Immersion Pulmonary Edema

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Hi,

Recently a diver well known to me suffered acute pulmonary edema. There was much confusion amongst the diver's ICU physicians as to the cause, causing worry and fear with the diver and instructors.

Age over 50, did great during pool sessions for 6 weeks. In average physical shape. The first free dive was a tuck and roll to 10 feet lake water @ 75F. Second dive w/ scuba to 12 feet and acute onset cough, then short of breath and when surfaced, lost conciousness.

Oxygen was given at shoreline, gained conciousness and symptoms improved but shortness of breath persisted. Air flight to ICU - and then the confusion really started. Coronary's clean, BP fine, but persistent pulmonary edema. Aortic pump placed and removed. Eventually left hospital with full recovery.

My readings indicate that IPE can be very mild (cough) to severe, and happens in combat swimmers (young and healthy). It is probably under reported. I'll post some links later (DAN has a nice summary of IPE).

 

[Saturation]

The key to IPE is exertion in cold water, and can happen to young healthy divers. It resolves rapidly once out of water. However, what you describe is unlikely IPE but an organic heart disease.

 

[Gene_Hobbs]

DAN gave $100,000 from the research endowment to supplement a Navy grant for Dr. Moon's research into IPE mechanisms. This is a real problem for the Navy and divers/ swimmers everywhere. We are currently looking for research subjects if anyone is interested.

Our 2008 UHMS abstracts will be online in November but further reading is available from the RRR on Immersion Pulmonary Edema.

 

[headsqueeze]

Some IPE cases have been fatal, although most cases resolve on their own during observation in a hospital. A closer examination may reveal hypertension, a heart attack, cardiac valve disease or impaired contraction of the heart. (DAN)

The patient recovered during observation, cardiac cath, echo, EKG, enzymes returned normal. Of course the chest xray was abnormal w/ acute edema - the IPE was not properly diagnosed according to my information. The IPE was evaluated and treated as standard acute pulmonary edema of cardiac failure, which it was not. Intensive intervention by the book for acute pulmonary edema doesn't work as expected, and leads to confusion. IPE and acute pulmonary edema from cardiopulmonary decompensation are similar in clinical presentation. The one outstanding fact is an IPE patient is immersed in water.

 

[TSandM]

Interesting . . . reading the papers in the Rubicon archives on this issue, it appears that most patients get treated with diuresis, although the few where invasive monitoring took place had normal wedges. There is also a suggestion that lowered intraalveolar pressures due to higher inspiratory effort on a regulator may play a role in transudation of fluid. Putting all this together, I wonder if the first intervention in such patients ought to be afterload reduction and BIPAP?

 

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Basically IPE is like a shark - unpredictable. Sharks and now IPE make me think twice before entering the water. I think there are probably many subclinical IPE cases never reported. While training in cold water for free dives, I had a nagging cough --- subclinical IPE?

 

[nereas]

I take it that this malady results from underwater stress training, and therefore an unlikely affliction of normal scuba diving?

 

[TSandM]

No, nereas, it's an unpredictable phenomenon in divers and swimmers (even surface swimmers!) It seems to be more common in cold water, and in people with high blood pressure, but has occurred in situations where neither was the case. It's not particularly common, although I sort of wonder whether it may play a role in some of our deaths where they are signed out as "drowning". Could the fluid in the alveoli be IPE, and the inhaled water just come later?

 

[nereas]

Thanks, TSM!

I suppose this means that there is one more good reason to relax during diving, besides RMV control and CO2 blackout risk on deep dives.

I have never yet heard of this IPE malady. Thanks to all for the explanation.

 

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...It's not particularly common, although I sort of wonder whether it may play a role in some of our deaths where they are signed out as "drowning". Could the fluid in the alveoli be IPE, and the inhaled water just come later?

The nondiver intensivists were convinced the diver inhaled water and at one point during the hospital stay considered it a near drowning. The diver did not inhale water however.

As mentioned in Bennet and Elliott's Physiology and Medicine of Diving, I too think IPE is underreported and many are at risk.

The unpredictability of IPE makes me wonder if a 20 or 30 minute daily exercise routine designed for the risks of diving is in order. For example, a Yoga Exercise - Head Stand (Sirshasana) shunts blood to the thorax - and mimics one mechanism proposed as a cause of IPE.