LEARNING OBJECTIVE: Recall the classification and evaluation process for burns, and determine the appropriate treatment for each type of burn.
Under the broad category of environmental injuries, we will consider a number of emergency problems. Exposure to extremes of temperature, whether heat or cold, causes injury to skin, tissues, blood vessels, vital organs, and, in some cases, the whole body. In addition, contact with the sun’s rays, electrical current, or certain chemicals causes injuries similar in character to burns.
True burns are generated by exposure to extreme heat that overwhelms the body’s defensive mechanisms. Burns and scalds are essentially the same injury: Burns are caused by dry heat, and scalds are caused by moist heat. The seriousness of the injury can
be estimated by the depth, extent, and location of the burn, the age and health of the victim, and other medical complications.
Classification of Severity
Burns are classified according to their depth as first-, second-, and third-degree burns (as shown in figure 4-47).
Figure 4-47.—Classification of burns.
FIRST-DEGREE BURN.—With a first-degree burn, the epidermal layer is irritated, reddened, and tingling. The skin is sensitive to touch and blanches with pressure. Pain is mild to severe, edema is minimal, and healing usually occurs naturally within a week.
SECOND-DEGREE BURN.—A second-degree burn is characterized by epidermal blisters, mottled appearance, and a red base. Damage extends intobut not throughthe dermis. Recovery usually takes 2 to 3 weeks, with some scarring and de-pigmentation. This condition is painful. Body fluids may be drawn into the injured tissue, causing edema and possibly a “weeping” fluid (plasma) loss at the surface.
THIRD-DEGREE BURN.—A third-degree burn is a full-thickness injury penetrating into muscle and fatty connective tissues, or even down to the bone. Tissues and nerves are destroyed. Shock, with blood in the urine, is likely to be present. Pain will be absent at the burn site if all the area nerve endings are destroyed, and the surrounding tissue (which is less damaged) will be painful. Tissue color will range from white (scalds) to black (charring burns). Although the wound is usually dry, body fluids will collect in the underlying tissue. If the area has not been completely cauterized, significant amounts of fluids will be lost by plasma “weeping” or by hemorrhage, thus reducing circulation volume. There is considerable scarring and possible loss of function. Skin grafts may be necessary.
Rule of Nines
Of greater importance than the depth of the burn in evaluating the seriousness of the condition is the extent of the burned area. A first-degree burn over 50 percent of the body surface area (BSA) may be more serious than a third-degree burn over 3 percent. The Rule of Nines is used to give a rough estimate of the surface area affected. Figure 4-48 shows how the rule is applied to adults.
Figure 4-48.—Rule of Nines.
A third factor in burn evaluation is the location of the burn. Serious burns of the head, hands, feet, or genitals will require hospitalization.
The fourth factor is the presence of any other complications, especially respiratory tract injuries or other major injuries or factors.
The medical technician must take all these factors into consideration when evaluating the condition of the burn victim, especially in a triage situation.
After the victim has been removed from the source of the thermal injury, first aid should be kept to a minimum.
Aid Station Care
Once the victim has arrived at the aid station, observe the following procedures.
All major burn victims should be given a booster dose of tetanus toxoid to guard against infection. Administration of antibiotics may be directed by a physician or an Independent Duty medical technician.
If evacuation to a definitive care facility will be delayed for 2 to 3 days, start topical antibiotic therapy after the patient stabilizes and following debridement and wound care. Gently spread a 1/16-inch thickness of Sulfamylon® or Silvadene® over the burn area. Repeat the application after 12 hours, and then after daily debridement. Treat minor skin reactions with antihistamines.
Sunburn results from prolonged exposure to the ultraviolet rays of the sun. First- and second-degree burns similar to thermal burns result. Treatment is essentially the same as that outlined for thermal burns. Unless a major percentage of the body surface is affected, the victim will not require more than first aid attention. Commercially prepared sunburn lotions and ointments may be used. Prevention through education and the proper use of sun screens is the best way to avoid this condition.
Electrical burns may be far more serious than a preliminary examination may indicate. The entrance and exit wounds may be small, but as electricity penetrates the skin it burns a large area below the surface, as indicated in figure 4-49. A medical technician can do little for these victims other than monitoring the basic life functions, delivering CPR, treating for shock if necessary, covering the entrance and exit wounds with a dry, sterile dressing, and transporting the victim to a medical treatment facility.
Figure 4-49.—Electrical burns.
Before treatment is started, ensure that the victim is no longer in contact with a live electrical source. Shut the power off or use a nonconducting rope or stick to move the victim away from the line or the line away from the victim.
When acids, alkalies, or other chemicals come in contact with the skin or other body membranes, they may cause injuries that are generally referred to as chemical burns. For the most part, these injuries are not caused by heat but by direct chemical destruction of body tissues. Areas most often affected are the extremities, mouth, and eyes. Alkali burns are usually more serious than acid burns because alkalies penetrate deeper and burn longer.
When such burns occur, the following emergency procedures must be carried out immediately:
DO NOT attempt to neutralize a chemical unless you know exactly what it is and what substance will neutralize it. Further damage may be done by a neutralizing agent that is too strong or incorrect.
For acid burns, make a solution of 1 teaspoon of baking soda to a pint of water and flush it over the affected area. For alkali burns, mix 1 or 2 teaspoons of vinegar to a pint of water and flush it over the affected area.
When treating chemical burns to the eye, the one and only emergency treatment is to flush the eye(s) immediately with large amounts of water or a sterile saline solution. Irrigate acid burns to the eyes for at least 5 to 10 minutes with at least 2000 ml of water. Irrigate alkali burns to the eyes for at least 20 minutes. Because of the intense pain, the victim may be unable to open the eyes. If this occurs, hold the eyelids apart so that water can flow across the eye.
A drinking fountain or field “water buffalo” may be used to supply a steady stream of water. Hold the victim’s head in a position that allows water to flow from the inside corner of the eye toward the outside. Do not allow the water to fall directly on the eye, and do not use greater force than is necessary to keep the water flowing across the eye.
Never use any chemical antidotes such as baking soda or alcohol in treating burns of the eye, and do not try to neutralize chemical agents.
After thorough irrigation, loosely cover both eyes with a clean dressing. This prevents further damage by decreasing eye movement.
The aftercare for all chemical burns is similar to that for thermal burns: Cover the affected area and get the victim to a medical treatment facility as soon as possible.