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Buzzacott P, Denoble PJ, editors. DAN Annual Diving Report 2018 Edition: A Report on 2016 Diving Fatalities, Injuries, and Incidents [Internet]. Durham (NC): Divers Alert Network; 2018.

Cover of DAN Annual Diving Report 2018 Edition

DAN Annual Diving Report 2018 Edition: A Report on 2016 Diving Fatalities, Injuries, and Incidents [Internet].

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The 2018 Annual Diving Report presents an analysis of recreational diving fatalities that occured in the US or Canada or that involved US or Canadian residents. While the recent years have seen a decline in the number of fatalities, we are saddened to report that 2016 saw an above-average number of recreational diving fatalities. Many of the circumstances and risks associated with these fatalities could have been avoided, or at least reduced. By describing what is known about diving fatalities each year, DAN hopes that every diver will consider their diving decisions carefully and will take greater care in the water. Our sport is relatively safe when undertaken responsibly, but we can do more, and we must, if we are to strive for all dives to be injury- and fatality-free. (Note that fatalities associated with scuba diving are covered in Section 1 of this report, and that injuries and fatalities associated with breath-hold diving are covered in Section 4.)


The data collection process at DAN begins when a diving death is identified through internet alerts, news stories, forums, or reports from affiliated organizations, such as county coroners, fish and wildlife officers, county medical examiners, local law enforcement agencies, or members of the public. Each death is classified as to whether it should be followed up on or not. All recreational diving fatalities that occur in the US or Canada are tagged as follow-up cases, and all deaths of US or Canadian citizens, no matter where they occur, are also marked for follow-up. Any fatalities that occur outside the US or Canada and that involve citizens of other countries, as well as any fatalities that occur during non-recreational dives (e.g., military dives) are classed as no-follow-up.

Online news media outlets are monitored for keywords involving diving and scuba deaths. Other sources for notifications regarding fatalities include families of DAN members and friends and acquaintances of decedents who are aware of DAN’s fatality data collection efforts. The DAN Medical Services Call Center (MSCC) is also a valuable resource, since the DAN Medical Services Department assists with the management of any diving incident that is called in, whether the victim is a DAN member or not.


Diving-related deaths in the US are frequently investigated by local law enforcement agencies or the US Coast Guard (USCG) and a proportion of them are subject to autopsies. These investigative and autopsy reports are integral to DAN’s research into the causes of diving-related fatalities. Without access to these reports, it would be virtually impossible to compile enough data for analysis.

Each state in the US has its own set of regulations regarding the release of personal health information, on top of the federally mandated HIPAA (Health Insurance Portability and Accountability Act of 1996) Privacy Rule. Some states consider investigative and medical examiner reports to be public information and release such documents readily, while others have more stringent privacy laws. In addition, within a given state, the regulations (and, hence, ease of procuring reports) can sometimes vary from county to county. As described in Section 1.2, the majority of diving deaths in the US occur in Florida and California, and these two states have relatively straightforward protocols for requesting and obtaining copies of reports.

Local investigative agencies (sheriff’s and police departments) follow privacy laws similar to those of medical examiners. However, since their reports typically do not contain private medical information, those entities are often able to release reports upon requests made under the Freedom of Information Act (FOIA). Reports on cases that have been investigated by the USCG can now be requested centrally, from Washington, D.C. However, it may take up to two years after an incident occurs before the case is closed and the report is released. The USCG follows FOIA protocols and will not release personal health information contained in their reports. A redacted copy, with all personal and identifying information removed, is usually requested. When they’re available, downloaded dive-computer profiles are also included in USCG case files, along with any available gas-analysis or equipment-testing results.


DAN uses its own Fatality Reporting Form to collect data from witnesses and family members. The form may be downloaded from the DAN website (http://www.diversalertnetwork.org/files/FATform.pdf) or requested from the DAN Research or Medical Services departments. When necessary, a family member of the decedent may be contacted to assist in the data-collection process. Family members may complete the Fatality Reporting Form and/or provide authorization for the release of the decedent’s autopsy report. The incident reporting form on the DAN website (https://www.diversalertnetwork.org/research/incidentReport/) can also be used by family members and/or witnesses to report diving fatalities or to provide additional details regarding already reported fatalities.


DAN Research maintains the diving fatality data on a secure server. Once all pertinent information has been gathered and entered into the database, the results are analyzed and published in the DAN Annual Diving Report.


Worldwide, DAN received notification of 169 deaths involving recreational scuba diving during 2016 — a 33% increase over the 2015 figure. A breakdown of this total is shown in Table 1.2-1. Only 94 of the 169 fatalities occurred in the US or Canada or involved US or Canadian citizens and thus were actively investigated by DAN. Reports were received about 75 recreational scuba deaths that occurred in other countries and that did not involve US or Canadian citizens, but, due to geographical limitations, these cases could not be investigated. (DAN also received word of 12 scuba-related fatalities that did not involve recreational divers. And fatalities associated with breath-hold diving are covered in Section 4.)

Table 1.2-1. Distribution by region and country of diving fatalities reported to DAN in 2016 (n=169).

Table 1.2-1

Distribution by region and country of diving fatalities reported to DAN in 2016 (n=169).

