General Principles Flashcards
What is the definition of DM?
A syndrome with disordered metabolism and inappropriate hyperglycemia due to either a deficiency of insulin secretion or a combination of insulin resistance and inadequate insulin secretion to compensate
Discuss the epidemiology of DM
- >25 million diabetics in US with >90-95% being Type 2
- Genetic predisposition
- Significant morbidity and mortality
What are the four clinical classes of diabetes?
- Type 1
- Type 2
- Gestational
- Other specific types of DM (genetic defects in insulin secretion or action, pancreatic surgery or disease, endocrinopathies- Cushings, acromegaly, drugs, and diabetes associated with other syndromes)
Discuss the pathophysiology of T1DM
results from cellular-mediated autoimmune destruction of the beta (β) cells of the pancreas.
discuss presentation of T1DM in a child vs older adult
- Rate of destruction of B cells is rapid in infants and children and slower in adults
- Presentation in young- ketoacidosis
- Presentation in adults-longer sx prodrome and may be diagnosed on basis of hyperglycemia and positive autoantibodies
discuss how long it takes for a T1 diabetic to develop ketosis without insulin
8-16 hours
How long does it take for a T1 diabetic to develop ketoacidosis without insulin?
12-24 hours
Why is it important for tight blood glucose (BG) control early on in a T1 diabetic?
It has been shown to preserve the residual B cell function and prevent or delay later complications
What is LADA?
- Latent autoimmune diabetes in adults
- Characterized by mild-moderate hyperglycemia at presentation that often responds to noninsulin therapies that progresses over months to years to insulin dependency
- Will have 1 or more B cell specific autoantibodies and tend to require insulin sooner than those with Type 2
Discuss the pathophysiology of T2DM
Characterized by insulin resistance followed by reduced insulin secretion from B cells that are unable ti compensate for increased insulin requirements
Which races have a higher risk of developing T2DM than whites?
- African Americans
- Hispanics/Latinos
- Asian Indians
- Native Americans
- Pacific Islanders
- some groups of Asians
What are risk factors for developing T2DM?
- Obesity
- Family history of diabetes
- History of gestational diabetes or prediabetes
- HTN
- physical inactivity
- Race/ethnicity
What is gestational DM?
Any degree of glucose intolerance, with onset or diagnosis during pregnancy
What percentage of pregnant patients will go on to develop T2DM?
60% of women with GDM will develop T2DM in the ensuing 5-10 years and all remain at an increased risk for development of T2DM later in life
How is DM dx?
- Hemoglobin A1C > 6.5%
- Fasting plasma glucose >126mg/dL after an overnight fast (should be confirmed with repeat test)
- Sx of diabetes (polyuria, polydipsia, fatigue, weight loss) and a random plasma glucose level of >200mg/dL
- Oral glucose tolerance test that shows plasma glucose level of >200mg/dL at 2 hours after ingestion of 75g of glucose
What is the definition of prediabetes?
- Impaired fasting glucose: FPG >100mg/dL and <125mg/dL
- Impaired glucose intolerance: 2-hour glucose 140-199mg/dL after ingesting 75g glucose (OGTT)
- A1C: 5.7-6.4%
How do you council someone with prediabetes in terms of lifestyle changes?
- Balanced hypocaloric diet to achieve 7% weight loss in overweight patients
- Regular exercise of >150mins per week
List major goals of therapy for DM
- Alleviation of symptoms
- Achievement of glycemic, blood pressure, and lipid targets
- Prevention of acute and chronic complications
What are fasting/preprandial targets for DM?
Fasting/pre-prandial BS 70-130 mg/dL
What is the blood pressure target for diabetics?
<130/80mmHg
What is first line treatment for hypertension in diabetics?
ACE inhibitor (Lisinopril) or ARB (Losartan)
For patients not at goal with answer to the above question, what medication should you add for adjunct therapy if:
eGFR <30
Loop diuretic (Furosemide)
For patients not at goal with answer to the above question, what medication should you add for adjunct therapy if:
eGFR >30
Thiazide diuretic (HCTZ)
What is the role of aspirin in the treatment of DM?
- Diabetics have abnormal platelet function with increased incidence of small vessel thrombosis and atherosclerosis
- 2013 ADA: ASA for adult diabetics with >10% risk for cardiac event over 10 years
- Men >50 or women >60 with one or more major risk factors for CHD
- ASA for all adult diabetics with macrovascular disease (CHD, PVD, CVD) and older than 40 years
- Dose: 75-162 mg/daily
- Risks: PUD, gastritis, bleeding
- 2013 observational study of men/women with T@DM and no prior CVD: 4608 patients on ASA with 14,038 not on ASA- no benefits from ASA. Conclusion: more restrictive use of ASA in patients with T2DM and no CVD
How often should diabetics be checking their blood glucose?
- Patients with multiple daily insulin injections or insulin pumps: 3 or more times daily (can be done before meals and at bedtime or periodic testing 1-2 hours after eating to achieve postprandial glucose targets)
- Less frequent testing may be appropriate for those on noninsulin therapies
What is a hemoglobin A1c?
provides integrated measure of BG values over preceding 2-3 months
Why is A1c checked every 3 mo?
A1c checks the amount of glucose bound to hemoglobin in the red blood cells – RBC only live for 3 months
How often do you monitor A1cs?
