A nurse is reviewing the laboratory results of a client who is postoperative and has a respiratory rate of 7/min. The arteriaI blood gas (ABG) values include:

• pH 7.22
• PaCO2 68 mm Hg
• Base excess -2
• PaO2 78 mm Hg
• Oxygen saturation 80%
• Bicarbonate 28 mEq/L

Which of the following interpretations of the ABG values should the nurse make7

A. Stage III pressure injury

Stage III pressure injuries involve full-thickness skin loss, extending into the subcutaneous tissue but not through the fascia. These wounds typically present as deep craters and may involve undermining or tunneling. Non-blanchable erythema alone without visible skin loss is not characteristic of a Stage III pressure injury.

B. Stage IV pressure injury

Stage IV pressure injuries are the most severe and involve full-thickness tissue loss with exposed bone, tendon, or muscle. These wounds often have extensive tissue damage and can be difficult to manage. Again, non-blanchable erythema without visible skin loss is not indicative of a Stage IV pressure injury.

C. Stage II pressure injury

Stage II pressure injuries involve partial-thickness skin loss with damage to the epidermis and possibly the dermis. These wounds often present as shallow open ulcers or blisters and may have characteristics such as intact or ruptured blisters. While Stage II injuries can present with erythema, non-blanchable erythema specifically indicates a Stage I injury.

D. Stage I pressure injury

Stage I pressure injuries are the earliest stage and involve non-blanchable erythema of intact skin. The skin may be warmer or cooler than surrounding tissue and may have changes in sensation. There is no visible skin loss at this stage, but the area is at risk for further injury if pressure is not relieved. Therefore, non-blanchable erythema on the heels most likely indicates a Stage I pressure injury.

A serum potassium level of 3.2 mEq/L indicates hypokalemia, which is a potential complication of inhibiting aldosterone secretion and release. Aldosterone plays a key role in potassium regulation in the body by promoting potassium excretion in the kidneys. When aldosterone secretion is inhibited, potassium excretion decreases, leading to an accumulation of potassium in the bloodstream and resulting in hypokalemia. Symptoms of hypokalemia may include muscle weakness, cramping, irregular heartbeat, and fatigue.

B. Urine output of 1,200 mL in the last 2 hours:

This option does not directly relate to complications of inhibiting aldosterone secretion. A urine output of 1,200 mL in the last 2 hours indicates adequate urine production, which is generally a positive sign. However, in the context of inhibiting aldosterone secretion, the nurse would be more concerned about decreased urine output due to potential renal effects.

C. Blood osmolality of 250 mOsm/kg (250 mmol/kg):

Blood osmolality within the normal range (usually around 275-295 mOsm/kg) is not directly associated with complications of inhibiting aldosterone secretion. Blood osmolality reflects the concentration of solutes in the blood and is regulated by various factors, including water balance, electrolyte levels, and hormonal regulation. Inhibiting aldosterone secretion primarily affects electrolyte balance rather than blood osmolality.

D. Urine output of 25 mL/hr:

A urine output of 25 mL/hr is considered low and may indicate decreased renal perfusion or impaired kidney function. Inhibiting aldosterone secretion can affect renal function and urine output, leading to decreased urine production. Reduced urine output can contribute to fluid and electrolyte imbalances and may be a concern in patients with inhibited aldosterone secretion.

E. Serum potassium level of 5.4 mEq/L:

A serum potassium level of 5.4 mEq/L indicates hyperkalemia, which is another potential complication of inhibiting aldosterone secretion. Aldosterone helps regulate potassium levels by promoting potassium excretion in the kidneys. When aldosterone secretion is inhibited, potassium excretion decreases, leading to an accumulation of potassium in the bloodstream and resulting in hyperkalemia. Symptoms of hyperkalemia may include muscle weakness, irregular heartbeat, nausea, and numbness or tingling.