A patient has end-stage chronic obstructive pulmonary disease (COPD). Which acid-base imbalance would be predictable in a patient with COPD?

Choice A reason: Renal failure can cause hyperkalemia because the kidneys are unable to excrete excess potassium from the body. This can lead to high levels of potassium in the blood, which can affect the heart and muscles.

Choice B reason: Diarrhea can cause hypokalemia, not hyperkalemia, because it can lead to loss of potassium from the gastrointestinal tract. This can result in low levels of potassium in the blood, which can also affect the heart and muscles.

Choice C reason: Blood transfusion can cause hyperkalemia if the blood is old or hemolyzed, meaning that the red blood cells have broken down and released potassium into the plasma. This can increase the potassium levels in the recipient's blood.

Choice D reason: Diaphoresis, or sweating, can cause hypokalemia, not hyperkalemia, because it can lead to loss of potassium from the skin. This can also lower the potassium levels in the blood.

Choice A reason: Stroke is not a cause of hyponatremia, but rather a possible complication of it. Hyponatremia is a condition where the sodium level in the blood is too low, which can affect the brain function and cause symptoms such as confusion, seizures, or coma. Stroke is a condition where the blood supply to a part of the brain is interrupted, which can cause brain damage and neurological deficits.

Choice B reason: Dehydration is not a cause of hyponatremia, but rather a cause of hypernatremia. Dehydration is a condition where the body loses more fluids than it takes in, which can affect the blood volume and the electrolyte balance. Dehydration can cause hypernatremia, which is a condition where the sodium level in the blood is too high, which can also affect the brain function and cause symptoms such as thirst, dry mouth, or lethargy.

Choice C reason: Increased secretion of aldosterone is not a cause of hyponatremia, but rather a cause of hypokalemia. Aldosterone is a hormone that regulates the sodium and potassium levels in the body by increasing the reabsorption of sodium and the excretion of potassium in the kidneys. Increased secretion of aldosterone can cause hypokalemia, which is a condition where the potassium level in the blood is too low, which can affect the muscle and nerve function and cause symptoms such as weakness, cramps, or arrhythmias.

Choice D reason: Congestive heart failure (CHF) is a cause of hyponatremia, as it is a condition where the heart is unable to pump enough blood to meet the body's needs. This can lead to fluid retention and edema, which can dilute the sodium level in the blood and cause hyponatremia. CHF can also stimulate the release of antidiuretic hormone (ADH), which increases the reabsorption of water in the kidneys and further lowers the sodium level in the blood.