<span>The mineral crystals in obsidian are too small to see without a microscope. This is because the rock cools so rapidly from magma that crystals barely have time to form. Obsidian is a normally happening volcanic glass framed as an extrusive molten shake. It is delivered when felsic magma expelled from a well of lava cools quickly with negligible precious stone development.</span>
The answer is Aspiration pneumonia. The low pressure in the cuff of the endotracheal tube is a risk for the aspiration pneumonia while the high cuff pressure can cause ischemia, pressure necrosis and tracheal bleeding.Hope this would be of big help.