As South Korea investigates the Halloween crowd crush tragedy that took over 154 lives on Saturday, 29 October, the Seoul National University Hospital maintains the most common cause of death to be compressive asphyxia.
What actually happened?
Over 1,00,000 people, huddled around the tiny streets of Itaewon, the district known for its nightlife. However, throngs of crowd and barely any space led to a crowd crush making disaster almost inevitable.
FIT spoke to cardiologists to understand how asphyxia can cause sudden cardiac arrests, thereby making crowd crushes deadly.
The Asphyxia-Crowd Crush Connection
"Asphyxia reduces oxygen supply to all parts of the body, including the brain, heart, and all vital structures. When the heart receives less blood supply, it is unable to pump enough blood to other tissues. That is why the heart stops, which is known as cardiac arrest in common parlance. So that is the cause of cardiac arrest in asphyxia," Dr Kayan Siodia, Consultant, Interventional Cardiology, at Mumbai's PD Hinduja Hospital & Medical Research Centre told FIT, explaining what could have happened in Seoul.
According to experts, while there is a misconception that people are killed in crowds because they crush each other, the real reason is actually suffocation due to asphyxia. What's the rationale?
“As people struggle to get up, arms and legs get twisted together. Blood supply starts to be reduced to the brain,” G Keith Still, a visiting professor of crowd science at the University of Suffolk in England told NPR.
“It takes 30 seconds before you lose consciousness, and around about six minutes, you’re into compressive or restrictive asphyxia. That’s generally the attributed cause of death – not crushing, but suffocation.”
This is what happened in South Korea, explains Dr Arun Kochar, a leading cardiologist associated with Fortis Healthcare.
"As it happened in South Korea, hundreds and thousands of people were stuck in narrow lanes. From the visuals you can see that there was no elbow space, and the sheer mass of people crumbling into each other – leading to suffocation, asphyxia. This also made women more vulnerable, since they are known to weigh lighter."
Does This Mean Women Are More Vulnerable?
According to The Korea Herald, a total of 98 women were killed in the Halloween tragedy, as compared to 56 men. Does this mean, women are more prone to asphyxia than men?
Speaking to The New York Times, Professor Still asserted that studies about this are inconclusive. However, he also noted: "Women, while they have smaller frames, have more body mass in their upper chest. If there is pressure exerted there, there is more mass pushing inward, being more detrimental for women.”
Dr Sisodia agrees.
"The studies are largely inconclusive. However, there are hypotheses that female lung capacity is much lower than male lung capacity, which could be a factor in these situations. Second, the body structure, weight, and muscle mass in women are always much lower than most men, which can contribute to women developing asphyxia faster than men."Dr Kayan Siodia, Consultant, Interventional Cardiology at Mumbai's PD Hinduja Hospital & Medical Research Centre
What If You Anticipate the Danger Of Asphyxia?
"Cardiopulmonary resuscitation (CPR) is of prime importance in such a situation. Everyone must know how to administer one. However, this must be administered within five minutes of the person being in distress. In a situation like South Korea, they could have been given oxygen and other life support. Timely medical assistance is needed," Dr Kochar told FIT.
According to Dr Siodia, the following steps need to be taken immediately, if you anticipate danger of suffocation.
First, try to find a way out, because in such a situation, everyone runs where the crowd goes, but it should be the opposite.
Second, when such an incident happens, there is always panic, and when panic sets in, one's breathing, respiratory rate, and heart rate all increase dramatically.
The important thing here is to stay calm so that one can make the most of whatever oxygen is available rather than increase the breathing rate and heart rate.
"Finally, if such a situation arises, it is critical to seek immediate medical attention for patients suffering from asphyxia because time is of essence for these patients."