Cause of Death: Boyle's Law

My quest to apply to Physician  Assistant school this year was thwarted recently when I found out that my summer Physiology was not for science majors, thus rendering it entirely useless.  Unfortunately this means that I will no longer be eligible to apply to school this year.  Every cloud has a silver lining, however!  I have an entire year to put together the most outstanding Physician Assistant application known to those admissions committees!  What better way to prove my understanding of science than by getting certified as a SCUBA diver.  Let me explain why - SCUBA stands for Self Contained Underwater Breathing Apparatus and is an underwater diving sport that involves knowledge of Chemistry, Physics and even Physiology.  I believe that my knowledge of SCUBA along with my EMT training in underwater emergencies will enable me to be a better mid-level provider in the future. 

The number 1 Rule in SCUBA is "never hold your breath." 

I know the relationship between holding your breath and being submerged in water seem quite natural, but while SCUBA diving holding your breath might actually kill you.  You might remember a rule from Chemistry called Boyle's Law - The absolute pressure and volume of a given gas are inversely proportional.  Simply put, as pressure increases, volume decreases; as pressure decreases, volume increases.  

One of the organs most affected by Boyle's law is the lung.  The lungs are the sac-like respiratory organs found in your chest cavity that are made out of thin elastic tissue.  This elastic tissue is perfectly suited to withstand the expansion and deflation that takes place during inhalation and exhalation.  This concept is complicated by pressure, however.  

So, imagine you take a deep breath and begin your descent into the ocean depths - pressure increases, causing the air in your lungs to decrease.  No problem, right?  Well, yes.  The problem lies in the ascent.  Take that same deep breath underwater, but this time start your ascent to sea level.  As you start swimming to the surface, the pressure of the water around you will decrease, thus the volume of the air in your lungs will increase.  When the volume of your lungs increases past its normal capacity, one may suffer from pulmonary pressure damage.   This damage may result in an over expansion injury, but in the worst case scenarios, your lungs might even pop like a balloon!

So, if you ever find yourself SCUBA diving, be sure to remember Boyle's Law.  I bet you never thought that those Chemistry skills might just save your life someday!