Table 1.2-2 shows the geographic distribution of the 2016 fatalities that occurred in the US and Canada, broken down by state and province (n=64). An additional 30 cases involved US or Canadian citizens who died while scuba diving overseas. Again in 2016, Florida had the largest number of fatalities reported to DAN, followed by California, then Hawaii.

Table 1.2-2. Distribution by state or province of scuba fatalities in the US and Canada in 2016 (n=64).

Table 1.2-2

Distribution by state or province of scuba fatalities in the US and Canada in 2016 (n=64).

Figure 1.2-1 shows the distribution of fatalities in 2016 by month, in cases where that information is known (n=92). Not much can be inferred from a single year of data, but looking at the patterns over a longer period of time, it is evident that the number of fatalities reported to DAN usually increases as summer approaches, peaks around July, and then declines as winter approaches.

Figure 1.2-1. Distribution by month of US and Canadian scuba fatalities in 2016 (n=92).

Figure 1.2-1

Distribution by month of US and Canadian scuba fatalities in 2016 (n=92).


Autopsies were available for 21 of the 94 US and Canadian cases (22%). Figure 1.3-1 shows the distribution by age and sex of the 84 cases for which that information is known. In 78% of the 94 cases, the victims were male (n=73), and in 12% of cases the victims were female (n=11). Either the age or the sex of the decedent was unknown in 4 cases. About two-thirds of the 84 decedents whose age and sex are known were 50 years of age or older; 86% (n=63) of the males and 73% (n=8) of the females were 40 years or older.

Figure 1.3-1. Distribution by age and sex of US and Canadian scuba fatalities in 2016 (n=84).

Figure 1.3-1

Distribution by age and sex of US and Canadian scuba fatalities in 2016 (n=84).

Medical history: The decedents’ medical history was, in most cases, incomplete or unknown. In 5 cases, it was explicitly reported that the victim had no known medical conditions. Any known pre-existing medical conditions are listed in Table 1.3-1, but autopsy findings discovered many more.

Table 1.3-1. Known medical history of victims of US and Canadian diving fatalities in 2016.

Table 1.3-1

Known medical history of victims of US and Canadian diving fatalities in 2016.

The true prevalence of high blood pressure and cardiovascular disease among victims is not known. Table 1.3-1 represents only the cases in which the decedent’s medical condition was known. In addition to the fact that a medical history was not available for the majority of cases, some of those who were reportedly healthy may have had undiagnosed hypertension, heart disease, or diabetes, as is often the case in the general population. For examples, see cases 1-5, 1-6, 1-8, 1-12, 1-15, 1-18, 1-20, and 1-21 in Section 1.9.

Body mass index (BMI): The decedents’ BMI was available in 23 cases (24%) — 20 males and 3 females. According to the classification of the US Centers for Disease Control and Prevention (CDC)1, 26% of known BMIs were classified as normal weight (18.5–24.9 kg/m2), 30% as overweight (25.0–29.9 kg/m2) and 43% as obese (30.0–39.9 kg/m2). Two divers were classed as morbidly obese (BMI≥40.0). Comprehensive BMI data is not available for the overall scuba diving population, so we cannot know if obesity is more common in divers than in the population at large and/or if obesity is associated with an increased risk of dying while scuba diving. What we do know, however, is that a recent paper used the above CDC classifications of BMI and described 48% of active US divers as overweight.2 This may have been a contributing factor in some of the cases in this report. For examples, see cases 1-6, 1-7, 1-9, 1-24, 1-18, and 1-20 in Section 1.9.


Information about decedents’ diving certification level was available in 23 of the 94 cases (24%), as shown in Figure 1.4-1. Decedents’ years of diving experience since their initial certification was known in only 4 cases.

Figure 1.4-1. Distribution by dive certification level for US and Canadian scuba fatalities in 2016 (n=23).

Figure 1.4-1

Distribution by dive certification level for US and Canadian scuba fatalities in 2016 (n=23).


Figure 1.5-1 shows the type of diving activity undertaken during the fatal dive. Information was available for 35 of the 94 cases (37%). At least 20 cases (21%) involved pleasure or sightseeing, 8 (9%) were training dives (not necessarily involving a student, however), and 7 (7%) involved spearfishing, hunting, or collecting game. For examples, see cases 1-2, 1-4, 1-5, 1-14, 1-15, and 1-24 in Section 1.9.

Figure 1.5-1. Primary dive activity during US and Canadian scuba fatalities in 2016 (n=94).

Figure 1.5-1

Primary dive activity during US and Canadian scuba fatalities in 2016 (n=94).

Figure 1.5-2 shows the platforms from which fatal dives began. That information was known in 42 of the 94 cases (45%). In 19 of those 42 cases, the dive began from a charter boat or a private vessel (45% of known cases), and in 18 cases it began from a beach or pier (43% of known cases).

Figure 1.5-2. Dive platform for US and Canadian scuba fatalities in 2016 (n=94).

Figure 1.5-2

Dive platform for US and Canadian scuba fatalities in 2016 (n=94).

