Why Divers Die 

On occasion we choose to report on diver's deaths. Because we're a newsletter for serious divers, we feel it's in our subscribers' best interest to publicize case studies of dive deaths periodically so that we can all avoid repeating the errors that were made.

There were only 85 dive deaths in 1996, down from the previous year and down significantly from highs during the mid-1970s. Most cases cited in this article come from the 1995- 96 Diver's Alert Network case studies, with cases from other nations added occasionally. All editing and commentary are solely ours.

Last month we discussed deaths from entrapment and entanglement, both major causes of dive deaths. But many dive deaths are caused by the diver's preexisting health problems which have been aggravated by the physical demands of the dive.

Not that tropical diving necessarily seems demanding.... You get a ride to your boat, have someone help you with your tank, fall over the edge of the boat, tour the Cayman Wall, have your tank lifted up before you climb back on the boat, and go home. It certainly doesn't require a diver to be fit, that's for sure. Probably because diving is so user-friendly, cardiovascular disease is a major cause of diving death.

But diving causes exertion. And as it's written in the 1997 DAN fatality report, "exertion increases the cardiac output and the need for oxygen by the heart muscle. If the vessels supplying blood, and ultimately oxygen, to the heart are narrowed by atherosclerosis, the result can be death of the tissue, and, potentially, a short circuit in the electrical conduction of the heartbeat."

These are a few cases from the DAN file where cardiovascular disease, often unknown, played a role in a diver's death.

A very experienced, 56-yearold male dive instructor made a dive to 75 feet for 40 minutes with a buddy, then surfaced and began to swim back to the boat. During the swim, the divers became separated, and the decedent was found floating near the stern in full cardiopulmonary arrest. . . . But had the diver paid attention to his own body, he might be alive today: he had experienced an episode of fibrillation -- irregular heartbeat -- a week earlier, and the autopsy later revealed extensive cardiovascular disease.

A 40-year-old female with fewer than 20 lifetime dives made a 66-foot dive for 20 minutes. She was low on air and surfaced, then began to struggle and complained of having difficulty breathing. The other divers came to her aid, but she was unresponsive. The autopsy revealed extensive hardening of the heart tissue.

Shortness of breath? Fatigue? Listen to your body.

A very experienced, 51-yearold male dived while his wife waited in the boat. He had a history of hypertension. After diving in a strong current, he came alongside the boat and told his wife that he was having difficulty breathing and was very fatigued. She attempted to get a rope to him, but he quickly sank beneath the surface. The body was recovered one week later; an autopsy showed severe coronary artery disease.

Heart problem aren't restricted to older divers. A 27-yearold obese male had 15 lifetime dives, but hadn't made a dive in nearly two years. He and three friends made a 30-minute, 30-foot shore entry dive. He then complained of heartburn and fatigue. Still, he made a second dive, during which he became separated from the other divers, called for help on the surface, and then lost consciousness. Resuscitation efforts were unsuccessful.... Had he listened to his symptoms and refrained from diving, would he be alive today?

As DAN notes, cardiovascular disease can be clinically silent, and the first symptom may be sudden cardiac death. As a potentially strenuous activity, diving requires an adequate level of physical and cardiovascular fitness. An intelligent diver will follow a healthy diet, regularly engage in aerobic exercise, and obtain periodic medical evaluations. Older individuals should have a thorough physical examination with appropriate assessment of their cardiovascular status. An electrocardiogram and exercise treadmill test should be strongly encouraged.

While DCS is the most common crippling accident that happens to divers, it's usually not a killer----unless, of course, you do something really stupid. A 32-year-old, moderatelyexperienced diver made a dive to 276 feet on air to explore a wreck. His regulator was freeflowing, which caused him to run out of air before any decompression obligation could be met. He went directly to the surface after a 14-minute bottom time, and he immediately radioed for help but then became paralyzed and lost consciousness. He spent several days in a hyperbaric chamber before developing pulmonary complications and dying three weeks later.

Embolism, however, does claim many divers, at least seven in 1996. This 38-year-old novice made a shore entry into a rip current and spent only five minutes at 10 feet before becoming anxious and surfacing. He became unconscious and was helped to shore by his dive buddies. Cardiopulmonary resuscitation was unsuccessful.

Such a case brings to mind the upwellings one can find in serious current diving, even in Cozumel. If the current pulls you up, don't hold your breath out of surprise. Here is evidence that ten feet is enough to kill you.

Another case shows precisely why a tropical diver who decides to try a cold water wetsuit dive had damn well better get training. This 54-year-old female certified diver with approximately 60 lifetime dives was using a drysuit with which she had no experience. During the second dive, she had significant buoyancy problems, inverted her body, then made an ascent to the surface where she struggled and would not accept assistance. She lost consciousness. Resuscitation couldn't revive her.

In 1995, a 52-year-old experienced male diver was making a deep dive using trimix (oxygen, nitrogen, helium). He had a problem with his drysuit before the dive so he shut off the automatic dump. During descent, his buddies stopped at 250 feet, but he continued down to 307 feet. Witnesses saw him pop to the surface and resubmerge as his buddies made their decompression stops. His body was recovered an hour later.

And there is always someone trained as an open water diver who thinks he's capable of taking anyone diving. Here, a guy took his 32-year-old uncertified girlfriend diving to 60 feet. He had equipment problems and became separated from his girlfriend, who he found on the surface 25 minutes later without her equipment. She died two days later, apparently from an embolism. An examination of the equipment revealed a malfunctioning and incorrectly-rigged buoyancy compensator and a tank that was out of certification.

Next issue: more cases