Electrical burns: Epidemiological analysis of patients at the Burns Unit of the Hospital de Clínicas of the Federal University of Uberlândia
Queimadura elétrica: Análise epidemiológica dos pacientes da Unidade de Queimados do Hospital de Clínicas da Universidade Federal de Uberlândia

INTRODUCTION

The use of electric current is essential for different daily activities and can, on certain occasions, cause burns that, in addition to physical problems, are potentially fatal. They are also responsible for causing psychological and social damage¹ and, for this reason, are considered a public health problem worldwide².

Injury caused by the passage of electrical current is defined as tissue damage caused by exposure to supraphysiological electrical current. Electrical burns are classified as high voltage (≥1000 V), low voltage (<1000 V), “flash burn” (in which there is no flow of electrical current through the body of the patient), and burns caused by lightning³.

In Brazil, data published in 2016 by the Brazilian Burn Society showed that approximately one million burns occur annually, and of the patients treated in its burn units (BU), 4 - 8% are due to electrical causes^4-6. Thus, this type of burn causes approximately 1,300 deaths/year⁷; however, in the same period, the United States has approximately 1,000 victims/year⁸.

Statistics show that the prevalence is higher among men, commonly in the young population, more frequently related to work^1,8,9 and is the fourth leading cause of death related to traumatic work¹⁰.

Developed countries have made considerable progress in reducing burn death rates through a combination of accident prevention strategies and improvements in assistance to burn victims. However, most strategies have also been applied in underdeveloped countries, without much success, where 95% of burns occur, according to global statistics¹¹.

OBJECTIVE

Epidemiological analysis of patients treated for electrical burns at the BU of the Hospital de Clínicas of the Federal University of Uberlândia (HC-UFU).

METHOD

Cross-sectional study of data recorded in electronic and physical records of patients treated for electrical burns between July 2013 and June 2019 at BU. Patients treated or admitted to other services due to electrical burns were excluded.

The Research Ethics Committee (CEP) approved the research involving human beings at the Federal University of Uberlândia (Opinion No. 4,351,155).

The following variables were considered: incidence, age group, race, sex, city and environment, type of electrical current, anatomical site, extent and degree of burn, types of surgeries, length of hospital stay, and stay in the Intensive Care Unit (ICU), intentionality of injury and death.

The data were processed using frequency distribution, and percentages, and expressed in tables, with analysis carried out using the SPSS version 26.0 program.

RESULTS

Distribution by age group, incidence, sex, and race

In the HC-UFU Burns Unit, over the six years between July 2013 and June 2019, a total of 309 patients were treated for different types of burns, of which 26 were electrical burns, which corresponds to an incidence of 8.4%, represented in the following distribution: children aged 0 to 10 years 15.3% (n=4); teenagers aged 11 to 18, 11.5% (n=3); young people aged 19 to 35 26.9% (n=7); adults aged 36 to 60 years 30.7% (n=8) and older people aged over 60 years 15.3% (n=4).

In the distribution by sex, males were 76.9% (n=20) and females 23.1% (n=6), with a ratio of 3.3:1, respectively.

From the distribution by age groups and sex, 100% of the children were female; among adolescents, 100% were male; of the young people, 71% were male, and 29% were female. Of the adults, 100% were male, and of the elderly, 100% were male (Figure 1).

Figure 1 - Distribution by sex and age group of patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Figure 1 - Distribution by sex and age group of patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

From the distribution by race, 57.6% were white (n=15), 30.7% were mixed race (n=8), and 11.5% were black (n=3).

City and environment by age group where the burn occurred

The cities where the burns occurred were Uberlândia-MG, with 38.4% (n=10); Araguari-MG, with 23% (n=6); Patrocínio-MG, with 7.7% (n=2); Prata- MG, with 7.7% (n=2); and other municipalities, with 23% (n=6).

Regarding the environment where the burn occurred, the workplace was 57.7% (n=15), at home 26.9% (n=7), on public roads 7.7% (n=2), and in others 7.7% (n=2). Of workplace traumas, 66.6% were caused by high voltage and 33.4% by low voltage (Figure 2).

Figure 2 - Percentage distribution by environment where electrical burns occur. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Figure 2 - Percentage distribution by environment where electrical burns occur. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Concerning age group and environment, 75% of burns in children were at home and 25% on public roads; among adolescents, 66.6% were at the workplace and 33.3% at another location; among young people, 85.7% were in the workplace and 14.3% in another location; in adults, 75% occurred in the workplace and 25% at home, with the elderly 50% at home, 25% at the workplace and 25% on public roads. (Figure 3).

