Manual Strangulation Injury

Manual strangulation is compression of the neck by the hands or forearm, with occlusion of the airway and neck vessels. It is common in domestic violence and sexual assault and is a strong predictor of later homicide in abused partners.

Epidemiology. A large share of women assaulted by a partner report strangulation, and about half of those assaulted have no visible external injury. Fatal strangulation often follows previous non-fatal events.

Mechanism. Pressure of 4 kg occludes the jugular veins, 11 kg the carotid arteries and 15 kg the trachea. Loss of consciousness can occur in 5 to 10 seconds, and death in a few minutes.

Pathophysiology. Cerebral hypoxia, venous congestion, carotid sinus reflex effects, laryngeal and hyoid fracture, carotid and vertebral artery dissection with delayed stroke, and delayed airway oedema or pulmonary oedema.

Presentation includes neck pain and tenderness, finger shaped bruising or scratches, petechiae of the face, scalp, conjunctivae, ears and mouth, subconjunctival haemorrhage, voice change, hoarseness, cough, swallowing pain, dyspnoea, neck swelling, loss of consciousness, urinary or faecal incontinence, memory loss, headache, dizziness, visual change and anxiety. The absence of external signs does not exclude serious injury.

Red flags.

• Loss of consciousness, incontinence or amnesia.
• Voice change, stridor, dysphagia or neck swelling.
• Focal neurological deficit, severe headache or visual change.
• Pregnancy, or a history of repeated strangulation.

Careful documentation of history and examination, with photographs. CT angiography of the neck for any red flag, neck findings, petechiae or loss of consciousness. CT larynx or flexible laryngoscopy for airway signs. MRI brain for neurological symptoms. ECG and troponin if palpitations or chest pain. Pregnancy test.

Differential diagnosis. Hanging, ligature strangulation, blunt neck trauma, intoxication, seizure and psychogenic symptoms.

Airway. Assess the airway repeatedly. Secure it early for stridor, voice change with swelling or respiratory failure, using an awake difficult airway approach and cervical spine care.

Observation. Admit or observe for 24 hours when symptoms or signs exist, since airway oedema, stroke and pulmonary oedema can appear hours to days later. Provide return advice, and a safe place to stay.

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

Symptom control. Analgesia with paracetamol 1 g every 6 hours (maximum 4 g daily, 3 g if under 50 kg or liver disease), and soft diet.

Forensic and safeguarding care. Document injuries with photographs and body maps, record the account in the patient's own words, preserve evidence, assess risk of repeat violence and homicide, and offer police, advocacy and shelter support in line with consent and law. Report where mandatory.

Monitoring. Voice, swallowing, breathing, neurological state and mood.

Referral and escalation. ENT, neurology, vascular and intensive care when indicated, forensic medicine and domestic abuse services.

Special groups. In pregnancy, assess the foetus. In children, report to child protection services. In patients with cognitive change, arrange follow up for brain injury.