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ICU Glossary

This is a glossary of terms used in the ICU.

ICU conditions

Respiratory failure

Typically caused by a condition that makes it harder for the lungs to take in oxygen or remove carbon dioxide. To manage this issue, the ICU team treats the cause of respiratory failure and provides different types of therapies to make it easier for the lungs to take up oxygen and exhale carbon dioxide.



Depressed mental status or confusion. Often, there are multiple reasons patients have encephalopathy such as inflammation in the body, low blood pressures, sedating medications, and electrolyte imbalances.


Sepsis/septic shock

Sepsis occurs when the body's response to an infection causes inflammation throughout the body. It can lead to low blood pressure (septic shock) and organs to not function normally.


Renal failure

Renal (kidney) failure is common among ICU patients. It is often related to medical issues that cause low blood pressure. Renal failure can lead to confusion, fluid and acid build up, and electrolyte imbalance which can be life threatening. This issue requires close monitoring of blood work and urine production. Sometimes, dialysis is needed.



Central line

A thin, flexible tube (catheter) that is placed in a large vein in the neck or groin. It is used to provide medication and monitor the patient.


Arterial line

A thin, flexible tube (catheter) that is placed in an artery in the wrist or groin to closely monitor blood pressure and levels of oxygen and carbon dioxide in the blood


Dialysis line

A thin, flexible tube (catheter) that is placed in a large vein in either the neck or groin to provide dialysis.


Peripherally inserted central catheter (PICC)

A thin, flexible tube (catheter) that is inserted into a vein in the arm and threaded through to the larger veins near the heart.


Endotracheal tube/intubation

Intubation is the procedure where an endotracheal tube is inserted through the mouth to the main airway of the lungs (trachea). One end of the endotracheal tube is connected to the mechanical ventilator (breathing machine)


Spontaneous Awakening Trials (SAT)

The sedating medications are temporarily stopped and the patient's level of alertness is assessed. It is usually done around the same time as a Spontaneous Breathing Trial (SBT)


Spontaneous Breathing Trial (SBT)

Adjusting the settings on the ventilator to simulate normal breathing. Passing this test helps makes the decision to remove the breathing tube.


Tracheostomy tube

A surgical procedure in which a small tube is inserted through the neck to the main airway of the lungs (trachea). A tracheostomy tube is more comfortable and safer over the long term than an endotracheal tube. It allows patients to wean from the ventilator (breathing machine)


Nasogastric (dobhoff) or orogastric tube

A tube that goes through the nose (nasogastric) or mouth (orogastric) to the stomach to provide nutrition and medication


Percutaneous gastrostomy tube (PEG)

A tube that goes through the skin to the stomach to provide long-term nutrition and medication


Chest tube

A tube that goes in between the ribs to drain fluid or air that has accumulated around the lung. The tube is secured to the skin after insertion and usually connected to a suction device.



A procedure where fluid that has accumulated around the lung is drained. The fluid can be sent to the lab for testing. Removal of fluid can provide relief of symptoms.



A procedure where fluid that has accumulated in the abdomen is drained. The fluid can be sent to the lab for testing. Removal of fluid can provide relief of symptoms.


Electroencephalogram (EEG)

Sensors are attached to the scalp to measure brain waves, typically to determine whether the patient is having seizures


Lumbar puncture or spinal tap

A procedure where a small amount of fluid that surrounds the spinal cord is removed and sent to the lab for analysis


Supportive care

Mechanical ventilation

A medical treatment that involves the use of a machine to assist or replace normal breathing. The ventilator or breathing machine, pumps air or oxygen into the lungs of a patient who is unable to breathe on their own. A ventilator can be life-saving but it does not fix the reason for the breathing problem. It helps support the patient’s breathing while the primary reason for initiating the ventilation improves. The medical team tries to take patients off the ventilator at the earliest possible time.


Non-invasive (BiPAP) vs. invasive mechanical ventilation

The ventilator is connected to a face mask (non-invasive) or endotracheal tube (invasive).  With non-invasive ventilation, patients are awake and initiating breaths on their own. Non-invasive ventilation is preferable for some conditions. Some patients require invasive ventilation if they do not tolerate non-invasive ventilation or a greater level of support is needed.


High flow oxygen

Extra oxygen delivered to the lung though cannula (tubes) in the nose or face mask.



