Electrical Burn Injury in MidWestern Nigeria

Abstract

Electrical burn injuries have not been well reported in the literature. Though uncommon, they nevertheless cause significant multisystem injury with significant morbidity and mortality and are often associated with a high amputation rate from tissue necrosis.

We reviewed 15 patients out of a burn population of 229 patients managed at the Burn Service of the University of Benin Teaching Hospital, Nigeria from August 2009 to June 2011.There were 13 males and 2 females. The mean age was 27.7yrs ( Range 4-43). Ten (67%) suffered high voltage (>1000V) injuries, while 3 were from low voltage. Only one occurred in the home setting. Ten were work related and 4 occurred from fallen high tension cables. The mean burn size was 21% BSA ( Range 2- 43%).There were three deaths ( 20%).

We identified electricity workers as target for preventive action and proper maintenance of overhead cables and poles as strategy to prevent electrocution from falling cables.

Introduction

Electrical burn injuries are rare compared to burns by other mechanisms such as scalds, flames and contact burns. They may present as domestic accidents from low voltage currents, occupational hazards from working with high tension wires or as natural occurrences such as lightning strikes. They are unique because they cause more severe form of injuries, are more difficult to evaluate adequately in the acute phase, and have a multi system impact from passage of current through the body, as well as the systemic effects exerted by the burning process and the well known pathology accompanying tissue damage from burns. Furthermore, victims may suffer other injuries from been ‘thrown off’ or ejected by violent muscle spasms from tetanic contractions of skeletal muscle stimulated by electric current. Though they represent a small fraction of the overall burn population, they nevertheless continue to be a major health problem globally.1

While much has been written from many centres on the epidemiology, management and outcomes from burns, there has not been as much attention given to this more devastating form of burn injury. Admittedly, there is a paucity of publication in this area2. Reliable national data on this pathologic entity is not available. However studies across Nigeria show that they represent about 4.6 to 8% of burn populations studied 3,4. Similarly, 3% and 4% of the burn population reported by Maghsoudi in Iran and Andrew Burd and colleagues in Hong Kong were from electrical injuries5,6. Only two dedicated studies were found in an online search of the English literature as well as local journals describing this entity in Nigerian populations.

Reports

Patients and Methods

We examined the admission records of the Accident and Emergency division; the portal through which emergencies trauma patients are admitted and the ward admission records into the Burns ward to identify the index population. The medical records of these patients were studied with additional information obtained from the nurses’ case records, charts and change book. As the cases were seen, we also took a prospective interest in subsequent cases. Thus, this is both a retrospective and prospective look. Information obtained included patients demographic data, cause and circumstance of injury, pattern of injury, burns size, management and management outcome.

Stabilisation protocol followed the ATLS guidelines as adapted for burns with emphasis on airway protection, fluid management and monitoring with particular attention to urine output, analgesics, detection of associated injuries and wound management. Tetanus immunisation was updated after initial stabilisation. Clinical parameters of pulse volume and character were used to assess the heart as continuous electrocardiographic monitoring was not routinely available. Definitive wound care was administered by the plastic surgeons. Photographic documentation was carried out among other relevant investigations. The figures are presented in simple descriptive statistics.

Results

There were fifteen ((6.6%) patients seen of 229 patients admitted for burns from August 2009 to June 2011. Of these thirteen were males and two were females giving a male to female ratio of 13: 2.

The age ranged from four years to 41 (mean= 27.7). Two were children aged 4 and 14 respectively. Twelve were adolescents and young adults aged 19 to 38 and only one patient was 41 as shown in Figure 1.

Four were students: two school pupils, 2 undergraduates. There were 2 artisans and one trader, 3 worked in the electrical department of the hospital while the others were staff of the national electrical corporation as shown in Figure 2.

There were five low voltage injuries and ten high voltage injuries. One patient suffered low voltage injury in domestic setting, 4 were injured from low voltage work related injuries. 4 were injured from fallen high tension cables and 4 sustained injuries while working near or on transformers and the others while working with high tension wires as in Figure 3.

A 22 yr old female undergraduate sustained 2% superficial partial thickness burn from shocks received in the bathroom from faulty electrical fittings.

Burn size ranged from 2 to 43% (mean=21%). Burn depths were partial thickness, full thickness or a combination of both. The regions involved were the extremities, trunk, head and neck, and the perineum as shown in Figure 4.

Four (26.7%) patients required an amputation and there were three (20.0%) deaths from overwhelming sepsis.

