CAN I DIVE WITH MY MEDICAL CONDITION?
DAN medics and researchers answer your questions about dive medicine
Q: I was diagnosed with leukaemia and underwent treatment. I am in remission and was recently cleared by my doctors for exercise without restriction. I feel well and need only scheduled followups. I have always wanted to scuba dive but am unsure given my condition and subsequent treatment. Can I dive, and are there any restrictions or precautions I should be aware of?
A: Symptoms associated with leukaemia include dizziness, fatigue, fever, weakness, weight loss, anaemia, easy bruising and bleeding, shortness of breath and infections. Clearly, these all have the potential to affect one’s well-being while diving. You and your doctor should consider two important criteria. First, diving should be considered only for patients
who are in remission – as you are.
It’s important that all divers be free from any distracting or disabling symptoms. Second, it is important that you and your physician confirm that you are not only in good health but also have good exercise tolerance. As you may know, many dive accidents result from challenges posed by the diving environment such as currents, surface swims, weather and sea conditions. All divers must be prepared to face such challenges before returning to the water.
[Dan Nord, EMT-P, CHT]
Q: I have noticed that beginning scuba divers often get nosebleeds after dives. What causes them?
A: Divers, especially new divers, sometimes report nosebleeds after diving primarily because they are unaware of the importance of equalising the sinuses and middle ears. The barotrauma that results when the sinuses are not equalised can cause blood vessels in the lining of the nose to burst. These vessels lie very close to the mucous membranes that line the nose and sinuses, and the blood can come from either of these linings. This type of barotrauma, generally the result of air being trapped within the sinuses, is not always painful, though the presence of blood can be disconcerting. With this type of injury, blood can also run down the back of the throat or pool in the sinus below the eye and emerge later. It can also act as a growth medium for bacteria and lead to sinus infections.
Individuals with a history of sinus trouble, allergies, a broken nose or a deviated septum as well as divers who currently have a cold may find equalisation difficult and may experience problems with nosebleeds. It’s always best to not dive with a cold, congestion or any other condition that might block the sinus passages.
We suggest a slow, gentle descent with frequent equalising to help decrease the risk of sinus barotrauma. Divers who are unable to equalise their sinuses or have frequent nosebleeds when scuba diving should see their personal physician or a specialist in ear, nose and throat
(ENT) care for evaluation.
[Dan Nord, EMT-P, CHT]
Q: Is there any reason cold water might increase the likelihood of lung squeeze while freediving? I have experienced lung squeeze a few times, but only in cold water. I was shallower than 30 metres. In warm water I can reach 50 metres, so I believe the squeeze is somehow related to the water temperature.
A: You described your condition as lung squeeze, but it sounds like your question is really about what might have caused you to cough up blood from your lungs (presumably) under the conditions you describe. Given the variable impact of depth on the development of the condition, you could be experiencing a form of immersion pulmonary oedema (IPE).
IPE is a multifactorial condition, largely a net effect of increased central blood volume, pressures within the chest and, for compressed-gas divers, increased breathing resistance. The squeeze is a primary component, but only part of the story. Immersion produces a shift in blood from the periphery to the core, and this effect can be magnified in cold water or partially replicated by wearing a tight wetsuit. Excessive fluid intake (hyperhydration) increases the risk.
For compressed-gas divers, respiratory loading (most important, the effort to inhale) increases with water immersion, with breathing through a mouthpiece that adds resistance (particularly as gas density increases) and with exertion. Using compressed gas or freediving, if the net effect of the various stressors is a sufficient increase in the pulmonary artery pressure, capillary stress failure can produce a shift of blood into the lungs. Symptoms of IPE can include the perception of strain or stiffness in breathing, coughing and the coughing up of small amounts of blood.
While I cannot confirm that this is what you are experiencing, it may be that the central blood volume increase magnified by the cold water is the stressor that takes you over the edge that you skirt in warmer water exposures. IPE is most likely to appear when multiple predisposing factors are acting in concert. You may have found your own threshold.
I encourage you to consult with your medical monitors, keeping in mind that the classic squeeze is not the only risk that freedivers face.
[Neal W. Pollock, PhD]
ABOVE It’s always best not to dive with any condition that might block the sinus passages
BELOW Leukaemia is a type of bone marrow cancer of malignant plasma cells, associated with bone pain, bone fractures and anaemia
ABOVE Lung squeeze is the damage or injury to the lungs due t0 increased environmental pressure on the closed gas spaces of the lungs during breath-hold diving