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Recommendations for Care of the Surgical Patient who has Diabetes Mellitus Part 2

By Olivia Marsh MS

There are two common pathways on how your patient will arrive to the preoperative area on the day of surgery. Patient A arrives for their elective procedure, a ventral hernia repair, scheduled for 45 minutes in the operating room (OR). With enhanced optimization from their endocrinologist and surgeon, the patient’s A1C, or glycated hemoglobin, is less than 7%. This indicates an average blood glucose level of 154 mg/dL (8.6 mmol/L). Optimizing preoperative glucose management has been correlated with improved outcomes, decreasing the risk of infection and rates of mortality and morbidity (Engleman et al., 2019). Also, this patient followed instructions given during the PAT phone call and they have withheld their metformin and had a carbohydrate rich, clear liquid drink 2 hours prior to arrival. Their blood sugar upon admission to preop is 140 mg/dL (7.8 mmol/L). You proceed with preparations for surgery.

Conversely, patient B is being scheduled for an emergency appendectomy. Coming from the ED, this patient would not have the opportunity to prepare for surgery. This patient may have well controlled insulin dependent diabetes mellitus (IDDM) otherwise, but because of possible infection from a ruptured appendix, pain and general stress, their blood glucose level on arrival to preop is 220 mg/dL (12.2 mmol/L). As part of preparation for surgery you assess your patient for their last oral intake, last dose of rapid acting and long-acting insulin. You find that they have an insulin pump that is attached subcutaneously, and they are receiving a basal dose of insulin at a rate of 0.8 unit/hour. You know that per policy, the anesthesia team requires that the insulin pump be removed for surgery. You also know that this may change in the future as more studies come out to support continuous glucose monitoring systems with closed loop insulin pump therapy, but this has not been approved at your facility yet. You remove the insulin pump, secure the patient’s medical device by giving it to their family member at bedside and notify the anesthesia provider of the elevated blood glucose. You receive orders in the electronic medical record for an IV dose of regular insulin, which is administered, and hourly blood glucose monitoring.

Intraoperatively, the anesthesia provider will monitor these patients differently. Patient A is well controlled prior to surgery and has a relatively short procedure scheduled. The anesthesia provider will likely not have to address the blood glucose level at all. A blood glucose check on arrival to PACU will be expected. Patient B will have hourly blood glucose monitoring and treatment if the blood glucose remains over 180 mg/dL (10.0 mmol/L) and they are receiving IV insulin (ADA, 20201, S212). Fast acting insulin should not be dosed more frequently than every 2 hours as noted per Duggan et al. (2017, p 555). These case examples should help you start to think about previous patient experiences and plan for future encounters with patients who have diabetes. In Part 3 we will discuss monitoring and management in the Post Anesthesia Care Unit (PACU) and beyond with a brief intro to technology. Stay tuned!


American Diabetes Association (2021, January). Diabetes care in the hospital: Standards of medical care in diabetes-2021. Diabetes Care, 44 (Supplement 1) S211-S220.