In extremely cold environments, taking deep breaths forces cold, dry air to directly assault the mucous membranes of the respiratory tract. The sudden cold stimulus causes capillaries to constrict, leading to impaired local blood circulation, frostbite, and ruptured, bleeding membranes.
Furthermore, when cold air is inhaled in large gulps, it expands inside the pulmonary alveoli, exerting significant pressure on their walls.
If this occurs frequently, the alveolar walls can become damaged and rupture.
Once an alveolus ruptures, gas can leak into the thoracic cavity, causing a pneumothorax and severely impairing normal lung function.
"Everyone stop! Are you trying to get yourselves killed? Don't take such deep breaths! I'm talking to you, the short old man. You! You're the one huffing the loudest!"
"Who are you calling a short old man?" Old Liu hated it when people made comments about his height.
