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Dr. Steven Mickley Community Health Resource Section of the Greenwich Hospital Medical Library: Medical and Surgical Intensive Care Unit (MSICU)

Community Health Resource Section servicing Greenwich Hospital patients, their families/caregivers, and the community at large.

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  • American Thoracic Society (ATS)
    The ATS Patient Information Series now includes more than 70 fact sheets on topics ranging from pulmonary function testing in children, bronchoscopy and arterial catheterization to sleep studies, smoking cessation, and pulmonary rehabilitation.
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    National Heart, Lung, and Blood Institute
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MSICU Glossary of Terms
(from the Society of Critical Care Medicine)

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  • Acute respiratory distress syndrome (ARDS): A health problem that occurs when the lungs are not able to give the blood enough oxygen. Patients who have ARDS are very ill and need medical treatment. They usually end up in the intensive care unit (ICU) on a machine that helps them breathe (ventilator).
    ARDS is caused by liquid that gets into the lungs, which should never have liquid in them. The goal of treating ARDS is to support the patient in the ICU until his or her lungs heal.
  • Advance directive: Instructions from a patient (spoken or written) about treatments the patient would want or not want and about who should make medical decisions if the patient cannot do this personally. Advance directives include living will, durable power of attorney for health care, and health care proxy.
  • Arterial blood gas (ABG, blood gas, gas): Blood test on a sample of blood from the artery that helps the doctors and nurses know how well a patient is breathing by measuring the amounts of oxygen and carbon dioxide.
  • Arterial line (a-line, art line): A small tube in the artery, usually placed in the wrist. The care team use this tube to check the patient's blood pressure and take blood samples.
    Some patients in the ICU need drugs that can harm their body over time. If so, they need their blood checked regularly. Having an a-line is more comfortable for them than getting stuck with a needle each time.
  • Attending physician: Senior doctor on the health care team who oversees the patient’s care.

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  • Blood pressure: A force that pushes against the walls of an artery as blood moves through the artery. Having high blood pressure for a long time is dangerous. It stiffens arteries and makes them vulnerable to fat buildup, which can lead to a heart attack, a stroke or kidney failure.
  • Brain death: One of two kinds of death known by law—the first and most common kind occurs when the heart stops. Brain death occurs when the brain stops working. The heart of the patient who is brain dead may continue to beat, but the patient cannot breathe without machines. He or she cannot have any thoughts or feelings, including pain. When this happens, life support is turned off.
    Turned-off support is not the same as withdrawn support. Support is withdrawn when the patient is alive but has chosen to die comfortably over time.

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  • Cardiac arrest: The sudden loss of all heart function. Cardiac arrest is not the same as a heart attack, which occurs when blockage causes sudden damage to the heart. A heart attack may lead to cardiac arrest, but cardiac arrest is usually caused by: Cardiac arrest permanently damages the brain within four to six minutes of occurring. Ninety-five percent of people who experience it do not survive. Those who do survive are likely to need critical care.
  • Cardiac monitor (heart monitor, monitor): Screen that shows the patient’s vital signs (heart rate, blood pressure, oxygen levels, breathing rate). Various wires and cables connect the patient to this monitor.
  • Catheter (tube, line, drain): Plastic tube placed in a blood vessel (vein or artery) or another part of the body (eg, bladder catheter to drain urine).
  • Central line (central venous catheter, CVC, IJ, subclavian line, femoral line): Special intravenous catheter in a large vein (usually near the neck or collar bone) to give fluids, medications, or nutrition or to measure blood pressures in and around the heart.
  • Chest tube: A large tube inserted through the skin into the lungs. The chest tube removes air or blood that makes breathing hard to do for the patient.
  • COPD (chronic obstructive pulmonary disease): An illness that makes breathing hard to do. The lungs are too stiff or too floppy. Patients with COPD cough often, producing too much mucus. They may wheeze or feel tightness in their chest. Common COPDs include bronchitis and emphysema. Asthma is also a COPD. It has no cure, but the care team can treat it with medicine.
  • Coronary heart disease: Coronary heart disease (CHD) is a disease in which a waxy substance called plaque builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart muscle.
  • CPR (cardiopulmonary resuscitation): A procedure to try to restart the heartbeat if a patient has a cardiac arrest—that is, if the patient’s heart and breathing stop. This procedure combines pressing on the chest and giving rescue breathing (in the ICU, this is done by machine) and administering medications.
  • Critical care nurse: A highly skilled nurse who provides all aspects of care for a very ill patient. This nurse helps all of the people involved in that care talk to one another. He or she has close contact with the patient and family and can often uphold the patient's wishes. The critical care nurse becomes an important part of decision-making with the patient, the family, and the care team.
    A registered nurse (RN) who is certified in critical care is known as a CCRN. CCRNs are certified by the American Association of Critical-Care Nurses.
  • Critical care team (ICU team): Team of health care professionals who care for critically ill patients and their families; this team includes the attending intensive care doctor critical care nurserespiratory therapist, registered dietitian, physical therapist and pharmacist. Social workers, clergy, and others may also be members of the critical care team. Some ICUs have nurse practitioners or physician assistants.

