How Emergency Rooms Work

Medical response
Medics respond to an evening rush-hour accident in Pataskala, Ohio.

Million­s of Americans visit an emergency room each year. Millions more have seen the hit TV show "ER." This­ has sparked an almost insatiable interest in the fascinating, 24-hour-a-day, nonstop world of emergency medicine.

A visit to the emergency room can be a stressful, scary event. Why is it so scary? First of all, there is the fear of not knowing what is wrong with you. There is the fear of having to visit an unfamiliar place filled with people you have never met. Also, you may have to undergo tests that you do not understand at a pace that discourages questions and comprehension.


In this article, Dr. Carl Bianco leads you through a complete behind-the-scenes tour of a typical emergency room. You will learn about the normal flow of traffic in an emergency room, the people involved and the special techniques used to respond to life-or-death situations. If you yourself find the need to visit an emergency room, this article will make it less stressful by revealing what will happen and why things happen the way they do in an emergency department.

Emergency Room Patients

Medical personnel place an injured person into an ambulance
Medical personnel place an injured person into an ambulance outside the Pentagon, Arlington, Virginia, Sept. 11, 2001.
Photo courtesy U.S. Navy, photo by Journalist 1st Class Mark D. Faram

One of the most amazing aspects of emergency medicine is the huge range of conditions that arrive on a daily basis. No other speciality in medicine sees the variety of conditions that an emergency room physician sees in a typical week. Some of the conditions that bring people to the emergency room include:

  • Car accidents
  • Sports injuries
  • Broken bones and cuts from accidents and falls
  • Burns
  • Uncontrolled bleeding
  • Heart attacks, chest pain
  • Difficulty breathing, asthma attacks, pneumonia
  • Strokes, loss of function and/or numbness in arms or legs
  • Loss of vision, hearing
  • Unconsciousness
  • Confusion, altered level of consciousness, fainting
  • Suicidal or homicidal thoughts
  • Overdoses
  • Severe abdominal pain, persistent vomiting
  • Food poisoning
  • Blood when vomiting, coughing, urinating, or in bowel movements
  • Severe allergic reactions from insect bites, foods or medications
  • Complications from diseases, high fevers


Understanding the ER Maze

The classic emergency room scene involves an ambulance screeching to a halt, a gurney hurtling through the hallway and five people frantically working to save a person's life with only seconds to spare. This does happen and is not uncommon, but the majority of cases seen in a typical emergency department aren't quite this dramatic. Let's look at a typical case to see how the normal flow of an emergency room works.

Imagine that it's 2 a.m., and you're dreaming about whatever it is that you dream about. Suddenly you wake up because your abdomen hurts -- a lot. This seems like something out of the ordinary, so you call your regular doctor. He tells you to go to your local hospital's emergency department: He is concerned about appendicitis because your pain is located in the right, lower abdomen.



When you arrive at the Emergency Department, your first stop is triage. This is the place where each patient's condition is prioritized, typically by a nurse, into three general categories. The categories are:

  • Immediately life threatening
  • Urgent, but not immediately life threatening
  • Less urgent

This categorization is necessary so that someone with a life-threatening condition is not kept waiting because they arrive a few minutes later than someone with a more routine problem. The triage nurse records your vital signs (temperature, pulse, respiratory rate and blood pressure). She also gets a brief history of your current medical complaints, past medical problems, medications and allergies so that she can determine the appropriate triage category. Here you find out that your temperature is 101 degrees F.

What's next? You need to register.



After triage, the next stop is registration - not very exciting and rarely seen on TV. Here they obtain your vital statistics. You may also provide them with your insurance information, Medicare, Medicaid or HMO card. This step is necessary to develop a medical record so that your medical history, lab tests, X-rays, etc., will all be located on one chart that can be referenced at any time. The bill will also be generated from this information.

If the patient's condition is life-threatening or if the patient arrives by ambulance, this step may be completed later at the bedside.


Examination Room

Now you are brought to the exam room. You promptly throw up in the bathroom, which may be more evidence of appendicitis. You are seen by an emergency-department nurse who obtains more detailed information about you. The nurse gets you settled into a patient gown so that you can be examined properly and perhaps obtains a urine specimen at this time.

