Review Article

Near hangingNick Adams

Emergency Department, Royal Melbourne Hospital, Parkville, Victoria, Australia

Emergency Medicine (1999) 11, 17–21

Correspondence: Dr Nick Adams, Frederick V’s Veg, 15–25, Osterbro, Copenhagen, Denmark. Email: <altron@ozemail.com.au>

Nick Adams, MB, BS, Senior Registrar.

Abstract

Objectives: To review the literature on near hanging, focusing on the pathophysiology, and relatingthis to the clinical features and management.

Methods: English language articles published in the past 15 years and major textbooks ofemergency and forensic medicine were searched. Eight case series and six relevant singlecase reports were identified. Only articles concerned with non-judicial near hanging werereviewed. Data concerning the incidence of cervical spine injury, laryngeal injury,pulmonary complications and mortality were extracted. Not the case series documentedthe presence or absence of all these factors, resulting in differing total patient numbers ineach category. Unusual complications of near hanging were documented from casereports.

Results: Cervical spine injury occurred in four of 689 patients (0.6%). Pulmonary complicationsoccurred in 15 of 133 patients (11%). The in-hospital mortality rate was 23% (29 deaths of128). No clinically significant laryngeal injuries were reported. Unusual complicationsdocumented included hyperthermia, status epilepticus, carotid artery dissection,subarachnoid haemorrhage and pneumoperitoneum.

Conclusions: Cervical spine injury, although uncommon, does occur in near hanging, and emergentairway management should take this into account. Laryngeal injury sufficiently severe tointerfere with endotracheal intubation does not appear to occur. Cerebral oedema,aspiration pneumonia and acute respiratory distress syndrome are the commonestin-hospital complications. Management of near hanging involves establishment of a safeairway, plus treatment of pulmonary and cerebral oedema along standard lines.In-hospital mortality remains high.

Key words: airway management, cervical spine injury, near hanging.

Introduction

Hanging is a prominent cause of suicidal death inAustralia and New Zealand. The majority of hangingvictims are already dead when discovered, soprevention is obviously the only method that willreduce the mortality rate substantially. Means ofsuicide prevention are beyond the scope of this article,

which instead focuses on the pathophysiology andmanagement of near hanging.

Methods

A Medline search was performed using the keyword‘hanging’ on all English language publications in the

past 15 years. The cited references of articles obtainedwere examined to find other relevant publications. Inaddition, major textbooks of forensic and emergencymedicine were studied.

Definition

Hanging can be defined as death due to externalpressure on the neck, the force applied being due tosuspension of some, or all, of the body weight. Thisdefinition excludes manual strangulation and otherforms of blunt neck trauma such as the ‘clotheslineinjury’, where the external pressure is not due tosuspension. ‘Near hanging’ is a term used to refer tothose patients who survive a hanging injury longenough to reach hospital, being analogous to the term‘near drowning’.1

Aetiology

Hangings in the past were broadly categorised intojudicial and non-judicial. There are good reasons tobelieve that the patterns of injury in these two formsof hanging differ.1 Judicial hanging was previously apopular method of state-sponsored execution, but hasbeen supplanted by other more efficient means ofexecution in most places where the death penalty stillexists. Typically, 2.54 cm braided hemp was used asthe ligature with careful placement of the knot behindthe mastoid process. A drop equivalent to the victimsheight was effected by the sudden opening of a trap-door beneath the feet, and there was always completesuspension of the victim’s weight.2 These specificconditions are rarely found in non-judicial hangings,where the ligature used is often whatever is at hand(including rope, electrical cord or a trouser belt); anddrops equivalent to the victim’s height are almost neverencountered so suspension is more often incompletethan complete.3 Because of these differences betweenjudicial and non-judicial hanging, and because theformer is no longer performed in Australia, this articleconcentrates on non-judicial hanging.

Non-judicial hanging most often occurs as the resultof an intentional suicide or parasuicide bid but mayoccasionally be accidental.1 Hanging as a method ofsuicide is favoured by those in legal detention, withindigenous Australians and young males being also atparticular risk.3 Accidental hanging is rare but canoccur, for instance when clothing is caught inmachinery,4 when infants become entangled in therestraining straps of strollers, or even during bungee

jumping.5 Very occasionally, accidental hanging occursin the setting of autoeroticism, where the victimobtains sexual pleasure from partial asphyxiation butinadvertently becomes self-strangulated.6

Incidence

Hanging is the second most common cause of suicidaldeath in Australia3 and the most common in NewZealand.7 Approximately one quarter of all suicidaldeaths are due to hanging, with only the proportiondue to carbon monoxide poisoning being of a compar-able magnitude. Almost 90% of hanging victims aremales between the ages of 15 and 35 years, about one-third have a history of psychiatric illness, and nearly50% have a history of drug abuse or alcoholism.3

