Mr. Alvarez bumped a bee’s nest while making repairs on his roof. Not surprisingly, he was promptly stung several times. Because he knew he was allergic to bee stings, he rushed to the hospital. While...

Mr. Alvarez bumped a bee’s nest while making repairs on his roof. Not surprisingly, he was promptly stung several times. Because he knew he was allergic to bee stings, he rushed to the hospital. While waiting, he went into a state of shock and had extreme difficulty breathing. Examination showed his larynx to be edematous, and a tracheostomy was performed. Why is edema of the larynx likely to obstruct the airway? What is a tracheostomy, and what purpose does it serve?