Pain in Burn Patients

Salahadin Abdi

Bucknam McPeek

There is physical pain, there is mental pain and scarring. You can see the outside, but what a lot of people don’t see is that we are truly burned on the inside as well.

—Burn survivor

More than 2 million burn injuries occur annually in the United States, of which thermal burns are the most prevalent; chemical and electrical burns occur less commonly. Approximately 1 in 20 patients with burn injuries require extended hospitalization. Burn injury results in both physical and psychological distress, and pain is a major component of both. In fact, burns are among the most painful of all injuries. Pain evaluation and treatment are important aspects of the care of patients inflicted with burn injuries.

The management of acute and chronic pain from burn injuries is challenging and may require input from an experienced pain specialist. A careful pain management plan will help circumvent potential hazards in these often critically ill and psychologically disturbed patients. It is important to be attentive to the specific type of pain the patient is experiencing and to the risks of pain treatment in relation to the pathophysiology of the injured patient. The likelihood of developing chronic pain and life-long suffering (e.g., chronic pain, posttraumatic stress disorder) can be reduced by appropriate and aggressive acute pain management techniques, with meticulous attention to psychological and social factors. The purpose of this chapter is to outline the essential issues so that proper planning and care can be provided.

I. TYPES OF BURN INJURY

The extent of a burn injury is measured as percentage of body surface area burned. Burns vary in depth from superficial to full thickness, with a possibility of massive destruction of muscle or bone in the latter.

In first-degree burns, the injury is superficial, characterized by erythema, and involves only the epidermis. There is usually only mild to moderate discomfort, and healing occurs within a week.

Second-degree burns are deeper, partial-thickness injuries that destroy the epidermis and variable amounts of dermis, as well as epidermal appendages. Second-degree burns are extremely painful. Most of the pain is caused by the damage of sensory nociceptive receptors that are preferentially sensitive to tissue damage. In addition to direct damage from the burn, second-degree burns damage the protective layer of skin and expose the normally protected nerve endings. These lesions heal slowly, with some tissue contraction, nerve regeneration, and the occasional need for skin grafting.

Third-degree burns destroy the skin completely. These burns are, by definition, of full thickness. Regions of third-degree burns may be painless after the initial injury for a period because of destruction of the cutaneous nociceptors. Although the central part of the initial wound may be insensate, painful areas of second-degree injury surround almost every third-degree burn. These areas heal by epidermal regeneration because some of the epidermal appendages remain intact. This healing process can be painful. With inadequate cleansing and debridement, a surface pseudomembrane that consists of wound exudate and necrotic eschar accumulates. As long as the eschar and pseudomembrane exist, the center of a third-degree burn is painless. The eschar is usually removed surgically because the unremoved eschar and membrane serve as a nidus of infection (the major life-threatening factor in burn injury). It is important to emphasize that patients with third-degree burns suffer severe pain and need treatment despite some areas of their burn being insensate.

II. TYPES OF BURN PAIN

There are two categories of pain:

Procedural pain (incidental/evoked pain): This refers to pain experienced during or after wound care, stent removal, dressing change, physical therapy, or other treatments. This type of pain is usually short-lasting but of great intensity. Debridement usually requires general anesthesia. It is helpful to administer an adequate and appropriately timed dose of a narcotic analgesic and or benzodiazepine before beginning any procedure.
Background pain (spontaneous/resting/constant pain): Background pain is the pain experienced by the patient while at rest. This type of pain is usually dull and continuous and is of lower intensity. Nevertheless, this low-intensity pain should be controlled, otherwise it may prime patients to experience more pain, as well as increase their anxiety, particularly about procedures. Background pain is best treated with opioids (or alternative analgesics) administered on a regular, rather than on an as-needed, basis.

In addition, there are two temporal components of burn pain, acute and chronic. In the acute postburn state, the most severe pain results from therapeutic procedures such as dressing changes.
Background pain may persist for weeks to months or even years. Pain related to burn injury might worsen with time because of several factors, including increased anxiety and depression, continuing sleep disturbance, and deconditioning and regeneration of nerve endings (possible neuroma formation, known as postburn neuralgia). Chronic pain may result from contractures, nerve injury (neuropathic pain), or nerve and tissue damage subsequent to surgical procedures.

III. TREATMENT OF ACUTE BURN PAIN

The main treatment goal for serious burns is the removal of necrotic tissue and other sources of infection; this requires cleaning the burn area by debridement or surgical excision. Microorganisms that release exotoxins and endotoxins exacerbate the inflammation already present in burns and quickly colonize retained necrotic tissue. After removal of necrotic tissue by cleaning or surgical excision, the next step is to promote coverage of the open wound wherever possible by a skin graft from unburned areas of the patient’s own body. In large burns, autologous skin grafts or artificial skin can provide temporary coverage.

Only gold members can continue reading. Log In or Register to continue