Why is capnography more sensitive than pulse oximetry for detecting respiratory depression?

Choice A rationale

Desiccation refers to the process of extreme drying out or dehydration of a wound or the surrounding skin. This occurs when the wound environment lacks sufficient moisture, leading to the formation of a dry, hard scab or crust known as eschar. Unlike the breakdown caused by excess moisture, desiccation can stall the healing process because epithelial cells require a moist environment to migrate across the wound bed and close the tissue gap effectively.

Choice B rationale

Edema is the accumulation of excessive fluid in the interstitial spaces of the body tissues, often resulting in visible swelling. It is typically caused by increased capillary pressure, decreased plasma proteins, or lymphatic obstruction rather than external moisture exposure. While edema can impair wound healing by reducing local blood flow and oxygenation to the tissues, it is a systemic or localized internal fluid imbalance issue, not the surface softening described by the term maceration.

Choice C rationale

Maceration is the specific term used to describe the softening, whitening, and eventual breakdown of skin resulting from continuous exposure to moisture. This often occurs under saturated dressings or in skin folds where perspiration or wound exudate collects. Macerated skin is more friable and susceptible to infection and further tissue damage. Preventing maceration involves using moisture-barrier ointments and ensuring that wound dressings are changed frequently enough to manage drainage without saturating the surrounding healthy skin.

Choice D rationale

Pressure is a mechanical force that compresses skin and underlying tissues, often against a bony prominence, leading to ischemia and tissue necrosis. While pressure is a primary cause of pressure ulcers, it describes the physical weight or force applied to the area rather than the chemical or physical breakdown caused by moisture. Moisture can certainly exacerbate the effects of pressure by making the skin more vulnerable to friction and shear, but the terms represent different mechanisms.

Choice A rationale

Zinc is a vital mineral that serves as a cofactor for many enzymes involved in DNA synthesis, cell division, and protein synthesis, all of which are critical for wound healing. It is particularly important for collagen formation and the inflammatory response. In a client with a nonhealing wound, assessing and supplementing zinc levels can provide the biochemical support necessary to jumpstart the proliferative phase of healing. The nurse should collaborate with the provider to address this.

Choice B rationale

While adequate caloric intake is necessary for healing, a specific increase in fat intake is not the primary nutritional priority for a nonhealing surgical wound. Protein, vitamin C, and vitamin A are generally more critical for tissue repair and immune function. Excess fat intake does not directly accelerate the cellular processes of granulation or epithelialization. Nutritional interventions should be balanced and focused on high-quality proteins and specific micronutrients rather than simply increasing dietary fat.

Choice C rationale

Prolonged bedrest can actually hinder wound healing by increasing the risk of pressure injuries, reducing systemic circulation, and promoting complications like deep vein thrombosis. Movement and controlled activity are generally encouraged to improve blood flow, which delivers essential oxygen and nutrients to the wound site. While rest is important for recovery, strict bedrest is rarely the most appropriate intervention for a nonhealing wound unless specifically indicated by other medical conditions or contraindications.

Choice D rationale

Reinforcing wound dressings is a reactive measure that addresses the containment of drainage but does not treat the underlying physiological reasons for the wound's failure to heal. While maintaining a clean environment is necessary, it is a standard maintenance task rather than an intervention to promote cellular healing. To truly address a nonhealing wound, the nurse must look for systemic factors, such as nutritional deficiencies or poor perfusion, rather than just adding more layers of gauze.