Chemical burns from assault: a review of seven cases seen in a Nigerian tertiary institution

Summary

Chemical burns represent a major challenge for reconstructive surgeons. They are caused by exposure to acids, alkalis or other corrosive substances which result in various degrees of injury. This report highlights the challenges faced in managing such patients in a Nigerian teaching hospital. The medical records of seven patients (four females and three males) treated for chemical burns injury from January 2001 to December 2010 were retrospectively reviewed. All patients were younger than 30, with a mean age of 23.3. Most of them (85.7%) had sustained full thickness burns ranging from 8% to 33% of their body surface area. All cases were result of assaults. The male to female ratio was 1:1.3, and the average duration of hospital stay was 7.5 months. The face was affected in all patients. Patients presented with multiple deformities, like ectropion of eyelids, keratopathies, blindness, nasal deformities, microstomia, loss or deformities of the pinna, mentosternal contractures, and severe scarring of the face. Twenty-nine surgical procedures were performed, which included nasal and lip reconstruction, ectropion release, commissuroplasty, contracture release, and wound resurfacing. Management of chemical burns, especially in a developing country lacking specialised burn centres with appropriate facilities, is challenging. Prevention through public awareness campaigns, legislation for control of corrosive substances, and severe punishment for perpetrators of assaults using these substances will go a long way in reducing the incidence of chemical burns.

Introduction

Chemical burns are caused by exposure to acids, alkalis or other corrosive substances which result in various degrees of injury. In developing countries, chemical assault injuries are more prevalent than work-related chemical injuries. The head and neck region is the commonest part of the body affected in the victims of these assaults.¹ The variety of deformities that may follow this type of injury is kaleidosopic. The severe cosmetic disfigurement and multitude of functional losses like visual impairment, airway obstruction, feeding difficulties and psychological trauma will require a long series of surgical corrections and rehabilitation. Chemical burns, especially on the face, represent the most demanding and complex challenge for the reconstructive surgeon. The challenges faced by plastic surgeons in the management of such patients in developing countries is compounded by paucity of facilities, collaborating skilled manpower, late presentation and poor economic status of patients.

Patients and methods

The medical records of seven patients (four females and three males) with chemical burns managed at the University of Maiduguri Teaching Hospital, Borno State, Nigeria, from January 2001 to December 2010 were retrospectively reviewed. Information was extracted on patient demographics, total body surface area (TBSA) burned (% head involved), duration of injury before presentation, mode of injury, nature of chemical, deformities sustained, procedures performed, and challenges faced.

Results

All patients were younger than 30 (mean age 23.3), and the male to female ratio was 1:1.3 (Table I). Eightyfive per cent of patients had sustained full thickness burns ranging from 8% to 33% of their body surface area. All cases were due to assaults; love affair problems were the cause in 5 patients while robbery attacks were the cause in the remaining 2 patients. Only 3 patients presented immediately after injury, the rest presented weeks to months after injury as shown in Table I. Five patients had ectropion of the eyelids with eye involvement and variable visual loss, two had bilateral blindness (Table II). Nasal deformity was seen in four patients, with pinna loss in 2 patients. Commissural contractures and microstomia were observed in 3 patients; lip ectropion in 2 patients. One patient presented with full thickness burns of the forehead with calvarial exposure (Case 7, pictures A & B).

Table I. Demographics, percentage surface area burnt, duration before presentation, mode of injury and type of chemical used.

Table II. Deformity sustained and surgery performed.

Case 7A. At presentation.

Case 7B. At presentation.

Twenty-nine surgical procedures were done which included facial resurfacing with split thickness skin graft in 6 patients, 4 ectropion release with full thickness skin graft (FTSG), 1 commissuroplasty with skin grafting, one bilateral commissuroplasty with triangular scar excision and mucosal V-Y advancement flaps (Case 1, picture D) and mentosternal contracture release. One patient had multistage nasal reconstruction with Tagliacozzi flap, and one had calvarial trephinations and subsequent skin grafting for exposed calvarium.

Case 1D. After commissuroplasty, lip and nasal reconstruction.

Case 1A. At presentation.

Case 1B. After skin grafting and ectropion release.

Case 1C. After commissuroplasty, lip and nasal reconstruction.

Case 7C. After multiple skin grafting and contracture release.

Case 7D. After multiple skin grafting and contracture release.

