Subspecialty and Combined Training Careers

Although this section of IMpact focuses on subspecialties, it is worth emphasizing what makes internal medicine unique. Internal medicine physicians see things differently. Holistically. And in a unique way that allows them to analyze, lead, and humanize health care in a variety of different settings and roles. See all the career opportunities internal medicine can provide.

Pulmonary Disease

The Discipline

Pulmonary medicine is the subspecialty of internal medicine that focuses on the diagnosis and management of disorders of the respiratory system, including the lungs, upper airways, thoracic cavity, and chest wall. Although most common respiratory problems are treated by general internal medicine physicians and other specialty physicians, internal medicine physicians practicing pulmonary medicine (often referred to as "pulmonologists") are frequently called upon to help diagnose unknown disorders and assist in managing difficult, unusual, or complicated diseases of the respiratory system.

Pulmonologists have expertise in structural, inflammatory, infectious, and neoplastic disorders of the lung parenchyma, pleura and airways, pulmonary vascular disease and its effect on the cardiovascular system, and detection and prevention of occupational and environmental causes of lung disease. Diseases commonly evaluated and treated by pulmonologists include asthma, chronic obstructive lung disease (COPD), emphysema, lung cancer, interstitial and occupational lung diseases, complex lung and pleural infections including tuberculosis, pulmonary hypertension, and cystic fibrosis. Some pulmonologists focus on sleep-disordered breathing (such as sleep apnea) and may provide diagnostic and therapeutic services in sleep laboratories.

Some pulmonologists practice in dedicated pulmonary medicine practices or as part of a multidisciplinary group practice and provide consultative services for other physicians and follow patients with respiratory disease longitudinally. Others may work within hospitals to provide patient care and consultative services. Because pulmonologists have expertise in respiratory failure and complex interventions such as mechanical ventilation, they frequently oversee medical intensive care units in hospitals. As this role involves care of critically ill patients, training in pulmonary medicine is often coupled with training in critical care medicine. This dual training uniquely qualifies critical care pulmonologists (sometimes called "intensivists") for work in intensive care units.


For pulmonary disease training alone, a two-year fellowship is required following completion of a three-year basic internal medicine residency, after which trainees are eligible for certification in pulmonary disease through the American Board of Internal Medicine.

For combined pulmonary and critical care programs, fellowship training requires three years of training following completion of a three-year basic internal medicine residency. The American Board of Internal Medicine offers separate certificates in pulmonary disease medicine and in critical care following completion of the fellowship.

Training Positions

In this 2023-2024 academic year, there are 19 Accreditation Council for Graduate Medical Education (ACGME)-accredited training programs in pulmonary disease with 56 trainees. For combined pulmonary and critical care programs, there are 203 ACGME-accredited programs and 2,368 trainees.

Major Professional Societies

  • American College of Chest Physicians
  • American Thoracic Society

Back to the March 2024 issue of ACP IMpact