SCUBA DIVING
FITNESS TO DIVE
SCUBA
(Self Contained Underwater Breathing Apparatus) diving is a safe sport enjoyed by millions with a fatality rate less than downhill skiing (estimated at 1 in 95000 dives.) The risks of serious injuries are either from breathing compressed air or by the other environmental factors exists.

Scuba diving requires that the participant be healthy and be able to respond to problems under water. In the same way that an individual should be competent to drive a car, divers should be held to a higher level of competence since problems could endanger not only themselves but also other divers and rescue workers.

Where Not to Dive
Absolute conditions are those diseases or injuries where a person should not dive under any circumstances. These may be temporary as some conditions will change but are often permanent. An individual who was previously cleared to dive may acquire a condition temporary or permanent that would disqualify them from diving. It is every divers responsibility to disclose any conditions that may make him or her endangered, as well as anyone attempting to rescue them. Relative contradictions are conditions that may or may not prevent someone from diving, depending on an individual review by a physician who has knowledge in scuba.


Prevention
Proper scuba technique and medical screening may help minimize these hazards. Scuba diving should be learned from a properly organized course, and not in a compressed afternoon.
Panic has also been a major determinant for disaster in diving. Experience and training will help minimize this. Avoid diving partners who are immature, intoxicated or using street drugs. If you don't like your diving partner(s), break up with them before you agree to go in the water, otherwise, stick with them until the dive is over.

Illness
Any illness should be cleared with a dive physician or by checking with the Divers Alert Network (D.A.N). If in doubt, don't dive. No matter how expensive the trip was, remember you always can enjoy a snorkel, which does not have the risk of dysbarism, since you are not breathing compressed air.
Divers can be affected in many ways by dive related diseases, as well as the mundane types. It is often difficult for even experienced physicians to make a correct diagnosis in an ill diver.


Conditions That May Prevent People From Diving
Because of the varied severity of many conditions, this list is deliberately vague and incomplete and persons with specific medical problems should always clear them with a dive physician.
People generally do diving over 16 years of age, but frequently children wish to dive. Children as young as 12 years may be considered for diving but this should be very carefully thought out.

Cardiac - Any serious cardiac conditions should not dive unless screened by a Cardiologist and are able to perform 13 METS on an exercise treadmill.

Pulmonary
- Any asthma or lung disease should be assessed by a Respirologist, chest x-rays, spirometry and possibly exercise challenge may be needed.

Neurological - Patients with alterations in consciousness or uncontrolled seizures should not dive. Prior decompression illness should be carefully reviewed to evaluate if they should ever dive again.

Ear/Nose/Throat - Divers with hearing in 1 ear or prior ear surgery should not dive. Sudden ear or sinus infections should also not dive till conditions improved (there is a risk of accident and they will have a painful dive anyways).

Gastrointestinal - Divers with digestive diseases have had increased incidences of injuries. Diseases should be stabilized before diving is allowed.

Diabetes - Diabetics with poor control or end organ damage are not recommended to dive. Other endocrine problems should be well controlled. Extreme obesity has had a higher incidence of decompression illness.

Pregnancy - Women who are or many become pregnant (during dive trip) should not dive. The fetus is vulnerable to dive injuries and the hyperbaric chamber as well.

Blood diseases - Severe anemia and sickle cell diseases should not dive.

Orthopedic - People with severe back pain or recent fractures should not dive. Prior aseptic necrosis (a disease seen in commercial divers) should stop diving.

Behavior - Any psychiatric condition that limits an individual's ability to cooperate with others, solve problems, or react to stress should not dive. Divers themselves should screen unknown diving buddies for incompatibilities before the dive begins. There should be no use of street drugs or alcohol with diving.

Dental - All cavities and closed spaces should be managed prior to diving.

Drugs - People on medications that interfere with thinking, concentration, or cause sedation should not dive.

Any other condition not mentioned above, that may interfere with the thinking or performance, may also limit diving.
Consider not diving if you are unwell. Definitely do not dive with an ear or sinus infection or any type of respiratory wheeze. One of the main concerns about diving injuries is that many divers will minimize their symptoms or deny them. It is important to have a plan if something goes wrong, agree with your diving partner(s), and always follow through.


Pre-Diving Planning
In addition to proper certification, divers should be up to date in their vaccinations if traveling, be counseled on malaria and traveler's diarrhea prevention, be knowledgeable in the prevention of parasites (from swimming in infected water), and seafood poisoning. Divers should be knowledgeable in the conditions where they are diving as well.


