led her to open her first business OMB, a turnkey RCM at age of 21 in San Antonio, TX. Throughout the 15 years alongside her RCM, she co-owned an IT and EMR company. She moved back to Kerrville Tx in 2011 to be closer to family where she went on to own her restaurant and clothing boutique.

During her free time, Tomasa enjoys spending quality time with friends and family. She also enjoys spending time and going on walks with her three dogs.

Ashley Thatcher headshot grey

Ashley Thatcher (Reyes-Broyles)

Practice Administrator

Ashley is a San Antonio, TX native and graduate of John Jay High School. She started her journey in the medical field as a Certified Nursing Assistant at the age of 17. Ashley later became a Registered Medical Assistant in 2003, an LVN in 2012, and Clinical Manager in 2017. Ashley is passionate about healthcare and putting the needs of patients first. As a leader, she also has a passion for mentoring and engaging others by helping them grow and realize their potential.

Ashley is the mother of four amazing sons – two of her own and two bonus sons from her recent marriage in July of 2021. In her free time, she loves quality time with her family, travel, watching football (Go Saints), and relaxing on the lake. She also enjoys country dancing and karaoke.

PAK Medical Group

Melainie Buer

Practice Administrator

Melainie Buer joined us in November of 2021. She was born and raised in Ekalaka, Montana and moved to New Braunfels, Texas from Gillette, Wyoming. She joined us with over 25 years of healthcare experience, most recently with Campbell County Health where she spent the last 21 years in various leadership roles including Patient Access Services Supervisor and Operational Supervisor for the Campbell County Medical Group. Delivering outstanding customer service to patients as well as providers, staff, and ancillary colleagues has always been an essential part of Melainie’s work life. She prides herself in ensuring her leadership style is reflective of a positive, cohesive, and collaborative mindset.

Melainie manages the daily functions of Pak Medical Group’s multiple locations and looks forward to our continued growth including the addition of specialty service lines. Melainie proudly supports Dr. Pak’s “very compelling picture for the future of Pak Medical Group,” as she states, and she’s very excited to be a part of such a motivated and positive team with great vision and goals. She looks forward to the many positive challenges and successes to come.       

Melainie is an animal lover and advocate who enjoys landscaping, gardening, and spending time outdoors with her two Golden Retrievers – Hudson and Reser. She looks forward to making Texas her home, exploring the hill country, and soaking up the Texas music scene.         


Amy Pitzer

Business Development Director

Amy was born and raised in Sacramento, CA and moved to New Braunfels, TX in 1993. She worked for 11 years in the DME industry for a local company before deciding to stay home with her children for a year – getting one ready to graduate from high school and the other ready to start kindergarten. Once she returned to work, she entered the Home Health industry as a Professional Service Coordinator helping people obtain skilled nursing, physical therapy, and occupational therapy for their healthcare needs at home.

Amy proudly married a local New Braunfels fire fighter who is now Captain of the Fire Marshal’s Office as the lead arson investigator. They have two daughters and two granddaughters. In her free time, Amy enjoys spending time with her family including camping, and going to the beach.

PAK Medical Group

Allison Sonnenburg

Practice Manager

Allison loves being involved in patient care and being able to talk, laugh, and empathize with her patients. She is a proud Army wife and mother of two. Allison and her family have lived in Texas, North Carolina, Colorado, Maryland, and Allison’s all-time favorite – Germany. Her family loves to travel, garden, play board games, but most of all she loves a good book on a rainy day.


Veronica Harlan

Credentialing Manager

Veronica is a proud Texas native. She joined the Air Force out of High School and met her husband of more than 30 years at Hickam AFB, HI. Her husband served in the Air Force for 25 years. During their time in the military they lived in Hawaii, Germany, North Dakota, New Mexico, Texas, Oklahoma, and eventually retired in San Antonio, TX. They have a daughter who lives and works in San Antonio, and two sons in the US Army. Veronica has been in the medical billing field for more than 16 years. She loves to travel and spend time with family and friends.

Take Charge of Your Health!