A 62 year old man post bowel resection has low urine output and is becoming breathless. What is the SINGLE most appropriate immediate management for his condition?

In the scenario presented, the patient exhibits low urine output and breathlessness after bowel resection, which raises concern for possible hyperkalemia, a condition where there is an elevated level of potassium in the blood. Hyperkalemia can lead to serious complications, including cardiac issues, and can cause symptoms such as low urine output due to renal impairment.

The correct choice involves administering insulin along with glucose. This combination is known to be effective in managing hyperkalemia. Insulin facilitates the uptake of potassium into the cells, which helps to lower serum potassium levels quickly. The addition of glucose in this case is essential to prevent hypoglycemia caused by the insulin administration.

The 10 units of insulin will act to shift potassium into the cells and, coupled with the 50 ml of 50% glucose infusion, ensures that the patient's blood sugar remains stable during this treatment.

In this clinical context, other options do not provide the immediate and effective intervention needed for suspected hyperkalemia. For instance, administering calcium resonium is a method to exchange potassium for calcium in the gastrointestinal tract, but it may not act quickly enough to address acute hyperkalemia. Similarly, sodium bicarbonate may help in shifting potassium but is not the first-line treatment in this urgent