Breathing and Cough After a High Cervical Injury

Breathing with a high cervical injury: the problem is the cough, not the breath

The 70-year British study of mortality after traumatic spinal cord injury, published in Spinal Cord in 2017, tracked how people died across seven decades. Two of its findings should be read side by side.

Urogenital deaths — kidneys, urinary infection, urosepsis — fell from 32.8 per cent of deaths in 1944 to 1969 down to 8.7 per cent in 2005 to 2014. A reduction of roughly three quarters, achieved through better bladder management and renal surveillance.

Respiratory deaths went the other way. They rose to become the leading cause of death at 34.1 per cent in 2005 to 2014. And the age-standardised respiratory mortality rates across the study’s three periods were 712.4, then 878.6, then 793.3 per 100,000. The authors described respiratory mortality as showing no sustained improvement.

So across seventy years, medicine substantially solved the kidney problem after spinal cord injury and did not solve the lung problem. In 2014, respiratory death rates in this population still ran around five times the general population.

The AlphaBeta report prepared for SpinalCure Australia in 2020 reported that respiratory failure affects 70 per cent of people hospitalised with spinal cord injury.

Understanding why requires one anatomical insight, and it is the thing this guide is really about: after a cervical or high thoracic injury, the muscles that fail first are not the ones you breathe in with. They are the ones you cough with.

We support people with spinal cord injury across New South Wales, including respiratory and ventilation support under clinical plans written by the person’s treating team. We are not a respiratory service and nothing here is medical advice. Respiratory management after high cervical injury is specialist territory and belongs with a spinal unit and a respiratory physician.

The muscles, and which level takes which

Breathing in is mostly the diaphragm. Breathing out, at rest, is passive — the lungs and chest wall recoil. Coughing is active and forceful, and it needs the abdominal muscles and the internal intercostals to compress the chest and abdomen hard enough to generate flow.

Those muscles are supplied from different places:

Hence the old mnemonic taught in every spinal unit: C3, 4 and 5 keep the diaphragm alive.

Level by level, broadly:

C1 to C2. Above the phrenic nucleus. The diaphragm is not innervated. Long-term ventilatory support is generally required.

C3 to C4. Partial phrenic innervation. Highly variable — some people require full-time ventilation, some part-time, some wean entirely. Vital capacity is substantially reduced.

C5 to C8. The diaphragm generally works. Intercostals and abdominals do not. Breathing at rest is usually adequate; cough is severely impaired. Vital capacity typically well below normal.

T1 to T6. Diaphragm intact, partial intercostal function, abdominals absent or impaired. Cough remains weak.

T7 to T12. Progressively better expiratory function as abdominal innervation is retained.

Read down that table and the pattern is clear. Inspiratory function is preserved from C5 downwards. Expiratory function — cough — is impaired all the way down to the mid-thoracic level. A person with a C6 injury who breathes comfortably all day, holds a job, and has never needed oxygen, cannot clear their own chest when they get a cold.

Which is why secretions, not oxygen, are the thing that kills

The mechanism of respiratory death after spinal cord injury is usually not a failure to oxygenate. It is a failure to clear.

The sequence is predictable:

1. The person gets an ordinary upper respiratory infection, or aspirates slightly, or has a bad night.
2. Secretions increase.
3. They cannot generate the expiratory flow to clear them, because the cough muscles are denervated.
4. Secretions pool and plug small airways.
5. Segments of lung collapse — atelectasis.
6. Collapsed, wet lung becomes infected.
7. Pneumonia, in a person with no reserve and no ability to clear it.

That chain can run from a head cold to intensive care in under a week. It is also almost entirely interruptible, at steps three and four, by somebody who knows how to assist a cough.

This reframes the whole subject. The question for somebody with a cervical injury is not “can they breathe?” — mostly yes. It is “can somebody clear their chest at 3am, and does that person know how?”

The counterintuitive one: lying down can be better

In most respiratory conditions, sitting up improves breathing and lying flat makes it worse. After a cervical spinal cord injury, the reverse is frequently true.

The reason is the abdominal wall. In an intact person, abdominal muscle tone holds the abdominal contents in place, supporting the diaphragm from below and giving it a good mechanical starting position. After a cervical injury, abdominal muscles are flaccid. Sitting upright lets the abdominal contents sag forward and downward, dragging the diaphragm into a flattened, inefficient position.

