Hundreds of years ago, doctors came in two varieties: physicians who diagnosed ailments and tried to treat them, and surgeons who operated on people who needed something taken out or sewn together.

Then, an explosion of new medical knowledge and treatments in the 19th and 20th centuries drove the evolution of new medical disciplines. Now, major American hospitals have specialists who focus on a single organ, a particular type of surgery, or a cluster of diseases.

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But one of the newest medical specialties evolved in the other direction.

It's called hospital medicine — and those who choose it make a conscious decision to keep their medical knowledge general, and their patient focus broad.

Their only limit: those patients must be in a hospital bed. 

Hospitalists focus on managing their medical needs and getting them ready to leave the hospital.

"We're great at being very versatile," says Vineet Chopra M.D., M.Sc., who heads the Division of Hospital Medicine at Michigan Medicine. "And we're able to look at each hospitalized patient holistically, and understand the best and shortest path for getting them from admission to discharge in a safe and efficient way."

Generalists in the hospital

Twenty years ago, hospitalists barely existed. Today, there are 44,000 of them nationwide — and they form the backbone of many hospitals' medical staffs, and the heart of research teams studying hospital care.

Michigan Medicine, for instance, hired its first hospitalist physician in 1999. Today, it has more than 104 of them caring for adult patients through the division Chopra heads, eight caring for children at C.S. Mott Children's Hospital through the Department of Pediatrics — and another 27 physician assistants and nurse practitioners who have also chosen to specialize in hospital medicine.

Together, they cared for one-third of all hospitalizations across Michigan Medicine last year.

They also took care of patients in the VA Ann Arbor Healthcare System and a special unit at the St. Joseph Mercy Ann Arbor hospital.

SEE ALSO: Doctors Who Specialize in Not Specializing: Key to Medicine's Future

Chopra notes that in this era of medical care focused on getting the most value out of every dollar, hospitalists bring a special system-level perspective. For instance, they have innovated unique platforms within which to deliver care such as the Medical Short-Stay Unit, a Michigan Medicine hospital unit for patients who need care for 48 hours or less.

There's also a chance to specialize a bit. At Michigan Medicine, some hospitalists dedicate their time to the care of hospitalized cancer patients, while others focus exclusively on transplant patients.  

Hospitalists can also help patients avoid the costly and often backlogged emergency department through short-stay observation units for patients who need a bed but perhaps not acute care.

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At teaching hospitals, hospitalists are heavily engaged in the training of internal medicine residents and medical students — at a time when those individuals may still be deciding which area to specialize in. The chance to hone their broad-based diagnostic and treatment skills alongside hospitalists is leading more to choose the field.

Hospitalists also do research that looks for trends and opportunities across many hospital units, or many hospitals – such as the Michigan Hospital Medicine Safety Consortium, which pools and analyzes data from hospitalist-run teams across the state, and drives improvements in care. U-M and Ann Arbor VA hospitalists have teamed up with others to run the Patient Safety Enhancement Program, which focuses on key risks to patients such as hospital-acquired infections.

Michigan Medicine even offers a two-year fellowship program to train hospitalists in research methods.

For physicians just finishing their training in internal medicine, working as a hospitalist can be a temporary stop — or a long-term career.

But there are tradeoffs. Hospitalists don't get to develop the long-term clinical relationships with patients that they would in an outpatient office setting.

Here's what some Michigan Medicine hospitalists had to say about their chosen profession:

"What I love about hospital medicine, and the reason I chose it, is the intense rapport and relationship we are able to have with patients in the midst of (often) difficult circumstances, in addition to the breadth of clinical knowledge and literature that a hospitalist must command to be able to treat the medical complexity that our patients at Michigan bring with them. It's a field of medicine where you make a difference, be it at the bedside of a patient, in a field of interest of your choosing or "at the table" where decisions are made." – Robert Chang, M.D.

I love being able to care for the entirety of disease — I'm not confined to treating and providing recommendations for one organ system. Some people steer away from Hospital Medicine because they worry about 'dealing with social problems,' but these problems are fundamental to the wellness of our patients and it is a privilege that as a Hospitalist I get to care for every aspect of those I meet. ­– Daniel Cronin, M.D.

"I decided to choose Hospital Medicine as a specialty because I'm skilled at caring for acutely ill patients with a wide variety of medical diseases." – Paul Grant, M.D., FACP, SFHM, director of the Medical Consultation Service and Perioperative Clinic

"I am proud to be a hospitalist because I have the opportunity to be the face of care at a time when patients are scared and vulnerable. This can be an enormous challenge, but simultaneously is an enormous privilege." – Ashwin Gupta, M.D., Section Chief Hospital Medicine at the VA Ann Arbor Healthcare System

"Hospitalists are the consummate jacks-of-all-trades, often leading their organizations in the domains of education, administration, information technology, and safe, efficient, and high-quality patient care." – Nathan Houchens, M.D., Associate Chief of Medicine, VA Ann Arbor Healthcare System

"We touch people's lives during the most vulnerable time and we have the ability to turn their distress into comfort. It's very rewarding to work within a multi-disciplinary team to provide excellent care for our patients. We are also the experts at hospital operations and it is very meaningful when we have a voice in how things are done." – Rafina Khateeb, M.D., MBA, SFHM

"I like being a hospitalist because I have formed enriching relationships with people in multidisciplinary roles, and I learn something every day." – Liana Marquis, M.D.

"I feel that a Pediatric Hospitalist is ideally positioned to optimize the experience of the hospitalized child and their families. We focus on all aspects of the inpatient stay. Most importantly, we try to always keep in mind that the most important person in the room is a child, who is often scared, confused, or just bored and determining how to help them cope with being in the hospital, whether it is for a day or a month."  – John P. Schmidt, M.D., FAAP Director, Division of Pediatric Hospitalist Medicine, C.S. Mott Children's Hospital