Burns and fire-related injuries remain a leading cause of death among the elderly [10]. The mortality rate for burn injury has markedly declined in the past 20 years, particularly in young adults and children [12, 35]. Likewise, mortality in the elderly has decreased since 2001 [34, 40]. Yet the overall mortality of the elderly after burn injury remains markedly higher than in either children or young adults [40]. The higher burn mortality in the elderly may be attributable to many factors, ranging from comorbidities to the effects of aging on wound healing. A working knowledge of the treatment of burn injury in the elderly is important, as the number and proportion of the elderly is increasing rapidly: it is estimated that the 40.3 million people aged 60 or over in 2010 will increase to 88.5 million by 2050 [44]. The purpose of this chapter is to discuss the epidemiology, pathophysiology, treatment, and outcomes of the elderly burn patient.

The epidemiology of burn injury in the elderly (defined as ≥65 years of age) has been described both in the USA and internationally. Overall, the elderly constitute approximately 9–10 % of burn injuries documented in national registries [5, 40]. The majority of burn injuries in the elderly occur at home, particularly in the kitchen and bathroom [25, 26, 36]. It is not surprising, given their decreased mobility, that the elderly are more frequently burned within the home in locations where the majority of the activities of daily living occur. The predominant etiology of elderly burns is due to flame (32 %) or scalding liquid (16 %) burns. Contact burns, electrical burns, and chemical burns occur less frequently (<2 % for each type) [5] Although somewhat variable between studies, there is a larger proportion of elderly women sustaining burns compared to adults or children, and women tend to sustain more scald and contact injuries than men [2, 4]. Flame burn injury tends to have a higher mortality, likely due to the extent and depth of a flame burn [11, 43].

Outcome predictors for elders with burn injury share characteristics with their younger counterparts, but additional factors also come into play in the elderly. Age, inhalation injury, and burn size (regardless of age) are independent predictors of burn mortality [26, 40, 45]. Total body surface area (TBSA) burn size, in particular, has a greater effect on outcomes in the elderly. The impact of burn injury increases mortality in the elderly with each decade of age. Comorbidities, such as dementia, cardiorespiratory disease, smoking, and alcoholism increase the incidence and severity of burn injury on the elderly [4, 10, 17–19].

Changes in skin associated with aging may also play a role in elderly burns. Intrinsic aging (ubiquitous changes due to the aging process) and extrinsic aging (caused by exposure to light, chemicals, or environmental factors) both impact wound healing [14, 31]. As part of the aging process, the skin undergoes both epidermal and dermal changes. Epidermal changes include changes in melanocytes (15 % decline per decade, increased density on sun-exposed skin, and increased lentigines) and Langerhans cells (reduced density and responsiveness). Although the epithelium thins with aging, the epidermis thickens from exposure to the environment, and the epidermal-dermal junction flattens. Changes in the rete pegs decrease shear strength of the epidermis. Dermal changes include decreased collagen (1 % annual decline), dermal atrophy, loss of dermal appendages, loss of elasticity, decreased glands (dry skin), loss of immune cells, and thinning of the subcutaneous fat, all of which make the patient more susceptible to a full thickness burn injury [1, 13].

Other skin changes associated with aging are not restricted to the dermis or epidermis. The elderly experience decreased cold/warm sensation in a distal to proximal direction, making them unable to detect a thermal injury [14, 15]. The elderly have decreased angiogenesis, impaired lymphatic drainage, loss of vascularity, and skin hydration, all of which can impair healing. Finally, the elderly lose lean muscle mass and adipose tissue, increasing their risk of deep tissue injury.

