DM Flashcards
What are some hyperglycemia-producing hormones?
Glucagon, epinephrine, growth hormone, cortisol
What is the role of glucagon in the glucose counterregulatory system?
Stimulating glycogenolysis & gluconeogenesis, inhibiting glycolysis
What is the most common endocrine disease? What is the prevalence of this disease in adults?
Diabetes mellitus. 1 in 10
What leads to microvascular and macrovascular complications in diabetes mellitus?
Increased circulating glucose levels
What causes Type 1a diabetes?
T-cell-mediated autoimmune destruction of β cells
What characterizes Type 1b diabetes?
Rare disease of absolute insulin deficiency
What causes Type 2 diabetes?
Defects in insulin receptors and post-receptor intracellular signaling pathways
What age is Type I diabetes usually diagnosed? What percentage of all DM cases does Type 1 Diabetes account for?
Before age 40. 5-10%
What is the autoimmune cause of Type 1a diabetes?
Exact cause unknown
How long is the pre-clinical period of B-cell antigen production before symptoms appear? How much B cell function is lost before hyperglycemia sets in?
9-13 yrs
80-90%
What symptoms are associated with hyperglycemia in Type 1 Diabetes?
Fatigue, weight loss, polyuria, polydipsia, blurry vision, hypovolemia, ketoacidosis
What percentage of diabetes mellitus cases does Type 2 Diabetes account for? How long may Type 2 Diabetes normally be present before diagnosis?
> 90%
4-7 years
What is a concerning trend regarding Type 2 Diabetes in recent years?
Increasingly seen in younger patients and children
What happens in the initial stages of Type 2 Diabetes? What occurs as Type 2 Diabetes progresses?
Insensitivity to insulin on peripheral tissues leads to increased pancreatic insulin secretion
Pancreatic function decreases and insulin levels become inadequate
What are the 3 main abnormalities seen in Type 2 Diabetes?
Increased hepatic glucose release, impaired insulin secretion, insufficient glucose uptake in peripheral tissues
What is type 2 diabetes characterized by?
Insulin resistance in skeletal muscle, adipose & liver
What are the causes of insulin resistance in type 2 diabetes?
Abnormal insulin molecules, Circulating insulin antagonists, Insulin receptor defects
What are acquired and contributing factors to type 2 diabetes?
Obesity and sedentary lifestyle
How can type 2 diabetes be diagnosed?
Fasting blood glucose, HbA1c
What is the preferred initial drug treatment for DM2?
Metformin
How does Metformin work in the body?
Enhances glucose transport
What are the potential side effects of Sulfonylureas?
Hypoglycemia, weight gain, cardiac effects
When is insulin necessary in diabetes mellitus cases?
All DM1 cases and 30% DM2 cases
What type of insulin provides glucose control at mealtimes?
Rapid acting (Lispro, Aspart)
Which type of insulin is considered basal/intermediate acting?
NPH, Lente
What leads to ‘hypoglycemia unawareness’?
Repetitive hypoglycemic episodes
What can neuroglycopenia result in?
Fatigue, confusion, h/a, seizures, coma
How should hypoglycemia be treated?
PO or IV glucose
What is Diabetic Ketoacidosis? What type of diabetes is it most commonly found in?
Complication of decompensated DM.
DM1
What is the mortality rate associated with Diabetic Ketoacidosis?
1-2%
What can trigger DKA in DM1 patients?
Infection/illness
How does high glucose levels contribute to DKA?
Exceeds renal reabsorption threshold
What metabolic processes lead to liver overproduction of ketoacids in DKA?
Tight coupling of gluconeogenesis & ketogenesis
What is the loading dose of insulin for DKA treatment? The low dose infusion rate of insulin for DKA treatment?
0.1u/kg Regular
Low Dose 0.1u/kg/hr
What electrolytes should be supplemented in DKA treatment?
k+, phos, mag, sodium
Why is it important to correct glucose and sodium levels simultaneously in DKA treatment?
Avoid cerebral edema
What is Hyperglycemic Hyperosmolar Syndrome characterized by? What age group does Hyperglycemic Hyperosmolar Syndrome normally occur in?
