火傷

Burns result from exposure to extreme heat, radiation, electric shock, chemicals, or friction that damages skin and underlying tissues. The injury causes cell death and can lead to massive fluid loss, dehydration, electrolyte imbalance, and potentially renal and circulatory failure. Severity depends on burn depth and total body surface area affected.

First-degree burns affect only the epidermis, causing pain and redness that heal quickly, like mild sunburns. Second-degree burns damage the epidermis and parts of the dermis, producing blisters and swelling that typically heal within one to two weeks. Third-degree burns extend through all skin layers including the hypodermis, appearing white to reddish and requiring skin grafting for treatment.

Third-degree burns damage sensory nerves and nerve endings throughout all skin layers, destroying the tissue responsible for pain sensation. Although these burns are more severe and appear white, red, or black, patients typically experience less pain because the nerves themselves are injured and cannot transmit pain signals effectively.

The Rule of Nines estimates total body surface area affected by burns in adults, assigning percentages to major body parts: the head is 9%, each arm is 9%, and the front chest and abdomen are 18%. For children, a modified rule accounts for different body proportions. This classification helps determine burn severity and appropriate treatment intensity.

Burned skin loses its protective barrier of intact layers, making it extremely susceptible to bacteria and pathogens. The damaged tissue cannot defend against microbial invasion, creating a serious threat to patient survival. Keeping the burn site clean and sterile is critical to prevent infection and promote healing.

Treatment involves intravenous fluids to offset dehydration and intravenous nutrients to enable tissue repair and replace lost proteins. Severe burns require wound cleaning, debridement, topical medications, and pain management. Full-thickness burns cannot heal independently and require skin grafting from unaffected body areas or tissue-cultured skin to restore the damaged integumentary system.

Extensive burns cause massive fluid loss leading to dehydration, electrolyte imbalance, and potential renal failure from reduced kidney function. Circulatory shock can develop as the body loses fluids and cannot maintain adequate blood pressure. Without proper treatment including fluid resuscitation and infection control, these complications can be fatal.