INS and Hyperkalemia: Alternatively, 20 units of short acting insulin may be given as a continuous intravenous infusion over 60 minutes in patients with severe hyperkalemia (i.e., serum K+ concentration > 6.5 mmol/L) and those with marked EKG changes related to hyperkalemia (e.g., prolonged PR interval, wide QRS complex) as an alternative to 10 units of short acting insulin.