The epidemiology of murder and suicide involving scuba diving

Murder and suicide in involving scuba are extremely rare. A systematic search identified 19 published studies describing 4,339 recreational diving fatalities occurring between 1956 and 2011. Case vignettes identified three possible murders and eight likely suicides. These are summarised and the victims’ demography described. Prevalences of 69 murders per 105 diving fatalities and 184 suicides per 105 diving fatalities are lower than found among all cause mortality in the USA and Australia

Rock Climbing Injuries Treated in US Emergency Departments, 2008–2016

Previous research identified a trend for increasing numbers of injuries sustained while rock climbing. This study investigates whether that trend continued and describes characteristics of climbing injuries. Methods: The National Electronic Injury Surveillance System registry was searched for rock climbing injuries in US emergency departments in 2008 through 2016 among patients aged ≥7 y. Variables included each patient's age, diagnosis, injured body part, mechanism of injury, and disposition. Injuries were graded using International Mountaineering and Climbing Federation injury grades. National estimates were generated using sample weighting. Results: An estimated 34,785 rock climbing injuries were seen in emergency departments nationally, a mean of 3816 per year (SD 854). The median age of injured climbers was 24 y (range 7–77), with those aged 20 to 39 y accounting for 60% and males for 66%, respectively. Fractures (27%) and sprains and strains (26%) were the most common types of injuries. The most frequently injured body parts were lower extremities (47%), followed by upper extremities (25%). The most commonly fractured body part (27%) was the ankle. The knee and lower leg accounted for 42% of all lacerations and were 5.8 times as likely as lacerations to other body parts. Falls were the most common mechanism, accounting for 60% of all injuries. Conclusions: This study reports continued increase in annual numbers of climbing injuries. Whether this is based on a higher injury rate or on a higher number of climbers overall cannot be stated with certainty because no denominator is presented to estimate the injury rate among climbers

American Cave Diving Fatalities 1969-2007

Fatality records for American cave-diving fatalities (n=368) occurring between 1969 and 2007 were examined and circumstances preceding each death categorized. Safety rules breached were noted in each case. The number of deaths per year peaked in the mid-1970s and has diminished since. Drowning was the most frequent cause of death, most often after running out of gas, which usually followed getting lost or starting the dive with insufficient gas. Compared with untrained divers, trained divers tended to be older, died at deeper depths and further inside caves, carried more cylinders of gas and more often died alone. Untrained divers were more likely to have dived without a guideline, without appropriate number of lights and/or without adequate gas for the planned dive. Since running out of gas was associated with the greatest number of fatalities for trained divers, we recommend that gas management rules should receive the greatest emphasis in cave diving courses

Estimated workload intensity during volunteer aquarium dives

Background: This study aimed to characterize the physiological demands of working dives on volunteer divers at a public aquarium in the USA. Aims: To estimate the workloads associated with volunteer dives in a US aquarium. Methods: Participants completed a medical and diving history questionnaire. Measurements included blood pressure before and after diving and continuous ECG (Holter) monitoring during diving. Dive profiles were recorded using loggers. Mean workload was estimated from total air consumption. Results Twenty-seven divers recorded 49 air dives over 5 days. Two-thirds were male and ages ranged from 40 to 78 years. Typically, each diver made two dives with a 30-60 min surface interval. Mean heart rate while diving was 100 beats per minute (bpm). Mean estimated workload during the dives recorded during this study was 5.8 metabolic equivalents (METS), with a range from 4.1 to 10.5. The highest mean recorded heart rate was 120 bpm over 40 min, vacuuming the floor in the shark exhibit. Conclusions: Given the mean age of this sample and the prevalence of cardiovascular risk factors (body mass index, high cholesterol and hypertension), it may be prudent for aquariums to regularly monitor SAC/kg and heart rate in volunteer divers, to identify which tasks require the highest workload intensity. Divers with existing cardiovascular risk factors might then be employed in dives with lighter workloads. In conclusion, volunteer dives at this aquarium required a mean workload intensity that was described by recreational divers as moderate. The highest workload, at 10 METS for 23 min, would be considered by many recreational divers as exhausting

Epidemiology of population mortality related to falls in california 2000–2016: an increasing challenge for EMS

Background: Falls mortality increases with age and the U.S. population is aging steadily. This study examined the epidemiology of mortality in California this century due to unintentional falls. Method: Deaths caused by falls were extracted from California Department of Public Health data. Yearly Californian population estimates from the California Department of Finance were used to calculate the incidence of falls mortality. Results: There were 32 276 deaths attributed to falls, out of 618,589,117 person-years. Deaths at age ≥60 years accounted for 26 669 (83%). There were 15% more deaths during winter months, compared with summer. From age 70 mortality approximately doubled every five additional years of age. The age-adjusted falls mortality rate per 1 00 000 person-years (against the 2000 U.S. Standard Population) increased over 2000–2016 from 3.0 to 4.5 in females and from 8.9 to 9.8 in males. The number of falls deaths increased by a mean 77 per year, (95% CI 72, 83, R2=0.98, p<0.0001), doubling from 1251 in 2000 to 2582 in 2016. Conclusion: It may be prudent for EMS in California to anticipate continued increases in falls mortality. If the annual number of falls-related deaths continues to climb by an average of 77 deaths per year, then California will experience more than 3000 falls deaths per year sometime between 2025 and 2030. Recent increases were partly driven by a combination of increasing population and changes in the age distribution, however, age-adjusted mortality rates also increased, especially in females and older age groups. Conflict of interest None. Funding None

Fall from standing height, or greater, and mortality among ambulance-transported patients with major trauma from falls

Introduction: This study describes the relationship between falls from standing height, or greater, and mortality in ambulance-transported patients with major trauma from falls. Methods: Road ambulance records from 1 January 2013 to 31 December 2016 were linked with WA State Trauma Registry records to identify ambulance-transported falls patients with major trauma. Results: Of the patients who fell from standing level, 114/460 (25%) died within 30 days, compared with 47/222 (21%) who fell from height (p=0.64). Conclusion: Mortality is relatively high, and fall height is not associated with 30-day survival, among ambulance-transported patients with major trauma in metropolitan Perth, Western Australia

Biphasic effects of autophagy on decompression bubble-induced endothelial injury

Endothelial dysfunction induced by bubbles plays an important role in decompression sickness (DCS), but the mechanism of which has not been clear. The present study was to investigate the role of autophagy in bubble-induced endothelial injury. Human umbilical vein endothelial cells (HUVECs) were treated with bubbles, autophagy markers and endothelial injury indices were determined, and relationship strengths were quantified. Effects of autophagy inhibitor 3-methyladenine (3-MA) were observed. Bubble contact for 1, 5, 10, 20 or 30 minutes induced significant autophagy with increases in LC3-II/I ratio and Beclin-1, and a decrease in P62, which correlated with bubble contact duration. Apoptosis rate, cytochrome C and cleaved caspase-3 increased, and cell viability decreased following bubble contact for 10, 20 or 30 minutes, but not for 1 or 5 minutes. Injuries in HUVECs were correlated with LC3-II/I ratio and partially reversed by 3-MA in 10, 20 or 30 minutes contact, but worsened in 1 or 5 minutes. Bubble pre-conditioning for 1 minutes resulted in increased cell viability and decreased apoptosis rate compared with no pre-conditioning, and 30-minutes pre-conditioning induced opposing changes, all of which were inhibited by 3-MA. In conclusion, autophagy was involved and played a biphasic role in bubble-induced endothelial injury