CLINICAL Cutaneous chemical burns: assessment and early management Neiraja Gnaneswaran, Eshini Perera, Marlon Perera, Raja Sawhney Background urns are a common trauma that affects up to 1% of the Australian population and may be associated with Chemical burns are common and may cause significant B significant physical, psychological, social and economic physical, psychological, social and economic burden. Despite burden.1 Chemical burns represents 3–5% of all burns-associated a wide variety of potentially harmful chemicals, important admissions.2 Despite the small proportion, chemical burns general principals may be drawn in the assessment and initial account for 30% of burns-associated death,3,4 most commonly management of such injuries. Early treatment of chemical burns occurring as a result of chemical ingestion. Given the nature is crucial and may reduce the period of resulting morbidity. of injury, hospitalisation tends to be prolonged and healing is Objective delayed. Many substances that are freely available in the community, This article reviews the assessment and management of either occupational or domestic items, have the potential to cause cutaneous chemical burns. chemical burns. The immediate availability and poor labelling of these substances has accounted for an increase in unintentional Discussion chemical burns. Assault and suicidal attempts account for the remaining cases of chemical burns. The affected population is Assessment of the patient should be rapid and occur in conjunction with early emergency management. Rapid history generally evenly distributed but an increase in paediatric chemical 5 and primary and secondary survey may be required to exclude burns has been previously documented. Areas affected tend systemic side effects of the injury. Depth of wound assessment to include the face, eyes and extremities. As such, the scope is difficult given that necrosis caused by various chemicals of this review is limited to the assessment and management can continue despite cessation of exposure. Early management of cutaneous chemical burns. Ocular burns should be urgently should be conducted with consideration of clinician’s safety, referred to an appropriate ophthalmic service. and appropriate precautions should be taken. Excluding More than 25,000 chemicals are used commonly in industrial specific situations and chemical exposure, copious irrigation and domestic settings. The diversity of harmful chemicals results with water remains the mainstay of early management. in a vast array of clinical sequelae and a short review would not Referral to a centre of higher acuity may be required for expert suitably cover the relevant treatments. The current publication evaluation. is aimed to provide principals in the assessment and general management of chemical burns. Keywords Pathophysiology and types of chemicals burns, chemical; wounds and injuries; skin The pathological end result of chemical burns, regardless of the type of chemical, is consistent with changes occurring during thermal burns. The external toxic stimulus causes denaturation of biological proteins and thus renders them physiologically REPRINTED FROM AFP VOL.44, NO.3, MARCH 2015 135 CLINICAL CUTANEOUS CHEMICAL BURNS inactive. This inactivation of essential results in disruption of physiological or solid), concentration, quantity, proteins results in cell death. Thermal processes. duration of cutaneous contact, extent burns tend to cause rapid coagulation • Inorganic solutions: cause injury by of penetration and initial emergency of protein due to protein crosslinking. denaturation mechanisms as outlined management.7 By contrast, chemical burns cause above. denaturation of physiological proteins General prinicples of through six different processes including Assessment management reduction, oxidation, corrosion, vesication, 1. Personal protection equipment: it is After primary survey and initial rapid dessication and protoplasmic poisoning.6,7 vital that the treating clinician wears assessment, the following care outlines It should be noted that many chemicals protective clothing to prevent injury the general principles for managing acute cause injury through combinations of (eg gloves, safety googles). chemical burns.11 these processes. 2. Primary and secondary survey: as with 1. Removal of the chemical: the duration Chemical agents can also be classified any clinical presentation, the patient of skin contact is the key determinant on the basis of the induced chemical must be stabilised using principals of injury severity.12,13 Thus, prompt reaction that the agent initiates. of primary survey. This should be removal of chemical contact is Such classification may be useful for completed in a rapid and systematic mandatory. consideration of early management approach. a. This should be performed rapidly options. Chemical agents may be a. Airways: ingestion of chemicals, and generally requires removal of classified into one of these categories particularly alkali agents, may contaminated clothing at the scene despite slight variations in the resulting result in upper airways obstruction. of injury.14 Initially, residues or dust clinical sequelae. Stabilisation of airways and urgent should be brushed off the skin. • Acids: act as proton donors in the medical support is required. b. Irrigation should then be performed biological system. Acid injury causes a b. Breathing: special considerations with warm water under a tap with coagulative necrosis of the superficial during chemical injury include the appropriate drainage to prevent tissue. exclusion of inhalation injuries, further injury. Care should be • Bases: chemicals are proton acceptors particularly for aerosol chemicals or taken to ensure the wash off does and tend to have greater capability smoke.10 Such patients frequently not occur across unaffected skin. of producing injury.7, 8 These agents require ventilatory support and thus Early irrigation dilutes the chemical produce heat via reactions with fats, early referral should be sought prior concentration and has been shown extract water from surrounding tissue to clinical deterioration. to reduce the severity of the burn and result in liquefactive necrosis c. Circulation: smaller chemical burns and hospital stay.8 No objective (Figure 1). Such necrosis allows infrequently cause cardiovascular measure for appropriate irrigation penetration deep to the superficial collapse. Occasionally, severe has been defined in the literature wound and continues to cause injury metabolic disturbances may result but it is widely accepted that 0.5–2 despite initial removal of the insult.9 from chemical absorption and thus hours may be required to maintain a • Organic solutions: cause injury by monitoring and stabilisation may be cutaneous pH of 5–11.10 dissolving the lipid membrane, which required. c. Neutralisation of chemicals is 3. History: a rapid history should contentious but is generally not be taken simultaneously during indicated because of the risk of primary survey and initial care of further heat production and thus the cutaneous burn. It is vital that continuing injury. Several neutralising such assessment does not delay the agents have shown some benefit,9 initiation of immediate treatment. but irrigation with plain water Information regarding comorbidities remains the most efficacious, and medication may be useful. accessible and cost-effective Information regarding the chemical treatment.12,15–17 injury is important, particularly if the 2. Complete wound evaluation: the patient requires transfer to a higher microcirculation of the wound acuity service. Pertinent information is evaluated by pinprick test for includes: insulting agent (and the pain and capillary return time.18,19 Figure 1. Severe liquefactive necrosis secondary to exposure of alkaline chemical associated mechanism of injury), Assessment regarding the depth phase of the chemical (gas, liquid of the chemical burn is notoriously 136 REPRINTED FROM AFP VOL.44, NO.3, MARCH 2015 CUTANEOUS CHEMICAL BURNS CLINICAL difficult, as burns may be deceptively a. Metabolic disturbances: the most physician, referral to secondary or superficial.11,20 The difference in surface common disturbance is acid-base tertiary centres is required for formal temperature between the affected and imbalance. Monitoring blood gases assessment by specialist services. unaffected skin may assist in depth through venous sampling may be Full-thickness chemical burns may assessment.18,19 Re-assessment should necessary to ensure metabolic require admission for surgical be done at regular intervals as this stability.10,22 debridement and grafting of non- may provide information about injury b. Electrolyte disturbances and viable tissue. progression. As a general rule, unless associated sequel: various chemicals b. Ocular chemical injury is beyond the the observer can be absolutely sure, may cause biochemical disturbances. scope of this review, but generally chemical burns should be considered As such, patients may require requires urgent ophthalmic review. deep dermal of full-thickness until biochemical analysis on admission to proven otherwise. higher acuity centres. For example, Specific agents a. Chemicals causing liquefactive hydrofluoric acid (HFA) may cause Management of specific chemical agents necrosis, typically basic solutions, hypocalcaemia and resulting cardiac is complex and is generally advised in may cause continuing necrosis arrhythmia. the emergency department following dispute removal of agent.