Environment: The majority of fatal dives occurred in an ocean/sea environment (n=70, 74%), with the rest occurring in stationary fresh water (n=11, 12%) or in rivers or springs (n=9, 10%); 4 cases, including a double fatality, occurred in caves. In 4 cases (4%), a description of the environment was missing. For examples, see cases 1-7, 1-10, 1-16, and 1-17 in Section 1.9.

Visibility: Only 5 cases (5%) included information on visibility, highlighting the challenges of gathering complete data on diving fatalities.

Sea conditions: Of the 94 cases, 12 (13%) included a report on sea conditions. Calm seas were noted in 4 cases (4%), moderate seas in 5 (5%), and rough seas in 3 cases (3%). For examples, see cases 1-14 and 1-18 in Section 1.9.

Current: The current was described in 10 of the 94 cases (11%). Currents were strong in 5 cases (5%), slight in 4 cases (4%), and none in one case (1%).

Time of Day: The timing of the fatality was known in 30 of the 94 cases; 28 of those (93%) occurred during the day, and 2 (7%) occurred at night. The time of day was unknown for the remainder of the 2016 cases.

Protective suits: Whether the decedent was wearing a protective suit was known in just 12 of the 94 cases (13%). Of these 12 victims, 9 wore wetsuits and 3 wore drysuits.

Maximum depth: Figure 1.5-3 shows the reported maximum depth of the fatal dive for the 24 cases (26%) in which that information is known. Of those 24, 9 (10%) occurred in water up to 30 feet deep, 1 (1%) in water from 31 to 60 feet, 5 (5%) in water from 61 to 90 feet, 3 (3%) in water from 91 to 120 feet, and 6 (6%) in water deeper than 120 feet. Depth information was not available for 70 cases (74%).

Figure 1.5-3. Maximum depth of the fatal dive in US and Canadian scuba fatalities in 2016 (n=24).

Figure 1.5-3

Maximum depth of the fatal dive in US and Canadian scuba fatalities in 2016 (n=24).

Type of gas: The type of breathing gas being used by the victims is shown in Figure 1.5-4. The type of gas was unknown in 76 cases.

Figure 1.5-4. Type of gas used during US and Canadian scuba fatalities in 2016 (n=18).

Figure 1.5-4

Type of gas used during US and Canadian scuba fatalities in 2016 (n=18).

Breathing apparatus: Open-circuit scuba equipment was used in 26 of the 94 cases (28%), and rebreathers in 11 (12%). The breathing unit used in the remaining 57 cases was unknown.

Buddy status: At least 8 (9%) of the 94 fatal dives were intended as solo dives, but most of 2016’s dive victims started with a dive buddy. Adherence to buddy system diving is difficult to establish retrospectively, however.

When survivors notice that a buddy is missing, it does not necessarily mean that the buddy broke away intentionally; it may, rather, mean that nobody noticed the diver having the problems that eventually led to their death. Either circumstance may indicate a failure of the buddy system. Figure 1.5-6 shows the distribution by buddy status of fatal dives during 2016.

Figure 1.5-6. Buddy status during US and Canadian scuba fatalities in 2016 (n=94).

Figure 1.5-6

Buddy status during US and Canadian scuba fatalities in 2016 (n=94).


We examined each case to identify the phase of the dive during which the incident occurred and the chronological chain of events that ended in death.


We use the following dive-phase categories: a) on the surface before diving, b) underwater, c) on the surface after diving, and d) exiting the water. Dive-phase information was available in 28 of the 94 cases (30%) and was not available in the remaining 66 cases (70%). Figure 1.6.1-1 shows the distribution of this information. In the majority of the 28 cases where the information was known, the diver lost consciousness either underwater (n=11) or on the surface following the dive (n=9).

Figure 1.6.1-1. Distribution of fatalities by the phase of the dive when the deceased lost consciousness during US and Canadian scuba fatalities in 2016 (n=94).

Figure 1.6.1-1

Distribution of fatalities by the phase of the dive when the deceased lost consciousness during US and Canadian scuba fatalities in 2016 (n=94).


DAN’s determination of the causes of the reported fatalities was based on the following sources of information: a) the autopsy findings and/or the underlying cause of death as reported by the medical examiner; b) the victim’s dive profile; c) the sequence of events as reported by witnesses; d) the findings from analyzing the victim’s equipment and gas supply; and e) the expert opinions of DAN reviewers. This process is described in further detail in a published paper.3 Root causes, mechanisms of injury, and causes of death could not be established in 62 of the 94 cases (66%), usually because of missing information and/or inconclusive investigative results. Based on the 32 cases for which such information was available, the most common triggers were an underlying health problem (15%) or equipment malfunctions or problems (15%). See Table 1.6.2-1 for more details.

Table 1.6.2-1. Triggers for US and Canadian fatalities in 2016 (n=32).

Table 1.6.2-1

Triggers for US and Canadian fatalities in 2016 (n=32).

The most commonly identified harmful events, or actual mechanisms of injury, were insufficient breathing gas (12%), panic (9%), and rapid ascent (9%). See Table 1.6.2-2 for more details.

Table 1.6.2-2. Mechanisms of injury for US and Canadian scuba fatalities in 2016 (n=32).

Table 1.6.2-2

Mechanisms of injury for US and Canadian scuba fatalities in 2016 (n=32).