Pathophysiology and clinical features

The mechanism of injury in hanging is a combinationof axial traction and external pressure on the neck.The anterior neck region is uniquely vulnerable toinjury from external pressure because it contains anumber of vital structures in a relatively confined andunprotected space. The spinal cord is also at its mostvulnerable here, the cervical spine being more mobile,but less stable than the thoracic and lumbar regions ofthe vertebral column.8

Structures at risk in hanging include: the veins andarteries of the neck, the carotid body, the larynx and itsassociated cartilages and the cervical spine. Secondaryinjury to the brain is the main cause of early death,whereas pulmonary complications are mainly respon-sible for delayed mortality.

Injury to vascular structuresThe jugular veins lie superficially in the neck, onlypartially covered by the sternocleidomastoid muscles,and are thus vulnerable to compression. Venousobstruction, and subsequent stagnant cerebralhypoxia, has been proposed8 as the initial event in mosthangings, but arterial obstruction is likely to play amore important role.8 Loss of consciousness isreported to occur as early as 15 s after suspension, andan effect as rapid as this is unlikely to occur due tovenous obstruction alone.9 Only slightly greater forceis required to obstruct the carotid arteries,4

approximately 3.5 kg in an adult, according to earlyexperiments (compared with approximately 2 kg forthe jugular veins).9 The constrictive force in near

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hanging is likely to exceed this easily, even with onlypartial suspension of the victim’s body weight. Incontrast, a force of at least 15 kg is needed to obstructthe trachea.10 Arterial spasm may also contribute to theeffects of external pressure.8 Traction on arterialstructures during hanging can produce intimal tears,and arterial obstruction. These tears occasionally affectthe intracranial parts of the carotid arteries, causingbasal subarachnoid haemorrhage.11 Compression ofthe carotid bodies, and subsequent reflex bradycardia,has been proposed as a contributing factor in somehanging deaths.12

Unlike the carotid and jugular vessels, the vertebralarteries are well protected in their course through thetransverse foraminae of the cervical vertebrae. How-ever, obstruction of the vertebral arteries may stilloccur, either with or without cervical spine injury. Withforceful neck movements, especially in those individ-uals with degenerative disease of the cervical spine,kinking or spasm of the vertebral vessels has beendescribed, and this mechanism may operate in somehanging injuries.12

Laryngeal injuryFractures of the bony and cartilaginous anterior neckstructures are common, but not invariable, features ofhanging injuries.13 Thyroid cartilage fractures are themost common, with fracture of the hyoid bone andcricoid cartilage being seen less often. Damage to thesestructures seems to be more common in patients over40 years of age, and in cases where the ligature used inthe hanging is narrow rather than broad. Significantsoft-tissue injury to the larynx occurs inconsistently,both with and without fracture.11

The clinical significance of these laryngeal injuries,and the exact role of airway obstruction in hanging, isunclear. Certainly, many hanging victims exhibit nosigns of laryngeal damage at autopsy.11,13 In addition,there are several case reports of hanging deaths inpatients with tracheostomies, where the ligature wastied above the level of the stoma.12 However, a ligatureplaced above the thyroid cartilage may force the base ofthe tongue upwards to obstruct the airway, and such amechanism may not be detectable at post-mortem.10 Itappears that upper airway obstruction contributes tocerebral hypoxia due to ischaemia, but that it is not anessential component.

Cervical spine injuryCervical spine damage has been well documented injudicial hangings, where both bony injuries such as the

Hangman’s fracture and purely ligamentous injuriesoccur.2 However, these injuries seem to be uncommonin non-judicial hanging (Table 1). A different mechan-ism of injury occurs in judicial hangings, where thelength of drop is typically equivalent to the victim’sheight, and where suspension is always complete. Innon-judicial hanging, there is often no significantdrop,14 and suspension is often incomplete.3 Thismeans that the axial traction component of the hang-ing injury is far less, and this difference probablyexplains the much lower incidence of cord injury.

Spinal cord injury in the absence of vertebralcolumn instability has rarely been described, includingcentral cord syndrome, presumably caused by forcedhyperextension in a patient with pre-existing cervicalspondylosis,.15 Cord injury without vertebral columndamage is an undescribed but theoretical risk in youngchildren.

