Pulmonary, Critical Care & Sleep Medicine

Leadership Team

Meet Our Executive Leadership Team

John A. Belperio, MD

Division Chief

John A. Belperio, MD is the Chief and Professor of Medicine in the Division of Pulmonary, Critical Care, Sleep Medicine, Clinical Immunology and Allergy at The David Geffen School of Medicine at UCLA. Dr. Belperio completed undergraduate at Drexel University in Philadelphia with a B.S. in Chemical Engineering, Medical School at the Temple University and Residency training at The University of Maryland.

David Sayah, MD, PhD

Clinical Chief | Medical Director Lung Transplant Program

Our Leadership Team

Ravi S. Aysola, MD

Section Chief, Sleep Medicine

Dr. Ravi Aysola, MD is a critical care medicine specialist in Santa Monica, CA and has been practicing for 19 years. He graduated from University Of Texas Southwestern Medical Center At Dallas in 2000 and specializes in critical care medicine, pulmonary disease, and more.

Igor Barjaktarevic, MD, PhD

Medical Director, COPD Program | Medical Director, Liver Transplant ICU

As an intensivist in the Division of Pulmonary and Critical Care medicine, I take care of patients admitted to Medical and Liver-transplant Intensive Care Units at Ronald Reagan Medical Center and participate in education of UCLA residents and fellows. Being a Director of of Bedside ultrasound of the Department of Medicine at UCLA, my clinical and research interest is focused on ultrasound-based technologies in intensive care settings and, in particular, fluid responsiveness in shock.

Steven Y. Chang, MD, PhD

Medical Co-Director, Ronald Reagan Medical Center Medical Intensive Care Unit

Dr. Chang has expertise in the management of acute respiratory failure requiring mechanical ventilatory support, and in the management of shock. He is currently involved as a co-primary investigator in ARDS trials overseen by the PETAL network and sponsored by the NIH/NHLBI. He has been involved in multiple clinical trials investigating mechanical ventilation, septic shock, and ICU structure & function.

Colleen L. Channick, MD

Co-Director, Interventional Pulmonary Program

Dr. Colleen Channick is a nationally recognized interventional pulmonologist who provides both inpatient and outpatient care in Westwood and Santa Monica, and performs diagnostic and therapeutic procedures in both settings. She is board certified in internal medicine, pulmonary medicine and critical care medicine, and is a diplomat of the American Association of Bronchology and Interventional Pulmonology.

Richard N. Channick, MD

Co-Director, Pulmonary Vascular Disease Program | Medical Director, Acute and Chronic Thromboembolic Disease Program

Dr. Channick is Co-Director of the Pulmonary Vascular Disease Program and Director of the Acute and Chronic Thromboembolic Disease at UCLA Medical Center and is the incoming President of the PERT Consortium. Dr. Channick received his medical degree from Temple University Medical School, where he was elected to the Alpha Omega Alpha Medical Honor Society.

Patricia H. Eshaghian, MD

Medical Director, Adult Cystic Fibrosis Program

Dr. Eshaghian graduated from the Albert Einstein College of Medicine in 2002. Dr. Eshaghian works in Los Angeles, CA and 2 other locations and specializes in Pulmonary Critical Care and Pulmonary Disease. Dr. Eshaghian is affiliated with Ronald Reagan UCLA Medical Center and Santa Monica UCLA Medical Center with 17 years of experience.

Oscar A. Estrada Paz, MD

Medical Director, Santa Monica Hospital Medical Intensive Care Unit

Tao He, MD, PhD

Medical Director, San Fernando Valley Interventional Pulmonology

Dr. Tao He is a Pulmonary Disease Specialist in Santa Monica, California. He graduated with honors in 2003. Having more than 16 years of diverse experiences, especially in PULMONARY DISEASE, CRITICAL CARE (INTENSIVISTS), INTERNAL MEDICINE, Dr. Tao He affiliates with many hospitals including Santa Monica - Ucla Med Ctr & Orthopaedic Hospital, Ronald Reagan U C L A Medical Center, Los Robles Hospital & Medical Center.

Rita Kachru, MD

Section Chief, Clinical Immunology & Allergy

Dr. Rita Kachru is an allergist-immunologist in Santa Monica, California and is affiliated with multiple hospitals in the area, including UCLA Medical Center and UCLA Medical Center-Santa Monica. She received her medical degree from Medical College of Wisconsin and has been in practice for more than 20 years. Dr. Kachru accepts several types of health insurance, listed below. She also speaks multiple languages, including Spanish.

Kathryn H. Melamed, MD

Program Director, Pulmonary & Critical Medicine Fellowship

Nida Qadir, MD

Medical Co-Director, Ronald Reagan Medical Center Medical Intensive Care Unit

Allison L. Ramsey, MD

Program Director, Lung Transplant Fellowship

Rajan Saggar, MD

Co-Director, Pulmonary Vascular Disease | Program Director, Pulmonary Hypertension Program

S. Samuel Weigt, MD

Medical Director, Interstitial Lung Disease Center

Dr. Sam Weigt is an Assistant Professor in the Division of Pulmonary and Critical Care Medicine. He is also the director of the Interstitial Lung Disease Center and Pulmonary Fibrosis Foundation Care Center at UCLA. He is a graduate of Creighton University School of Medicine, where he earned his M.D. degree. He then did his residency training in Internal Medicine and fellowship in Pulmonary and Critical Care at UCLA.

Michelle R. Zeidler, MD

Program Director, Sleep Medicine Fellowship

Dr. Michelle Zeidler is a pulmonologist in Los Angeles, California and is affiliated with multiple hospitals in the area, including Cedars-Sinai Medical Center and LAC-Olive View-UCLA Medical Center. She received her medical degree from Keck School of Medicine of USC and has been in practice for more than 20 years.