Conclusions

Increasing number of electrical burn injuries are presenting in our burn service. Electricity workers are a vulnerable group as highlighted by this study. Fortunately, these are a subset of the population who are easily accessible and should be a focus for education and preventive action. Industrial safety rules should be taught and enforced. Falling cables are a menace and regulatory authorities need to ensure regular maintenance of overhead cables to safeguard the innocent population who often suffer the pains and economic burden of injury. There is a need to establish a national burn registry for accurate documentation of burn injuries. These will provide data for national planning on prevention and management.

Discussion

Electrical burn is a major problem representing 6.6% of the total burn population in our centre in the period under review. This is only a little higher than the 4.6% found in Enugu3. Okpara et al7 managed 24 cases over a ten year period in Enugu. Given the time frame covered by this study, it is very likely that more cases will be seen in our centre. This may reflect a truly higher incidence or just a reflection of variation in the burn workload. In yet another study from Lagos, Nigeria, 10 (9.4%) of 106 acute burns treated over a five year period were from electrical injury9. Burn injury from electricity has been described as the second most important cause of admission to burns unit worldwide10. Indeed, electrical burn injury varies in incidence from 6% in the US to 20% in some Asian and African burn units10. As the nation drives for increased power generation and utilisation, the risk is expected to increase. It is therefore necessary to incorporate preventive programs and safety measures early to checkmate this scourge.

The male population is more at risk representing 87% of our study population. This is in consonance with the finding of other workers with a male preponderance ranging from 71.4% to 98.0%5,11,12,13. This is not surprising because women are usually exposed in the home setting from faulty electrical fittings and appliances. One of our female patients sustained burns in the bathroom from such accident. Other occurrences involving women are as a result of accidents. The other female got burnt when the vehicle she was travelling in crashed into an electric pole and the high tension cable fell. Males often suffer electrical burns in the course of their work. In children, a common mode of injury is when children in their exploratory behaviour chew on cords of electrical appliances causing perioral burns. In this instance, sexual predilection is not as much in favour of males. Indeed in the children population, sex ratio varies from 1:1to 2:110.

We did not encounter this type of injury in children probably because these appliances are not usually available in many homes and poor power supply has shifted attention to alternative sources of energy.

Most of our patients are young adults. This is the pattern reported in other studies. Electrical burn injuries are largely work related. A third are said to occur in electrical workers, another third in construction workers. It causes about 1000 deaths annually in industrial workers in the United States14. The ensuing death or disability results in significant economic loss. This highlights the need to emphasize industrial safety regulations and safe practices. Casualisation of workers in this technical field should be discouraged as they are not likely to be well trained.

High voltage injuries were predominant in this series accounting for two thirds of cases. This is at variance with the findings of Opara et al7. However, Maghsoudi et al5 also reported a preponderance of high voltage injuries. Ikpeme et al8 reported three cases of work related high voltage injury from Calabar, South Eastern Nigeria. An earlier report from the same centre did not document any case of electrical burns in the study period between 2005- 200815. A major highlight of our finding is the contribution from falling high tension wires. There is the need for strict adherence to installation standards, regular maintenance and perhaps insulation of these cables. There may be a need to shift gradually to the use of underground cables as wholesale replacement may not be fiscally prudent in a struggling economy.

Electrical burn is associated with deep injuries which may not be immediately obvious at presentation. The degree of injury depends on the current’s intensity, duration of contact and tissue resistance. This often requires extensive debridement and amputations.

Four (26.7%) of our patients required amputations. Two of these needed their amputation revised at a higher level. This is similar to the findings of Opara et al7 who found an amputation rate of 29%. Celik, et al16 also found an amputation rate of 26% in a review of 38 consecutive paediatric electric burns in Turkey. A major limb amputation rate of up to 35% has been reported17. This causes considerable disability and lifelong psychosocial scar. A major lesson learnt during the revision of an arm amputation in one of the patient ( Fig. v) is the need to secure the subclavain vessels at a higher level to prevent axillary artery blow out. This has been well described in the literature10.

There were 3(20%) deaths mainly from sepsis. These had major burns of 40% and above, required multiple debridement and amputations. Challenges in these patients were those of finance, skin coverage and poor nutrition. Although there are lower case fatality is some centres, the preponderance of high voltage injury in our series would in part explain this fatality. Figures like this are however not unusual in this population of patients. Indeed, the usual case fatality is quoted to be in the range of 20- 30%. 18

Fig 1.

Age distribution.

Fig 2.

Occupational Distribution

Fig 3.

Circumstances of the burns

Fig 4.

Burn size ( %BSA)

Fig 5.

A bricklayer burnt while plastering the perimeter fence of a transformer station

Fig 6.

Hand burn from contact with high tension wire

Fig 7.

High voltage burn from falling cable