In News:

The recent tragic stampede at a rally of TamilagaVetriKazhagam (TVK) in Velusamypuram, Tamil Nadu, resulted in 41 deaths, including nine children. Doctors have attributed most fatalities to compressive asphyxia, highlighting the dangers of overcrowded events in India.

What is Asphyxia?

Asphyxia, or asphyxiation, occurs when the body does not receive sufficient oxygen. Normally, respiration allows oxygen to circulate via blood to all cells while removing carbon dioxide. In asphyxia, inadequate oxygen can lead to unconsciousness, organ failure, or death.

Types of Asphyxia:

Medical literature classifies asphyxia into several types:

• Mechanical Asphyxia: Physical obstruction preventing normal breathing.
• Traumatic Asphyxia: Strong external force on the thoracic cavity causes blood to backflow to the brain.
• Perinatal Asphyxia: Insufficient oxygen before, during, or shortly after birth.
• Compressive Asphyxia: External pressure on the chest or abdomen prevents expansion of the lungs.
• Other Types: Include suffocation, chemical asphyxia, strangulation, and drowning.

Compressive Asphyxia in Crowds:

In large gatherings or stampedes, people can be pressed tightly against each other. The diaphragm, a key muscle for breathing, cannot contract effectively, preventing inhalation and exhalation. This leads to oxygen deprivation (hypoxia) and carbon dioxide buildup (hypercapnia), which can cause organ failure and death.

Crowd Density and Risk:

• Safe crowd density: up to 5 persons per square metre.
• Densities above 6–7 per square metre significantly increase the risk of compressive asphyxia.
• The UK’s Green Guide suggests a maximum of 4.7 persons per square metre for standing areas in public venues.

Preventive Measures:

To stay safe in crowds:

• Assess venue layout and crowd capacity.
• Be aware of weather conditions.
• Move with a partner and identify safe meeting points.
• Wear bright clothing and note all exit routes.
• Move diagonally or sideways to reach open spaces.
• Exit early if the situation feels unsafe.