When patients undergo treatments, procedures, or checkups, they have the option of receiving health care services in inpatient or outpatient care centers. A key aspect of comparing inpatient vs. outpatient care includes understanding the definition of each.

Inpatient care describes treatments and procedures that require observation of the patient by physicians, clinicians, or other medical professionals over a number of days. Patients stay at inpatient care facilities such as hospitals overnight. Amid the current pandemic, inpatient care remains critical for COVID-19 patients with respiratory issues that require the use of life-saving respirators over many days — even weeks and months.

Outpatient centers are typically used by patients undergoing treatments and medical procedures that do not require overnight stays. The shift away from inpatient services helps ensure that resources are available for those with the most severe symptoms.

Inpatient care refers to medical services that require a patient to be admitted by a doctor into a hospital or other health care facility so they can stay overnight for medical observation. Inpatient care patients typically have serious conditions or are recovering from life-threatening traumas that require monitoring by physicians or nurses over more than one day.

For a patient to receive inpatient status, a doctor must make the request. However, the process does not merely involve a doctor or hospital signoff. Guidelines published in the Medicare Benefit Policy Manual help health care providers determine which patients should be given inpatient status. According to the guidelines, not every patient who stays more than one day is considered inpatient. Some receive observation status, which, according to Verywell Health, can be more costly than inpatient care services.

When it is not necessary, avoiding inpatient care can result in significant cost savings for the party responsible for paying the cost of care — for example, the patient’s insurance plan. Even so, patients may opt for inpatient services in certain instances despite the costs, such as when they are undergoing substance abuse disorder rehabilitation or managing clinically complex problems such as Alzheimer’s disease. These patients can receive the necessary care in long-term facilities that provide physical, cognitive, and emotional well-being and psychological support.

Types of inpatient care include the following:

• Childbirth. Labor can take anywhere from an hour to more than a day. Sometimes, a cesarean section is required to help ensure both the mother’s and the newborn’s safety, which requires an overnight stay for observation.
• Complex surgeries. From organ transplantation to bypass surgeries of the heart or gastric organs, complicated surgeries require recovery and observation over several days under the watchful eyes of medical professionals.
• Serious health issues. Patients with serious health issues need constant monitoring from health care professionals. Examples of severe health issues include patients with severe respiratory problems that require intubation, those experiencing seizures from brain damage, and those in comas.

Various types of facilities can provide inpatient care. Examples include:

• Acute care facilities. These facilities typically provide inpatient medical care for short-term illness and acute conditions, as well as surgery services for injuries.
• Rehabilitation centers. Patients recovering from a stroke or brain injury may require intensive medical care in an inpatient rehabilitation facility.
• Addiction treatment facilities. From drug abuse to alcoholism, addiction treatment facilities offer around-the-clock medical care and emotional support, and keep patients safe from exposure to outside triggers.
• Psychiatric hospitals. Brain injury, intense depression, and other mental disorders can lead to self-harm. Psychiatric hospitals provide inpatient care to reduce suicidal risks and provide treatment in safe environments.
• Long-term care facilities. Long–term care facilities, including nursing homes, skilled nursing facilities, and assisted living facilities, help people unable to care for themselves with medical and personal care services.

Inpatient care is designed to treat conditions that require the patient to stay at least one night in a care-related facility. Several facility types fall under this category, including acute care facilities, rehabilitation centers, addiction treatment facilities, psychiatric hospitals, and long-term care facilities.

These resources provide more details about inpatient care facilities, including inpatient care costs, types of patient care services, and tools for patients and health care practitioners.

• This American Society of Health-Systems Pharmacists resource written for pharmacists provides information about inpatient care practitioners.
• Becker’s Hospital Review offers figures about expenses in inpatient care across 50 states.
• The Centers for Disease Control and Prevention (CDC) provides health care systems and facilities with guidance on the use of inpatient care during the pandemic.
• Mental Health America provides information about inpatient mental health treatment services.
• This glossary of health care terms is from the Centers for Medicare and Medicaid Services (CMS).
• These resources from the CDC regarding long–term care facilities include fact sheets for clinical staff, checklists, and training tools.

Outpatient care describes any medical procedure or treatment that does not require a patient to stay overnight. When considering inpatient vs. outpatient care, whether or not the patient has an overnight stay is what typically defines the difference between the two, but exceptions exist. For example, an emergency room (ER) visit is generally considered an outpatient service, even if a patient will likely require an overnight stay. If an ER visit results in an extended stay and a doctor formally admits the patient to the hospital, that patient’s status changes to inpatient.

Typically, outpatient care can include physical examinations or one-time and ongoing treatments, such as chemotherapy for cancer patients. When surgeons order lab work before performing surgery, patients can visit labs in outpatient centers to save time and costs. The information obtained in the outpatient care visit is then shared with the surgeon, enabling them to determine if underlying health issues may cause complications during a surgical procedure.

Hospitals typically generate more revenue from inpatient services. However, in recent years, a shift toward outpatient care has been growing. The American Hospital Association reports that the revenue gap between outpatient and inpatient services is closing. A large portion of the revenue generated in health care derives from Medicare patients.

According to data from the Kaiser Family Foundation, the total number of Medicare beneficiaries as of 2018 was close to 60 million people. When it comes to inpatient vs. outpatient care, the distinction is critical to ensuring proper payment of health care services for Medicare patients: Medicare Part A pays for inpatient care, while Medicare Part B pays for outpatient care, such as preventive services.

