Airway protection with cervical-spine control

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Airway assessment starts with patency, protection and ventilation as separate questions. Speech, noise, secretions, facial movement, mouth opening and neck appearance reveal obstruction or difficult anatomy. Respiratory rate, chest movement, oxygen saturation and carbon dioxide reveal ventilation. Consciousness, gag or cough, repeated vomiting and facial bleeding indicate whether the patient can protect the airway. A currently patent airway can still be unsafe when inhalational injury, neck haematoma or progressive oedema is likely.

Simple manoeuvres buy time but require reassessment. A jaw thrust limits neck movement better than head tilt, two-person suction may be essential in contaminated trauma, and appropriately sized adjuncts maintain pharyngeal patency. High-flow oxygen and assisted bag-mask ventilation should use a two-person seal with an airway adjunct when possible. Cricoid pressure is not cervical stabilisation and should be reduced or released if it obstructs ventilation or laryngoscopy.

Cervical-spine protection is a coordinated process, not a rigid collar alone. Ask a trained assistant to provide manual in-line stabilisation while the front of the collar is removed for laryngoscopy. Avoid traction. If the patient is combative because of hypoxia, correct oxygenation rather than fighting the collar. After the airway is secured, use appropriate head blocks and straps, inspect pressure areas and complete clinical and radiological clearance as soon as safely possible.

A rapid-sequence plan should be announced before drugs are given. Optimise pre-oxygenation, haemodynamics and position; identify the first device and operator, the oxygenation rescue after a failed attempt, and the threshold for emergency front-of-neck access. Videolaryngoscopy can improve glottic view while limiting force, but blood may obscure its camera. Repeated attempts cause hypoxia and oedema, so an early change of operator or technique is safer than persistence.

Confirmation is continuous. A sustained capnography waveform is the principal immediate evidence of tracheal ventilation; review the value and waveform rather than merely stating that carbon dioxide is present. Bilateral chest movement, auscultation, tube depth, pressure and oxygenation add information. If capnography is absent, treat the tube as misplaced until proven otherwise. If the waveform suddenly disappears, disconnect and inspect, ventilate manually, and work through displacement, obstruction, pneumothorax and equipment failure.

After intubation, prevent secondary injury. Secure the tube and cervical protection, establish ventilation appropriate to predicted body weight, provide sedation and analgesia, insert an orogastric rather than nasal tube if skull-base injury is suspected, and obtain chest imaging when it will not delay urgent intervention. Normoxia and normocapnia are usual goals; brief controlled ventilation changes may be used only for imminent herniation under senior direction.

Children desaturate quickly and need weight-based equipment and drugs. Pregnancy reduces oxygen reserve and airway oedema can make intubation difficult; ramping and early senior help are important. Older adults may have fixed cervical deformity, dentures and fragile skin, making neutral alignment individual. In all groups, airway decisions should preserve perfusion: induction can precipitate cardiovascular collapse in profound haemorrhage unless blood and a resuscitation plan are ready.

Key points

Ask the patient to speak while observing work of breathing; a clear answer supports current patency but does not predict whether swelling, bleeding or fatigue will worsen.
Open with jaw thrust, suction under direct vision and remove visible loose material; use an oropharyngeal airway only without a gag reflex and a nasopharyngeal airway cautiously when midface or skull-base injury is suspected.
Give high-concentration oxygen during critical illness, pre-oxygenate with the best tolerated technique and preserve spontaneous ventilation until the definitive plan is ready when anatomy is concerning.
Manual in-line stabilisation supports the head during airway work; remove or open the anterior collar section if it limits mouth opening, then reapply movement restriction after securing the airway.
Trauma rapid-sequence induction requires a named intubator, optimised position, suction, bougie or stylet, videolaryngoscope when available, rescue supraglottic airway and prepared front-of-neck kit.
Confirm tracheal placement with a sustained waveform capnography trace, chest movement and clinical assessment; colour change or misting alone is inadequate.
Use lung-protective ventilation, avoid routine hyperventilation and target oxygen and carbon dioxide to the clinical context, with particular care in traumatic brain injury.
Recheck tube depth, waveform, oxygen saturation and chest findings after every move because CT transfer, log roll and handover are common moments of displacement.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Mechanical obstruction

Blood, vomit, teeth, foreign material and posterior tongue displacement narrow or block the airway, particularly when consciousness and pharyngeal tone are reduced.

Anatomical disruption

Maxillofacial fracture, laryngeal injury, penetrating neck trauma, expanding haematoma and inhalational injury can distort landmarks and deteriorate rapidly after an initially patent interval.

