Also sometimes referred to as intensivists, critical care specialists are physicians with specialized training in the diagnosis and management of life-threatening conditions, such as those that affect vital organs like the heart and lungs, those that make breathing difficult or impossible, and those that affect entire organ systems, like the renal system. Critical care specialists are typically found in a hospital's intensive care unit where they monitor patients with life-threatening conditions and make determinations as to the best course of treatment.

Radiologists help doctors get a closer look at what’s happening inside your body. If your primary care doctor wants to investigate your symptoms further, they may refer you to a radiologist to get an ultrasound or x-ray. Some radiologists specialize in mammography and breast imaging, which is who you see when you need a mammogram. A Radiologist can also determine if bones are broken or fractured after any kind of accident.Radiologists are trained to perform MRIs and CT scans, both of which are used to determine the presence of diseases or disorders and help your doctor properly diagnose you. They can detect anything from tumors, bleeding and infections to bone and muscle disorders.

An emergency physician is a doctor who is an expert in handling conditions of an urgent and extremely dangerous nature. These specialists work in the emergency room (ER) departments of hospitals where they oversee cases involving cardiac distress, trauma, fractures, lacerations and other acute conditions.Emergency physicians are specially trained to make urgent life-saving decisions to treat patients during an emergency medical crisis. These doctors diagnose and stabilize patients before they are either well enough to be discharged, or transferred to the appropriate department for long-term care.

An endocrinologist is a physician with extensive training in understanding, diagnosing and treating conditions related to the endocrine system. The endocrine system regulates the balance of hormones. Conditions of the endocrine system involve an over-abundance, or deficiency of a certain hormone. While there is a range when it comes to the amount of a hormone that is deemed normal in a human, these specialists determine whether a person's amount of hormone is indicative of a health concern.

A family practitioner is a doctor who specializes in caring for people of all ages, at all stages of life. Rather than focusing on the treatment of one disease or patient population, family practitioners are often the doctors that people see for their everyday ailments, like cold and flu or respiratory infections, and health screenings. When necessary, family practitioners will provide referrals for conditions that require the expertise of another specialist.The doctors may also provide physicals, inoculations, prenatal care, treat chronic diseases, like diabetes and asthma, and provide advice on disease prevention.

A geriatric specialist is a physician who treats the elderly population and the conditions that most commonly affect them. These doctors have special training in the effects of aging on the body and mind of a patient. Geriatric specialists treat common ailments faced by senior citizens, such as frailty, incontinence, memory problems, arthritis, senility, decreased functioning and more. In addition, geriatric specialists keep abreast of the different medications that an elderly person is prescribed to treat their more complex health issues in order to decrease adverse side effects and avoid dangerous drug interactions.

An internist is a physician who focuses on the diagnosis and treatment of conditions that affect the adult population—both acute and chronic.These doctors are often who adults see as their primary physicians because they treat a broad range of illnesses that do not require surgical or specialist interventions. They also work to help a patient maintain optimal health in order to prevent the onset of disease.In addition to treating the common cold and flu, internists also treat chronic diseases like diabetes and heart disease.

A pulmonologist is a physician who specializes in the diagnosis and treatment of conditions related to the lungs and respiratory tract.These specialists are similar to critical care specialists in that their patients often require mechanical ventilation to assist their breathing.Pulmonologists diagnose and treat patients with conditions such as asthma, cystic fibrosis, asbestosis, pulmonary fibrosis, lung cancer, COPD, and emphysema. Exposure and inhalation of certain toxic substances may also warrant the services of a pulmonologist.Some of the tools and tests pulmonologists use to diagnose a patient are a stethoscope in order to listen for abnormal breathing sounds, chest X-rays, CT scans, blood tests, bronchoscopy, and polysomnography.

A radiologist is a physician who specializes in the use of medical imaging to diagnose and treat illnesses or injuries in patients. The different types of medical imaging are X-ray, computed tomography (CT) scans, magnetic resonance imaging (MRI), ultrasound, and nuclear medicine. Radiologists are experts in these different types of tests and can advise a primary care doctor on which test is most appropriate in a specific case. These doctors also assist primary care doctors in analyzing the images produced by these tests in order to determine next steps necessary for treatment.

A rheumatologist is a physician who has received extensive training in diagnosing and treating rheumatic conditions. Rheumatic conditions involve the joints, soft tissues, autoimmune system, vascular system, and connective tissues.Some of the conditions that rheumatologists treat are rheumatoid arthritis, ankylosing spondylitis, gout, sarcoidosis, vasculitis, and lupus. These are all conditions that involve a lot of pain and make mobility difficult. Rheumatologists use medications, such as analgesics, NSAIDs, steroids, DMARDs, infliximab, and adalimumab, as well as occupational therapy, in order to decrease pain and improve a patient's quality of life.

A surgical specialist is a physician who has additional training in a specific area of surgery.The American Board of Medical Specialties acknowledges the following surgical specialties: general surgery, thoracic and cardiac surgery, colon and rectal surgery, obstetrics and gynecological surgery, neurological surgery, ophthalmic surgery, oral and maxillofacial surgery, orthopedic surgery, otolaryngological surgery, pediatric surgery, plastic surgery, urological surgery, and vascular surgery.Some procedures are performed by more than one type of specialist. Also, some surgeons may choose to specialize in specific procedures within their specialty area. For example, a plastic and maxillofacial surgeon may specialize in performing rhinoplasty procedures.