Diabetes mellitus, more commonly known as diabetes, is a chronic disease marked by increases in blood glucose and an inability to make or properly use insulin.1 The most common types of diabetes are type 1 diabetes, in which the body does not make insulin at all; type 2 diabetes, in which the body does not make or use insulin well; and gestational diabetes, which develops during pregnancy and increases the mother’s chances of developing type 2 later in life.1 Type 2 diabetes is the most common type of diabetes and, unlike type 1 diabetes, it usually develops in adulthood.1 The causes of type 2 diabetes remain relatively unclear, though scientists posit that genetic and environmental factors—including being overweight—can contribute to insulin resistance in the disease.2 After many years of having diabetes and/or failing to adequately control blood sugar, complications such as cardiovascular disease, nerve damage (neuropathy), kidney damage (nephropathy), eye damage (retinopathy), foot damage, skin conditions, hearing impairment, Alzheimer’s disease and depression can arise.2 These complications can affect the medical management of a patient with diabetes, especially with regards to surgical decisions.3 Anesthesia specialists in particular must take caution when attending to patients with diabetes before, during and after surgery.
One of the responsibilities of the anesthesia practitioner is to be aware of the potential surgery-related risks for patients with diabetes. For one, hyperglycemia (i.e., high blood sugar that is present in diabetes) can cause increased surgical site infection, thromboembolism (blood vessel obstruction) and myocardial infarction (heart attack).4 Some studies have found that glucose fluctuations and hypoglycemia (low blood sugar) throughout surgery can actually be more harmful to the body than hyperglycemia.5 Additionally, variability in heart rate and cardiac rhythm, as well as hypotensive reactions, can occur for a diabetic patient during surgery.6 Other practical factors in diabetes, such as limited mobility of the cervical spine and jaw joint, may make it more difficult for anesthesia specialists to perform laryngoscopy and thus intubation for provision of anesthesia.7 Clearly, patients with diabetes face risks above and beyond the standard risks that come with anesthesia administration.
Anesthesiologists can prepare patients for surgery with several preoperative strategies. For example, Duggan et al. found that pre-procedure carbohydrate loading may counteract the insulin resistance that occurs due to stress and starvation during surgery.8 Other researchers suggest preoperative evaluation of diseases that are comorbid with diabetes in order to prevent complications during and after surgery.6,9 Conditions that may require treatment before surgery include cardiovascular disease, neuropathy, joint collagen tissue and immune deficiency.9 In order to anticipate atypical hemodynamics and blood pressure instability in diabetic patients with neuropathy, an anesthesiologist may test the patient’s cardiovascular reflexes, such as heart rate variability during deep breathing, changes in blood pressure from lying to standing and sustained hand grip.6 Given the many conditions associated with diabetes, anesthesia practitioners may need to prepare a diabetic patient for surgery with various evaluations and treatments.
During surgery, the anesthesia provider is responsible for monitoring and controlling the vital signs of all patients. For patients with diabetes, this duty becomes more complicated. For one, the anesthesia practitioner must control the patient’s blood glucose to avoid the deleterious effects of glycemic variability (e.g., increased risk of cardiovascular events).10 A study by Smith et al. found that adequate glycemic control could be achieved in most diabetic patients undergoing cardiac surgery using a modified insulin clamp technique.11 Other strategies employed by the anesthesia practitioner during surgery include low impact practices to avoid glucose fluctuations, such as provision of medication and insulin.5 Considering the limited jaw mobility of diabetic patients, anesthesia providers may also need to focus on airway management.7 Finally, for pregnant patients with diabetes, the anesthesiology practitioner should carefully select anesthetic drugs and collaborate with the obstetrician throughout surgery.12
After a procedure, an anesthesia provider’s role does not become any less important. An anesthesiologist must monitor the diabetic patient’s glucose levels and aim to limit hyperglycemia, which may decrease the length of stay, reduce hospital complications and speed up wound healing.8 The anesthesiologist’s postoperative management of a patient with diabetes should emphasize rapid recovery,5 which often includes an strict insulin regimen.8
Overall, the anesthesiology practitioner is vital before, during and after surgery for a diabetic patient. Preoperative treatment and evaluation, intraoperative monitoring and provision of insulin and postoperative glycemic control are key roles of the anesthesia provider. Future studies should focus on personalizing anesthetic treatment based on a patient’s diabetes-related complications to make perioperative processes as seamless as possible.
1. National Institute of Diabetes and Digestive and Kidney Diseases. What is Diabetes? Health Information 2019; https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes.
2. Mayo Clinic. Diabetes. Diseases & Conditions 2019; https://www.mayoclinic.org/diseases-conditions/diabetes/symptoms-causes/syc-20371444.
3. Dagogo-Jack S, Alberti KGMM. Management of Diabetes Mellitus in Surgical Patients. Diabetes Spectrum. 2002;15(1):44–48.
4. Brown R, Siddiqui U, Paul J. A survey: Perioperative diabetes medications and glucose control—time to re-examine management? Canadian Journal of Anesthesia/Journal canadien d’anesthésie. 2019;66(5):621–622.
5. Vann MA. Perioperative management of ambulatory surgical patients with diabetes mellitus. Current Opinion in Anesthesiology. 2009;22(6):718–724.
6. Knüttgen D, Weidemann D, Doehn M. Diabetic autonomic neuropathy: Abnormal cardiovascular reactions under general anesthesia. Klinische Wochenschrift. 1990;68(23):1168–1172.
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8. Duggan EW, Carlson K, Umpierrez GE. Perioperative Hyperglycemia Management: An Update. Anesthesiology. 2017;126(3):547–560.
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10. Suh S, Kim JH. Glycemic Variability: How Do We Measure It and Why Is It Important? Diabetes & Metabolism Journal. 2015;39(4):273–282.
11. Smith CE, Styn NR, Kalhan S, et al. Intraoperative glucose control in diabetic and nondiabetic patients during cardiac surgery. Journal of Cardiothoracic and Vascular Anesthesia. 2005;19(2):201–208.
12. Ramanathan J, Ivester T. Diabetes mellitus in pregnancy: Pathophysiology and obstetric and anesthetic management. Seminars in Anesthesia, Perioperative Medicine and Pain. 2002;21(1):26–34.