Characteristics of Lethal Electrical Injuries in Central and Northeastern Bulgaria for a 27-Year Period (1980–2006)

METHODS

The study has been conducted in 6 districts of the Republic of Bulgaria on a total area of 16 910.31 km² (15.23% ± 0.54% of the whole country's territory) and a population of 1 388 277 (17.98% ± 0.06% of the whole population).¹ We have studied the forensic medical documentation from 485 autopsies caused by ET over the period 1980–2006, performed at the forensic wards in 6 districts of the country (Varna, Dobrich, Gabrovo, Ruse, Silistra, and Shumen). The statistical analysis includes comparison of means and percentages. They are carried out using SPSS Version 11. We accepted statistical significant values of P = .05.

RESULTS

For the 27-year-long period under study, 485 cases of ET have been autopsied, or 1.29 per 100000 people per year, with the population averaging 1 474 945 people¹, ² during the same period. The average age of the deceased because of ET is 37.3 ± 2.32 years (SD = 18.3). Men (85.15% ± 3.42%) (n = 413) prevail over women (14.84% ± 8.21%) (n = 72) (Fig F1) with a statistically reliable difference (t = 6.91; P < .001).

24.32% ± 7.74% cases (n = 118) are work-related accidents (0.29 per 100000 people per year on average), and 60.61% ± 5.58% (n = 294) are domestic accidents (0.74 per 100000 population per year on average) (Fig F2). The difference is also statistically significant (t = 7.45; P < .001).

Suicides by electric current have rarely been observed 7.21% ± 8.56% (n = 35) or (0.09 per 100000 people per year on average). Homicides have not been registered in our article.

Injuries by low voltage (Fig F3) 42.06% ± 6.77% (n = 204) or (0.51 per 100000 people per year on average) are more common (t = 2.15; P < .05) than those by high voltage 30.72% ± 7.40% (n = 149), which is 0.37 per 100000 people per year on average.

Seasonality is clearly marked in our study (Fig F4). Thus, 304 cases are concentrated in the summer months from June to September, which is 62.68% ± 5.43% of all deceased from electric current.

Fewer cases are observed in December: 10 (2.06% ± 8.8%), and the most in July: 92 (18.96% ± 8.00%), with significant difference (t = 2.8; P < .001). We used the smallest-square method to draw a trend of the electricity-caused injuries in the studied area. The resultant graph (Fig F5) clearly shows an ascending trend.

DISCUSSION

The analysis of our results shows that the registered average age of the deceased from ET is higher than that in other studies,³,⁴ and that male gender is predominantly affected—a fact observed not only by us⁵ but also by other authors.³,⁴

Suicides by electric current are relatively rare: 7.21%.⁶ Homicides have not been registered in our study, which implies that they are extremely rare.⁷.

We have found that deaths following low voltage injuries are prevalent. In the literature, there is not a unanimous opinion in this respect⁸,⁹. We consider that the larger number of lethalaccidents caused by low-voltage electricity result from the immensely larger access to electrical installations and low-voltage operated electrical devices.

Similar to the studies conducted by others authors, ⁴ we have ascertained seasonality in fatal accidents caused by electric current whose number increases abruptly during the summer months.

We attribute this seasonal trend to the following major factors. The electrical threshold of the myocardium for excitability is decreased with increased environmental temperature and hence the increased number of cases of ventricular fibrillations. When environmental temperature is high, skin moisture is increased and skin resistance is decreased. The summer season presupposes less clothing, and a greater lilihood of direct electrical contact with moist bare skin.

CONCLUSIONS

Among the studied cases, ET occurs in young age groups. The victims are typically men. Work-related accidents are more common than domestic ones, injuries by low voltage are observed more frequently than those by high voltage. Suicides are very rare, and not a single case of homicide has been observed in our study. The incidence of lethal accidents vary with season, increasing during the summer months.