Secondary cerebral injuryWhether due to ischaemia or asphyxia, cerebralhypoxia causes a diffuse brain injury which oftenmanifests as cerebral oedema. Obstruction of cerebralblood flow would seem to be incomplete in mostsurvivors of hanging. Irreversible brain damage occurswithin 5–6 min of complete cessation of cerebral bloodflow, whereas hanging suspension times of up to 30min with complete recovery of neurologic functionhave been documented.14

The cerebral hypoxic injury is not always evenlydistributed, due to variation in both the sensitivity ofvarious brain tissues to hypoxia, and local variations inblood flow. Transient hemiparesis,14 and cerebralinfarction11 after near hanging injury have been notedin a few cases. Focal cerebral deficits may also occur,due to arterial dissection or spasm, or subarachnoidhaemorrhage.

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Near hanging

Table 1. Incidence of cervical spine injuries in near hanging

No. injuries No. patients Reference

0 3 230 7 12 306 211 101 22 1 233 110 39 14

Total 4 689 (0.6%)

Pulmonary complicationsAdult respiratory distress syndrome (ARDS) has beenrecognised as a complication of near hanging injuryfor many years (Table 2), although the exact patho-genesis is unknown.16 A centroneurogenic mechanismhas been proposed, ARDS being seen not uncommonlyin other forms of cerebral injury. Another possiblemechanism is the generation of large, negative intra-thoracic pressures, due to attempted inspiration in thepresence of upper airway obstruction.17

As with any other disorder associated with loss ofconsciousness, aspiration of gastric contents mayoccur in near hanging.1

Other complicationsHyperthermia has been described as a complication ofnear hanging,19 as has status epilepticus.20 A case oflower oesophageal rupture, in a near hanging victim,has been ascribed to traction on the oesophagus,20 butattempted vomiting against an obstructed upperoesophagus seems a more likely explanation. Tardieu’sspots (facial petechiae) and subconjunctival haemor-rhages, both due to venous hypertension, are variablypresent but are of no clinical consequence.1

Management

Initial management at the scene of the near hanginginvolves immediate relief of suspension and removal ofthe ligature. As with any other trauma situation,attention should then be directed toward the airway,breathing and circulation. Depending on the suspen-sion time and the degree of hypoxia, some patientsmay rapidly resume spontaneous ventilation andregain consciousness. Others will require airwaymanagement techniques, up to and including endo-tracheal intubation, and artificial ventilation. Some

authors recommend that precautions be taken toprotect the cervical spine,17,21 while others do not.1,8,14,22

Although the incidence of cervical spine injury is verylow among patients who have not sustained asignificant drop, and who do not have pre-existingcervical spine disease, accurate information aboutthese risk factors is usually not available in theemergency situation. It may be prudent to treat all nearhanging victims in the same way as other traumapatients, by assuming that they have an unstablecervical spine until proven otherwise.

Due to the risk of aspiration and the high incidenceof cerebral oedema, all patients with significantlyimpaired conscious state should receive rapid-sequenceendotracheal intubation and be mechanically ventilatedas soon as is practicable. In-line immobilization of thecervical spine should be performed during intubationand excessive motion of head and neck avoided.Generally, orotracheal intubation in the near hangingpatient is not complicated by any anatomical distortiondue to laryngeal trauma.17

Patients who do not require immediate intubationshould be closely observed for at least 24 h because ofthe small but not insignificant risk of late airwayobstruction due to soft tissue swelling.8,14

General recommendations for the management ofcerebral oedema include nursing in a 30 degree head-up position, gentle fluid restriction and a moderatedegree of hyperventilation (PaCO2, 30–35 mmHg).1,8,7,23

Other treatments, such as the administration of man-nitol, diuretics, anticonvulsants and corticosteroids, arecontroversial.4,8 Management of ARDS and aspirationpneumonia should be along usual lines, with the oneproviso that high levels of positive end-expiratorypressure (PEEP) may worsen the intracranial hyper-tension associated with cerebral oedema.22

Patients with persistent focal neurologic signsrequire investigation. A computed tomography (CT)scan of the brain may reveal subarachnoid haemor-rhage or (after a few days) cerebral infarction. Imagingof the carotid and vertebral arteries may be indicatedin cases where there is suspicion of arterial dissection.In the absence of focal neurologic signs, the diagnosticyield from routine imaging of the brain in nearhanging patients seems to be low. Van de Krol et al.performed CT scans on eleven unselected near hangingvictims, detecting only a small subarachnoid haemor-rhage in one.14 Bautz detected cerebral oedema in oneof three patients scanned.23

Patients with a pattern of neurologic injuryconsistent with an upper cord injury require CT or

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Table 2. Incidence of pulmonary complications (pneumonia orARDS) in near hanging.

