Leaders at Zenith and in Healthcare

dr. david pak

Dr. David Pak

Chief Executive Officer & President

Dr. David Pak has been practicing medicine as a board-certified internist for over 25 years and he still continues to enjoy seeing patients to this day. He founded Allied Institute of Medicine in 2000 which consisted of seven primary clinics, a transitional care program, wellness center primarily focused on geriatrics, hospitalists, house call program, telehealth. All service lines were sold to Humana in 2012. He went on to do consultant work for Optum and Vanguard health systems. He later became the medical director for a startup in Las Vegas to help build the Culinary Health Center. He was instrumental in recruiting all of the clinicians, developing SOPs and workflows for the internal medicine, family practice and pediatric services for the union workers for all of the major casinos. After his non-compete expired in 2018 he returned to his home in Texas.

He immediately dove back into what he loves and created ZENITH Independent Physicians Network an IPA for primary care clinicians focused on senior care in 2022. His ultimate goal is 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

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 Zenith Integrated Specialists, 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.

pedro caretta

Pedro Caretto

Director of Operations

With more than 15 years of experience as an Executive Operations and Financial Director, Pedro has been integral to strategic operational initiatives that have influenced high-percentage cost savings in Venezuela and Florida. While developing partnerships and maximizing business development efforts, he excels at negotiating and managing contracts as well as providing vendor management. 


After leading a successful business in Florida, Pedro welcomed a new opportunity in Texas as Director of Operations. In his free time, Pedro enjoys spending time with his family or enjoying the Texas scenery from his motorcycle.

tomosa ohern

Tomasa O'Hern

Business Strategist

Joining our team with over 30 years of experience in the medical field, Tomasa 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, Texas 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, Texas. Throughout the 15 years alongside her RCM, she co-owned an IT and EMR company. She moved back to Kerrville, Texas 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 reyes-broyles

Ashley Reyes-Broyles

Practice Manager

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.

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