Dr. Dragos Zanchi and Dr. Rafael Martinez have known each other for nearly 15 years, as both friends and colleagues. Together they run a private practice built to treat patients as their own family. They strive to be available for patients at all times, maintaining a highly technological practice without losing the human touch.



About Dr. Martinez When Dr. Martinez was 18 years old, his father underwent open-heart surgery. Rafael was so impressed by meeting the surgeon who had successfully treated his father that he was inspired to become a physician himself. During his medical studies, Rafael was fascinated by internal medicine...


Dragos Zanchi


About Dr. Zanchi I’ve always known that I wanted to be a doctor and help people feel better. I decided to specialize in pulmonology because what happens in the lungs is connected to all the other systems of the body. Patients come to me with lung issues, and I may find that they have a heart condition,...

Meet Dragos Zanchi


Mercedes N. Fernandez

Adult Nurse Practitioner

Mercedes N. Fernandez, a Cuba native, has lived in Tampa since 1991. Her love for medicine and making a difference in the lives of others inspired her to study medicine in Cuba. Not having been able to complete her degree before she immigrated to the United States, she set her sights to become a nurse to further her education. In 1998, she became a Registered Nurse and worked at St. Joseph’s Hospital, Tampa in Cardiac Care and Intensive Care Units for a combined fourteen years. In 2011, Mercedes received a Masters of Science in Nursing from The University of Tampa. Mercedes is a Board Certified Adult Nurse Practitioner by the American Academy of Nurse Practitioners. In addition, she is a member of Tampa Bay Advance Practice Nurses Council and American Association of Nurse Practitioners. Mercedes has been a nurse practitioner in Pulmonary Medicine and Critical Care since 2012 and has joined Pulmonary and Sleep of Tampa in 2019.

Special Interests:

Treatment of Asthma, Pneumonia, and early Lung Cancer Detection.

Personal Interests:

Mercedes loves the outdoors and enjoys traveling to learn about exciting cultures and places around the world. She is married and is a proud parent of two college students. Mercedes loves and values the time spent with friends and family.

Krista Ziesman-Weaver

Krista Ziesman-Weaver, APRN, is a graduate of The University of South Florida USF with a master’s degree in Nursing and the University of Florida UF with a Bachelor’s degree in Liberal Arts focusing on Sociology. She graduated with both Sigma Theta Tau and Golden Key Honor Society memberships. She passed her certification with AANPCP in the fall of 2015. She is a current member of the American Association of Nurse Practitioner in good standing.

Krista started her career in nursing as a patient care assistant on the neonatal floor at All Children’s Hospital currently known as John Hopkins All Children’s Hospital in St. Petersburg, Florida in 1998. She continued on from there to become a Registered Nurse in the pediatric Intensive Care Unit remaining at All Children’s Hospital Her time in the ICU unit embedded a love of critical care patients and showed her the difference that quality and attention to detail could do to alter the outcomes for severely sick and injured patients. From there on she knew what she was destined to accomplish. Her nursing journey exploded and after completing her Master’s degree and she furthered her career to include a diverse range of specialties including infertility and family practice.

Krista is a Florida native being born right here in Tampa. Her favorite pastime is spending quality time with her family and animals on her 15-acre farm. Her passion includes breeding Dutch Warmblood KWPN horses and German Shepherd dogs.

FOR APPOINTMENTS CALL (813) 490-9495 or (813) 654-8100

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