Spontaneous Awakening & Breathing Trials

Part of the ICU Emergencies Hub — browse every related guide in one place.

Updated July 2026  |  More ICU nursing guides →

Every day a patient stays sedated and ventilated is a day of accumulating risk — delirium, muscle wasting, ventilator-associated pneumonia, and longer stays. The most powerful tool the ICU has for reversing that is embarrassingly low-tech: turn off the sedation and see if the patient can breathe on their own. Done as a coordinated daily ritual, the spontaneous awakening trial (SAT) paired with the spontaneous breathing trial (SBT) — the "wake up and breathe" protocol — gets patients off the ventilator days sooner. The nurse and respiratory therapist run it, and the nurse's judgment is at the center of it.

Two trials, done in order, every day

The protocol has two distinct halves, and the order matters. The spontaneous awakening trial comes first: stop the sedation and let the patient wake up. The spontaneous breathing trial comes second: with sedation off and the patient awake enough to participate, minimize ventilator support and see whether they can carry their own breathing. Pairing them is the whole point — a patient snowed on a sedation infusion can't demonstrate they're ready to breathe, so you can't judge the lungs until you've lifted the sedation. The landmark "Awakening and Breathing Controlled" trial showed that coordinating the two got patients ventilator-free sooner and even improved survival compared with the breathing trial alone.

The SAT: safety screen, then turn it off

You don't just yank the sedation on every patient every morning — you screen first. A patient is not a candidate for the awakening trial that morning if they are actively receiving sedation to control something dangerous: ongoing seizures, alcohol withdrawal being treated, active agitation that risks self-extubation, escalating pressor requirements, signs of raised intracranial pressure, or a patient on a paralytic. If the safety screen is clear, sedation is stopped (or, for some analgesia, held per protocol) and the patient is allowed to wake.

SAT failure — when to restart sedation

The awakening trial is failed, and sedation is restarted (typically at half the prior dose, then titrated), if the patient shows sustained distress: anxiety or agitation that won't settle, a respiratory rate climbing and staying above roughly 35, a falling oxygen saturation, a new arrhythmia, or clear signs of respiratory distress or acute physiologic stress. The nurse is the one who watches this unfold at the bedside and makes the real-time call — a brief cough or a moment of restlessness as someone surfaces is not failure, but sustained distress is.

The SBT: can the patient carry their own breathing?

Once the patient is awake and calm off sedation, respiratory therapy and the nurse pass them to a spontaneous breathing trial — the ventilator support is dropped to a minimum (a low level of pressure support, or CPAP, or a T-piece, per your unit) so the patient is doing most or all of the work of breathing while you watch. A successful trial of roughly 30 minutes to two hours is strong evidence the patient may be ready for the tube to come out.

What a failing breathing trial looks like

You are watching for the patient who can breathe for a few minutes on their own but can't sustain it. The warning signs are a respiratory rate that climbs (a rate over ~35, or a rapid-shallow-breathing pattern), a falling saturation, a rising or falling heart rate and blood pressure, diaphoresis, accessory muscle use, and obvious distress or anxiety. The rapid shallow breathing index — respiratory rate divided by tidal volume in liters — is a classic bedside gauge; a high value (traditionally above ~105) predicts a patient who will tire out. If the patient fails, they go back on full support to rest, and the team tries again the next day rather than pushing an exhausted patient to extubation.

Passing the SBT is not the same as being extubated

A patient can pass the breathing trial and still not be ready to lose the tube, because the tube does two jobs: it moves air and it protects the airway. Before extubation the team also weighs airway protection — a strong cough, manageable secretions, and an adequate level of consciousness to keep the airway clear. This is why "passed the SBT" is a green light to consider extubation, not an order to pull the tube. The cuff-leak check, secretion burden, and mental status all feed the final decision, and post-extubation the nurse watches closely for stridor and respiratory failure that can send a patient back.

Where this fits: the ABCDEF bundle

The wake-up-and-breathe protocol is the "A/B" of the ICU Liberation ABCDEF bundle, the evidence-based framework for reducing the harms of prolonged ICU care: Assess and manage pain, Both spontaneous awakening and breathing trials, Choice of light sedation, Delirium monitoring and management, Early mobility, and Family engagement. The pieces reinforce each other — lighter sedation makes the awakening trial easier, which enables the breathing trial, which shortens the vent time, which cuts delirium and lets the patient get up and move. The nurse coordinating these elements each day is doing some of the highest-value work in the unit, even though none of it involves a new drug or device.

This piece pairs with the site's airway and vent guides, including initial ventilator settings after intubation and ventilator dyssynchrony, which cover the machine side of the same patient.