Understanding Accessory Muscle Use for Student Nurses
Learn how to recognise accessory muscle use, understand why it can signal increased respiratory effort and connect this important observation with the patient's wider respiratory assessment.
What are accessory muscles of breathing?
Quiet breathing is normally driven mainly by the diaphragm and other primary respiratory muscles. When breathing becomes more difficult, additional muscles can be recruited to help expand or stabilise the chest. These are commonly described as accessory muscles of breathing.
Usually relatively effortless
At rest, a comfortable adult should not normally appear to be using large amounts of additional muscular effort to breathe.
More muscles are recruited
When respiratory demand increases, muscles around the neck, shoulders and chest may become visibly involved.
A sign of increased work
New or pronounced accessory muscle use may indicate that breathing has become more difficult for the patient.
What might accessory muscle use look like?
You may notice additional movement around the neck, shoulders or upper chest as the patient works harder to breathe. The important skill is recognising that the patient's breathing appears effortful.
Visible muscular activity
Muscles around the neck may become more prominent during inspiration.
Shoulder movement
The shoulders may rise noticeably as the patient attempts to increase chest expansion.
Marked respiratory effort
Breathing may look visibly laboured rather than smooth and comfortable.
Accessory muscle use becomes more important when other signs change
| Finding | What you may notice | Why it matters |
|---|---|---|
| Respiratory rate | Breathing becomes faster or changes significantly from baseline. | Increased rate plus increased effort can indicate growing respiratory demand. |
| Speech | The patient struggles to speak comfortably because of breathlessness. | Difficulty communicating may indicate significant respiratory compromise. |
| Oxygenation | Oxygen saturation or oxygen requirements change. | Interpret against the patient's prescribed target and overall condition. |
| Chest movement | Movement may appear exaggerated, reduced or unequal. | Chest movement provides additional information about breathing mechanics. |
| Breath sounds | Wheeze, crackles or reduced air entry may be present. | Auscultation findings can add information when interpreted in context. |
| Consciousness | The patient becomes confused, drowsy or less responsive. | Neurological change alongside respiratory distress is particularly concerning. |
Watch how respiratory effort changes over time
Accessory muscle use should be considered as part of a changing clinical picture. A patient may initially compensate for respiratory difficulty by working increasingly hard to breathe.
Breathing becomes difficult
The patient's respiratory demand begins to increase.
Effort increases
Respiratory rate and visible muscular effort may increase.
Accessory muscles become visible
Additional muscles may be recruited to support breathing.
Fatigue may develop
Prolonged respiratory effort may become difficult to sustain and requires careful reassessment.
Assess increased work of breathing systematically
Airway
Confirm airway patency and recognise signs of immediate airway compromise.
Breathing
Assess respiratory rate, depth, accessory muscle use, chest movement, oxygenation and relevant breath sounds.
Circulation
Assess pulse, blood pressure and peripheral perfusion.
Disability
Identify new confusion, drowsiness or reduced responsiveness.
Exposure
Consider temperature and other relevant findings while maintaining dignity.
Escalate
Obtain appropriate senior or emergency help according to local procedures when significant respiratory deterioration is suspected.
The patient looks like they are working harder to breathe
Example
A patient being treated for an acute respiratory illness becomes more breathless during your shift.
Their respiratory rate has increased. You notice their shoulders rising with each breath and increased muscular movement around the neck.
Rather than documenting only the respiratory rate, you recognise a wider pattern: increasing respiratory rate + visible accessory muscle use + worsening breathlessness.
You complete the appropriate ABCDE assessment and communicate the change promptly to the registered nurse.
Describe what you can see
Example escalation
“I'm concerned about Mrs Patel. She is more breathless than earlier, her respiratory rate has increased and she is now visibly using accessory muscles around her neck and shoulders when breathing.”
This gives the receiving clinician an objective description of the deterioration without assigning an unsupported diagnosis.
Errors to avoid
- Recording respiratory rate without looking at respiratory effort.
- Ignoring visible neck or shoulder muscle activity.
- Assuming normal oxygen saturation means breathing is comfortable.
- Failing to compare the patient's breathing with earlier assessments.
- Ignoring difficulty speaking because of breathlessness.
- Assuming reduced effort always means improvement.
- Delaying escalation while trying to determine the exact diagnosis.
Look → measure → connect → escalate
Breathing effort is an observation — not just an impression
Learn to notice how a patient breathes, connect visible effort with measurable observations and recognise when the pattern is deteriorating.
Explore Clinical Confidence →