Ventilatory failure

Brain injury, spinal cord injury, drugs, chest trauma and fatigue may preserve an open airway yet abolish effective ventilation or airway protection.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Progressive hypoxaemia
Obstruction and inadequate alveolar ventilation reduce arterial oxygen; agitation may progress to bradycardia, reduced consciousness and cardiac arrest if correction is delayed.
2
Hypercarbia and brain injury
Hypoventilation raises carbon dioxide, increases cerebral blood flow and can worsen intracranial pressure, while aggressive hyperventilation may reduce injured-brain perfusion.
3
Secondary airway swelling
Soft-tissue trauma, burns, fluid shift and repeated laryngoscopy increase oedema, converting a manageable early airway into a later impossible one.
4
Spinal movement risk
Uncontrolled flexion, extension or translation may aggravate an unstable cervical injury, but prolonged airway hypoxia is the more immediate and certain neurological threat.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Patent but threatened

Hoarseness, facial burns, progressive swelling, neck wound, surgical emphysema or expanding haematoma can precede complete obstruction and should trigger early senior planning.

Obstructed airway

Snoring, gurgling, stridor, paradoxical respiratory effort, poor air entry and inability to vocalise require immediate opening, suction and oxygenation.

Failed protection

GCS decline, repeated emesis, absent cough, copious blood or seizure makes aspiration and obstruction likely even if spontaneous ventilation continues.

Difficult laryngoscopy predicted

Limited mouth opening, disrupted anatomy, obesity, collar restriction, blood and cervical deformity should determine operator, device and rescue preparation.

Tube failure

No sustained capnography, unilateral ventilation, unexpected depth, gastric inflation, hypoxaemia or high pressure demands immediate reassessment rather than radiographic reassurance.

Cervical neurological concern

Midline pain, paraesthesia, weakness, priapism, diaphragmatic breathing or neurogenic-shock features require movement restriction and urgent spinal evaluation.

Red flags requiring action

Stridor, gurgling, inability to speak, expanding neck swelling, severe facial disruption, soot or progressive hoarseness indicates a threatened airway requiring early expert control.
Apnoea, exhaustion, cyanosis, severe hypoxaemia, a falling GCS or loss of protective reflexes makes airway intervention time-critical even if initial anatomy appears normal.
Absent sustained waveform capnography after intubation, sudden desaturation, high airway pressure or loss of chest movement requires immediate exclusion of oesophageal placement, displacement, obstruction and pneumothorax.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
First-line waveform capnographyFirst stepFirst line
Why
Confirm and continuously monitor tracheal ventilation.
Interpretation and limitations
A sustained exhaled waveform after several breaths supports tracheal placement; absent or lost waveform demands immediate correction, even during cardiac arrest when values may be low.
02
Pulse oximetry and blood gas
Why
Assess oxygenation, ventilation and metabolic consequences.
Interpretation and limitations
Saturation can lag after pre-oxygenation and does not measure ventilation; arterial gas defines carbon dioxide and acid-base state but must not delay airway rescue.
03
Portable chest radiograph
Why
Check depth and thoracic complications after stabilisation.
Interpretation and limitations
Confirm the tip is appropriately above the carina and look for bronchial intubation, pneumothorax and aspiration, while recognising radiography cannot replace capnographic placement confirmation.
04
Preferred adult cervical imagingPreferred
Why
Identify clinically significant fracture or instability.
Interpretation and limitations
Use NICE cervical-spine criteria and CT when indicated in adults; neurological abnormality attributable to cord injury may require MRI after CT and specialist discussion.
05
Flexible endoscopic assessment
Why
Evaluate suspected laryngeal or airway injury in a controlled setting.
Interpretation and limitations
ENT and anaesthetic specialists may inspect a stable, spontaneously breathing patient, but endoscopy must not delay securing a rapidly deteriorating airway.
06
CT angiography of the neck
Why
Define vascular or penetrating-zone injury when stable.
Interpretation and limitations
Use for appropriate blunt cerebrovascular or penetrating injury patterns after immediate airway and haemorrhage threats are controlled; a trip to CT is unsafe during uncontrolled obstruction.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Tension pneumothorax

Severe hypoxaemia, hypotension, unilateral reduced breath sounds and rising ventilation pressure may reflect pleural obstruction rather than failure of the tracheal tube.

Opioid toxicity

Bradypnoea, reduced consciousness and small pupils can follow opioids, but traumatic intracranial and ventilatory causes still require simultaneous exclusion.

Seizure or postictal state

Transient obstruction, hypoventilation and reduced responsiveness can follow seizure; glucose, brain injury and ongoing non-convulsive activity need consideration.

Laryngeal injury

Hoarseness, neck emphysema, haemoptysis, pain and a palpable laryngeal abnormality suggest disruption where conventional intubation can create a false passage.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01ImmediateOpen, clear and oxygenateFirst stepNoisy, obstructed or inadequately ventilated traumatic airway.