Outpatient care encompasses everything from patients seeking substance abuse treatment in outpatient rehabilitation centers to athletes undergoing surgical procedures for minor injuries. Additional examples include:

• Chest X-rays and CT scans. These can be used to help diagnose causes of chest pain, breathing issues, abnormal heart rhythms, and more.
• Urinalysis: Doctors use this type of test to find causes of kidney pain and bladder infections, and to test for chronic diseases such as diabetes.
• Blood tests: These common tests are used to check for a range of issues, including levels of potassium, sodium, and electrolytes that help regulate body functions.

Outpatient care is administered without an overnight stay in a facility. Outpatient treatments can include routine physical examinations, blood work, urinalysis, CT scans, and chemotherapy sessions.

Various types of facilities provide outpatient care. For example, a doctor’s office can provide annual physicals, preventive care, and pre-surgery blood work. Additional examples of outpatient care facilities include:

• Clinics. Outpatient services in clinics range from wellness, prevention, and weight-loss programs to some surgeries, procedures, and chemotherapy.
• Emergency rooms. A doctor can write an order for a patient to receive outpatient services at a hospital such as observation, surgery, X-rays, and more without having to stay overnight.
• Ambulatory surgery centers. Ambulatory patient services offered in these outpatient facilities offer same-day surgeries for procedures that do not require an overnight hospital stay, such as endoscopies.

The following resources provide further information on outpatient care.

• Johns Hopkins Medicine provides various examples of tests performed in outpatient facilities.
• The American Hospital Association provides information about various long-term and rehabilitation topics.
• Health care practitioners can access various rural outpatient care resources in this online library published by the Rural Health Information Hub.
• The U.S. Department of Health and Human Services (HHS) provides information regarding COVID-19 and outpatient care.

Clinics and hospitals offer different kinds of care. Clinics are much smaller than hospitals and do not offer overnight stays. Clinics are ideal for healthy patients who are undergoing routine preventive care such as immunizations, and those seeking a doctor’s opinion for routine ailments.

Hospitals, on the other hand, offer a wide range of medical specialty services, from outpatient services to inpatient care. Typical examples include cardiology, allergy and immunology, sports medicine, vascular surgery, and urology. In an emergency such as a life-threatening injury or an acute illness, individuals can go to a hospital without an appointment. For nonemergency issues, patients generally must schedule an appointment with a primary care provider, who can then refer them to a specialist if necessary. In addition to emergencies and specialist appointments, patients go to hospitals to receive specific medical treatment or undergo surgery.

According to the American Association of Nurse Practitioners, 14.5% of nurse practitioners (NPs) work in hospital outpatient clinics, while 12.1% work at inpatient hospital units. In both inpatient and outpatient care settings, they help ensure optimal care delivery, but their daily functions may vary.

Nurse practitioners can serve as both primary and specialty care providers. Their responsibilities can extend to include administration, teaching, and research. Specializations in inpatient settings include the following:

• Nurse practitioners (NPs). A nurse practitioner can provide various health care services in a wide range of health care settings, including performing physical exams, ordering diagnostic tests, writing prescriptions, and diagnosing and treating diseases.
• Psychiatric mental health nurse practitioners (PMHNPs). PMHNPs assess, diagnose, and treat mental health needs. Patients can consult PMHNPs for therapy services, psychosocial assessments, and emergency psychiatric care. PMHNPs can develop treatment plans and prescribe medications.
• Adult–gerontology acute care nurse practitioners (AGACNPs). From acute care management to disease prevention, adult–gerontology acute care nurse practitioners provide care for adult and gerontology patients with complex conditions. They often work in intensive care, trauma departments, or critical units within hospitals.
• Women’s health nurse practitioners (WHNPs).: Women’s health nurse practitioners provide health services such as breast cancer screening and diagnosis, pregnancy testing, urinary tract health, prenatal and after pregnancy care, and general health management throughout a patient’s life.

Nurse practitioner specializations in outpatient settings include the following:

• Pediatric nurse practitioners (PNPs). As nurse practitioners focused on treating younger populations, pediatric nurse practitioners perform health examinations, prescribe medications, assess the mental health of children, and manage acute and chronic disease. PNPs typically work with their patients from birth through young adulthood.
• Family nurse practitioners (FNPs). Family nurse practitioners work with people of all ages, managing patients’ health throughout their lives. They provide preventive care, long-term health monitoring, disease management, and more.
• Psychiatric mental health nurse practitioners (PMHNPs). Psychiatric mental health nurse practitioners working in outpatient settings help individuals with cognitive and psychiatric disorders through diagnosis and treatment, including psychotherapy and medicines. They also work in group settings.
• Adult-gerontology primary care nurse practitioners (AGPCNPs). AGPCNPs focus on elderly patients, providing physical and cognitive care, diagnosing diseases, and prescribing medications to manage pain and chronic disorders. They can also order diagnostic tests and provide preventive care and health care education services.

Whether in inpatient or outpatient facilities, nurse practitioners serve a critical role. Medical innovations, the increased digitization of health care, and advancements in care have made it possible for nurse practitioners to take leading roles in patient care. In many states, they can serve as primary caregivers. An advanced degree such as a Doctor of Nursing Practice can help nurses advance their careers and take on leadership roles in various health care settings.