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The ICU jargon decoder

The intensive care unit has a language of its own, and families are expected to learn it on the hardest day of their lives. Type any word you heard at the bedside, or browse by topic, and get the calm, plain-language version.

32 terms, decoded for families.

People and places

ICU / ITU: The intensive care unit (sometimes called the intensive therapy unit). A ward where the sickest patients are watched continuously, usually with one nurse for every one or two patients.
Intensivist: A senior doctor who specialises in intensive care. They lead the team and coordinate all the specialists involved in one patient.
Ward round: The team walk-through, usually every morning, where doctors, nurses and pharmacists review every patient and set the plan for the day. A good time to ask the nurse when updates will be available.
HDU / step-down: The high dependency unit: a level between the ICU and a normal ward. Moving there is usually good news: it means less machine support is needed.

Breathing support

Ventilator: A machine that supports or takes over breathing while the lungs recover. Being "on a ventilator" means the machine is helping; it does not by itself say how the illness will end.; You might hear: "We are keeping her on the ventilator overnight."
Intubated: A soft plastic tube has been placed through the mouth into the windpipe so the ventilator can help with breathing. Patients are kept comfortable with sedation while the tube is in.
Extubation: Removing the breathing tube once the patient can breathe well enough on their own. Often follows a "breathing trial" where the team tests readiness.; You might hear: "If the trial goes well, we will extubate this afternoon."
CPAP / NIV: Breathing support given through a tight-fitting mask instead of a tube: pressurised air that keeps the lungs open. NIV stands for non-invasive ventilation.
Tracheostomy: A small opening in the front of the neck for a breathing tube, used when support is needed for longer. It is usually more comfortable than a mouth tube, needs less sedation, and is often temporary.
Weaning: Gradually reducing the ventilator's help so the patient does more of the breathing themselves. It can take days and often moves two steps forward, one step back: that pattern is normal.

Lines, tubes and drips

Cannula / IV: A thin plastic tube in a vein, usually on the hand or arm, used to give fluids and medicines. Almost every hospital patient has one.
Central line: A longer, more secure drip placed into a large vein, often in the neck or chest. It lets the team give several medicines at once and take blood samples without repeated needles.
Arterial line: A small line in an artery, usually at the wrist, that measures blood pressure continuously and allows painless blood samples.
NG tube: A soft feeding tube passed through the nose into the stomach, used to give liquid food and medicines while a patient cannot eat normally.
Urinary catheter: A tube that drains urine into a bag, standard for very ill patients. It also lets the team measure urine output, an important sign of how the kidneys are doing.

Monitoring and numbers

Sats (SpO2): Short for oxygen saturation: the percentage of the blood's oxygen-carrying capacity currently in use, measured by the glowing clip on a finger. One number in a bigger picture, and the team sets the target range for each patient.; You might hear: "His sats are holding nicely this morning."
Obs / vitals: The routine set of measurements: heart rate, blood pressure, breathing rate, temperature, oxygen. "Doing obs" is the nurse recording them.
Blood gas (ABG): A small blood sample, usually from the wrist or an arterial line, that shows oxygen, carbon dioxide and acidity levels. It helps the team fine-tune breathing support and is often repeated through the day.
GCS: The Glasgow Coma Scale: a standard way of describing how awake and responsive someone is, using eye, voice and movement responses. Sedation lowers it on purpose, so a low number in a sedated patient is expected.
Alarms: Monitors beep whenever any number drifts outside limits the team has set, and most alarms are minor: a sensor moved, a cable bent, a value briefly wandering. Staff triage the sound constantly; silence from the staff usually means the alarm is not worrying them.

Medicines and sedation

Sedation: Medicines that keep a patient calm, comfortable and often lightly asleep, especially while a breathing tube is in place. The depth is adjusted constantly and is reviewed every day.; You might hear: "We are lightening the sedation to see how she responds."
Sedation hold: A planned pause in sedation, often daily, to check how awake the patient can be and whether less sedation is needed. Waking during a hold can look distressing but is closely supervised and genuinely useful.
Vasopressors / inotropes: Continuous medicines that support blood pressure and the heart while the body recovers. Nurses adjust them minute by minute; needing less over time is a common sign of progress.; You might hear: "We have been able to reduce the blood-pressure support today."
Analgesia: The medical word for pain relief. In the ICU it is usually given continuously and adjusted so the patient stays comfortable even if they cannot say so.

Treatments and procedures

Dialysis / CRRT: Machines that do the kidneys' cleaning work when they need a rest. In the ICU it often runs slowly and continuously (CRRT). Kidneys frequently recover after critical illness, so this is support, not necessarily permanent.
Proning: Carefully turning a patient onto their front for several hours so the back of the lungs can work better. It takes a whole team and looks dramatic; it is a routine, well-practised manoeuvre.
Chest physio: Physiotherapy for the lungs and body: clearing secretions, exercising limbs, and later sitting, standing and walking again. Rehabilitation starts far earlier in the ICU than most families expect.

Progress words

"Stable": The numbers are holding steady and nothing is getting rapidly worse. It does not mean "out of danger", but in intensive care steady is genuinely valuable.; You might hear: "She has been stable overnight."
"Critical but stable": Still seriously ill and still needing full support, but not deteriorating right now. The phrase sounds contradictory; it describes a common ICU situation honestly.
"Responding to treatment": The measurements are moving in the right direction since a treatment started: fevers settling, oxygen improving, support reducing. Encouraging, though recovery is rarely a straight line.
ICU delirium: Temporary confusion that is very common during and after critical illness: vivid dreams, muddled days, sometimes fear or suspicion. Distressing to watch, usually not permanent. Familiar voices, glasses, hearing aids, daylight and gentle reorientation all help.
Post-intensive-care syndrome: The mix of physical weakness, memory and concentration problems, and emotional after-effects many survivors (and families) experience for months after the ICU. Recognised, common, and it improves; follow-up support helps.

Reviewed against ICUsteps family guidance and NHS intensive care information.

Sources

Intensive care: a guide for patients and relatives ICUsteps (UK intensive care patient and family charity), 2020
Intensive care NHS, 2023
Life after critical illness Faculty of Intensive Care Medicine (FICM), 2021

Last reviewed: 2026-07-16

Now decode the machines too: what the bedside monitor is really showing, and when you are ready, the family support checklist.