The cause of death as established by medical examiners, in most cases, was drowning. However, according to DAN’s expert reviewers, once again the data indicated that a leading cause of disabling injuries was either a loss of consciousness or an acute cardiac event. Tables 1.6.2-3 and 1.6.2-4 list the disabling injuries and causes of death, respectively, and Figure 1.6.2-1 compares disabling injuries and causes of death side by side. Once again, in 2016 the leading cause of death was drowning, and the leading disabling injury that led to death was cardiovascular-related problems.

Table 1.6.2-3. Disabling injuries in US and Canadian scuba fatalities in 2016 (n=32).

Table 1.6.2-3

Disabling injuries in US and Canadian scuba fatalities in 2016 (n=32).

Table 1.6.2-4. Causes of death in US and Canadian scuba fatalities in 2016 (n=32).

Table 1.6.2-4

Causes of death in US and Canadian scuba fatalities in 2016 (n=32).

Figure 1.6.2-1. Most common causes of death (n=32) and of disabling injuries (n=23) in US and Canadian scuba fatalities in 2016.

Figure 1.6.2-1

Most common causes of death (n=32) and of disabling injuries (n=23) in US and Canadian scuba fatalities in 2016.

For examples, see cases 1-1, 1-3, 1-5, 1-6, 1-8, 1-11, 1-12, 1-18, and 1-20 in Section 1.9.


DAN is aware of 11 recreational diving rebreather fatalities in 2016 that occurred in the US or that involved a US citizen whose body was repatriated to the US. Four of those cases are described below.

Case 1-7: Double fatality in a cave

  • Cause of death: Drowning
  • Disabling injury: Loss of consciousness
  • Mechanism: Insufficient breathing gas
  • Trigger: Equipment problem
  • 53-year-old diver’s BMI = 23.1 kg/m2
  • 38-year-old diver’s BMI = 36.5 kg/m2

A 53-year-old male, and a 38-year-old, both experienced divers. Both were on rebreathers in a cave system and did not surface as scheduled. Their bodies were recovered at 260 ffw (80 msw) and 1200 feet (366 meters) into the cave. The recovery team indicated that stage bottles were positioned appropriately; there were 16 tanks total and only 3 were empty. It is presumed the divers ran out of air during their attempt to exit the cave, lost consciousness, and drowned.

Case 1-10: Death due to CCR failure in a cave dive

  • Cause of death: Drowning
  • Disabling injury: Loss of consciousness
  • Mechanism: Hypoxia
  • Trigger: Equipment problem
  • BMI = 20.5 kg/m2

An experienced male cave diver who had been diving with a closed circuit rebreather (CCR) for over a year began to act erratically during a cave dive with a buddy. According to the buddy, the victim was not able to continue using his scooter, his trim was off, his fine motor control was off, and his buoyancy was off. He was seen starting to swim in circles and bounce off the ceiling and the floor of the cave, so other divers started assisting him out of the cave. At some point, he lost consciousness and no longer had his regulator in his mouth. The other divers clipped him to the cave line and started a body recovery procedure after surfacing and calling local emergency services. The initial finding was that he had suffered a heart attack and that all his gear was functioning properly. A later examination found that water in his unit may have led to water-blocked oxygen cells and thus a hypoxic mix. The witnesses’ description of the diver’s behavior suggests a loss of consciousness due to hypoxia rather than a heart-related cause of death.

Case 1-16: A death during a risky drill

  • Cause of death: Drowning
  • Disabling injury: Loss of consciousness due to hypoxia
  • Mechanism: Oxygen bottle turned off
  • Trigger: Blackout drill
  • BMI = 36.5 kg/m2

A 41-year-old male diver, a rebreather student, died during a training dive in the cavern portion of a cave. The information on this case is contradictory; however, as best as can be determined from various reports, the victim died during a blackout drill and was found floating while the instructor was possibly still at depth. According to one account, the victim’s was blocked by a neoprene cover and his oxygen bottle was turned off. By another account, at 35 fsw (11 msw), while ascending, the lead instructor saw the victim take his regulator out of his mouth and started moving his mouth in different directions. She asked him, using hand signals, if he was OK, and he signaled back yes and put the regulator back in his mouth. After a few seconds, she saw that his regulator was out of his mouth again and that his safety equipment was blinking red. She then saw him fall two feet to a ledge. She inflated his wing to get him to the surface. Another team assisted when the victim floated up and got stuck at the top of the cavern. They got him to the surface where cardiopulmonary recuscitation (CPR) was commenced, but he could not be resuscitated and was pronounced dead in the emergency room.

Case 1-17: VGE following a long dive

  • Cause of death: Decompression sickness
  • Disabling injury: Decompression sickness
  • Mechanism: Rapid ascent
  • Trigger: Current in cave
  • BMI = 35.6 kg/m2

A 46-year-old male, an experienced CCR instructor, complained of chest pain and shortness of breath immediately after surfacing from a 4.5 hour solo cave dive. He started coughing intensively and he was transported to a local hospital where he later died. Vascular gas emboli (VGE) were found in the mesenteric and portal venous system, in the inferior vena cava, and in his pulmonary artery. The coroner ruled the cause of death to be Type 2 decompression sickness (DCS).


