Respiratory Case Study 6

Decompression Illness:

 

Julie, 47, is a novice SCUBA diver, certified with 5 beach dives in Hawaii in 1999, and several subsequent boat dives. She recently went diving for the first time in 6 years while on a 6-day cruise to the Coral Sea.

 

Julie and her group encountered very rough seas on their way to a shipwreck that they planned to dive. Many passengers, including Julie, became very seasick, and most took Scopalamine as a remedy. After a poor night of sleep, and in rough seas with a strong current, Julie and her buddy descended to 26 m for 5 min, and remained at around 17m for about 20 m. She logged a total bottom time of 28 minutes. Because of the strong current, the divers used their oxygen supply more rapidly than expected, and their tanks were quite low when they ascended. The swell at the surface made it very difficult to swim back to the boat, and when she did arrive Julie was too tired to climb aboard without help. She was exhausted and collapsed in her bunk with a terrible headache and dizziness.

 

Julie was supposed to fly back to the US on the following day, but was still experiencing the headache and dizziness. She decided to visit a doctor as a precaution. The doctor tested her balance, which was poor, and tested the comparative sensation in her left and right sides, finding the right hand to be much less sensitive to a variety of stimuli. He also tested her mental abilities by timing her as she counted backwards by 7s from 100.

 

The doctor determined that Julie was suffering from decompression illness, or the “Bends,” and recommended that she be treated immediately in a hyperbaric chamber.

 

Questions:

 

1.) Describe pulmonary and systemic circulation with specific reference made to both external and internal respiratory exchange.

 

2.) How are oxygen and carbon dioxide transported in the blood? Elaborate on the role of hemoglobin in oxygen transport.

 

3.) What is the basis for decompression illness in SCUBA divers? Be sure to discuss the partial pressure of nitrogen gas in the atmosphere and why it’s only a problem for divers. What precautions do divers generally take to avoid this condition? Why are depth and duration of dives important?

 

4.) Did Julie have the usual symptoms associated with decompression illness? Explain. How does a problem with decompression account for the usual symptoms?

 

5.) Julie and her buddy did a dive that was short enough and shallow enough that according to PADI and NAUI guidelines should not have caused decompression problems. Try to explain why Julie had problems anyway (feel free to speculate…)

 

6.) What’s the difference between decompression illness and nitrogen narcosis?

 

7.) What could have happened if Julie had hopped on a plane for a long flight without being treated first?

 

8.) How is decompression illness treated? Can it cause permanent problems? If so, how?