Emergency Room (ER) vs Operating Room (OR)

ER or emergency room receives unexpected patients that require immediate treatment. On the other hand, an operating room or operation theater is where surgeries are performed by medical experts called surgeons.

A hospital’s ER is crowded, while the operating room is large only used when a patient needs surgery. The emergency department of hospitals sometimes receives patients who need surgery and are transferred to OR. Operation theatres ensure a strictly sterile environment. Both departments are closely associated, but there are many differences among them.

Surgical staff

Operation theaters have an exclusive surgical team that performs surgeries. The surgeon performs surgery and makes all the crucial decisions inside OT while the rest of the staff follow orders and help in the procedure. The surgical team includes the following experts that aid the surgeon in surgery:

  • Surgeons
  • Resident doctors
  • Surgical tech
  • Physician assistant
  • Medical equipment expert
  • OR nurse
  • CRNA (certified registered nurse anesthetist)
  • Anesthesiologist

ER staff

ER staff plays a vital role in saving the lives of hundreds and thousands of patients daily. They are well-trained and always ready to tackle health problems. They provide the patients with the best viable treatment in no time. Healthcare staff that is available in this department includes:

  • Emergency physicians
  • Medical officers
  • Registrars
  • Medical students
  • Nurses
  • Pharmacists and physiotherapists
  • General practitioners
  • Staff for x-ray, MRI, CT scan, etc.
  • Administrative staff

The setting of ER and OR

ER and OR serve different purposes, and both play a critical role in a hospital setting. Their setting is quite different from each other. All necessary equipment and supplies should be available for the proper functioning of both departments in a hospital. ER stabilizes and treats emergency patients. It has a pre-hospital setting. In the operating rooms of a hospital, surgeons perform scheduled surgeries as well as emergency operations.

A hospital has a couple of operating rooms because they need ample space and strict germ-free conditions. It constitutes two areas; sterile and non-sterile. Similarly, the personnel is also categorized. The surgeon, his assistant, and the scrub nurse are included sterile OR personnel. Anesthesiologists, medical students, and OR nurses are non-sterile OR personnel. Before entering the restricted or semi-restricted area, the team disinfects themselves. No one can visit, and surgical professionals also show their IDs before entering the operation theatre. They cover shoes, wear scrubs, apply a mask, put on head coverings, and perform surgical hand scrub. Jewellery, artificial nails, and nail paints are forbidden.  Before surgery, all supplies are sterilized. After entering, the team introduces themselves and inquire about the sterile and non-sterile areas. Both personnel are limited to their sites and cannot walk towards the opposite area. A distance of one foot is maintained between the staff of both areas.

If surgery is successful, the patient is kept under observation and transferred to the recovery room.

The emergency room of a hospital is a fast responding, busy spot. They follow few steps to provide emergency care. These steps include; triage, registration, treatment, re-examining, discharging. Triage involves examining the patient to categorize them in any one of five severity levels. Registration is an essential process of gathering data about the patient to provide the best treatment.

The third step is providing the best treatment to the patient by medical staff. Re-examining involves a checkup to determine whether the patient needs to be admitted to the hospital or discharges. The last step is discharging the patient after full recovery. The services are available 24/7. The number of patients treated is never fixed, and it never closes.

Zones in an Emergency Department

The emergency department of a hospital has four zones according to the severity of patients:

  1. Green zone deals with less complex issues like sprains, cuts, or minor head injuries.
  2. Yellow zone treats moderate health issues like pain in the abdomen, minor breathing problems, etc.
  3. Orange zone deals with a bit more complex health issues like dehydration or severe breathing problem.
  4. The Blue/red zone deals with patients experiencing more severe health problems like heart attacks, seizures, cardiac arrests, etc.

Zones in an Operating Room

The zones of Operation Theater are discussed below:

  1. The aseptic zone has operating suits, a scrub station (96 cm height hot and cold water taps and soap and hand scrubbers), an instrument sterilization area, an anesthesia station, and trolleys with trays.
  2. The protective zone includes reception, waiting area, a gallery leading to the entrance, storeroom, pre-anaesthesia room, changing room for staff, a conference hall for meetings, control room, and autoclaves.
  3. The clean zone has a preparatory room, recovery room, frozen section, blood storage room, equipment and medicine room, work room for doctors, nurse room, and anaesthesia room.
  4. The disposal zone has a wash-up area, janitor closet, and a disposal corridor connected to the clean zone.


Surgery costs include surgeon’s fees, hospital fees, other billings for services provided, and medical expert fees other than surgeons involved in the surgery. Surgery fees depend on the type of surgery and vary from hospital to hospital. ER charges also vary and are dependent upon the type of treatment, tests, supplies used, etc. They range from $500 to $2000 (can reach up to $3000 or above). Moreover, overall health care costs are high for patients having no health insurance.

When to visit

ER visits are necessary in case of heart attack, cardiac arrest, automobile and other accidents, heavy bleeding, seizures, allergic reactions, or other injuries that look severe.

Surgeries are needed if the physician prescribes an operation to the patient. They are mostly scheduled. However, sometimes patients received at the ER need immediate surgery such as acute appendicitis. Surgeons perform required (necessary to ensure the patient’s quality of life) emergency and elective surgeries. Elective surgeries are optional, for example, removal of mole or wart. A good example of scheduled or required surgery is the removal of stones from the gall bladder. Emergency surgeries are performed on patients from ER to treat acute illness and trauma.