About half of all 2016 recreational diving fatalities reported to DAN occurred in the US or Canada. Table 1.2-1 highlights the fact that diving fatalities are a global hazard, occurring in tropical seas and colder waters alike. In the US, the two states with the highest number of fatalities in 2016 were, as in previous years, Florida and California — states whose diving milieus likewise range from tropical conditions to colder waters requiring drysuits. As a result, many of the issues discussed in this section will apply to divers all around the world.

In 2016, 4 out of 5 decedents were male. While this ratio cannot be compared with the diving population at large, because it is unknown exactly how many divers there are or how many dives any given diver makes, this proportion is similar to that reported in previous years. Once again, BMI data are a cause for concern, especially in light of both pre-existing medical conditions and the high proportion of known causes of death associated with cardiovascular health. Overweight individuals with known heart conditions need to consider carefully if diving is the sport for them. If they decide it is, then they should get in shape for the exertion they will inevitably encounter while diving.

Rebreathers continue to increase in popularity on dive boats and in their prevalence in DAN’s annual fatality reports. Concurrent with this increase has been an increase in fatalities at depths greater than 130 fsw (40 msw). This apparent growth in recreational “technical” diving continues unabated, and DAN has been actively engaging the technical diving community through magazine articles and presentations at dive shows and workshops. We encourage all recreational divers to be vigilant when it comes to safety, and we encourage the technical diving community to be hypervigilant. If you see something unsafe, say something about it. You just might save a life.

Two of DAN’s important 2018 research findings2,3 should be emphasized in light of the results reported here. First, diving has an excellent safety record when it is undertaken with safety in mind. We have found that there are probably fewer than two deaths per million recreational scuba dives.4 That should serve as a pat on the back for all the dive professionals who make safety their highest priority and for the millions of divers who safely make adventurous dives. But, collectively, we make millions of dives each year, and, as these annual reports show, dozens and dozens of recreational divers die every year. The second important 2018 DAN paper highlights why this is such a tragedy. Of the most active divers in our community — those who make perhaps a couple of dives per week and who dive most weekends — about half are married and about 30% have children.2 Nearly 100 US and Canadian divers died in 2016, and exactly half were between 40 and 59 years old. This represents a terrible toll on our extended diving family. DAN urges every diver to pay close attention to safety before, during, and after every dive. Together, let us all work toward further improving our already impressive safety record by eliminating unsafe diving practices and maintaining our fitness for diving.


Case 1-1: Distress at depth

  • Cause of death: Arterial gas embolism (AGE)
  • Disabling injury: AGE
  • Mechanism: Rapid ascent
  • Trigger: Acute health problem, low on air
  • BMI = Unknown

A 41-year-old male, diving off a private boat, was on his second dive of the day. He and his son were sharing one tank with two secondary regulators. They had been at 65 fsw (20 msw) for about 25 minutes when they started running low on air. According to the son, the victim became distressed at depth, so they quickly ascended to the surface. The son called for help, and they were both pulled onto the boat; the victim was barely breathing. He soon stopped breathing, and friends administered CPR while the boat headed to shore. The victim was transported to the hospital, where he was pronounced dead. The official cause of death was reportedly “barotrauma due to acute decompression.” That diagnosis is possible, but according to DAN’s experts, considering that the decedent went into distress at depth and that toxicology studies reportedly found amphetamines, it is also possible that the disabling condition was an acute health issue.

Case 1-2: Distress during a lobster hunt

  • Cause of death: Acute heart condition
  • Disabling injury: Atherosclerotic cardiovascular disease with significant narrowing of the coronary arteries
  • Trigger: Strenuous exercise
  • BMI = Unknown

A 60-year-old male, an experienced diver, was diving solo from a boat in 8–12 fsw (2–4 msw) for lobster. On his first dive of the day, witnesses on the boat said he surfaced in distress after 45 minutes and was assisted back on board, where CPR was immediately started. He was transported to the hospital, where he was pronounced dead. The official cause of death was atherosclerotic cardiovascular disease, with significant narrowing of the coronary arteries.

Case 1-3: Equipment malfunction and panic

  • Cause of death: Drowning
  • Disabling injury: Panic
  • Mechanism: Loss of buoyancy; out of air
  • Trigger: Equipment malfunction
  • BMI = Unknown

A 67-year-old male was diving with his wife as a buddy. On their fourth dive of the day, they went to a depth of 50 fsw (15 msw). Upon surfacing, the victim had trouble inflating his buoyancy control device (BCD) due to a dump valve actuator entanglement. His buddy tried to help to fix the problem with the tangled equipment. But the victim started to panic and grabbed at the buddy, knocking off her mask and regulator. The buddy recovered her regulator and had put it back in her mouth before they started to sink. Soon they were back on the bottom. She tried to drop the victim’s weights and pull him to the surface, but she was unable to do so. She dropped her equipment at the bottom and made an emergency ascent to the surface to get help. The divemaster went down and brought the victim to the surface within minutes. However, he was not breathing and had no pulse, and a physician and nurse who were among the boat’s other passengers immediately started CPR. After an hour of unsuccessful CPR, the victim was pronounced dead.