No. pulmonary No. Reference complications patients

0 3 232 7 12 17 178 67 223 39 14

Total 15 133 (11%)

ARDS, adult respiratory distress syndrome.

magnetic resonance imaging (MRI) scanning of thecervical cord, even in the absence of a bony injury tothe cervical vertebrae on plain X-ray. This is particu-larly true in children, and in those with degenerativecervical spine disease.

All patients who present following attemptedsuicidal hanging should receive psychiatric evaluationand appropriate follow up.

Conclusion

Hanging has a pre-hospital mortality rate of greaterthan 50%.21 Those patients who survive to reachhospital should be treated aggressively, their survivalrate being approximately 77% (Table 3). Prognosis isnot necessarily related to the initial state atpresentation. There are several reports of patients whoarrived at hospital with a Glasgow Coma Scale score ofthree, and subsequently made a full neurologicrecovery.14, 23

The main long-term complications of near-hangingare neuropsychiatric. Short-term memory impairment,psychoses and dementia have been described,12 as hasspontaneous remission of chronic depression.1

Accepted 19 October 1998

References

1. Howell MA, Guly HR. Near hanging presenting to an accidentand emergency department. J. Accid. Emerg. Med. 1996; 13:135–6.

2. Wallace SK, Cohen WA, Stern EJ, Reay DT. Judicial hanging:

Postmortem radiographic, CT, and MR imaging features withautopsy confirmation. Radiology 1994; 193: 263–7.

3. Cooke CT, Cadden GA, Margolius KA. Death by hanging inWestern Australia. Pathology 1995; 27: 268–72.

4. McHugh TP, Stout M. Near-hanging injury. Ann. Emerg. Med.1983; 12: 774–6.

5. Hite PR, Greene KA, Levy DI, Jackimczyk K. Injuries resultingfrom bungee-cord jumping. Ann. Emerg. Med. 1993; 22: 1060–3.

6. Cooke CT, Cadden GA, Margoulis KA. Autoerotic deaths: Fourcases. Pathology 1994; 26: 276–28.

7. Anon. Mortality and Demographic Data 1993. Ministry ofHealth, New Zealand, 1995.

8. Mant AK et al. Taylor’s Principles and Practice of MedicalJurisprudence. Edinburgh: Churchill Livingstone, 1984.

9. Rentoul E, Smith H. Glaistners Medical Jurisprudence andToxicology. Edinburgh: Churchill Livingstone, 1973.

10. Rosen P, Barkin R. Emergency Medicine: Concepts and ClinicalPractice. St Louis: Mosby Year Books, 1997.

11. Samarasekera A, Cooke C. The pathology of hanging deaths inWestern Australia. Pathology 1996; 28: 334–8.

12. Berlyne N, Strachan M. Neuropsychiatric sequelae of attemptedhanging. Br. J. Psychiat. 1968; 114: 411–22

13. Morild I. Fractures of neck structures in suicidal hanging. Med.Sci. Law 1996; 36: 80–4.

14. Vander Krol L, Wolfe R. The emergency departmentmanagement of near-hanging victims. J. Emerg. Med. 1994; 12:285–92.

15. Ahuja J. Central cord syndrome resulting from near-hanginginjury. CMAJ 1987; 137: 221–2.

16. Fischmann CM, Goldstein MS, Gardner LB. Suicidal hanging:An association with the adult respiratory distress syndrome.Chest 1977; 71: 225–7.

17. Kaki A, Crosby ET, Lui A. Airway and respiratory managementfollowing non-lethal hanging. Can. J. Anaesth. 1997; 44: 445–50.

18. Calvanese JC, Spohr MH. Hyperthermia from a near hanging.Ann. Emerg. Med. 1982; 11: 152–5.

19. Dinsmore W, Crane J, Callender ME. Status epilepticus and nearhanging. Postgrad. Med. J. 1985; 61: 519–20.

20. Rodriguez AL, Rodriguez FF, Julia JA, Jerez V. Pneumo-peritoneum associated with suicidal hanging. Chest 1993; 110:1300 (letter).

21. Aufde-heide TP, Aprahamian C, Mateer JR et al. Emergencyairway management in hanging victims. Ann. Emerg. Med.1994; 24: 879–84.

22. Sternbach G, Bresler MJ. Near-fatal suicidal hanging. J. Emerg.Med. 1989; 7: 513–16.

23. Bautz P, Knottenbelt JD. Successful resuscitation from suicidalhanging: Report of three cases. Injury 1994; 25: 111–12.

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Table 3. Hospital mortality in near hanging

No. deaths in hospital No. patients Reference

24 67 220 7 10 3 232 12 243 39 14

Total 29 128 (23%)