Nursing care
Respiratory Failure nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 6 min read · Updated September 2026
Short answer
Respiratory failure means the lungs can no longer maintain adequate gas exchange, and it comes in two distinct forms. Type 1 is a failure of oxygenation — the PaO2 falls while CO2 stays normal or low. Type 2 is a failure of ventilation — CO2 rises because the patient cannot move enough air. Only type 2 improves simply by making the patient breathe more; type 1 needs oxygen delivery fixed, not just volume.
Recognising it at the bedside
Type 1 failure shows up as a patient working hard to breathe but not clearing anything — tachypnoea, accessory muscle use, restlessness, and a falling SpO2 despite oxygen. The lungs are full of fluid, collapsed alveoli, or shunted blood, so oxygen cannot cross into the capillaries no matter how fast the patient breathes. Think pneumonia, pulmonary oedema, ARDS, or a large PE.
Type 2 failure looks calmer at first and that is the trap. The patient may be drowsy, confused, or have a headache, with slow or shallow breathing rather than rapid gasping. CO2 is not being cleared, so it accumulates and depresses consciousness rather than provoking obvious distress. Causes include COPD exacerbation, opioid overdose, neuromuscular weakness, and severe asthma once the patient tires. A rising CO2 with falling respiratory rate is a sign the patient is losing, not winning.
Why the classic presentation misleads
Nurses are taught to watch for the gasping, tripod-positioned patient in respiratory distress, and that picture fits type 1 well. It does not fit type 2. A hypercapnic patient can look deceptively settled — sedated, somnolent, easy to mistake for someone finally resting after a long shift of breathlessness. That apparent calm is CO2 narcosis, not improvement.
The other trap is treating both types the same way. Giving high-flow oxygen to a type 1 patient is usually correct and often lifesaving. Giving the same oxygen strategy to a chronic type 2 patient, particularly one with COPD who relies on a hypoxic drive, can blunt their respiratory effort further and push CO2 higher still. The intervention that rescues one type of failure can worsen the other, which is why classification comes before treatment, not after.
Priority nursing actions
Confirm oxygenation and ventilation status together, not oxygenation alone. Pulse oximetry tells you about oxygenation only; it says nothing about CO2. An SpO2 of 94% on a patient who is hypercapnic and increasingly drowsy is not a reassuring number, it is an incomplete one. Get an ABG before assuming the picture is settled.
Position the patient upright where tolerated to maximise diaphragmatic excursion, and titrate oxygen to the ordered target rather than to a reflexive maximum, especially in known CO2 retainers. For type 2 failure, prioritise interventions that improve ventilation: reposition, encourage deep breathing, treat bronchospasm, reverse sedation if opioid-related, and prepare for non-invasive ventilation such as BiPAP if the patient is tiring. For type 1 failure, focus on the underlying cause of shunt or diffusion failure — diuresis for pulmonary oedema, antibiotics and positioning for pneumonia, anticoagulation for PE — while supporting oxygenation. Escalate early; both types can progress to arrest.
Labs and diagnostics to expect
Arterial blood gas is the defining test. PaO2 below roughly 60 mmHg on room air with normal or low PaCO2 points to type 1. PaCO2 above roughly 45–50 mmHg with a corresponding drop in pH (unless renal compensation has occurred) points to type 2. Expect the ABG to be repeated after each significant intervention, not just once on admission.
A chest X-ray helps distinguish the underlying cause — bilateral infiltrates suggest ARDS or oedema, focal consolidation suggests pneumonia, hyperinflation suggests COPD. Expect a chest CT or CT pulmonary angiogram if PE is suspected. Basic metabolic panel and lactate help assess whether hypoxia is causing tissue-level compromise. In chronic type 2 failure, a compensated pH with an elevated bicarbonate tells you the CO2 retention is longstanding rather than acute, which changes how aggressively you correct it.
Complications and their early signs
Untreated hypoxaemia leads to end-organ hypoperfusion: watch for new confusion, falling urine output, and rising lactate as early markers before frank hypotension develops. Cardiac dysrhythmias can follow, driven by hypoxia and acidosis together.
Untreated hypercapnia leads to progressive somnolence and eventually loss of airway-protective reflexes. A patient who was answering questions an hour ago and is now difficult to rouse has moved from compensated to decompensated type 2 failure, and that trajectory can end in respiratory arrest within a short window. Watch respiratory rate trends as closely as the absolute number — a rate falling from 28 to 10 is more alarming than a steady rate of 22, even though the lower number looks calmer on the monitor.
Teaching that changes outcomes
For patients with COPD or other chronic CO2 retention, teach pursed-lip breathing and the reasoning behind their prescribed oxygen flow rate — patients who understand why more oxygen is not automatically better are less likely to turn up their own home oxygen during a flare. Teach early warning signs specific to their disease: increased sputum, change in sputum colour, or new breathlessness on exertion that means calling for help rather than waiting.
For any patient recovering from an acute respiratory failure episode, teach smoking cessation resources if relevant, correct inhaler and nebuliser technique with a return demonstration, and the specific criteria for seeking urgent care — a change in level of alertness, worsening breathlessness at rest, or lips or fingertips turning blue. Family members should know these same triggers, since a hypercapnic patient may be too drowsy to recognise their own deterioration.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our respiratory practice questions are the closest set to what this page covers.
Common questions
What is the difference between type 1 and type 2 respiratory failure?
Type 1 is hypoxaemic failure — low PaO2 with normal or low PaCO2 — caused by problems getting oxygen across the alveolar-capillary membrane, as in pneumonia or ARDS. Type 2 is hypercapnic failure — high PaCO2, often with low PaO2 too — caused by inadequate ventilation, as in COPD exacerbation or opioid overdose. The distinction matters because increasing oxygen delivery treats type 1 but does not correct the ventilation problem driving type 2.
Why is a normal SpO2 not reassuring in respiratory failure?
Pulse oximetry measures oxygen saturation only, and cannot detect CO2 retention. A patient can have an acceptable SpO2 on supplemental oxygen while their PaCO2 climbs and their pH falls, becoming progressively drowsy from hypercapnia. An ABG is needed to see the ventilation side of the picture that oximetry misses.
Can giving too much oxygen make respiratory failure worse?
In patients with chronic type 2 failure who rely on a hypoxic drive to breathe, high-flow oxygen can blunt that drive and reduce respiratory effort, allowing CO2 to rise further. This does not mean oxygen should be withheld from a hypoxic patient; it means oxygen should be titrated to a target saturation rather than maximised, with close monitoring of mental status and CO2 trend.
How does respiratory failure typically appear on the NCLEX?
Expect scenario-based questions asking you to classify ABG results as type 1 or type 2, then select the priority intervention. A question describing a drowsy COPD patient with a rising PaCO2 is testing whether you recognise CO2 narcosis rather than mistaking sedation for improvement. Another common pattern tests positioning, oxygen titration, and recognising when non-invasive or invasive ventilation is indicated.
What is the first nursing action when respiratory failure is suspected?
Assess airway, breathing, and level of consciousness together, obtain an ABG, and continue pulse oximetry while recognising its limits. Position the patient to optimise breathing, apply or adjust oxygen per order, and notify the provider promptly rather than waiting for further deterioration.