Case 1-4: Loss of a student diver

  • Cause of death: Drowning
  • Disabling injury: Unknown
  • Mechanism: Unknown
  • Trigger: Unknown
  • BMI = Unknown

A 52-year-old male student diver was on his first dive. He initially had trouble with his fins, but the issue was resolved, according to the instructor. The victim then became separated from his group, but his companions did not realize he was missing until they surfaced; there were reportedly three divers in the party. His body was recovered 30 minutes later and he was pronounced dead at the scene. According to his wife, he had no known medical problems and was not taking any medications. An autopsy identified drowning stigmata with cerebral edema and moderate coronary artery disease.

Case 1-5: Myocardial infarction on a solo dive

  • Cause of death: Sudden cardiac death
  • Disabling injury: Atherosclerotic cardiovascular disease
  • Trigger: Exertion
  • BMI = Unknown

A 79-year-old male, an experienced diver, was diving solo, collecting lobster. He was found floating next to his boat, unresponsive. His dive computer showed that his maximum depth had been 74 fsw (23 msw) and his dive time had been 20 minutes. The water temperature was 58°F (14°C). His cause of death was listed as sudden cardiac dysfunction due to extensive cardiovascular atherosclerosis and a recent myocardial infarction (MI) — which was judged to have occurred between 12 hours and several days, or perhaps as much as a month, before his death. He also had a family history of fatal myocardial infarction. His left anterior artery was 80% to 90% occluded, and his right coronary artery was 40% occluded. He was diagnosed posthumously with hypertensive cardiovascular disease, including mild left ventricular hypertrophy and moderate bilateral nephrosclerosis. It appears that he had finished his dive, placed his catch in the boat, and was in the process of removing his gear when he suffered a heart attack. He had been diving his whole life, three to four times a week.

Case 1-6: A death before descent

  • Cause of death: Sudden cardiac death
  • Disabling injury: Dysrhythmia/immersion pulmonary edema (IPE)
  • Trigger: Immersion
  • Other contributing factors: Obesity
  • BMI = 30.1 kg/m2

A 49-year-old male diver with intermediate experience was on a solo dive. He never descended, according to his computer, and was found floating. An autopsy found mild coronary artery disease, cardiomegaly, pulmonary edema, an atrial septal defect, and hypertensive changes of the kidneys

Case 1-8: Young diver with cardiomegaly

  • Cause of death: Cardiac arrest
  • Disabling injury: Hypertensive and atherosclerotic cardiovascular disease
  • Mechanism: Natural disease process
  • Trigger: Unknown
  • BMI = 27.7 kg/m2

A 30-year-old male was making his first dive in 10 years. He was diving with nitrox to 30 fsw (9 msw) off a boat. He reportedly surfaced and signaled that he was OK but then collapsed on the ladder. CPR was performed, but resuscitation was unsuccessful. An autopsy found cardiomegaly with left ventricular hypertrophy (LVH), moderate calcific coronary artery disease, and myocardial scarring. An inspection of his equipment found that his buoyancy compensator (BC) was not working properly but that it did hold air. The coroner concluded that the cause of death was hypertensive arteriosclerotic cardiovascular disease (HASCVD) and that the manner of death was natural. The facts of the case imply a strong likelihood of an AGE, but the pathologist did a thorough exam and excluded that possibility.

Case 1-9: A morbidly obese diver in rough waters

  • Cause of death: Drowning
  • Disabling injury: Cardiac disorder
  • Mechanism: Panic
  • Trigger: Immersion
  • Other contributing factors: Morbid obesity, seasickness
  • BMI = 57.2 kg/m2

A morbidly obese 27-year-old male was seasick, vomiting, and sweating profusely during the ride out to the dive site. The seas were rough, and the victim had trouble putting on his gear and had to be assisted in that effort. At the dive site, upon entering the water, the victim started flailing and appeared to panic. He pulled off his mask and dropped his regulator out of his mouth. Another diver swam over to help, but the victim latched on to him and pulled both of them underwater. The rescuing diver managed to inflate his BCD and brought them back to the surface. They went under twice before the rescuer calmed the victim down and got him to float on his back. A divemaster instructed the victim to return the regulator to his mouth and assisted him back toward the side of the boat. The victim lost consciousness at the ladder. Due to his size, the crew was unable to haul him back aboard. An inflatable boat was used to take the victim to shore. He was transported to the hospital, where he was pronounced dead. An autopsy found cardiomegaly with LVH. The official cause of death was listed as drowning, secondary to morbid obesity.

Case 1-11: A severe decompression accident

  • Cause of death: DCS
  • Disabling injury: DCS
  • Mechanism: Rapid ascent, omitted decompression stops
  • Trigger: Equipment malfunction
  • BMI = 27.1 kg/m2

A 50-year-old male, an experienced diver, was on a deep dive to a wreck in 210 fsw (64 msw), using mixed gas. During ascent, the victim suddenly ascended rapidly, missing his decompression stop and safety stop and leaving his companions. His buddy lost sight of the victim and figured that he had over-ascended and would come back down to decompress. However, when the victim did not rejoin him, the buddy decided to cut his decompression time short and follow the victim to the surface. The buddy found the victim on the boat, unconscious, but with a heartbeat and still breathing. The buddy put the victim on oxygen and helped their third companion aboard, and they sailed back to shore. By that time, the victim was conscious and semicoherent. He was transported to the hospital, then to the nearest hyperbaric chamber, which was some distance away.

