Scuba Diving club,
Southern California
Sea Sabres
Pulmonary
Edema of Diving
What is pulmonary edema?
Pulmonary
edema is the sudden filling of the lungs with fluid, generally thought of as
being caused by a failure of the left side of the heart to pump properly.
What is the cause?
Pulmonary
edema, characterized by cough, shortness of breath, and hemoptysis, has
been observed in both divers and surface swimmers. This is a relatively
rare condition whose etiology is uncertain, but would appear to be related to
immersion. Divers may dive for many years before first experiencing symptoms;
thereafter, they may experience recurring episodes interspersed with periods of
normal diving.
Characterization of
an attack!
Symptoms
may begin on the bottom, during ascent, or shortly after ascent -chest
pain being notable in it's absence, which helps to eliminate chokes as a
diagnostic possibility. Chest examination reveals rales, and chest
radiographs show the classic pattern of pulmonary edema. Significant
decrease in arterial O2 may be present. Symptoms and signs usually
resolve spontaneously over 24 hours.
Precipitating causes
Episodes
appear to be precipitated by factors that increase cardiac preload and
afterload, including immersion in water (particularly cold water), heavy
exercise, negative pressure breathing, and predive fluid overload.
What To Do
Get
the diver out of the water
Elevate the head in the sitting position
Provide 100 % oxygen, mask if possible
Rotate tourniquets, if a qualified person is
available.
Get the diver to an emergency facility as soon
as possible.
Return to diving?
If
a medical workup fails to reveal any intrinsic heart or lung disease - the
problem may not reoccur with future diving. Examine the risk factors noted
above and act accordingly.
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Breathing Difficulty |
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By Fred Bove, M.D., Ph.D. |
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For the past 10 years or so we have been aware of an interesting and worrisome
problem that occurs in some divers while they are underwater. The problem is
the rapid development of severe shortness of breath caused by fluid leaking
from the bloodstream into the air spaces in the lungs, and impairing the flow
of oxygen into the blood. In medicine we call this pulmonary edema. It is
somewhat akin to drowning, but the fluid comes from the body and not from the
outside environment. A letter from a diver describes the sensation:
I went down to the bottom, knelt in the sand and remained still so as
not to disturb the fish. I was in about 25 to 30 feet of water for about 10
minutes or so when I started coughing into my regulator. I noticed my
breathing was a little fast for someone who was inactive. Over the next five
minutes or so, my coughing became more and more frequent. I started to become
a little concerned and signaled to my buddy that I was going up. By the time
I surfaced I was very short of breath. I swam to the stern of the boat and
just hung on to the ladder. I kept coughing and coughing and coughing.
I
kept coughing up a lot of secretions. I was having coughing fits. By the time
we got back to the dock, my coughing slowed up. The shortness of breath
cleared up after I was inactive and sitting for a few minutes. It was about
five or six hours before I felt totally normal. If I had to put a label on
what I was experiencing, it would be that of pulmonary edema. This episode
was the third and worst yet
. This problem was described in 1990 at a scientific meeting of diving
medical physicians. The syndrome occurred in divers who were wearing wetsuits
in cold water. In the first report they were all over 50 years old, and it
was thought that these individuals had heart problems that occurred for the
first time while diving. However, subsequent reports were published that
included younger divers in warm water with no medical history of any serious
disease. Some of these individuals were taken to hospitals and were found to
have fluid scattered throughout the air spaces of the lungs and inadequate
oxygen in the blood. This problem, called pulmonary edema, usually occurs because the heart is
injured or damaged, or because a process has occurred in the lung to allow
fluid to leak from the bloodstream and fill the air spaces with plasma. The
most serious and discomforting symptom is the rapid onset of severe shortness
of breath and coughing while diving. The diver describes this well in the
letter, which is a typical description. Although immersion pulmonary edema is rare, it is certainly not trivial
and can cause significant problems with divers. The mechanism for it is not
well-understood, but some precautions are worth stating: Be sure your regulator is breathing normally. If there is resistance to
inspiration, have the regulator checked and adjusted. A malfunctioning
regulator that does not supply adequate air will cause negative pressure
breathing and may induce pulmonary edema. Although the cause for immersion pulmonary edema is unknown, these
precautions can provide some protection. If you develop severe shortness of
breath underwater, ascend at a normal rate to avoid lung overpressure. If
your symptoms persist on the surface, breathe 100 percent oxygen if it is
available. Consult your physician to be certain that your health is normal
before returning to diving. You can find more information on |
Posted June 23, 2003