Some Conditions Related to Breathing Pressurized Gas
Nitrogen Narcoses
(Rapture of the Deep) This usually occurs at depths of 30 feet or 40 meters and is similar to feeling intoxicated. This may be hard to recognize in beginners, so they should limit their depths when starting. Symptoms may range from poor judgment, over confidence, inappropriate behavior and even stupor or coma. The treatment is ascension, until symptoms clear.

Central nervous system oxygen toxicity occurs when breathing mixed gas combinations (not regular air) at greater depths. Symptoms include; nausea, dizziness, ringing ears, altered vision, and even convulsion. If convulsing at depths, the buddy should either reduce the oxygen partial pressure by switching tanks or by gentle ascension will also decrease the oxygen pressure, but managing an underwater seizure is difficult.

If warning symptoms occur, the diver should alert his buddy and make a controlled ascent. If a seizure starts, the buddy should:

a) Get behind the diver and release the buddy's weight belt (if victims wearing dry suit leave on as this affects the balance).

b) Leave the regulator in the victim's mouth. If it is out, do not replace it.

c)
Grasp the victim around the chest, above the underwater breathing apparatus. If difficult, use the best possible method to gain control.

d)
Make controlled ascent to surface, while keeping slight pressure on victim's chest to help exhalation.

e)
If additional buoyancy activates victim's life jacket, do not drop your own weight belt or use your own life jacket.

f)
Inflate the victim's life jacket at the surface if it has not done so.

g)
Remove the victim's mouthpiece and switch valve to SURFACE (for rebreather masks, as this could flood the unit and weigh the victim down).

h)
Signal for help.

i) Once the convulsions are over, open victim's airway by lifting head back.

j) Mouth to mouth breathing if necessary.

k) Transfer victim to dive medicine facility.

Reference: U.S Navy Dive Manual Volume 2 Revised


Carbon Dioxide Toxicity
This can happen under heavy exertion, by skip breathing (slow breathing), or equipment failure. Symptoms include shortness of breath, headache, nausea, dizziness, and confusion. Divers may develop rapid breathing, muscle twitches, and unconsciousness. If breathlessness occurs, divers should stop and rest until breathing returns to normal, if not, then ascend.
Lung Overpressure Syndrome

These problems can occur independently or with an air embolism. They all represent that the lung is injured and an embolism should be suspected.
Pneumothorax usually is felt as chest pain or shortness of breath and occurs when air enters the space between the lung and chest wall. This problem can worsen with time and treatment in a hospital to remove this is needed.

Mediastinal Emphysema is when air becomes trapped in the space between the heart and the lungs, and is felt as chest pain, shortness of breath and faintness. This must also be followed in a hospital.

Subcutaneus Emphysema is when escaped air from the lungs is trapped under the skin, usually at the neck. A swelling and crackling is felt at the neck, with a change of voice and difficulty swallowing. This is a simple condition and no treatment is required for it alone. Breathing 100% oxygen will help resolve all types of over- pressure problems.

Motion Sickness should be anticipated and medication should be used with caution since they all cause some drowsiness. It is advisable to cancel a dive if sickness is severe. Some will take meclizine 25 mg taken 2 hrs before dive (lasts 6-12h).
Some illnesses require recompression therapy. They can be subtle but should be acted on promptly if suspected.

DECOMPRESSION ILLNESS - is the broad term to describe both air gas embolism (AGE) and decompression syndrome (caused by nitrogen bubbles forming in the body) signs and symptoms of AGE include - any type of neurological problem, chest pain, personality change, bloody froth, paralysis, convulsions, and death. Symptoms can occur immediately after surfacing. Airplane travel can also precipitate nitrogen bubble formation. DAN recommends not to fly 12 hours after the last non- stop diver. The U.S Air Force recommends 24hrs. Longer time is needed if the dive is a complicated one.

Decompression illness symptoms may also include fatigue, itch, pains in muscles or joints, and a blotchy rash. Even muscular symptoms are worrisome since bubbles could soon form in the nervous tissue. Once you suspect Decompression illness the diver may be categorized as Emergent, Urgent, and Timely.

Emergant
cases are obviously very sick. Begin CPR, and arrange evacuation. Check for foreign bodies and place patient on back (if vomiting, turn onto side) 100% oxygen should be supplied.