Figure 3 - Distribution by age group and environment where electrical burns occur. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Figure 3 - Distribution by age group and environment where electrical burns occur. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Type of electrical voltage of the burn by age category

During the study, it was observed that 65.4% of patients were affected by high-voltage currents and 34.6% by low-voltage currents (Figure 4). Men had high-voltage burns in 75% of cases, and women had low-voltage burns in 67%. By age category, children were affected by low-voltage in 75% and high-voltage in 25%. In teenagers, high-voltage burns were 100%. Among young people, high-voltage burns were 71.4%, followed by low voltage 28.6%. In the adult group, high and low-voltage burns were 50% for each type. Among elderly patients, high-voltage burns reached 100%.

Figure 4 - Percentage distribution of the type of voltage that reached patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Figure 4 - Percentage distribution of the type of voltage that reached patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Types of surgeries

A total of 38.5% (n=10) of patients required surgical debridement, of which 70% (n=7) were affected by high voltage current and 30% (n=3) by low voltage current. Skin autograft surgery was performed in different anatomical areas in 53.8% (n=14), flaps in 11.5% (n=3), amputations of segments of the upper limb in 7.7% (n=2), fasciotomy in 3.8% (n=1) and penile amputation in 3.8% (n=1) (Figure 5).

Figure 5 - Distribution of the percentage of type of surgery in patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

Figure 5 - Distribution of the percentage of type of surgery in patients suffering from electrical burns. Burns Unit of the Clinical Hospital of the Federal University of Uberlândia - 2013-2019.

DISCUSSION

This type of uncommon trauma has a variable incidence in the different states of Brazil, with our result (8.4%) being higher than that of developed countries (4-6%)^8,12, despite this research being carried out in a region with great progress in recent years (HDI 89.9). Uberlândia had the highest number of cases (38.4%), but it is the most populous, developed, and headquarters of the HC-UFU BU. It was followed by Araguari (23%), a city close to HC-UFU.

Of the population groups, the most affected in our region were adults, male and work-related, with a greater incidence among adolescents (66.6%), unlike the statistics observed in other studies^6,12,13. This fact is probably related to the greater participation of this group in the job market¹⁴. According to labor legislation (articles 402 to 441 of the CTL), minors under the age of 18 are prohibited from working in dangerous or unhealthy conditions.

Among children, domestic injuries were among the most common, in which parents or responsible caregivers could not always keep children under supervision. Contrary to what was seen in the literature, the victims in this study were mostly female¹⁵.

The average BBS found among all patients was similar to other studies (14.5%)9; however, as also observed in other studies, we did not find a defined correlation between the external area of electrical burn and the degree of depth of the lesions. The population group with the largest burn areas was the elderly, and this was due to their greater physical and intellectual vulnerability¹⁶.

Of the anatomical sites affected, the upper limbs were those that resulted as the most common point of origin of the trauma, as reported in other studies⁹, followed by the lower limbs¹⁷, which during its evolution was the burned area that most required surgical treatment, according to another publication whose research took place at the same BU as HC-UFU18. Debridement followed by skin autograft were the most commonly performed surgical procedures¹⁹.

Most patients, except children, suffered burns caused by high voltage current, predominantly males (75%) at their workplace (80%), similar to the results of research carried out in other BUs where victims with more severe burns^20,21.

Described as the most destructive burn trauma²², the average length of hospital stay (n=40) was higher than other types of non-electrical burns18, with a predominance of unintentional injuries and an isolated case of attempted self-extermination.

According to data collected from the Mortality Information System in the Information Technology Department of the Unified Health System, from 2000 to 2016, a male mortality of 12.9 and female mortality of 1.7 per 1 million men and women²³ were recorded due to electrical causes, however in no deaths were documented in the BU of the HC-UFU, and it may have happened that the most serious cases that arrived at the emergency department of the HC-UFU were sent directly to the ICU, where they could have died without being admitted to our service, or because a large proportion of Deaths from this type of trauma would occur at the scene of the accident, not reaching emergency services⁷ or were simply classified by another related cause of occupational death, as reported at the Third National Meeting on Safety and Health in the Electrical Sector²⁴.

CONCLUSION

There is a low incidence of patients reporting electrical burns treated at the HC-UFU BU, but the cases were in all age groups, predominantly in the adult male population and in their workplace. All children were female. Debridement surgery with skin autograft was the most commonly performed surgical treatment.

Health promotion, prevention, and protection policies regarding the dangers of electrical currents would not be practiced and disseminated among our domestic, working, or employing population, unlike in most developed countries.