Discussion

Chemical agents cause burns by various mechanisms; tissue destruction caused by acid results in coagulative necrosis while alkalis cause burns by liquefactive necrosis. Tissue damage may continue for several minutes to hours after exposure. Since severity depends on the nature, concentration, volume and duration of contact with the chemical agent, it is difficult to assess the severity of injury immediately after exposure.² The use of these agents of destruction for assault is on the increase in some African and Asian countries, with incidence in Uganda as high as 17% of all burn patients.^3-5 The nature of chemicals used in assaults is not usually known as shown in our series: assailants are typically at large. The face is the primary target area in assaults with the intent to disfigure or incapacitate their victims. In our environment, the reasons for assault were love revenges and robbery. This may explain the slight female preponderance in this series which is similar to other series reported from Bangladesh and Taiwan.^6,7

The face provides identity to an individual and features three-dimensional structures that are difficult to reconstruct. Also, scars and deformities are difficult to conceal in this region. Blacks and Orientals scar badly after chemical injuries because of their thick oily skin.⁸ Sixty per cent of our patients present with severe facial mutilation that requires a series of surgeries which are similar to those reported by Yeong et al. in Seattle USA.⁹ These patients come to the plastic surgeon with high hopes and expectations. It is advisable to let them know the limitations of facial reconstruction so as to minimise post-operative discontent.¹⁰

Fifty percent of our patients presented 2 weeks after with significant scars and deformities. Anaesthesia for these patients remains a great challenge. Limited access to airways may result from mentosternal contractures, nasal stenosis, and microstomia. Local anaesthesia was used to release mentosternal contracture in case 3, and bilateral commissuroplasties in case 1 which was suboptimal. The absence of a fibreoptic laryngoscope led to the use of a laryngeal mask airway (LMA) for releasing mentosternal contracture and ectropion in case 1. The frequent turning of the head during the procedure resulted in inadvertent extubation and the procedure was abandoned. Anaesthetic complications are common in these patients because of the long duration of the anaesthesia and multiple surgeries performed at short time intervals.¹¹

Early excision and skin grafting is the best approach in full thickness burns, this is both blood product and donor site intensive. In our cases, initial conservative management for 3 to 4 weeks before skin grafting was done partly because of late presentation, infected wound and limited blood product supply, but the high vascularity of the face leads to profound inflammation and early granulation tissue formation and fibroplasia after 2 weeks of injury.¹² In facial resurfacing, full thickness skin grafting is preferred over split thickness graft because of better aesthetic results. Tissue expanders can be used to expand donor site for full thickness skin graft which will be available for covering a large surface area with very minimal donor site morbidity.¹³ Tissue expanders are scarcely available in our environment, and when available they are too expensive for our patients.

Nasal deformity was seen in case 1, which required grafting of more than 75% of the face. Because of the paucity of local tissue and lack of microvascular setup for the use of free flap reconstruction, Tagliacozzi multistage nasal reconstruction was done. This patient would have benefited from total face reconstruction with one expanded flap as described by Sakurai et al.¹⁴ Chemical injury to the face is potentially blinding, even more so with alkalis. ¹⁵ Four patients had involvement of the eye with variable degree of loss of vision. Adepoju et al. found that in northern Nigeria, the major cause of chemical injury to the eye was work-related but blindness and disability occur more in cases of chemical assault.¹⁶

Chemical assaults are a major economic burden on otherwise overwhelmed health services in developing countries. ¹⁷ Until 12 years ago (year 2000), only two plastic surgery units existed in the northern half of Nigeria, with only two plastic surgeons catering for over 70 million people. In early 2001, our unit was established, catering for over 30 million people in the north-eastern part of the country, some parts of Cameroun and the Republic of Chad.¹⁸ Over the years, many more units have been established. However, there is no purpose-built burn centre in the country as of today, therefore burn cases are also managed in these units. In addition, only two centres, one in the south west and one in the south east, occasionally perform microvascular free tissue transfer, so skin grafting, local and regional flaps and staged distant flap transfer, and tissue expanders are occasionally used. In our setting, patients bear most of or all costs of care and most of them have severe financial constraints. The paucity of funds for multiple surgeries makes early intervention difficult to be achieved. Some of these patients manifest with different psychological trauma. Because of poor psychosocial support system, their psychological needs are often unmet. This leads to development of chronic pain, anxiety and frequent emotional breakdown, social isolation, and suicidal tendencies.

Conclusion

Management of chemical burns in black people, especially in a developing country like Nigeria - where there are no dedicated and well-equipped burns centres - can be challenging. However, prevention through public awareness campaigns, legislation to control the use of corrosive substances and severe punishment for perpetrators of chemical assaults will reduce the incidence of chemical burns. Improvements in infrastructural facilities, skilled manpower development and subsidising the cost of treatment for these patients will reduce the challenges faced.