Case 1-13: A cocaine-related death

  • Cause of death: Drowning
  • Disabling injury: Sudden cardiac death
  • Mechanism: Dysrhythmia related to cocaine*
  • Trigger: Exertion
  • BMI = 22.9 kg/m2

A 33-year-old male lost consciousness while he was swimming out from the shore. He was rescued by his companions and brought to the hospital, where he died. The cause of death was ruled to be asphyxiation due to drowning. A toxicology test was positive for parent cocaine and its metabolites.

“Cocaine is a potent stimulant which affects cardiovascular system severely. The mechanism of cardiac toxicity depends on multiple factors. Cocaine increases sympathetic stimulation and causes excess catecholamine secretion. Besides, its indirect sympathomimetic effect also directly exerts cardiotoxic effect by different cellular, molecular, and ionic mechanisms, resulting in acute or chronic cardiovascular impairment. Cardiac arrhythmia and acute myocardial ischemia or infarction is the most common cause of cocaine-induced sudden cardiac death.”5

Case 1-12: Solo diver with diabetes

  • Cause of death: Drowning
  • Disabling injury: Atherosclerotic cardiovascular disease
  • Trigger: Unknown
  • BMI = 25.1 kg/m2

A 57-year-old male was seen going into the water for a solo scuba dive. He told a witness that he was experienced and had been diving for 10 years. Sometime later, the witness saw the diver floating facedown in the water and swam out to him. The victim was unconscious, so the witness towed him back to shore. The witness said the regulator was still in the victim’s mouth, and he could hear the victim breathing. Once the victim was on shore, CPR was performed. He was pronounced dead on the beach. He had 1100 psi (76 bar) remaining in his tank. The victim had a history of diabetes mellitus and hyperlipidemia. The autopsy found evidence of hypertensive and ischemic cardiac disease.

Case 1-14: Hunting lobsters in heavy seas

  • Cause of death: Drowning
  • Disabling injury: Drowning
  • Mechanism: Exhaustion
  • Trigger: Rough seas
  • Other contributing factors: Atherosclerotic cardiovascular disease
  • BMI = Unknown

A 38-year-old male was diving for lobster with a buddy in about 20 fsw (6 msw) when he signaled his buddy to ascend. At the surface, they faced strong currents and strong seas. They tried to swim back to shore but soon became exhausted. The victim sank, and the buddy retrieved him. The buddy was able to flag down a boat and had to tread water while holding onto the victim for about 30 minutes. The harbormaster came and took the pair out of the water. CPR was administered to the victim, and both the victim and his buddy were transported to the hospital. The victim was pronounced dead. The cause of death was judged to be drowning (there was lots of water in his lungs), and the manner of death was declared to be an accident. Atherosclerotic cardiovascular disease was judged to be a contributing factor.

Case 1-15: Diver with cardiac risk factors

  • Cause of death: Drowning
  • Disabling injury: Likely heart problem
  • Trigger: Exertion
  • BMI = Unknown

A 55-year-old male was diving alone for lobster. A kayaker noticed that the diver’s surface marker had not moved for 30 minutes. He paddled out to the buoy and observed the diver face up in the water, about two feet below the surface, without a mask on his face or a regulator in his mouth; the water depth at that point was about 5 feet (1.5 meters). The victim’s body was already in a state of rigor mortis; it was recovered and brought to shore by USCG personnel who happened to be patrolling nearby. The victim had three lobsters in his catch bag, and there was still air left in his scuba tank. He was a smoker and had a history of hypertension, increasing the likelihood that he experienced cardiac issues due to the exertion of the lobster hunt.

Case 1-18: Diver with coronary disease

  • Cause of death: Cardiac condition
  • Disabling injury: Ischemia
  • Mechanism: Unknown
  • Trigger: Exertion
  • Other contributing factors: Obesity, cardiomegaly with LVH and focally severe coronary atherosclerosis
  • BMI = 36.0 kg/m2

A 52-year-old male, an experienced diver, was making a shore entry with a group when a strong current separated the divers. A few minutes later, the victim called for help and said he couldn’t breathe. Two of his buddies were able to reach him, but he lost consciousness before they could get him to shore. CPR was started and he was taken to the hospital, where he was declared dead. The decedent had a history of hypertension and ischemic heart disease and had a coronary artery stent. An autopsy disclosed cardiomegaly with LVH and focally severe coronary artery disease.

