DM

Diabetes melitus

Glucose metabolismInsulin release -cells, Islets of Langerhans in pancreasStimulated by rising blood glucoseInhibited by low blood glucoseInsulin actionsIncreases metabolism of glucoseLowers blood concentration of glucoseEnhances carbohydrate metabolism (energy)Spares fat and protein metabolism

Blood glucose regulationGlucagon-cells, Islets of LangerhansPrevents hypoglycemiaStimulates the release of glucose from the liver into the bloodstream

InsulinMust be used in type 1 diabetesMay be used in type 2 diabetes when oral agents are not effective enoughInsulin use does not mean insulin dependence

Insulin onset & peak of action

Types of insulinClassified byDuration of actionSpecies of origin

Insulin characteristicsNovolin insulin profilesHumulin insulin profiles

Insulin dosage regimensHighly individualizedInsulin needsDiet & exercisePatient motivation & ability to complyOnce a dayTwice a dayIntermediate or long-acting with regular & sliding scale

Insulin dosage regimensIntensive insulin therapyMultiple daily measurements and injectionsGoal: near normalization of blood glucose without hypoglycemia50-75% reduction in complications (retinopathy, nephropathy, neuropathy)Insulin pump administration

Monitoring of insulin regimen effectivenessShort term: Fingerstick Blood glucose measurementQID & prn with changes & intensive therapy Log results & insulin usageGoal: 80-120 (tight control)Long term: Hemoglobin A1C Glycosylated hemoglobinGoal: < 7.0 (normal 4-6 in nondiabetics)Frequency of Hypoglycemia episodesOften occurs in middle of night

Adverse reactionsHypoglycemiaCauses:Too much insulinNot enough foodExcessive physical activityMost likely to occur with insulin peakMost common with tight glucose control

Adverse reactionsAllergic reactionsSoreness, erythema, induration at injection siteSystemic rash & itchingAllergic reactions are most common with animal insulin, especially beef

Adverse reactionsLipodystrophiesLipoatrophySaucer-like depressions in skin surfaceFat seems to have melted awayLipohypertrophySpongy (fatty) area at injection siteInsulin stimulates fat synthesisSite rotation used to prevent problems

Special SituationsSick daysHospitalizationMay need insulin drip & frequent checksDiet restrictions (NPO, etc)

Drugs for Type 2 diabetes

Sites of action for oral hypoglycemic drugs

SulfonylureasGlipizide (Glucotrol, Glucotrol XL)Glyburide (Diabeta)Glimepiride (Amaryl)Used in type 2 onlyActionStimulates pancreatic -cell release of insulin

Sulfonylureas: adverse reactionsHypoglycemia:More common with long-acting agents, in elderly & in renal failureLong-acting Glipizide is less likely to cause hypoglycemia

Sulfonylureas: administrationShort-acting sulfonylureas are often given 30 minutes before meal to promote normalization of blood glucoseLong-acting sulfonylureas may be given with meals

BiguanidesMetformin (Glucophage)Action: decreases hepatic production of glucose, decreases intestinal glucose absorption, increases insulin sensitivityMay be used in combination with sulfonylureas

Biguanides: MetforminAdverse effectsCommon: Nausea, vomiting, diarrhea, bloating (resolve with therapy)Serious: Lactic acidosis Contraindicated in renal, hepatic & cardiac dysfunctionMust be stopped 24-48 hrs prior to procedure with IV contrast (i.e. angiogram)

Thiazolidinediones: glitazonestroglitazone (Rezulin)rosiglitazone (Avandia) newpioglitazone hydrochloride (Actos) new

Thiazolidinediones: glitazonesAction:Improves target cell response to insulinDecreases hepatic glucose outputDoes Not stimulate insulin secretionAction on pre-existing presence of insulinUsed as adjunct to diet and exercise in type 2May be added to sulfonylurea

Thiazolidinediones: glitazonesDoes not cause hypoglycemia May increase fertility in womenPatient counseling about contraception Should not be used in type 1May cause liver damage 1/57,000 transplant or deathMonitor liver function

Alpha-glucosidase Inhibitors(Starch blockers)acarbose (Precose)miglitol (Glyset)

ActionsSlows carbohydrate digestion & glucose absorptionAdministrationTid, before each meal

Alpha-glucosidase Inhibitors

Adverse effects: think GIAbdominal discomfort, diarrhea, flatulenceWeight lossBeneficial in obese patientsIncreased liver function tests

Meglitinidesrepaglinide(Prandin)Action: stumulates pancreatic insulin secretionUsed either alone or with metforminRapid onset, duration 4 hoursTake prior to each mealPrevents insulin peak after mealsAllows for irregular meal patternAdverse reaction: hypoglycemia

Treatment of hypoglycemic episodes15 grams of fast-acting carbohydrate4-6 oz fruit juice1/2 cup regular pop2-3 graham cracker squaresGlucagon IV or SCOnset: 5-20 minutes, peak 30 minutesDextrose 50% IV

Nursing ImplicationsPatient educationBlood glucose monitoringDietSkin care