The majority of burns in the elderly involve <10 % TBSA, and only 11 % have inhalation injury [34]. Extremities are most commonly injured, followed by the trunk and head [5]. One of the key differences between the elderly and the young is the incidence and impact of comorbidities on injury. Multiple diseases directly impacting the skin include atherosclerosis-(perfusion), diabetes (keratinocyte migration, perfusion), and congestive heart failure (perfusion). Hence, morbidity and mortality after burn injury may be related to comorbidities [27]. The presence of a single comorbidity in the elderly increases mortality by 1.37, an effect that does not occur in children or adults, and three or more comorbidities doubles mortality for the elderly. (Taylor [42], submitted for publication) However, the influence of comorbidities on patient function may be variable. Promising research measuring elderly frailty at admission have demonstrated a correlation between frailty and survival [37]. Other factors that may increase mortality include preexisting malnutrition and postburn complications [3, 29]. Finally, a recent study of the NBR utilized the Baux score (age + total body surface area burn) to predict mortality in the elderly. A Baux score >93 increased mortality, and mortality was nearly universal at a Baux score of ≥130 [20].

Accurate characterization of the physiologic response to burn injury in the elderly is confounded by the ubiquitous presence of comorbidities and medications administered for other pathologic processes. Recent work has suggested that the elderly respond to burn injury differently than younger adults [21]. Changes reported included a less severe hypermetabolic response (compared to younger patients) with a steady increase in metabolic needs in the first 4 weeks post-injury, higher daily average glucose levels and maximum glucose levels, greater glucose variability, increased lipolysis with increased circulating fatty acids, an abundance of saturated fatty acids, lower expression of c-peptide and GLF-1 in the acute phase, decreased endoplasmic reticulum stress response in adipose tissue, and lower myeloperoxidase in adipose tissue. The elderly may have an initial hypo-inflammatory response followed by a hyperinflammatory response with fewer macrophages and IL-1B cells. As mentioned above, the skin has both a reduced stem cell pool as well as alteration in the activation of essential signaling pathways for wound healing. The result is that patients are slow to heal wounds and have a longer hospital length of stay.

Treatment of the elderly burn patient can be challenging. The initial management should adhere to basic trauma principles: airway, breathing, and circulation. Airway and respiratory management can be particularly challenging in the elderly, who often have compromised pulmonary function prior to their injury. Patients on home oxygen for pulmonary disease at the time of their burn (and therefore hypoxic at baseline) require careful and thoughtful evaluation, as intubation may lead to death or permanent need for a tracheostomy [30]. Particular care needs to be exercised during dressing changes, as the elderly are susceptible to oversedation as well as delirium due to the changes in pharmacokinetics accompanying aging [39].

The elderly often have a narrow therapeutic window for resuscitation. Under- or over-resuscitation can lead to organ failure and death. While the elderly are often dehydrated due to diuretic use or malnutrition, they also frequently have impaired cardiac function, making the traditional urine output goal of 30–50 ml/h less useful. In general, elderly patients with burn injury >20 % should have intravenous fluid resuscitation started using standardized formulas, such as the Parkland formula (4 ml/kg/%TBSA burn, half in the first 8 h). The fluid infusion rate should be modified based on the urine output (>20 ml/h but no greater than 50 ml/h) and clinical evaluation of the patient. The ideal monitoring for the elderly burn patient has not been established. However, central venous pressures, lactate levels, and echocardiography may be helpful during the resuscitative phase. Nutrition provision is extremely important in the elderly. In addition to a decreased muscle mass, many elderly are also malnourished at the time of presentation. Nasoenteral nutrition provision should be initiated for burns >20 % in the elderly.

Burn wound closure is the goal of treatment; however, the most effective wound treatment protocol for the elderly has not been defined. Early excision with immediate grafting is the standard of care for children and adults [16, 46]. This early excision policy has been used successfully in the elderly by some groups [6, 7, 22]. Other groups have reported no survival benefit or increased complications with early operative intervention [23, 18]. We advocate a “common sense” approach that considers the elderly burn patient on a case-by-case basis based on their physiological health, response to resuscitation, and advance directives to formulate the most appropriate treatment plan. Early excision in the “healthy” elder with no comorbidities and a small hand burn is safe, efficacious, and restores an essential component for activities of daily living: the hand. However, a patient with an indeterminate depth burn on the chest and severe cardiac disease may benefit from watchful waiting to define the excision area and minimize anesthetic risk. Frailty index may, in the future, help to provide a measurable parameter that can be used to identify surgical candidates.