Wednesday, November 16, 2005

Recent Queries and Answers



Question re idiopathic cardiomyopathy
Do you have any thoughts on an experienced diver returning to diving after a diagnosis of idiopathic cardiomyopathy (2001). The followings meds are taken daily: Coreg & Lisinopril. The EF is 40% on a MUGA test.

Answer:
Hello:
Answers to questions are for information only, do not imply diagnosis or treatment and should always be used in conjunction with advice from your personal physician. Thank you for your interest and for taking the time to write. You will be placed on our mailing list for updates unless we hear from you otherwise.
That having been said - there are all sorts of flashing caution lights concerning this person diving.
Here is my short list of reasons why he/she should not dive:
---In idiopathic cardiomyopathy, arrhythmias are highly likely with the increased preload of immersion. This is not a good diagnosis to have and be underwater. People with this condition are prone to severe heart irregularities (dysrrhythmias) and can lose consciousness due to the irregular heart rhythm. This is exceedingly dangerous underwater and would lead to drowning in most cases. Another problem is the possibility of heart failure due to the effects of immersion. An immersed person shifts fluid centrally to the heart and lungs - leading to congestive failure in the heart that is unable to respond.
---A common cause of sudden death in athletes in cardiomyopathy is due to the severe hypertrophy of the left ventricle. This hypertrophy causes a bulge into the ventricular outflow, acting like aortic stenosis. These patients are prone to sudden ventricular fibrillation.
---Any loss of consciousness or decreased attention underwater can lead to drowning, with endangerment of the diving buddy and can cause a hazard for others on the diving trip.
---It would be good to know whether or not there has been an exercise treadmill test with results. It may be that the person has a good exercise tolerance and would not be affected by the effects of hydrostatic pressure - but this would be chancy.
I would personally be reluctant to certify this individual as 'fit to dive'.
Hope this is helpful! Let us know if there are extenuating factors. We have a son who has had a heart transplant for this condition.
Best regards:
Ernie Campbell, MD
Scubadoc's Diving Medicine Online
http://scuba-doc.com/

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Question re gastric bypass
Is there any contraindication to diving after having a gastric bypass 8 months ago? There have been no complications and I am working out without difficulty

Answer:
Hello:
Answers to questions are for information only, do not imply diagnosis or treatment and should always be used in conjunction with advice from your personal physician. Thank you for your interest and for taking the time to write. You will be placed on our mailing list for updates unless we hear from you otherwise.
There is no simple yes or no answer since there are many different kind of procedures that are performed for weight loss. Here is just a list of some of the procedures that are now being done - some with more risks than others and some with little to say for their success:

Adjustable Gastric Banding (AGB)
Vertical Banded Gastroplasty (VBG)
Roux-en-Y-Gastric Bypass (RGB)
Biliopancreatic Diversion (BPD)
Duodenal Switch (BPD/DS)
Fat Reduction - Liposuction Surgery
Jaw Wiring Surgery
Lap Band Surgery
Stomach Balloon Surgery

The type of procedure you have had performed will dictate to some degree whether or not you will be able to scuba dive. The main limiting factor would be the trapping of air in the segments of the stomach or bypassed bowel, a risk for rupture from the effects of ascent and Boyle's Law.

Diving can usually be done after operative procedures on the stomach, given complete recovery and rehab from the operation and given the ability to belch - a clue that air has not been trapped.

Liposuction would not be adverse to diving, nor would the balloon procedure (assuming that the balloon is filled with liquid).

Jaw wiring would be a distinct absolute contraindication to diving, due to the inability to manage the regulator, manage secretions and perform the clearing maneuvers required of a diver.

Hope this is helpful!
Best regards:
Ernie Campbell, MD
Scubadoc's Diving Medicine Online
http://scuba-doc.com/

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Mechanical Heart Valve
My mother has a mechanical heart valve and she was told not do dive below 60 ft. Do you have any information on this? They said it was pressure related.
Thanks

Answer:

Hello:
Answers to questions are for information only, do not imply diagnosis or treatment and should always be used in conjunction with advice from your personal physician. Thank you for your interest and for taking the time to write. You will be placed on our mailing list for updates unless we hear from you otherwise.
I am not aware of any depth effect on a person with a mechanical valve. However, there are two other big problems: the valve may not function well in high output states related to exercise; and the second consideration relates to diving while taking anti-coagulants. Diving often is associated with minor trauma (barotrauma of the ears, sinuses and lungs) and anti-coagulation can produce excessive bleeding. In addition, anticoagulation is thought to possibly worsen the damage done by a spinal decompression accident.
Patients with mechanical valves probably should not dive as both of the caveats above generally apply. An exercise stress test would be a good way to see if the valve can keep up with the increased cardiac output.
See our web site at http://www.scuba-doc.com/hrtprb.html
See Bove's web site at http://www.scubamed.com/divmed.htm
You might register and ask your question on our forum, 'Scuba Clinic' at http://scuba-doc.com/scubaclinic/ . Possibly someone else might have a different answer.

