To the Editor:
Cave exploration involves an inherent level of risk, including rock fall, cold temperatures, and contaminated air. 1 During the past decade there has been increasing research into appropriate rescue equipment and extrication techniques within cave environments; however, there are no collective data analyzing fatalities incurred while caving to help establish appropriate evidence-based medical and rescue protocols in these austere environments. 2 We conducted a study to describe the demographics, mechanisms, and characteristics of caving fatalities occurring within the United States. This study was declared exempt by the University of Virginia from full Institutional Review Board review.
This study is a retrospective analysis of caving fatalities in the United States from 1980 to 2008, collected and documented by the National Speleological Society (NSS)-American Caving Accidents (ACA) annual publication. Methodology was similar to a prior article regarding the epidemiology of caving injuries in the United States 3 and describes a specific subset of these data. In brief, incident reports are voluntarily provided to the NSS by caving and rescue teams and submitted in the standard format available on the NSS website. 4 These incident reports are compiled and published in an annual NSS-ACA publication. A single author (A.S.) reviewed and analyzed all incident reports listed in each yearly publication.
During the study period, there were 877 incident reports involving 1356 individual cavers. During this time, 81 fatalities occurred, which constituted 6% of all individuals with a reported incident. There were no deaths reported in the years 1981 and 2005, and data were not available for 1994 and 1995. For years with available data, there was an average of 3 deaths per year, with a maximum of 9 deaths in 1993. There was no evident linear trend in the number of deaths per year (P = .368). Although overall caving incidents and injuries occur more often in summer months, caving fatalities varied little by season. 3 Of the 26 states and 1 US territory that reported fatalities, the majority of fatalities were reported from Tennessee (n = 10; 12.4%), Alabama (n = 8; 9.9%), and Missouri (n = 7; 8.6%).
Among fatalities with reported ages, ages ranged from 10 to 59 years old (mean, 28.7 years). The mean age (years) was 29.2 in men and 26.5 in women. Those 20 to 29 years old accounted for one third of all reported fatalities (n = 27), followed by those 10 to 19 years old (n = 18). The majority of fatalities were reported among men (n = 68; 84%) and were most reported among men 20 to 29 years old (n = 24; 29.6%). The most common mechanisms leading to death were caver fall and drowning, with 24 (30%) deaths each. Flooding, with subsequent drowning, led to the largest multiple-casualty event, with 6 persons involved. Cardiac disease was the most common medically related death, accounting for 9 (11%) deaths. Two individuals (2.5%) died of exposure to toxic gases (bad air). Only 1 individual during the study period died as a result of harness hang syndrome.
Of the 29 cavers who died of traumatic injuries, 38% sustained diffuse/generalized trauma and 34% sustained a head injury; these two categories were the #1 and #2 most frequently injured body zones, respectively. Seven individuals who sustained head trauma were not wearing a helmet. Based on analysis of the precipitating event leading to death, it was determined that inexperience contributed to 26 (32%) deaths.
Of all the incidents that occurred, 49 (60.5%) deaths occurred immediately. This was most often because of drowning (n = 18) or fall (n = 15). An additional 20 (24.7%) deaths occurred before the arrival of rescue teams. These 2 time intervals established that 85.3% of all deaths occurred before rescue arrival, with the remainder of deaths occurring at some time during the rescue efforts. Of all the deaths that occurred, only 2 cavers lived long enough to exit the cave (both fall injuries).
Although this data set is limited, it appears that awareness of safety and proper planning is the most important factor in preventing deaths. In a large proportion of deaths, it was speculated that caver inexperience contributed to the fatality. Although this is a subjective interpretation of one author based on the reports, we speculate that improved training may reduce the number of fatalities. As an example, 7 cavers who sustained head trauma were not wearing a helmet. This important safety measure could potentially have improved their outcome. In addition, as many deaths occurred before rescuer arrival, it is possible that improved knowledge of first-aid techniques may have prevented these fatalities.
It is our intention that with this initial evaluation and with continued data collection, medical knowledge of caving fatalities can be enhanced to provide greater benefit to rescuers and cavers in need.
We are grateful for the help and expertise of Ray Keeler, previous Editor of American Caving Accidents, and the National Speleological Society.