IV fluids using isotonic fluids without glucose should be given (this corrects dehydration and reduces hemoconcentration) Give 1litre over 30 minutes then 100-175 cc/hr.

If trained, insert urine catheter to monitor urine output. After stabilization, contact D.A.N for nearest chamber location. Transfer even if the victim is improving. Take a detailed history, and evaluate neurological status. If flying, pressurized aircraft is recommended.

In cerebral arterial gas embolisms, having the head slightly down, theoretically reduces further emboli towards the brain. Some believe that this can also increase cerebral pressure. A compromise is to keep the victim level with the body and tilted to the left side. In Decompression sickness, muscular or other body movements can dislodge venous emboli so patients should rest. Near-drowning victims movements may redistribute fluid causing decreased lung compliance. Patients with hypothermia should not be jostled as this could precipitate a cardiac arrhythmia a in a chilled heart.

Additional treatments that have some evidence to support them, include giving ASA (chewable baby aspirin may stops platelets accumulate around bubbles and lidocaine (dose is the same as for cardiac patients). Given in 1 or 2 boluses, Lidocaine acts to increase cerebral blood flow and may prevent leukocyte activation. Corticosteroids like decadron are sometimes also given but there is less evidence of their usefulness.

Urgent - These patients are those with severe pain that has unchanged or become worse over hours. Their neurologic status appears normal. They should be placed on 100% oxygen and given oral fluids. Contact DAN and arrange a transfer.

Timely - These patients have vague complaints with abnormal sensations. Phone DAN and go to the nearest medical facility.


Dive History
This information is very helpful to D.A.N. Find out all dives (dive logs), symptoms (onset and progressive), all first aid measures, description of rashes, and any other medical information.
Neurologic history of injured divers should include:

1) Orientation (to name, place, and time)
2) Check movement of eye following a finger, check pupil size and vision
3) Look for symmetry of facial muscles, facial sensation
4) Hearing (check ability to hear rustled hair at each ear)
5) Watch the swallowing reflex 6) Check if tongue is straight when stuck out
7) Check muscle strength - ask patient to shrug shoulders against resistance, check the strength of both arms and legs by asking the patient to bend and extend while you resist movement. Look for symmetry in all findings.
8) Check sensory perception to light touch along left and right side of body.
9) Balance and coordinate. Have divers walk heel to toe in a straight line if able, forward and backward. Then stand with feet together, eyes closed and palms held straight out. Check for ability to maintain balance and be prepared to catch the person. Check the divers ability to touch your finger and their own nose while you move your hand.

Suggested Divers First Aid Kit (Basic)
  1)
Vial of rubbing alcohol (to neutralize jelly fish stings)
  2) Package of baking soda
  3) Decadron 8mg or Prednisone 50mg (for anaphylaxis)
  4) Motion sickness tablets (meclizine, phenergan, gravol, ginger)
  5) Epipen
  6) Mechanical suction device
  7) Resusitube (combi-tube) with training
  8) Tourniquet (stop bleeding)
  9)
Water-proof bandages
10) Rubber cement (to pull out spines, envenomations)
11) Oxygen and training
12) First aid training
13) Pressure bandage to slow venom from sea snakes and blue octopus bites
14) Brain

By doing these tests early and regularly at 30-60 min intervals, valuable information about a neurologic injury is obtained while awaiting evacuation. (Tests 1,7, and 9 are the most important)


Other Problems
Sinus Squeeze -occurs as acute pain in sinuses
Mask Squeeze- painful pressure buildup around mask
Ear Barotrauma- Otitis media barotraumas acute pain in ear. Should not dive till healed. Inner ear disturbance should be treated as a possible urgent referral to D.A.N (it might only be a perilymph problem in the inner ear but it cannot easily be differentiated from AGE or DCI
Marine animals and envenomations are beyond the scope of this pamphlet but should be treated by experienced people.




Underwater Oxygen Therapy - Method of recompressing when Hyperbaric chamber is >12hours away. Use only if pre planned and experienced personnel. Pioneered in Australia.