Obtained every 3 months in patients not at goal or when either diabetes therapy or clinical conditions changes
Twice yearly in well-controlled patients
When an A1c is higher than expected based off of pt’s glucose readings, what do you need to investigate?
Should be evaluated by diabetes educator to ensure meter accuracy, appropriate technique, and frequency of testing
When an A1c is lower than expected based off of a pt’s glucose readings, what do you need to investigate?
Blood loss, transfusion, hemolysis, and hemoglobin variants
How can a diabetic prevent ketoacidosis?
- Checking ketones in fingerstick blood sample by measuring B-hydroxybutyrate with the handheld glucose/ketone meter, Precision Xtra.
- Urine ketones can also be qualitatively identified using Ketostix or Acetest tablets
When should pts with T1DM check for ketoacidosis?
- Febrile illness
- Persistent elevation of glucose (>300mg/dL) or signs of impending DKA
What are signs of impending DKA?
Nausea, vomiting, abdominal pain
What dietary recommendations would you make for a diabetic?
Calories
1,000-1,500 kcal/d for women and 1,200-1,800kcal/d for men depending on activity level and starting body weight
What dietary recommendations would you make for a diabetic?
Carbs/proteins/fats
- Carbs: 45-65%
- Protein: 10-30%
- Total fat: <30% (<7% saturated fat)
What dietary recommendations would you make for a diabetic?
Cholesterol
<300mg/d
What dietary recommendations would you make for a diabetic?
h/o CKD
protein restriction of 0.8g/kg/d along with additional restrictions of potassium and phosphorus containing foods if severe CKD
What would you recommend for carbohydrate goals for a diabetic?
“carb counting” for patients on intensified insulin therapy who adjust insulin doses based on carb content of meals/snacks
When should a diabetic be hospitalized?
- DKA characterized by PBG >250mg/dL in association with an artierial pH <7.3 or serum bicarb level <15meq/L and moderate ketanemia or ketonuria
- Hyperosmolar nonketoic state includes marked hyperglycemia (>400mg/dL) and elevated serum osmolality (>315 mOsm/kg) often accompanied by impaired mental status)
- Hypoglycemia if induced sulfonylurea medication, is due to deliberate drug overdose, or results in coma, seizure, injury, or persistent neurologic change
- Newly diagnosed T1DM or newly recognized GDM even in the absence of ketoacidosis
- Patients with T2DM if initiation or change in insulin therapy unless hyperglycemia is severe and associates with mental status change or other organ dysfunction
What is the definition of DKA?
DKA characterized by:
- PBG >250mg/dL
- arterial pH <7.3
- or serum bicarb level <15meq/L and moderate ketanemia or ketonuria
What is the definition of hyperosmotic nonketotic state?
- marked hyperglycemia (>400mg/dL)
- elevated serum osmolality (>315 mOsm/kg) often accompanied by impaired mental status)
What are glucose targets for inpatients in critical care?
140-180 mg/dL with frequent monitoring recommended for scrupulous avoidance of hypoglycemia
What are glucose targets for inpatients in noncritical care?
140mg/dL fasting and premeal, <180 mg/dL post meal or on a random glucose check
What class of medication should be used in management of hyperglycemia in critical care settings?
Variable IV insulin infusion
How often do you check glucose levels in a critical care setting?
hourly at bedside
how do you prevent hypoglycemia and ketosis in a critical care setting?
IV infusion of a dextrose-containing solution or other caloric source should be provided to prevent
Which type of fluid works best for patients with fluid restriction in a critical care setting?
10% dextrose in water (D10W) infused at a rate of 10-25mL/hr to provide steady, consistent source of calories
What class of mediciation should be used management of hyperglycemia in noncritical care settings?
Insulin
How often do you check glucose levels in a noncritical care setting?
On admission and 4x daily in hyperglycemia patients, especially treated with insulin
How do you dose insulin and what type of insulin therapy works best in a noncritical care setting?
- Patients native to insulin: starting dose of basal insulin should equal 0.2U/kg or 0.1U/lb
- If BG level >200mg/dL, adding premeal insulin is appropriate and the dose should be 0.2U/kg divided by 3 meals
- Patients with T1DM should continue home insulin doses and may continue use of an insulin pump if hospital policy is in place to do so
- Insulin doses in patients with T2DM should be reduced by 20-50% on admission
How do you manage hypoglycemia in noncritical care setting?
- Treated promptly with oral or IV glucose and the capillary BG should be repeated every 10 mins until >100mg/dL stable
- Reevaluation of scheduled doses and assessment of risk factors for hypoglycemia (declining renal function, hepatic impairment, poor intake) should be undertaken for any BG <70mg/dL
What is the A1c cutoff for elective surgery?
>8.5%
What labs do you need to check in a diabetic prior to surgery?
- Glucose
- Acid-base
- Electrolyte (K, Mg, Phosphate)
- Fluid status
What are perioperative glucose targets?
108-180mg/dL (checked hourly in persons with diabetes who gave taken insulin or who require insulin perioperatively)
For outpatient procedures, how should a diabetic manage their insulin?
Continue basal insulin doses and resume bolus doses with corrections as soon as possible postoperatively
For emergency or major elective surgery, how is glucose in a diabetic on insulin managed?
- Variable IV insulin infusion, supplemented with glucose and potassium as needed to achieve target BG levels
- Hourly glucose measurements are mandatory to adjust insulin and glucose infusions
- K+ should be monitored at least every 2 hours and replaced aggressively as required
