When cold, or cold for long periods can lead to hypothermia consciousness disorders, convulsions, coma and even death. Upper respiratory tract infections such as the nose, throat, sinuses, ear infections; lower respiratory tract infections such as bronchitis, acute exacerbation of chronic obstructive pulmonary disease due to bronchial infections, pneumonia is a very common disease when cold weather.
1. Physiological basis
- Normal human body temperature is maintained between 37 ° C to stabilize the balance between the heat and heat loss through the environment. when the body is exposed to cold environment will respond by increasing metabolic heat production to maintain body temperature. In addition, the body reacts in contraction of blood vessels under the skin of peripheral blood supply in order to reduce to the skin, helps the body retain heat. In normal individuals, the blood vessel that feeds the organs will stretch further to regulate the excess amount of blood under the skin due to vasoconstriction.
- When you breathe, air is upper respiratory mucosal lining of the nose-throat as heating warm, moisten and cleanse the part before going into the trachea. On the surface of the bronchial mucosa has cells excrete mucus and epithelial cell layer with tiny cilia (villi) on the surface. Mucus layer adhesion molecules of dust, bacteria, viruses present in the inhaled air. In the mucus layer has some protective factors such as antibodies that inhibit the activity of viruses, bacteria. The villi surface motion bronchial mucus layer in the direction pushed from the small airways inside the large bronchi outside and has since been coughing up or we automatically swallowed gastrointestinal during sleep. At the bottom of the lining of the bronchial and alveolar walls there are macrophages, white blood cells help protect the body against pathogens such as viruses, bacteria.
- When the weather is too cold, lining the road upper respiratory not enough for heating the air flow as usual, the air inhaled into the respiratory tract caused low temperature condition of blood vessels shrink the lining of the respiratory tract. Factors cold and contraction of blood vessels that make the cilia on the surface of the bronchial mucosa poorly, lack of protective cells are present in the respiratory tract. When the body gets cold, the first parts affected are the upper respiratory tract caused rhinitis, throat, sinuses, from which infection may spread to the middle ear inflammation, bronchial and spread to the lung parenchyma cause bronchitis, pneumonia. However, there are also always cases of pneumonia with no expression on respiratory infections significantly.
- For the respiratory system from the nose and throat to the agency bronchopulmonary direct contact with cold air over an area wide area to almost 100 m2 to respiratory organs are most affected with cold air. In young children, due to low body weight, the ability to generate heat to maintain body temperature also limits should be as vulnerable to the complications caused by cold.
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