Near-Hanging Injury

Near hanging is hanging that is not fatal at the scene, with neck compression by a ligature or the body weight, causing airway obstruction, vascular compression, hypoxic brain injury and sometimes cervical injury. Complete suspension (typical) and partial suspension are distinguished.

Epidemiology. Hanging is among the commonest methods of suicide, and survivors are mostly young adults and adolescents. Outcome relates to the duration of hypoxia and cardiac arrest.

Mechanism. Death or injury results from carotid and jugular compression (loss of consciousness in seconds), airway obstruction and, in judicial or high drop hanging, fracture of the cervical spine. Arrest may follow reflex bradycardia or hypoxia.

Pathophysiology. Hypoxic and ischaemic brain injury, cerebral venous congestion, negative pressure pulmonary oedema after release of obstruction, and aspiration contribute. Carotid and vertebral artery dissection or intimal injury can cause delayed stroke. Laryngeal and hyoid fractures can cause delayed airway oedema.

Presentation ranges from alert patients with a ligature mark to deep coma, cardiac arrest, hoarseness, dysphagia, stridor, neck swelling, subcutaneous emphysema, petechiae, frothy sputum and focal neurological deficits. Spinal cord injury may be present.

Red flags.

• Loss of consciousness, stridor, voice change or neck swelling.
• Focal neurological signs, or a decreased level of consciousness out of proportion.
• Haemoptysis, subcutaneous emphysema or respiratory distress.

Airway and spinal assessment. Imaging: CT of the cervical spine, and CT angiography of the neck (for carotid and vertebral injury) in anyone with signs of vascular injury, neurological deficit, neck wound or loss of consciousness. CT head, chest radiograph (pulmonary oedema, aspiration), arterial gas, lactate, ECG, troponin, creatine kinase and toxicology. Flexible laryngoscopy if airway signs.

Differential diagnosis. Intoxication, primary neurological event, assault and strangulation, and primary cardiac arrest.

Airway. Immobilise the cervical spine. Secure the airway early, with an experienced operator, a difficult airway plan and awake fibreoptic technique when airway oedema is likely, because swelling can progress over hours. Delay may make intubation impossible.

Breathing. Oxygen, lung protective ventilation if intubated (6 to 8 mL/kg), PEEP for negative pressure pulmonary oedema, which usually resolves within 24 hours.

Circulation and cardiac arrest. Follow resuscitation care, with targeted temperature management after arrest (36 °C and fever avoidance for at least 72 hours), mean arterial pressure over 65 mmHg, normoxia and normocapnia.

Neurological care. Treat seizures: levetiracetam 60 mg/kg IV (maximum 4500 mg), or lorazepam 0.1 mg/kg IV (maximum 4 mg) for active seizure. Avoid hypotension, hypoxia and hypoglycaemia.

Vascular injury. Anticoagulation or antiplatelet therapy for arterial dissection, directed by stroke and vascular specialists after exclusion of intracranial haemorrhage: aspirin 300 mg then 75 to 100 mg daily, or heparin.

Observation. Observe for at least 6 to 24 hours for delayed airway oedema, aspiration pneumonia and pulmonary oedema, even if the patient looks well.

Psychiatric care. Psychiatric assessment of risk once medically stable, constant observation to prevent repeat self-harm, and treatment of any underlying disorder.

Monitoring. Airway, oxygen saturation, neurological state, ventilator pressures and urine output.

Referral and escalation. Intensive care, ENT and anaesthesia for the airway, neurology or neurosurgery for neurological injury, and psychiatry.

Special groups. In adolescents, safeguarding and family involvement. If the cause is not self-inflicted, handle it as an assault and preserve evidence.