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  • Dialysis: Removing waste from the blood with special medical equipment. Dialysis helps the patient whose kidneys have failed.
  • Do-not-resuscitate (DNR, do-not-attempt resuscitation, DNAR): A directive (order) that instructs doctors and nurses not to attempt to restart the patient’s heartbeat or breathing through CPR.
  • Durable power of attorney for health care: Legal document that gives another person— called a “surrogate decision-maker”—the authority to make health care decisions for a patient when the patient is unable to do so personally.

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  • ECG (EKG): Equipment that monitors and shows the heartbeat.
  • End-of-life care: The medical care that a very ill patient receives when he or she will not regain health. Many ICUs have rules in place for this care. The goal of end-of-life care is to make sure the patient dies as dignified and pain-free as possible. End-of-life care can take place in the hospital, a home or the hospice unit.
  • Endotracheal tube (ET tube, ETT): Breathing tube that is placed in the patient’s airway (trachea) through the mouth or nose (or through the neck after a tracheotomy). This tube is attached to a mechanical ventilator (breathing machine) to help the patient breathe.

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  • Face mask (oxygen mask, O2 mask): Plastic mask that is placed over the nose and mouth. The mask is attached to a plastic hose that gives oxygen (from a tank or wall source) to help the patient breathe.
  • Fellow (ICU fellow): Doctor who is training to care for critically ill patients and their families.

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  • Health care proxy (proxy): Similar to durable power of attorney for health care; see above.


  • Intensivist (intensive care doctor): Doctor or nurse with special training to care for critically ill patients and their families.



  • Myocardial infarction (heart attack): A health problem that occurs when the heart suddenly stops receiving oxygen-rich blood from the arteries.

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  • Nasal cannula (cannula): Plastic tube that fits around the head with two short prongs into the nostrils. It provides the patient with oxygen (from a tank or wall source).
  • Nasogastric tube (NGT, NG), orogastric tube (OGT, OG): A tube placed through the nose or mouth into the stomach. It is used to give medicines and feedings or to drain stomach contents.

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  • Pacemaker: A machine with an electrical current that stimulates the heart so it beats at a normal pace. The pacemaker can be placed under the skin for a short amount of time or for the rest of the patient's life.
  • Palliative care: Medical care for the patient who is very ill and has pain that impairs his or her daily life. Medical treatment does not always stop the pain but can ease it. The easing of pain is palliative care. Palliative care can also prepare the patient and family in coping with an illness. End-of-life care is a form of palliative care, but they are not the same thing. The patient can receive palliative care at any time during his or her illness. End-of-life care, on the other hand, is comfort for the dying patient.
  • PEG (percutaneous endoscopic gastrostomy): Tube placed through the skin and wall of the abdomen into the stomach to give feedings (and medicines) to patients who cannot take these by mouth.
  • Persistent vegetative state: A health problem that occurs after the patient "wakes" from a coma. After waking, the patient regains low levels of consciousness but is not aware of his or her surroundings. The patient can open his or her eyes, make a face, or make a noise, but these are all automatic functions of the body. The patient cannot "think" or speak. He or she cannot reason with or relate to the surroundings.
  • Pharmacist: An expert in drugs who works with the care team to prescribe drugs the patient needs. The pharmacist checks the progress of these drugs during the patient's stay in the hospital.
  • Physical therapist: A caregiver who helps restore a function of the body that involves the muscles, bones, tissues or nerves. With this help, the patient can better move around in daily life (for example, walking, going up and down the stairs). The physical therapist uses techniques such as stretching and heat. These techniques can reduce pain and swelling. They can also prevent permanent physical disability.
  • Pneumonia: Pneumonia is a bacterial, viral, or fungal infection of one or both sides of the lungs that causes the air sacs, or alveoli, of the lungs to fill up with fluid or pus. Symptoms can be mild or severe and may include a cough with phlegm (a slimy substance), fever, chills, and trouble breathing.
  • Pulse oximeter (pulse ox, O2 sat monitor): Device placed on finger, toe, or earlobe to check how much oxygen is in the blood.