Lying supine pushes the abdominal contents back up against the diaphragm, restoring a better dome and a better mechanical advantage. Measured vital capacity in people with tetraplegia is often higher lying down than sitting up.

This has three practical consequences:

Position matters and the obvious answer may be wrong. If somebody with tetraplegia is struggling to breathe, propping them bolt upright is not automatically correct, and their management plan should say what to do.

Abdominal binders help. A firm binder around the abdomen substitutes for the absent muscle tone, holds the contents in, and improves the diaphragm’s position. Binders are routinely prescribed for this reason and improve vital capacity and voice volume in many people with tetraplegia. They also need to fit properly and be checked for skin pressure.

A loaded abdomen compromises breathing. Significant constipation or faecal impaction distends the abdomen and measurably reduces respiratory capacity in people who have very little to spare. This is one of the direct links between a bowel programme that is not working and a respiratory admission.

What is available, and what each thing does

Abdominal binder. As above. Simple, cheap, under-used.

Assisted cough — also called a quad cough. A trained person applies firm, timed pressure to the abdomen or lower chest, synchronised with the person’s own attempt to cough, substituting for the absent abdominal muscles. Done correctly it substantially increases expiratory flow and clears secretions. Done at the wrong moment it achieves nothing.

This is the single most important practical skill for anybody supporting a person with a cervical injury, and it must be taught and signed off by a physiotherapist on that specific person, because technique, hand position and contraindications are individual. Contraindications matter — it is not performed over an unstable fracture, a recently placed inferior vena cava filter, or an acute abdomen without clinical clearance.

Breath stacking and lung volume recruitment. Using a bag and one-way valve, or glossopharyngeal breathing, to stack several breaths and achieve a larger inspired volume than the person can take alone. A bigger breath in produces a more effective cough out, and regular lung volume recruitment maintains chest wall compliance over years. Taught by a physiotherapist and done daily by many people as routine maintenance.

Mechanical insufflation-exsufflation — a cough assist machine. Delivers a positive pressure breath in and then rapidly switches to negative pressure, mechanically simulating a cough. Highly effective for secretion clearance. It is the single most valuable piece of respiratory equipment many people with high cervical injuries own, and the argument for funding it rests on comparing its cost with one intensive care admission.

Non-invasive ventilation. A mask-delivered ventilatory support, used overnight or part-time. Many people with high cervical injuries use nocturnal non-invasive ventilation and are entirely independent of it during the day.

Tracheostomy and invasive ventilation. For people requiring long-term full ventilatory support, or whose secretion burden cannot be managed non-invasively.

Diaphragm pacing or phrenic nerve stimulation. An implanted stimulator that drives the diaphragm directly. Suitable for a specific group — generally those with injuries above the phrenic nucleus whose phrenic nerves and diaphragm remain intact and viable, which has to be tested. For those it suits it can mean freedom from a mechanical ventilator for part or all of the day, which changes speech, smell, mobility and the experience of living. It is a specialist assessment worth asking about if it has never been raised.

Suction. Airway suctioning, under a clinical plan, where cough assist is insufficient.

Sleep, which nobody checks

Sleep-disordered breathing is substantially more common after cervical spinal cord injury than in the general population, and it is routinely undiagnosed.

Several factors combine: reduced respiratory muscle function, altered upper airway tone, the supine position, weight gain that frequently follows injury, and some medications used for spasticity and pain that depress respiratory drive.

The consequences are the ones you would expect — daytime fatigue, impaired concentration and memory, morning headache, low mood — and they are routinely attributed to the injury itself, to depression, or to deconditioning. Which means they go untreated for years.

If somebody with a cervical injury is persistently exhausted, sleeping badly, waking with headaches or struggling to concentrate, a sleep study is a reasonable thing to ask for. It is one of the higher-yield investigations in long-term spinal cord injury care and one of the least requested.

Voice, which is the part people grieve

This gets almost no attention in respiratory guidance and it is frequently what matters most to the person.

Speech is produced by air moving through the vocal cords on exhalation. Three things after a high cervical injury interfere with it.

Reduced volume and short phrases. With a small vital capacity and no abdominal support, there is simply less air to speak with. People run out mid-sentence, speak quietly, and find themselves unable to call out, raise their voice over background noise, or hold their own in a group conversation. The social cost of this is substantial and under-recognised — being unable to interrupt is a form of exclusion.

