From APA: Consultation-liaison psychiatry, also known as psychosomatic medicine, is an exciting subspecialty of psychiatry that focuses on the care of patients with comorbid psychiatric and general medical conditions. Consultation-liaison psychiatry deals with the understanding and advancement of medical science, education, and the provision of healthcare for medically ill patients.
From ABMS: A psychiatrist who specializes in the diagnosis and treatment of psychiatric disorders and symptoms in complex medically ill patients. This subspecialty includes treatment of patients with acute or chronic medical, neurological, obstetrical or surgical illness in which psychiatric illness is affecting their medical care and/or quality of life; such as HIV infection, organ transplantation, heart disease, renal failure, cancer, stroke, traumatic brain injury, high-risk pregnancy and COPD, among others. Patients also may be those who have a psychiatric disorder that is the direct consequence of a primary medical condition, or a somatoform disorder or psychological factors affecting a general medical condition.