What We Don’t See in the Shadows
BY MICHELLE JOHNSTON, MBBS
Some pathologies are like fiends, lurking in the shadows, often unseen, and certainly underrecognized. Nonfatal strangulation is one of those.
There’s nothing new about NFS as an act of violence and control, but it is only recently that we clinicians have understood what makes it unique.
All around the world, legislation is falling in line with NFS, with legal ramifications commensurate with its seriousness as a crime. We in medicine are now catching up with the law.
What is interesting, however, is understanding why we have been so slow to register NFS as the deadly act it is. We now know that a single episode of NFS increases a victim’s risk of being killed at the hands of that same perpetrator up to seven times over. It has been described as being on the edge of homicide, not just an act of violence but one of cold, calculating control. It says, “With my bare hands, I can take your life.” It takes not much more than the strength of a handshake to kill.
We have to parse the reasons we have been slow on the uptake. To start, we ask the wrong questions. If we inquire whether a victim has been strangled, she may not register the event for what it was, as though strangulation only occurs like it does in the movies. Instead, we should ask whether the patient has had any sort of pressure placed on the neck. Perhaps it was a knee, a weapon, or a ligature. We also need to ask questions aslant: “Did you black out, wake up on the floor, lose control of your bowels or bladder?” All of these are consequences of hypoxia.
The victim may not recall the event. Anoxia happens quickly, and the centers for memory can be affected rapidly. If this is not the first time, we may need to think about it in the same way as repeat concussion injury, with cumulative anoxic injury contributing to neuropsychiatric sequelae, including further memory loss and other cognitive changes.
Newest of the Old
We don’t appreciate the fact that less than 50 percent of victims have external signs of injury (ligature marks, abrasions, the classic petechial hemorrhage distribution, defensive scratch marks), leading us to underestimate the severity of the assault.
We don’t consider how little force it takes to cause serious injury and how quickly it can occur. The four mechanisms for potentially fatal outcomes in NFS are:
- Jugular venous obstruction can cause sudden severe venous congestion, and it takes less pressure than is required to open a can of soda to achieve this.
- Carotid artery compression still requires less force than a firm handshake, and loss of consciousness from hypoxia can occur within 10 seconds.
- Airway compression requires greater and more sustained force, but can still result in hypoxia, as well as aerodigestive injury.
- Carotid body compression or stimulation is more a postulated mechanism, and may cause bradyasystolic arrythmias.
We may overlook the important sequelae. Carotid artery dissection is uncommon but may be missed, resulting in long-term disability. The nature of NFS, with intermittent arterial compression with torsion from twisting movements, has been demonstrated to cause arterial injury. A CT angiogram needs to be requested if there is any suspicion at all.
We may not even get to the starting point. Victims of intimate partner and family violence may not feel able to answer our hurried, targeted questions. It is vital to leave a nonjudgmental, caring space wide open for the victims to speak and be believed.
NFS can be considered the newest of old conditions. By increasing our level of suspicion, asking the right questions in the right ways, we have it within our own hands to save a life.
Dr. Johnston is a board-certified emergency physician, thus the same as you but with a weird accent. She works in a trauma center situated down the unfashionable end of Perth, Western Australia. She is the author of the novel Dustfall, available on her website, http://michellejohnston.com.au/. She also contributes regularly to the blog, Life in the Fast Lane, https://lifeinthefastlane.com. Follow her on Twitter @Eleytherius, and read her past columns at http://bit.ly/EMN-WhatLiesBeneath.