Some emergency departments have been subdivided into separate areas to better serve their patients. These separate areas can include a pediatric ER, a chest-pain ER, a fast track (for minor injuries and illnesses), trauma center (usually for severely injured patients) and an observation unit (for patients who do not require hospital admission but do require prolonged treatment or many diagnostic tests).

Once the nurse has finished her tasks, the next visitor is an emergency-medicine physician. He gets a more detailed medical history about your present illness, past medical problems, family history, social history, and a complete review of all your body systems. He then formulates a list of possible causes of your symptoms. This list is called a differential diagnosis. The most likely diagnosis is then determined by the patient's symptoms and physical examination. If this is inadequate to determine the diagnosis, then diagnostic tests are required.


Diagnostic Tests

Tubes used in blood tests
Tubes used in blood tests

When the tricky diagnosis of appendicitis is considered, blood tests and a urinalysis are required. The patient's blood is put into different colored tubes, each with its own additive depending on the test being performed:

  • A purple-top tube is used for a complete blood count (CBC). A CBC measures: 1) The adequacy of your red blood cells, to see if you are anemic. 2) The number and type of white blood cells (WBCs), to determine the presence of infection. 3) A platelet count (platelets are a blood component necessary for clotting)
  • A red-top tube is used to test the serum (the liquid or non-cellular half of your blood).
  • A blue-top tube is used to test your blood's clotting.

The tests in your case indicate that you have an elevated WBC count. This is a sign of a bacterial infection, and bacterial infections are commonly associated with appendicitis.


At this point, the emergency physician may request that you not eat or drink anything. The reason is that appendicitis is treated by surgery, and an empty stomach is desirable to prevent some complications of anesthesia.

Diagnosis and Treatment

When the emergency physician has all the information he can obtain, he makes a determination of the most likely diagnosis from his differential diagnosis.

Alternately, he may decide that he does not have enough information to make a decision and may require more tests. At this point, he speaks to a general surgeon -- the appropriate consultant in this case. The surgeon comes to see you and performs a thorough history, physical exam, and review of your lab data. She examines your symptoms: pain and tenderness in the right, lower abdomen, vomiting, low-grade fever and elevated WBC count. These symptoms all point to appendicitis. The treatment of appendicitis is removal of the appendix, or an appendectomy. The surgeon explains the procedure, including the risks and benefits. You then sign a consent form to document this and permit her to operate on you.

Who's On First

The vast array of people caring for patients in an emergency department can be quite confusing to the average health care consumer -- as confusing as if you were watching your first baseball game ever and no one was around to explain all those players.

Additionally, most people are uncertain of the training and background necessary to become a member of the emergency-department team. Well, here's the scorecard.


Emergency Physician

The emergency physician comes to the team after spending four years in college studying hard to get as high a GPA (grade point average) as possible in order to get accepted into medical school.

Medical school is a four-year course of study covering all the essentials of becoming a physician. It generally includes two years of classroom time, followed by two years rotating through all the different specialties of medicine.

Toward the end of medical school, each medical student must select a particular specialty (emergency medicine, family practice, internal medicine, surgery, pediatrics, etc.). The medical student then completes an internship (one year) and residency (two to three additional years) in order to be a specialist in emergency medicine.

Physicians must pass an all-day written exam and an all-day oral exam to become board certified in emergency medicine. As of 2001, there were approximately 32,000 emergency physicians practicing in the United States, of which 17,000 were certified by the American Board of Emergency Medicine.

Emergency Nurse

The emergency nurse comes to the team in a number of ways. One way is completing a four-year degree in college to obtain a BSN. (bachelor of science in nursing). Alternately, a nurse may complete a three-year diploma program (usually at a hospital) or a two-year associates degree program (usually at a community college). After completing any of these academic endeavors, the nursing graduate is eligible to take a licensing exam. After passing this exam, the nursing graduate becomes an RN (registered nurse) and can practice nursing. Many emergency nurses take an additional exam to become a CEN (Certified Emergency Nurse).