1Call for anaesthetic and trauma help, maintain manual in-line stabilisation, apply jaw thrust and clear blood, vomit or visible foreign material with effective suction.
2Give high-concentration oxygen and use correctly sized airway adjuncts; assist ventilation with a two-person bag-mask technique if spontaneous breathing is inadequate.
3DefinitiveTreat concurrent chest causes of failed oxygenation, optimise circulation with blood where haemorrhage is present and prepare the definitive airway before reserve is exhausted.
4Reassess speech, chest movement, saturation, waveform carbon dioxide when ventilating, mental state and haemodynamics after every manoeuvre.

02DefinitiveDeliver trauma rapid-sequence intubationDefinitiveProtection or ventilation is failing, or predictable deterioration makes delay unsafe.

1State roles and Plan A through emergency front-of-neck rescue, pre-oxygenate, position accessibly and remove the anterior collar while an assistant provides manual stabilisation.
2Use the most experienced available operator and appropriate videolaryngoscope, bougie or stylet; limit attempts and prioritise oxygenation between them.
3Confirm a sustained capnography waveform immediately, secure the tube, reassess bilateral ventilation and begin appropriate sedation, analgesia and lung-protective ventilation.
4If intubation fails, oxygenate with bag-mask or supraglottic device; if neither ventilation nor oxygenation is possible, proceed without delay to the rehearsed emergency front-of-neck technique.

03AftercareProtect airway and cervical spine during transferDefinitiveThe tube and physiology are currently stable enough for imaging or definitive care.

1Record tube type, depth, grade, waveform, drugs, complications and cervical precautions, and assign one clinician to airway observations during every movement.
2Reconfirm capnography, saturation, pressure, tube depth and chest findings immediately after trolley transfer, CT movement or patient repositioning.
3Complete cervical-spine assessment and imaging, replacing indiscriminate prolonged collar use with an individual clearance or protection plan.
4EscalationEscalate new hypoxaemia or pressure rise through a systematic tube, circuit and chest check before assuming sedation is inadequate.

Key medicines and prescribing safety1 treatment · regimens, roles and cautions

Prevents or corrects hypoxaemia during airway preparation, suction, ventilation and transfer while the mechanical cause is treated.

Medical oxygen

In critical trauma, start high-concentration oxygen through a reservoir mask at 15 litres per minute or deliver 100% oxygen during assisted ventilation, then titrate once reliable monitoring and physiology permit.

Do not allow concern about hyperoxia to delay treatment of critical hypoxaemia; once stabilised, avoid unnecessary prolonged high concentration and use blood gases when carbon-dioxide retention is possible.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Unrecognised oesophageal intubation

Ventilation of the stomach produces no sustained exhaled carbon-dioxide waveform and rapidly causes profound hypoxaemia unless the tube is removed and oxygenation restored.

Aspiration

Blood, gastric material and secretions entering the lung cause obstruction, chemical pneumonitis, infection and impaired gas exchange.

Ventilator-associated harm

Excess pressure or volume, unrecognised bronchial intubation and delayed pneumothorax can injure lung and worsen haemodynamics after apparently successful airway control.

Pressure and immobilisation injury

Poorly fitted collars and prolonged restriction can cause skin damage, impaired venous drainage, discomfort and unsafe agitation, particularly in frail patients.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Observe continuous waveform capnography, oxygen saturation, respiratory rate, airway pressure, delivered volume and haemodynamics after an advanced airway.
Document tube depth at teeth or gums and recheck it after each move, procedure and sudden clinical change.
Repeat neurological examination and inspect collar contact areas; movement restriction must not hide pressure injury or prevent access to a deteriorating airway.
Trend blood gases when ventilation is difficult, major chest injury exists or traumatic brain injury makes carbon-dioxide control important.
Record failed attempts and devices used so the receiving team understands swelling, trauma and the likely difficulty of reintubation.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

Oxygenation outranks immobilisation

Spinal movement should be minimised by skilled assistance, but a collar must never prevent lifesaving airway opening or ventilation.

Capnography is continuous evidence

A single initial trace is not enough; displacement can occur during every transfer and patient turn.

Blood defeats cameras

Videolaryngoscopy may improve view in many trauma airways, yet direct suction and an alternative technique remain essential when optics are contaminated.

Induction reveals shock

Positive pressure and induction drugs reduce compensatory tone and venous return, so an apparently stable bleeding patient can collapse at intubation.

Plan the exit before entry

Declaring the failed-airway threshold and preparing front-of-neck equipment prevents repeated low-value attempts during rapidly falling saturation.

11Common pitfallsFrequent interpretation and management errors.

01
Leaving a rigid collar closed when it prevents mouth opening for necessary airway treatment.
02
Using chest misting or auscultation without sustained waveform capnography to confirm intubation.
03
Repeating laryngoscopy without changing operator, device, position or oxygenation strategy.
04
Sending a threatened airway to CT before an expert definitive or rescue plan is established.
05
Forgetting haemorrhagic physiology when selecting induction timing and preparing post-intubation support.
06
Assuming a secured tube cannot displace during movement between resuscitation room, scanner and theatre.