Manual strangulation is one of the most lethal forms of intimate partner violence and demonstrates the abuser’s power and control over the victim. The brain will suffer an anoxic injury when the flow of oxygenated blood is stopped by occlusion of the carotid arteries. Strangulation victims report visual and auditory changes just prior to a loss of consciousness. The loss of bladder control indicates a deep anoxic insult to the brain of at least 15 seconds in duration. The loss of bowel control occurs with carotid artery occlusions of greater than 30 seconds. The jugular veins can be occluded with 4.4 psi, the carotids with 11 psi, and the trachea with 34 psi. Occlusion of venous return can cause capillary rupture from increased pressure and the development of petechial hemorrhage (Figs. 19.32, 19.33, 19.34). Petechial hemorrhages can develop in any vascularized tissue, including the brain. The most sensitive areas for petechial hemorrhage development include the conjunctiva, sclera, and intraoral mucosa. The use of an oral-pharyngeal scope (Fig. 19.35) often reveals vocal cord injury and the presence of petechial hemorrhage in the posterior pharynx. With simultaneous occlusion of both the carotid and vertebral arteries and venous systems, it is possible to induce fatal and nonfatal strangulation events without petechial hemorrhage. Victims can be fatally strangled without external evidence of trauma.
Strangulation Ligature Mark. Ligature marks from the wires of her husband’s “ear buds.” The victim sustained neurologic compromise from the compression of her carotids. (Photo contributor: William S. Smock, MD.)
Petechial Hemorrhage. Extensive facial petechiae are found above the area of neck compression in a nonfatal strangulation victim. (Photo contributor: William S. Smock, MD.)
Subconjunctival and Scleral Petechial Hemorrhage. Increased venous pressure from the occlusion of the jugular veins during manual strangulation results in ruptured capillaries. (Photo contributor: William S. Smock, MD.)
Petechial Hemorrhage in Posterior Pharynx. Petechial hemorrhage in the posterior pharynx is a common finding in victims of strangulation. (Photo contributor: William S. Smock, MD.)
Oral-Laryngeal Scope. An oral-laryngeal scope, equipped with a camera, is an excellent tool to document the extent of petechial hemorrhage in the pharynx and vocal cord injury in victims of strangulation. (Photo contributor: William S. Smock, MD.)
The application of external pressure to the neck, even without visible external trauma, can cause serious physical injuries and death. Asymptomatic dissections in both the carotid and vertebral arteries are a known complication ...