A patient has been admitted with a potassium level of 6.8 mEq/L. The nurse would expect which of the following electrocardiogram (ECG) changes as a result of this laboratory value?

Choice A reason:

pH 7.50, PaCO2 40 mm Hg, HCO3- 30 mEq/L. This choice is correct because it shows a high pH, a normal PaCO2, and a high HCO3-, which are consistent with metabolic alkalosis. Metabolic alkalosis occurs when there is a loss of acid or a gain of base in the body fluids, such as from prolonged nasogastric suctioning. The kidneys try to compensate by excreting more bicarbonate, but this process is slow and incomplete.

Choice B reason:

pH 7.35, PaCO2 35 mm Hg, HCO3- 24 mEq/L. This choice is incorrect because it shows normal values for pH, PaCO2, and HCO3-, which indicate no acid-base imbalance. A client with metabolic alkalosis would have an elevated pH and bicarbonate level.

Choice C reason:

pH 7.25, PaCO2 50 mm Hg, HCO3- 26 mEq/L. This choice is incorrect because it shows a low pH, a high PaCO2, and a normal HCO3-, which are consistent with respiratory acidosis. Respiratory acidosis occurs when there is impaired gas exchange or hypoventilation, leading to an accumulation of carbon dioxide in the blood. The kidneys try to compensate by retaining more bicarbonate, but this process is slow and incomplete.

Choice D reason:

pH 7.30, PaCO2 30 mm Hg, HCO3- 18 mEq/L. This choice is incorrect because it shows a low pH, a low PaCO2, and a low HCO3-, which are consistent with metabolic acidosis. Metabolic acidosis occurs when there is a gain of acid or a loss of base in the body fluids, such as from diabetic ketoacidosis or diarrhea. The lungs try to compensate by increasing the rate and depth of breathing to expel more carbon dioxide, but this process is fast and limited.

Choice A reason:

Applying warm compresses to the site and elevating the arm may help to reduce pain and swelling, but they do not address the underlying cause of the problem, which is likely infiltration or phlebitis of the IV site. Infiltration occurs when the IV fluid leaks into the surrounding tissue, causing edema, coolness, and pallor. Phlebitis occurs when the vein becomes inflamed, causing pain, erythema, and warmth. Both conditions require immediate removal of the IV catheter and restarting a new IV in another site.

Choice B reason:

Slowing down the infusion rate and documenting the findings may be appropriate actions after removing the IV catheter and starting a new IV in another site, but they are not sufficient to resolve the problem. Slowing down the infusion rate may reduce the discomfort and prevent further complications, but it does not stop the leakage or inflammation of the IV site. Documenting the findings is important for legal and quality improvement purposes, but it does not provide any intervention for the patient's pain or risk of infection.

Choice C reason:

Stopping the infusion, removing the IV catheter, and starting a new IV in another site is the most appropriate action by the nurse. This action prevents further damage to the tissue or vein, reduces the risk of infection, and restores adequate IV access for fluid and medication administration. The nurse should also apply a sterile dressing to the affected site, monitor for signs of infection or complications, and notify the physician if needed. This is the correct answer.

Choice D reason:

Notifying the physician and obtaining an order for an antihistamine is not an appropriate action by the nurse. This action implies that the patient is having an allergic reaction to the IV fluid or medication, which is not supported by the assessment findings. An antihistamine may help to reduce itching or swelling, but it does not address the cause of the pain or prevent further tissue or vein damage. The nurse should notify the physician after removing the IV catheter and starting a new IV in another site, and only if there are signs of infection or complications that require medical intervention.