References:
1) Dive and Marine Medicine (3rd Conference. March 2000, sponsored by The Undersea and Hyperbaric Medical Society.
2) Dive and Travel Medical Guide Ed Thalmann, Editor, Revised 1999, published by D.A.N.
3) Divers Alert Network (D.A.N.) is a non-profit organization that gives information and advice to the general public. They support diving research and have a 24-hour emergency phone number (1-919-684-2948) for dive accidents. Members are eligible for very good travel insurance packages while on dive-related vacations.
4) Bore, Alfred A and Davis, Jefferson C. (1990) Pub W.B Saunders. Diving Medicine.
5) Edmonts (1978) Diving and Sub Aquatic Medicine 2nd Edition. 6) Divers Alert Network. Report on Decompression Illness and Diving Fatalities 2000 Edition.
7) Undersea and Hyperbaric Medical Society Inc. (July 21, 1995) Published meeting. Are Asthmatics Fit to Dive?
8) Rose, S (2001) International Travel Health Guide 12th Edition
9) Divers Alert Magazine Published by D.A.N.
10) D.A.N Website link: http://www.diversalertnetwork.org/

For your convenience we have prepared downloadable pamphlets on:
Fitness to Dive
Front Page - Back Page
Scuba First Aid
Front Page - Back Page

Scuba Medical Assessments
We assess prospective scuba diving candidates to determine if they have any medical conditions that prohibit them from diving. The charge for signing a clearance form is $50.00. Divers who develop problems and need to be assessed are covered by Manitoba health as insured services and there is no charge for these assessments. We encourage all SCUBA participants to check with us if they feel they have a problem that will affect them while diving. For more information on diving medicine please follow this link. Any diver with an acute problem suggestive of a serious dive accident must attend the nearest emergency centre for immediate treatment. Our clinic is listed as a resource through the divers alert network and can be consulted with for dive injuries, but acute cases must always go through the emergency department.

Divers Alert Network (DAN at www.diversalertnetwork.com) is an excellent resource for divers with pre-existing medical problems as well as for those with suspected Dive injuries. They have a good travel insurance plan for divers and also provide phone assistance for divers.

Canadian Amphibious Search Team (CAST) Our clinic provides the medical review for members of CAST. CAST is a professional search and recovery unit dedicated to assisting individuals, justice departments and government agencies worldwide. CAST is comprised of over fifty professional men and women from various emergency service backgrounds, including forensic investigators, coroners and underwater investigators. The scope of their mission is not limited to evidence and body recovery, be it on a small or large scale. CAST is also a training agency offering specialized courses in Capsized Vessel Rescue, Swift Water Diving, and K9 Handling (specializing in cadaver).
If you require the services of CAST please contact them directly, http://www.casteam.org

Winnipeg Scuba Resources
We are involved with the local Scuba diving community. Besides being medically fit to dive it is even more important that new scuba divers receive the proper instruction in technique and equipment and we stress that travelers should be properly instructed. These resources are available in Winnipeg at several Dive shops. They will train and educate divers even in the winter. Through organizations such as PADI (Professional Association of Divers International), arrangements can be made so that once a candidate has taken their written exam and pool work they may do their open dive certification on vacation also through PADI. This arrangement ensures that they get full instruction. Our clinic has seen several divers who have had decompression illness from being improperly trained abroad.

Underwater Investigation
We are also pleased to announce that our Travel Clinic Nurse, Gail, has successfully completed the Underwater Investigator course and is now qualified as a consultant to underwater forensic investigations.

Guidelines for Physicians in Scuba Medicine
Dr Podolsky was part of the College of Physicians and Surgeons Committee to review the Recommendations for physicians examining recreational scuba divers. Unfortunately funding for all of the colleges guideline programs was cancelled because of limited funding by Manitoba Health. It is our plan to attempt to finish the guidelines independently as a volunteer committee (without any official validation or recognition by the College). Interested members of the Manitoba Physician and Scuba community may contact us if they wish to be involved with this endeavour.

Aviation Medicine
Our clinic is familiar with Aviation medicine but at this time we are not able to certify aircrew. Dr Podolsky has worked for the Canadian Air force as a civilian physician but is not licensed to unground pilots. He can give an opinion but Pilots and Aircrew seeking to be ungrounded must see a designated Health Canada Physician for this.
Our clinic sees many people with anxieties and questions about flying. There are also several medical conditions that may limit a person from flying. In order to evaluate these we need to see each patient in person by appointment before making any recommendations.
We will try to assess patients with urgent needs (i.e. a possible ear infection) prior to their departure.


Manitoba Underwater Council - A community for SCUBA divers.