Unexpected hypopotassemia after multiple blood transfusions during an operation

Area of Science:

• Anesthesiology
• Nephrology
• Critical Care Medicine

Background:

• Transfusion of donor blood is common in major surgeries.
• Postoperative electrolyte balance, particularly serum potassium, is crucial for patient outcomes.
• The relationship between transfusion volume and potassium shifts requires further elucidation.

Purpose of the Study:

• To investigate the influence of transfused donor blood volume on postoperative serum potassium levels.
• To identify the incidence of hyperkalemia and hypokalemia following major surgery and blood transfusion.
• To assess the impact of metabolic acidosis and hyperglycemia on potassium balance.

Main Methods:

• Study included 226 patients undergoing major surgery.
• Exclusion criteria: preoperative hypokalemia, impaired renal function, potassium-lowering medications.
• Laboratory analyses: complete blood count, electrolytes, creatinine, BUN, glucose, acid-base balance, urinalysis.

Main Results:

• No direct relationship found between transfused blood volume and serum potassium shifts.
• Hyperkalemia was not observed.
• Unexpected hypokalemia occurred in 50 patients (22.1%).
• Metabolic acidosis (57%) and hyperglycemia (48%) did not significantly influence potassium balance.

Conclusions:

• Major surgery and blood transfusion can lead to unexpected hypokalemia.
• Hypokalemia poses potential complications and requires proactive management.
• Caution is advised when administering calcium, insulin, bicarbonate, and digitalis to patients with altered potassium levels post-transfusion.