Best regards:
Ern Campbell, MD
Scubadoc's Diving Medicine
http://scuba-doc.com/


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Post pneumothorax air travel

Dear Dr Campbell
I had a bad auto accident Monday 8-29 that may have ended my almost 30 year orthopedic surgery career and 33 year scuba hobby. Grade 1=2 spleen injury, both bone forearm fracture, almost all of the left ribs fractured, along with pneumothorax. I found you on the internet several weeks ago and was impressed with your article on diving post pneumo, but have not been able to document restrictions on flying with FAA or the literature or texts on hand although my recollection is of restrictions.
So, based on that, my guess is that hurricane Katrina had less lasting memories for you than for me. I imagine that there was plenty of rain and wind, but none of the major trauma of New Orleans or the MS gulf coast. Friends and I had skirted down to the Caymans just before Katrina arrived on the eastern side of Florida. We had great diving Aug 24-26, and it was only Saturday 8-27 that the winds there whipped up the water and decreased visibility (we planned on not diving that day anyway because of flying that private-less pressurized plane back on Sunday). Florida and especially Tampa were rainy and a bit bumpy, but were a good example of how a hurricane can be avoided in an airplane.
I landed in Albuquerque that day and was driving east toward Lubbock, TX on monday when my previously undiagnosed sleep apnea got me into this abominable situation. I am still a while from deciding even if a work up for diving will be indicated if I can regain adequate strength), but with all of the holidays approaching it would be nice to travel by air again if it can be done safely. If you are able to either endorse or discredit my recollections of the warnings against air travel, it would be appreciated.

Thank you.
Sincerely,

MD

Amswer:
Hello Dr.:
Answers to questions are for information only, do not imply diagnosis or treatment and should always be used in conjunction with advice from your personal physician. Thank you for your interest and for taking the time to write. You will be placed on our mailing list for updates unless we hear from you otherwise.
I found several references to situations such as yours. Here is a section taken from The Physician and Sports Medicine:
"Air travel. Because many athletes travel great distances to compete, it is important to note some precautions concerning air travel and pneumothorax. There has been much research in the aviation literature that addresses pneumothorax and pilots, particularly in the military. However, there are no clear recommendations for airline passengers and pneumothorax, except that a patient with an acute, unresolved pneumothorax should not travel by air, if at all possible, because of the risk of enlargement of the pneumothorax that could compromise circulatory and ventilatory functions.
The issue as to how soon a pilot should return to flight after resolution of a pneumothorax remains controversial, with recommendations ranging from several months to 9 years (9,26). The authors cited suggest reasons for their recommendations that include the dramatic changes in intrathoracic pressure associated with aggressive military flying and the tremendous responsibility for in-flight safety that a pilot bears. Without these conditions, it seems reasonable that routine commercial airline passengers can return to air travel sooner. Both the athletes we describe (below) returned to air travel within 1 to 2 months without complications. Team physicians and other healthcare providers must be aware of, and appropriately counsel their patients on, the concerns of air travel and pneumothorax. "
Pneumothorax in Sports (in The Physician and Sports Medicine)http://www.physsportsmed.com/issues/2000/08_00/curtin.htm
In another article from a British travel organization, I found the following:
"You may be able to fly six weeks after surgical intervention and confirmation that the pneumothorax has resolved. If there was no surgical intervention a chest x-ray must confirm it has resolved before you can safely do so. Although recurrence is unlikely during flight, consequences can be serious and it might be better to arrange alternatives to flying up to a year after pneumothorax occurring. "(chss.org factsheet) http://snipurl.com/jn39
Finally, I found this abstract in Medline:

Am Surg. 1999 Dec;65(12):1160-4.

Air travel following traumatic pneumothorax: when is it safe?

Cheatham ML, Safcsak K.

Department of Surgical Education, Orlando Regional Healthcare System, Florida 32806, USA.