An abdominal binder frequently improves voice volume as well as vital capacity, for the same mechanical reason. It is a cheap intervention that people are often not offered for this purpose.

A cuffed tracheostomy diverts air away from the vocal cords entirely. Where the cuff is inflated, exhaled air leaves through the tube rather than passing up through the larynx, and the person cannot vocalise at all.

Ventilator timing. Speech has to be fitted around the ventilator’s cycle, which changes the rhythm of talking and takes practice.

What can be done about it, with a speech pathologist and the respiratory team:

• Cuff deflation, where it is clinically safe, allows air to pass the vocal cords and restores voice.
• A one-way speaking valve fitted to the tracheostomy directs exhaled air up through the larynx. For many people this is the single intervention that gives speech back.
• Ventilator adjustment to support longer exhalation and more usable speech time.
• Glossopharyngeal breathing, sometimes called frog breathing, which some people learn to use both for voice and for a bigger breath.
• Communication technology where speech is not achievable — eye gaze, switch access, voice banking before a voice is lost.

The reason to push on this is that voice is how a person directs their own support. Somebody who cannot speak audibly cannot correct a worker mid-transfer, cannot say stop, and cannot manage their own household. Restoring voice is restoring control, and it should be pursued as hard as any other part of the respiratory plan.

The first weeks, and why the level can move

Worth knowing for families in the acute phase, because it is frightening and frequently unexplained.

In the days after an acute cervical injury, swelling in and around the cord can cause the functional level to rise temporarily — a person admitted with a C5 injury may behave neurologically like a C4 for a period. Where that crosses the phrenic nucleus at C3 to C5, it can mean needing ventilatory support that was not needed on admission and may not be needed later.

This is also why classification in the first days is unreliable and why early grading is not a prognosis. As oedema settles, function frequently returns.

The practical implication for families: a ventilator in week one does not mean a ventilator forever. Many people are weaned entirely, and weaning from ventilation after cervical injury can take weeks or months and is a specialist process. Ask the spinal unit directly what the expected trajectory is rather than reading the first week as the final answer.

Preventing the admission

Most respiratory crises after spinal cord injury are the end of a predictable chain, which means there are several places to break it.

Vaccination. Influenza annually, pneumococcal and COVID-19 as recommended for the individual. For somebody who cannot clear their chest, a vaccine-preventable respiratory infection is a disproportionate threat. Household members and workers being vaccinated matters too.

Not working while sick. A support worker with a cold should not be on shift with somebody who has a C4 injury. This is harder than it sounds in a sector with chronic staffing shortages, and it requires a named decision-maker and a backfill plan or it will be ignored.

Daily lung volume recruitment, where prescribed. Maintenance, not treatment.

A working bowel programme, because abdominal distension costs capacity that is not available.

Smoking. The honest conversation. Risk is disproportionate for somebody with no respiratory reserve and no cough.

Weight. Weight gain after injury reduces respiratory capacity and worsens sleep-disordered breathing.

Seating and posture. Progressive scoliosis and poor seated posture reduce lung volumes over years. This is a seating review question.

Baseline measurements on file. The person’s usual vital capacity, their usual oxygen saturation, their usual cough effectiveness. Without a baseline, nobody can tell whether today’s numbers are bad.

A written winter plan. What happens when the person gets a cold: increase cough assist frequency to what, start what, ring whom, at what point go to hospital. Agreed in advance with the respiratory team and physiotherapist, in the file, and known to every worker. This document prevents more admissions than anything else in this guide.

The staffing question, honestly

Supporting somebody with a high cervical injury is not a task that competent generalist workers can pick up from a handover.

At minimum, the team needs:

• Every worker on shift able to recognise respiratory deterioration against that person’s baseline, and to escalate without hesitating.
• Enough workers trained and signed off in assisted cough that there is always one rostered, including nights, weekends and when the regular team is on leave. A roster where only two people can assist a cough is a roster with a predictable failure.
• Competency in the equipment the person uses — cough assist, non-invasive ventilation, suction — assessed on that equipment, not described in an induction.
• Written escalation thresholds specific to the person.
• Redundancy in equipment and power, because this is life-sustaining equipment.

This is high intensity support in the NDIS sense, and it requires the provider to have demonstrated competency frameworks, clinical oversight and a current plan from the treating team. The practical test to apply to any provider is simple: ask how many of the workers rostered to this person this month have been individually signed off in assisted cough by a physiotherapist, and ask to see the record.