Patients receiving mechanical ventilation typically require at least one sedating (sleepy) medication to be given as a continuous infusion through their IV. Nurses usually adjust how much sedating medication is being given so that patients are comfortable but still arousable. For some patients, it is safest for them to be deeply sedated (unarousable)



Medications that cause the blood vessels to tighten, increasing blood pressure. Vasopressors are usually provided continuously through a central line. The amount of vasopressor support a patient requires is often an indication of how sick he or she is.



A medical treatment that is used to remove excess waste and fluid from the blood of patients whose kidneys are not working properly. Dialysis does not fix the kidneys.  For some patients, the need for dialysis is temporary; some patients continue to need dialysis after the ICU stay.


Artificial Nutrition

Nutrition provided to the gut (enteral) or blood (parenteral) for patients who are not awake enough to eat on their own or swallow independently.


Foley catheter

A tube placed through the urethra to the bladder to drain urine.


Barriers to recovery

Dependence on a mechanical ventilator (chronic respiratory failure)

Some patients are unable to come off a ventilator (breathing machine) in an ICU. It could be that the patient’s lungs are healing slowly or new problems developed during the ICU stay. The team adjusts the ventilator settings each day to help them wean off the ventilator.



A type of confusion that often occurs in ICU patients. Patients with ICU delirium may have difficulty focusing, following commands, or remembering things. ICU delirium is thought to be related to a combination of factors such as sleep deprivation, pain, stress, immobility, and exposure to certain medications.


ICU-acquired weakness

Muscle weakness and wasting, which can occur in both the upper and lower extremities, as well as in the diaphragm and other respiratory muscles. It thought to be related to a combination of factors such as immobility, inflammation, exposure to certain medications, and mechanical ventilation.


Skin failure/breakdown

A complication of prolonged critical illness and is due to a combination of factors including pressure on the skin and increased fragility from malnutrition and swelling


Distressing symptoms

Symptoms such as pain, shortness of breath, anxiety, depression, and sleep disturbance are common among ICU patients. Distressing symptoms sometimes prevent patients from making progress with physical and occupational therapy. The team will often try to find combinations of medications that treat symptoms without making the patient too sedated (sleepy).



ICU patients often have increased nutritional needs due to their medical condition. They may have difficulty meeting these needs due to a variety of factors such as poor appetite, difficulty swallowing, and malabsorption. Malnutrition can lead to muscle wasting, weakness, and decreased immunity, which can prolong the recovery time.


Hospital-acquired infections

ICU patients are at risk for new infection for many reasons including weakened immune systems, skin breakdown, malnutrition, and weakness.


Post-intensive care syndrome (PICS)

A set of physical, cognitive, and mental health problems that can occur in patients after they have been discharged from an ICU. These problems can include physical weakness, difficulty with memory and concentration, depression, anxiety, and post-traumatic stress disorder (PTSD).


Discharge planning

Goals of care meeting

The ICU team will periodically schedule meetings with the patient and family to discuss the patient's condition and any barriers to recovery. The purpose is to establish the goals that are trying to be achieved (i.e., getting home) and the types of therapies that may be required to attempt to achieve these goals.


Code status

Instructions to the ICU team for what to do in the event that the patient's heart stops or needs to go on a ventilator emergently. "Full code" means that the medical team will perform cardiopulmonary resuscitation or CPR if the patient's heart stops. "Do Not Attempt Resuscitation or DNR" means that the team will not attempt CPR if the patient's heart stops


End of life care

Patients sometimes receive end of life care in the ICU. The focus is on treating distressing symptoms and allowing family to be present with the patient.


Rehabilitation hospital

Rehabilitation hospitals offer a wide range of services, including physical therapy, occupational therapy, and speech therapy, as well as nursing care and medical management. The goal of treatment in a rehabilitation hospital is to help patients regain as much function and independence as possible, so they can return to their normal activities.


Long-term acute care hospital (LTACH)

LTACHs are rehabilitation hospitals that provide care for critically ill patients who have a prolonged recovery process and require complex medical care. They may also provide specialized services such as ventilator management and management of tracheostomies. Patients may receive care from a team of healthcare professionals including physicians, nurses, respiratory therapists, physical therapists, and occupational therapists.