Case 26 Flashcards
Describe the pathophysiology of type 1 and type 2 diabetes mellitus.
- What are the end-organ effects of diabetes mellitus, and how do they affect the perioperative course?
Autonomic Dysfunction
Gastroparesis
Fluid And Electrolyte Disturbances
Cardiovascular Risk
- Discuss the oral medications and insulin preparations available to treat diabetes mellitus and how they should be managed perioperatively.
- What impact does hyperglycemia have on perioperative morbidity and mortality?
○ Hyperglycemia in the perioperative period is associated with increased risk of infection secondary to impaired leukocyte function—specifically, impaired chemotaxis, phagocytosis, and intracellular bacterial killing.
○ It is also associated with impaired collagen synthesis and decreased nitric oxide production, reducing local perfusion and delaying wound healing.
○ Vascular reactivity can be altered with increased levels of angiotensin II and enhanced systemic vascular resistance.
○ Elevated glucose levels are also associated with renal injury, pulmonary complications, myocardial infarction, cerebrovascular insult, longer hospital and intensive care unit (ICU) stays, and increased mortality.
○ These adverse outcomes are found to be more prevalent in patients without a previous diagnosis of DM who develop hyperglycemia perioperatively than in patients with a known history of DM.
- What is “tight glucose control,” and what are its advantages and disadvantages?
Endocrinologists and American Diabetes Association, to target a blood glucose level of 140–180 mg/dL for most inpatients, while carefully monitoring for and treating hypoglycemia should it arise.
- Describe and contrast diabetic ketoacidosis and hyperglycemic hyperosmolar states.
- Outline the management of diabetic ketoacidosis and hyperglycemic hyperosmolar states.
- When should elective surgery be delayed because of hyperglycemia?
○ Before proceeding with elective surgery, it is prudent to evaluate patients with markedly elevated glucose (.300 mg/dL) for evidence of ketoacidosis with either blood chemistry or urine dipstick.
○ If significant acid-base or electrolyte disturbances exist, surgery should be postponed until the patient’s metabolic derangements have normalized.
○ There are no recommendations regarding an absolute glucose cutoff level above which elective surgery should be postponed if there are no other metabolic derangements. However, some institutions have policies in place to guide practitioners.
○ In the absence of an institutional policy, practitioners should base their decision on the urgency of the procedure, the risks of the procedure, and the ability to achieve better glucose control if surgery is postponed.