Physician Assistant

Many emergency departments utilize physician assistants (PA). PAs work under the supervision of an emergency physician. They can examine, diagnose and treat patients (usually the less complicated ones) and review their findings with the physician. In most states, they can prescribe medications. Typically, a PA has at least two years of college (most have a four-year degree) and some health-care experience before completing a two-year program to become a physician assistant. An exam is required to become licensed.

Emergency Department Technician

Many emergency departments have emergency technicians who perform a variety of tasks depending on the institution and state laws. Some of these tasks may include taking your vital signs, drawing your blood, starting your IV, performing EKGs, transporting you to and from various tests, and providing aid and comfort to family and friends. Training varies widely, but these technicians are often ambulance personnel or else are trained through the hospital.

Unit Secretary

This essential member of the team is one you don't hear about very often. He/she often handles the communication needs of the ER. A few important examples of important communication needs include the emergency physician needing to speak to the patient's family physician, families calling about their loved ones, family physicians needing to inform the emergency department about patients being sent in, or patients calling in needing medical advice. Also, he/she coordinates the ordering of diagnostic tests.

Physicians in Training

At teaching hospitals, you may be examined by an intern or resident. Teaching hospitals are hospitals that have training programs for physicians and are usually affiliated with a medical school. Interns are in their first year of training after graduating medical school. After the first year, the physician in training is called a resident. These physicians are supervised by an attending physician who usually has extensive experience in emergency medicine.


Tools of the Trade

Photo courtesy Morgue File

Emergency Departments are stocked with a huge array of strangely named, oddly shaped, beeping and blinking equipment. Here's a quick look at a typical lineup.


A stethoscope doesn't beep or blink, but it is an incredibly useful diagnostic tool. A stethoscope lets a nurse or physician listen to heart and respiratory sounds. One heart sound that can be easily heard with a stethoscope is a heart murmur. The presence of a murmur can be a sign of an abnormal heart valve. Heart sounds are also used to help the physician decide on the rhythm of the heart. If a friction rub is heard, this can be a sign of pericarditis (inflammation around the heart.) Extra heart sounds can be a sign of heart failure.


A stethoscope is also used to listen to the lungs. A physician can diagnose various diseases such as pneumonia, asthma, pneumothorax (collapsed lung), or congestive heart failure this way.

A stethoscope is used to take your blood pressure (BP) by listening to the flow of blood through your arteries. A BP is obtained when a BP cuff is wrapped around your arm and inflated to a pressure high enough to stop the flow of blood in the artery in your arm. The stethoscope is then placed over the artery. Air is slowly let out of the cuff. Blood flow starts when the pressure in the cuff becomes lower than the pressure in the artery. This creates a sound that can be heard with a stethoscope. The pressure on the BP gauge is the upper number in a BP reading. The lower number is the pressure at which the artery is no longer compressed and the sound stops. A normal BP is less than 140 for the upper number (systolic BP) and less than 90 for the lower number (diastolic BP).

Cardiac Monitor

Cardiac monitor
Cardiac monitor

A cardiac monitor gives a visual display of the rhythm of your heart. This is very useful information, particularly during a heart attack when you can suddenly develop a lethal cardiac rhythm. You are connected to the monitor by three sticky patches on your chest, attached to the monitor via wires. Cardiac monitors are set to alarm if your heart rate goes above or below a predetermined number. Some monitors also have an automatic blood pressure cuff and a pulse oximeter (which measures the oxygen saturation of your blood).

Suture tray
Suture tray

Suture Tray

This tray contains the sterile equipment needed to place sutures (stitches) in a patient with a laceration. These include: needle holder (the instrument that holds the needle containing the suture material), forceps (used to hold the lacerated tissue), sterile towels (used to drape off the non sterile areas which are not being repaired), scissors, and small bowls (to hold antiseptic solutions).

Orthopedic Equipment

Most emergency departments have a generous number of orthopedic devices for many purposes. These include plaster and/or fiberglass materials to splint extremities that are fractured or severely injured. You'll also find pre-made splints for specific joints, such as knee immobilizers, aluminum finger splints, Velcro wrist splints, shoulder slings, air splints (for ankles), and cervical collars, as well as cast cutters to use when a cast has become too tight.