Case 1-19: A rapid ascent

  • Cause of death: Drowning
  • Disabling injury: AGE
  • Mechanism: Rapid ascent
  • Trigger: Rapid ascent
  • BMI = 27.2 kg/m2

A 56-year-old male was completing his fourth instructional dive. The victim and his instructor were touring and doing a navigational dive on a reef in about 30 fsw (9 msw), when the victim suddenly turned off and went over the backside of the reef down to 80 fsw (24 msw), in a strong current. The instructor caught up to him and asked if he was OK. The victim signaled back to her that he was OK. The instructor showed him how deep they were and motioned to start ascending. After ascending about 10 feet (3 meters), the victim bolted to the surface. The instructor tried to grab the victim’s fin but was unable to hold on and surfaced shortly after the victim. The instructor told him to inflate his BCD; he started to do so orally, at which point the instructor told him to use his power inflator and to use his snorkel to swim back to the boat. During the swim to the boat, the victim stopped because he was getting tired; the instructor told him to just hold on to the line, and the crew would pull them back in. He put his snorkel back in his mouth and started kicking. At some point he stopped kicking, and the instructor could not get a response from him. She purged the victim’s regulator and put it back in his mouth. A rescue team got to them within a minute or two and took over; the instructor let go of the line and was picked up by another dive boat. When she got back to the boat, they were performing CPR on the victim and giving him oxygen. He was transported to the nearest hyperbaric oxygen (HBO) chamber, where he died. On autopsy, there was no evidence of heart disease, AGE, or pulmonary barotrauma. The resuscitation efforts, and possibly even the HBO, may have erased signs of AGE. The victim’s rapid ascent, followed by his loss of consciousness soon after surfacing, points to his having suffered an AGE, despite his brief interval of lucidity.

Case 1-20: Diver with neglected hypertension

  • Cause of death: Drowning
  • Disabling injury: Heart problem
  • Mechanism: Unknown
  • Trigger: Cardiac event
  • Other contributing factors: Obesity, cardiomegaly with LVH
  • BMI = 34.6 kg/m2

A 42-year-old inexperienced male was diving with a buddy and a divemaster. They completed their buoyancy checks and started to swim out to the dive site. The buddy looked back at one point and saw the victim go under but assumed that he had started his dive. They became separated during the dive, and the buddy did not realize that the victim had not returned after the dive. Two other divers found the victim 6 to 7 minutes later in 12 fsw (4 msw), unresponsive. He was brought to the surface, CPR was started, and he was transported to the hospital, where he was pronounced dead. His medical history included hypertension. An autopsy disclosed cardiomegaly and LVH. The medical examiner considered barotrauma but did not report any evidence of such injury, and it was left off the death certificate. The cause of death was judged to be drowning due to cardiac problems.

Case 1-21: Sudden death after surfacing

  • Cause of death: Hypertensive Heart Disease
  • Disabling injury: Heart problem
  • Mechanism: Unknown
  • Trigger: Unknown
  • BMI = 31.4 kg/m2

A 75-year-old female reported feeling unwell after diving and lost consciousness on the boat. It is not clear if she felt ill only after or also during the dive and what caused her to surface. She was airlifted to the hospital and was in and out of cardiac arrest multiple times and was defibrillated more than once in the helicopter on the way to the hospital. In the emergency department, she was hypotensive and was placed on multiple medications to maintain her blood pressure. Her pupils were fixed and dilated and her muscles were limp. Brain death was confirmed. She did not receive HBO therapy because she was too unstable and it was not known if she had suffered an AGE or a cardiac event. She was taken off life support a few days later and passed away.

1-22: Possible medication interactions

  • Cause of death: Drowning
  • Disabling injury: Loss of consciousness
  • Mechanism: Possible pharmacological effects of a multidrug cocktail she used
  • Trigger: Unknown
  • BMI = 28.5 kg/m2

A female diver in her late 50s, an experienced diver, dived to 92 fsw (28 msw) for 31 minutes on her first dive of the day, on the first day of a dive trip. She was with a group until her ascent. The dive leader watched her ascend to 30 fsw (9 msw), deploy her safety sausage, and give the OK signal. The captain of the boat saw her for a moment upright in the water as he was picking up two other divers. When he went over to her, she was on her back, unconscious, with her head under water. She was brought on board and given CPR, then brought to shore and to the hospital, where she was pronounced dead. She tested positive for multiple, redundant medications, both psychotropics and antihistamines, some of them above therapeutic levels. Her death was ruled to be an accidental drowning.

The following medications were detected:

  • Nordiazepam 0.132 mg/L (within therapeutic range)
  • Lorazepam <.025 mg/L (below therapeutic range)
  • Diphenhydramine (Benadryl) 0.505 mg/L (within therapeutic range)
  • Bupropion (Wellbutrin) 488 ng/mL (above therapeutic range [50-100 ng/mL])
  • Dextro/levomethorphan (Robitussin) 250 ng/mL (above therapeutic range)
  • Doxylamine (Unisom) 110 ng/mL (within therapeutic range)
  • Zolpidem (Ambien) 5.7 ng/mL (within therapeutic range)

Case 1-24: Lobster diver runs out of air inside a powerplant pipe

  • Cause of death: Drowning
  • Disabling Injury: Loss of consciousness
  • Mechanism: Insufficient breathing gas
  • Trigger: Entrapment in a drainage pipe
  • BMI = 34.7 kg/m2

A 47-year-old male was diving alone for lobster off the coast and did not return to his boat. He was later found dead inside a power plant pipe and was pronounced dead. The official cause of death was judged to be drowning. The decedent apparently ran out of air in an overhead environment. His equipment was tested and found to be working properly.


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© 2018 Divers Alert Network.

This work is available under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Bookshelf ID: NBK540496


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