The safety of air travel for patients sustaining a recent traumatic pneumothorax has long been a subject of debate. The Aerospace Medicine Association has suggested that patients should be able to fly 2 to 3 weeks after radiographic resolution of their pneumothorax. To validate these recommendations, a prospective study was performed. Twelve consecutive patients with recent traumatic pneumothorax expressing a desire to travel by commercial airline were evaluated. Ten patients waited at least 14 days after radiographic resolution of their pneumothorax before air travel (mean, 17.5+/-4.9 days), and all were asymptomatic in-flight. One of two patients who flew earlier than 14 days developed respiratory distress in-flight, with symptoms suggestive of a recurrent pneumothorax. We conclude that commercial air travel appears to be safe 14 days following radiographic resolution of a traumatic pneumothorax.
As you can see, the wait varies from two weeks to two months to as long as one year. Sensibly, one should have proof that there is no longer a pneumothorax and that there is no air trapping - as determined by a spiral CT scan and/or helium dilution studies.
Hope this is helpful! You can also register and post your question on our forum, 'Scuba Clinic' - possibly gleaning other answers from our moderators. http://scuba-doc.com/scubaclinic/
Best regards:
Ern Campbell, MD
Scubadoc's Diving Medicine Online
http://scuba-doc.com/

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Hypertension and diving

A friend of mine has been prescribed for high blood pressure. The medication's name is LOBIVON, the chemical name is NEBIVOLOL HYDROCHLORIDE.
As is written on the information leaflet the medication is an eclectic b-blocker. According to the doctor, this medication is of a new category. Please advise us if it's safe for my friend to dive using this medication or not? Thanks in advance.

Hello :
Thanks for your query - which brings up two aspects of diving: hypertension and beta blockers. Nebivolol is one of the newer cardioselective blood pressure reducers with a second action - it increases nitric oxide in the endothelial lining of the arteries, thereby causing vasodilation. I'm unable to find any specific studies that relate to the drug and scuba diving so I'll extrapolate from my remarks on my web page.
If a patient has mild, well-controlled hypertension with none of it's complications, there is nothing to worry about if diving or planning to dive. Well-controlled hypertension means a pressure of less than 145/90 (160/95, BSAC) and complications of hypertension include renal failure, eye problems, coronary disease.
Because divers with a clear diagnosis of hypertension may have exaggerated responses to exertion, immersion and cold stresses they should not dive until their high blood pressure has been investigated and appropriately treated.
The diver who is under treatment and is controlled on medication should be allowed to dive, if there is no target organ damage (eye, kidney or heart). Of course, consideration should be given to the interaction of diving and the medication used to treat the diver. Caveats are given for the use of beta blockers and diuretics.
If one is on B-blockers--a treadmill test should be done and if one can exercise without chest pain, BP elevation, EKG changes or arrhythmias (and without fainting), then it's probable that one would be OK for sensible diving. This should be cleared with the personal physician. Beta blockers blunt the response of the body to the effects of exercise and can cause syncope in the maximally challenged diver. In healthy volunteers Nebivolol has no significant effect on maximal exercise or endurance.
Syncope (fainting) underwater could, of course, lead to drowning and would definitely not be good for the diver or his buddy. Divers who are in excellent physical condition should have few problems.
Beta blockers can also be associated with bronchial constriction, an increased risk factor with diving. This is a stated side effect of Nebivolol.
I hope this is helpful!

Best regards:
Ern Campbell, MD
Scubadoc's Diving Medicine
http://scuba-doc.com/
Thanks for your donations!
http://scuba-doc.com/donate.html
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Eustachian Dysfunction

About four years ago I under went an operation for purulent otitis media, conductive hearing loss, canal stenosis, foreign body in the middle ear and protympanum; all of which was done on the right ear. The actual operation was a tympanomastoidectomy with ossicular chain reconstruction using temporalis fascial athroplasty of incudomalleolar joint, canal plasty, removal of foreigh body in protympanum. My final audiogram and impedence test showed normal ear canal volum for both ears, negative middle ear pressure l., c/w eustachian tube dysfunction. The left ear was normal.
I am interested in taking a commercial underwaater welding course. However, I am not sure if the above procedure will keep me from doing this. Can you please tell me if this will keep me from diving? I there any kind of equipment
Answer from Allen Dekelboum, MD
Your request was referred to me for comment.

Thank you for your very complete history of your disease and surgery. If you have negative middle ear pressure in that ear with Eustachian tube obstruction, you will not be able to equalize adequately and would be a candidate for further damage to the operated ear. Without examining you, I cannot give you any advice about your entering a diving course. I would discuss this carefully with your surgeon, but from what you tell me, I think you should try a profession that would not require you to be under water, under pressure. The only suit that would keep you out of pressure would be a one atmosphere suit (JIM suit), not available except for very sophisticated research (very expensive).

Allen Dekelboum, M.D.

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