Now, let's take a look at a crash cart.

Crash Cart

Select contents of an ER crash cart you might find by a patient's bedside.
Select contents of an ER crash cart you might find by a patient's bedside.

A crash cart is a cabinet containing equipment that physicians and nurses need when a cardiac arrest occurs (the heart stops beating). This is obviously a grave situation and requires immediate life-saving steps. These are some of the items found on a crash cart:

  • Defibrillator - This is an electrical device with two paddles that are placed on your chest. It discharges electricity through your heart when a lethal rhythm is present. The goal is to shock the heart back to normal. "Lethal rhythms" include ventricular fibrillation (rapid, unsynchronized, uncoordinated heartbeat) and ventricular tachycardia (rapid heartbeat that prevents the heart from pumping properly). It can also be used in less dangerous rhythms to return the heart to a normal rhythm.
Tools used in endotracheal intubation
Tools used in endotracheal intubation
  • Endotracheal intubation equipment - Endotracheal intubation is the procedure of placing a tube into someone's trachea (windpipe) when that person stops breathing or is not breathing adequately. The tube allows artificial respiration equipment to take over the job of breathing for the patient. The package includes tubes of different sizes and a laryngoscope -- a special light with a flat metal piece to lift the tongue out of the way so that a tube can be placed into the trachea.
  • Central vein catheters - These are catheters (small tubes) placed in the large central veins (near the heart) so that medications and fluids can reach the heart and important organs quickly.  
  • Cardiac drugs - During a cardiac arrest, certain potent drugs are required to restart the heart or return it to a more stable rhythm.

The most common lethal arrhythmias present during a cardiac arrest are:


  • Ventricular fibrillation - Twitching of the ventricle (main chamber of the heart), as opposed to an effective contraction that pumps blood out of the heart
  • Ventricular Tachycardia - Rapid contraction of the ventricle, producing insufficient blood flow out of the heart
  • Asystole - Total absence of electrical activity and therefore no contraction of the heart
  • Pulseless electrical activity (PEA) - Electrical activity of the heart but inadequate contraction of the heart
  • Bradycardia - Various rhythms that cause the heart to beat so slowly that not enough blood is pumped out of the heart

Some of the drugs that are used to treat these arrhythmias are:

  • Epinephrine - Used in ventricular fibrillation, pulseless ventricular tachycardia, asystole, PEA, and sometimes bradycardia
  • Atropine - Used in asystole, bradycardia and sometimes PEA
  • Lidocaine - Used in ventricular fibrillation and ventricular tachycardia

There are many other pieces of equipment that are used in an emergency department, including the chest-tube tray, which holds the equipment needed to put in a chest tube (a tube placed between the ribs and the lung to re-expand a collapsed lung), and an ear, nose and throat tray, which holds specialized equipment used most commonly for nosebleeds and to remove foreign bodies from the ear, nose, or throat.


Depending on a patient's specific medical condition, physicians will either admit the patient to the hospital, discharge the patient, or transfer the patient to a more appropriate medical facility.

If you are discharged, you will receive discharge instructions (either written specifically for you or pre-printed) that explain your medications and other treatments. If medications are prescribed, you may receive a beginning dose if there are no pharmacies open in your area at that particular time. You will also be referred for follow-up care should your condition continue or worsen.


You may need to be transferred if your condition is better treated at another institution. You may have to sign a consent form if your condition or mental state allows.

The modern emergency department performs an important role in our society. It really is a marvelous invention that has saved countless lives. Hopefully, the information in this article will help ease your fears should you need the services of an emergency department in the future.

For more information on emergency departments, medical conditions and related topics, check out the links on the next page.


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About the Author

Dr. Carl Bianco, M.D. is an emergency physician practicing at Dorchester General Hospital in Cambridge, MD, located on the Eastern Shore of Maryland. Bianco attended medical school at Georgetown University School of Medicine, and he received his undergraduate degree from Georgetown University majoring in nursing and pre-med. He completed an internship and residency in Emergency Medicine at Akron City Hospital in Akron, Ohio.

Dr. Bianco lives near Baltimore with his wife and two children.