Interactive diabetes case 12: Perioperative management of a 67-year-old patient with type 2 diabetes who undergoes coronary artery bypass surgery – A3

ANSWER — Correct.

You see the patient on rounds early the next morning. The patient has had a difficult night. He was intermittently hypotensive and is receiving pressors, including levarterenol. The glucose level rose transiently to values as high as 377 mg/dL (20.9 mmol/L) when hypotension developed but was subsequently maintained close to the target range, with glucose values since midnight in the 79 to 143 mg/dL (4.4 to 7.9 mmol/L) range. The most recent glucose value is 117 mg/dL (6.5 mmol/L). The patient's insulin requirement has varied markedly. When he became hypotensive, the requirement rose from 3 units an hour to 7 units an hour. It then fell to 4 units an hour as the blood pressure returned to normal.

Over the next two days, the patient improves. He is gradually weaned from pressors, and the insulin requirement falls concomitantly. The glucose values remain in or close to the target range. The insulin infusion rate has been stable in the last 12 hours in the range of 2 units an hour.

You see the patient on morning rounds. The intensive care unit (ICU) team plans to transfer the patient to the postoperative cardiac surgical floor at approximately 8 PM when a bed is available and to stop the intravenous insulin infusion at that time.

You congratulate the ICU nurses and clinicians on their successful implementation of the insulin infusion protocol. You note that the glycated hemoglobin (A1C) values indicate that the patient's glycemia was not adequately managed before admission on maximal doses of glipizide and metformin, and you conclude that the patient will need a basal subcutaneous insulin regimen at the time of discharge from the hospital. You decide to initiate this in the ICU to facilitate determination of the dose before discharge from the hospital.

What do you recommend now?

●You order glargine insulin 10 units at 10 PM and a sliding scale of aspart every six hours, starting with 2 units for a blood glucose of 201 to 250 mg/dL (11.2 to 13.9 mmol/L) and advancing by 2-unit increments for every 50 mg/dL (2.8 mmol/L) increment of blood glucose to 8 units of aspart for a blood glucose of 351 to 400 mg/dL (19.5 to 22.2 mmol/L). (See "Interactive diabetes case 12: Perioperative management of a 67-year-old patient with type 2 diabetes who undergoes coronary artery bypass surgery – B1".)

●You order glargine insulin 10 units at 5 PM to allow overlap between the intravenous insulin infusion and the onset of action of the glargine insulin. You also order a sliding scale of aspart every six hours, starting with 2 units for a blood glucose of 201 to 250 mg/dL (11.2 to 13.9 mmol/L) and advancing by 2-unit increments for every 50 mg/dL (2.8 mmol/L) increment of blood glucose to 8 units of aspart for a blood glucose of 351 to 400 mg/dL (19.5 to 22.2 mmol/L). (See "Interactive diabetes case 12: Perioperative management of a 67-year-old patient with type 2 diabetes who undergoes coronary artery bypass surgery – B2".)

●You order glargine insulin 38 units at 5 PM to allow overlap between the intravenous insulin infusion and the onset of action of the glargine insulin. You also order a sliding scale of aspart every six hours, starting with 2 units for a blood glucose of 201 to 250 mg/dL (11.2 to 13.9 mmol/L) and advancing by 2-unit increments for every 50 mg/dL (2.8 mmol/L) increment of blood glucose to 8 units of aspart for a blood glucose of 351 to 400 mg/dL (19.5 to 22.2 mmol/L). (See "Interactive diabetes case 12: Perioperative management of a 67-year-old patient with type 2 diabetes who undergoes coronary artery bypass surgery – B3".)

●You order glargine insulin 38 units at 5 PM to allow overlap between the intravenous insulin infusion and the onset of action of the glargine insulin. You also order correction doses of aspart every six hours, starting with 4 units for a blood glucose of 141 to 180 mg/dL (7.8 to 10 mmol/L) and adding 2 units at blood glucose increments of 40 mg/dL (2.2 mmol/L; eg, 6 units for a glucose of 181 to 220 mg/dL [10.1 to 12.2 mmol/L]). You anticipate that caloric intake will be limited for the first few days after cardiac surgery and do not order prandial doses of insulin at this time. (See "Interactive diabetes case 12: Perioperative management of a 67-year-old patient with type 2 diabetes who undergoes coronary artery bypass surgery – B4".)