Helium During the 1930’s the U.S. Navy tested other gases as a substitute for nitrogen. Their scientists conducted experiments using rare gases such as helium, neon, and argon. After numerous trials, helium was selected as the most suitable gas to dilute oxygen for deep diving. Helium is the second lightest element known to man; in...

As the popularity of SCUBA diving continues to grow, scientists are better able to determine what the long-term effects, if any, are on the human body. For every overt case of decompression sickness that is treated, there are many divers with covertly occurring intravascular bubbling, whose ramifications we are just beginning to understand. We know...

The effects of oxygen are increased at depth so that the maximum PO2 in diving is 1.6 ATA, and this is achieved at 218 fsw breathing air, 132 fsw breathing 32% O2, and 20 fsw breathing 100% O2. This is due to the effects of Dalton’s Law which states that on descent, the partial pressure...

POSSIBLE NEUROLOGICAL EFFECTS There is evidence of neuropathological changes in the CNS of some divers who, at the time of death, had had no recorded incidence of decompression illness and who had been considered fit to dive (Mork 1988: Movild and Mork 1994; Palmer et al 1990). There is, however, other than the acute decompression...

Diving Concerns Condition Related The pressures of diving would have no effect on the intracranial pressure. The increased intracranial pressure causes symptoms that can be confused with those of decompression sickness – headache, tinnitus, nausea and vomiting. It also causes loss of vision. Treatment Related Treatment is by osmotic diuresis, diuretics, spinal taps and the...

Diving Concerns —Condition RelatedRecurrence of condition is about 2 % in adults. Seizure activity would be a major concern, as drowning would surely ensue if this occurred underwater. Oxygen toxicity would increase this risk. —Treatment RelatedScarring from the treatment is said to produce an increased risk for the development of bubbles in areas of altered...

TIA’s are episodes of decreased or lost consciousness due to decreased blood flow to a portion of the brain. Occurring underwater they can lead to drowning and/or arterial gas embolism.Transient Ischemic Attacks are included in the list of 'Neurological Absolute Contraindications’. These include: History of Seizure disorderLoss or change in the level of consciousness underwater...

Noncommunicating syringomyelia occurs as a complication of trauma, meningitis, hemorrhage or tumor, the cyst or syrinx developing in a segment of the spinal cord damaged by one or more of these conditions. I can find no reports that damage from a decompression accident has been related as a cause. This condition is not mentioned in...

If you are considering taking up diving and have a spina bifida congenital defect, unless you are learning in a specialized program you are taking a great risk. There are certain things that need to be addressed before any decision can be made, such as: 1. The extent of usage of your lower extremities; how...

Narcolepsy is a chronic disorder affecting the brain where regulation of sleep and wakefulness take place. Narcolepsy can be thought of as an intrusion of dreaming sleep (REM) into the waking state. The question of the narcoleptic becoming certified for scuba diving is posed periodically – usually followed by a barrage of letters and postings...

One cannot paint Parkinson’s Disease with a broad brush and say that people with this condition should not dive. In some cases, the body is affected very little by the disease in it’s early stages and a person should not be deprived of this pleasure. Of course, there are those in the later stages of...

What is Multiple Sclerosis? MS is thought to be an autoimmune disease that affects the central nervous system (CNS). The CNS consists of the brain, spinal cord, and the optic nerves. Surrounding and protecting the nerve fibers of the CNS is a fatty tissue called myelin, which helps nerve fibers conduct electrical impulses.In MS, myelin...

Diving with hydrocephalus can be accomplished if several aspects of the problem are taken into account: 1. The extent of neurological disability; how much numbness of your extremities and whether or not there is any „autonomic” instability. This means things like postural hypotension, blood pressure changes and ability to react to cold water immersion. 2...

As far as diving with migraine is concerned–there is mixed opinion as to the proper thing to do. Some think it to be an absolute contraindication to diving, others think it to not be a significant problem. The migraine following a dive might be difficult to distinguish from decompression sickness and can possibly be provoked...

Headaches at Depth CO2 Retention Due to skip breathing, gear malfunction, rebreather failure. Causes a „sick headache” type of generalized pain and can be associated with nausea and vomiting. The tendency to retain CO2 may be suspected in divers who frequently experience post-dive headaches or pride themselves on low air-use rates. Tempero-mandibular joint syndrome Caused...

Scuba Diving Concerns: This condition has skeletal muscle weakness which can involve extremity, truncal or bulbar groups and typically evolves over a matter of several hours to a few days can affect diving and boat crew abilities creating safety in the water as well as buddy rescue concerns. In the C. Miller-Fisher variant, ataxia as...

Any form of unconsciousness under water is deadly, with the attendant likelihood of arterial gas embolism and drowning. Epilepsy, even if well-controlled, places you at great risk and one should not even consider the possibility of diving. Some years ago I worked with Dr. Jeff Davis in writing „The Medical Examination of Sport Scuba Divers,”...