Severe hyperglycemia, hyperosmolarity & dehydration
DM2 >60 y/o
How does Hyperglycemic Hyperosmolar Syndrome evolve?
Over days to weeks with persistent glucosuric diuresis
What occurs when the glucose load exceeds maximum renal glucose absorption?
Mass solute diuresis
What are some symptoms of Hyperglycemic Hyperosmolar Syndrome?
Polyuria, polydipsia, hypovolemia, HoTN, tachycardia, organ hypoperfusion
What can hyperosmolarity lead to in Hyperglycemic Hyperosmolar Syndrome?
Coma
How does the acidosis in Hyperglycemic Hyperosmolar Syndrome compare to DKA?
Pts have some degree of acidosis, but not as severe as DKA
What is the treatment for Hyperglycemic Hyperosmolar Syndrome?
Fluid resuscitation, insulin bolus + infusion, electrolytes
What is the mortality rate of Hyperglycemic Hyperosmolar Syndrome?
10-20%
What is peripheral neuropathy? Where are the initial symptoms of peripheral neuropathy seen?
Distal symmetric sensorimotor polyneuropathy
Starts in toes/feet
How does peripheral neuropathy progress?
Progresses proximally
What are the effects of losing large sensory and motor fibers in peripheral neuropathy?
Decreased light touch & proprioception
How does the loss of small nerve fibers impact patients with peripheral neuropathy?
Neuropathic pain
What can lead to the development of ulcers in peripheral neuropathy?
Unnoticed injuries
How can peripheral neuropathy lead to significant morbidity?
Recurrent infections & amputation wounds
What are some treatments for peripheral neuropathy?
Optimal glucose control, NSAIDs, antidepressants, anticonvulsants
What is retinopathy characterized by?
Microvascular changes
What visual impairments can result from retinopathy?
Color loss to blindness
How can the progression of retinopathy be reduced?
Glycemic & BP control
What is autonomic neuropathy and what parts of the body can it affect?
Caused by damaged vasoconstrictor fibers, impaired baroreceptors, ineffective cardiovascular activity
What are some cardiovascular symptoms of autonomic neuropathy?
Resting tachycardia, loss of HR variability, progresses to ortho-HoTN & dysrhythmias
What are some gastrointestinal symptoms of autonomic neuropathy?
N/V, early satiety, bloating, epigastric pain
How can gastrointestinal symptoms of autonomic neuropathy be managed?
Glucose control, small meals, prokinetics
What systems should be emphasized in the preoperative evaluation for diabetes mellitus?
Cardiovascular, renal, neurologic, musculoskeletal
Why is silent ischemia possible in diabetic patients with autonomic neuropathy?
Autonomic neuropathy predisposes to ischemia
When should a stress test be considered in diabetic patients?
Multiple cardiac risk factors, poor exercise tolerance
How should hydration status be managed in diabetic patients preoperatively?
Meticulous attention, avoid nephrotoxins, preserve renal blood flow
What is a potential concern related to autonomic neuropathy in the perioperative period?
Dysrhythmia, hypotension risk
How can gastroparesis impact diabetic patients perioperatively?
Increased aspiration risk
What should be done with oral hypoglycemic and noninsulin injectable drugs preoperatively?
Hold them
What is an insulinoma?
Rare pancreatic tumor secreting insulin
What demographic does insulinoma present more often in?
Twice as much in women, in 50s-60s
What is the diagnostic criteria for insulinoma based on?
Whipple triad
What are the components of the Whipple triad for diagnosing insulinoma?
Hypoglycemia with fasting, Glucose <50 with symptoms, Symptoms relief with glucose
What is the preoperative treatment for insulinoma and its mechanism?
Diazoxide inhibits insulin release from B cells
What other treatments can be considered for insulinoma?
Verapamil, phenytoin, propranolol, glucocorticoids, octreotide
Is surgery curative for insulinoma?
Yes
What may occur during intra-op for insulinoma surgery?
Hypoglycemia then hyperglycemia
Why is tight glycemic control paramount in insulinoma management?
To manage postoperative glycemic fluctuations
