This document summarizes several respiratory disorders: Bronchial asthma causes difficult breathing and wheezing due to bronchiolar constriction from smooth muscle contraction in the bronchioles. Common symptoms include shortness of breath, chest tightness, and wheezing. Mountain sickness occurs in people going to high altitude for the first time, developing symptoms like nausea, vomiting, increased heart rate, headache, fatigue and lack of sleep within a day before acclimating. Decompression sickness occurs when a person returns rapidly from a high atmospheric pressure environment like deep sea diving to normal pressure. Symptoms include severe joint pain, numbness, temporary paralysis and muscle cramps.