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  • Registered dietitian: A caregiver trained and licensed in nutrition and illness. The registered dietitian works with the care team and the family to improve the health of the patient who lacks nutrients. The registered dietitian can lead or perform feedings by mouth, tube or vein.
  • Renal failure (kidney failure): A health problem that occurs when the kidneys stop working in the way they should. Kidneys remove extra water and poisons from the body. If they fail and are not medically treated, water buildup can cause skin swelling in the arms, legs and face. It can also cause problems with breathing or in other organs. Poisons can affect the brain, and the patient may get sleepy or go into a coma.
  • Respiratory failure: A health problem that occurs when the lungs do not work in the way they should. Respiratory failure can occur in the ICU or be the reason someone is in the ICU. It is caused by health problems that affect breathing, such as: To treat respiratory failure, the care team can strengthen or support the patient's breathing. They can bring up mucus from the patient's lungs or put the patient on a breathing machine.
  • Respiratory therapist: A caregiver who has special knowledge and practice in healing problems with breathing. The respiratory therapist uses lung treatments to help the patient breathe.

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  • Sedative: A drug that calms down the patient when he or she is injured or during a medical procedure. The patient who is on a sedative may appear less alert or asleep.
  • Sepsis: A serious infection in the body that causes the heart, blood vessels, and cells to work in ways other than they should. The patient's response to an infection can cause the body to inflame and the infection to get out of control. Many organs are affected, so the patient becomes very ill.
  • Shock: State of the body when the organs do not get enough oxygen and then blood pressure drops. Some causes of shock include:
    • Lack of fluids
    • Severe blood loss
    • Heart attack
    • Sepsis
    • Any massive trauma to the body, such as a car crash
    If the care team is not able to reverse shock quickly, the patient's organs start to shut down. Symptoms of shock include:
    • Confusion
    • Cool and clammy skin
    • Bluish lips
    • Dizziness
    • Sweating
    • Heavy breathing
  • Stroke: A health problem that occurs when the brain stops getting oxygen-rich blood from the artery. An ischemic stroke is caused by a blood clot, and a hemorrhagic stroke is caused by bleeding into the brain. Ischemic strokes are more common than hemorrhagic strokes.
    Strokes that occur on one side of the body affect how the other side of the body works. Strokes that occur in the right part of the brain often cause vision problems and memory loss. Strokes that occur in the left part of the brain often cause speech or language problems and memory loss.
  • Suction: Removal of secretions (phlegm or mucus) or drainage from the patient’s airway (trachea) or other part of the body (e.g. stomach).
  • Surrogate decision-maker: Someone who makes medical decisions on the patient's behalf. The surrogate is usually a family member or close friend. The surrogate must be trustworthy, responsible and ready. He or she must know the patient's personal values and consider the pros and cons of each treatment.
    If the patient has not chosen a surrogate before becoming ill, the attending physician (doctor) helps the family pick one. The choice is based on hospital or local laws.

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  • Tracheotomy (tracheostomy, trach): Surgical opening in the neck for a breathing (endotracheal) tube into the patient’s airway (trachea). This tube is attached to a mechanical ventilator (breathing machine) or an oxygen mask to help the patient breathe.
  • Tube feeding: Giving food in the form of liquid through a tube. The tube goes from the nose to the stomach. It can also go through the skin directly into the stomach or intestines. Patients need tube feedings when they are not able to eat or lack nutrients. A tube feeding is safer and less expensive than an intravenous feeding, but it requires the patient to have a working stomach and intestines.

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  • Vasoactive drugs (vasopressors, pressors, drips): Medicines that are given by vein (intravenously) to raise or lower blood pressure and boost the heartbeat.
  • Ventilator/respirator (vent, breathing machine, mechanical ventilator): Machine attached to the patient by a tube (in mouth, nose, or neck) to help the patient breathe.


  • Weaning: Process of trying to help the patient become free of the breathing machine by lessening the help from the machine step by step.

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What is coronary heart disease? (2016, June 22). Retrieved from National Heart, Lung, and Blood Institute website:

Feldman, J. D. (2010). Chronic critical illness. Retrieved from Society of Critical Care Medicine website:

Glossary. (n.d.). Accessed August 30, 2017, from Society of Critical Care Medicine website:

Pneumonia. (2016, September 26). Retrieved from National Heart, Lung, and Blood Institute website:

**Please note: Information found on these websites is for educational purposes only. Always ask your doctor for any medical advice.**

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