Type 1 DM Etiology & Pathology

Diabetes MellitusSignificance

Roughly 7 million people have been dx with DM.

7th leading underlying cause of death in the U.S.

Leading cause of blindness in adults 20-70 yo.

It accounts for:30% of new cases of ESRD50-60% of adult deaths from CAD

40-50% of non traumatic amputations for foot/ankle ulcers.

Diabetes MellitusDefinition and Classification

Is a chronic disorder of altered CHO, fat & Protein metabolism caused either by:

A relative lack of insulin (type 1).Or the inability to respond to insulin (type

11).

Is characterized by persistent hyperglycemia, impaired leukocyte activity & long-term vascular & neurological degeneration

Diabetes MellitusRisk Factors

Familial hx of DM

African-American, Hispanic, or Native American descent.

Obesity

Morbid OB hx. Or hx of delivering infants weighing > 9 lbs.

Type 1 DM Etiology & Pathology

Formerly known as insulin-dependent DM or juvenile diabetes

An autoimmune ds in which autoantibodies are directed against the islet cells

Once the islet cells are destroyed, the pancreas can no longer produce insulin

On order to control glucose levels, daily exogenous insulin is required.

Type 11 DM Etiology & Pathology

Formerly known as non-insulin dependent DM

Although the amount of endogenous insulin produced may be WNL, the problem is that insulin cannot bind with cell receptor sites to promote transport of glucose into the cell.

Do not usually require exogenous insulin, but if they do, it is called insulin-requiring DM

Diabetes Mellitus Somogyi and Dawn phenomenon

Hypoglycemia usually at night followed by compensatory rebound hyperglycemia ( lasts 12 to 72 hours). Usually caused by too much insulin or an increase in insulin sensitivity. Can be stabilized by gradual lowering of insulin dose and increase in diet at the time of the hypoglycemic reaction.

Dawn phenomenon-BS normal until 3 am-begins to rise in early morning hours. Glucose released from liver in early A.M.- needs to be controlled.Altering time and dose of insulin (NPH or ultralente) by two or two units-stabilizes the pt.

Diabetes Mellitus Signs & Symptoms

The “ 3 P’s” (less severe in type 11 DM)> Polyuria

> Polydipsia> Polyphagia

FatiguePruitusKetosis (more common in Type 1 DM)Blurred vision (retinopathy)Tingling, numbness, or pain in the extremities (neuropathy).

Diabetes Mellitus Diagnosis

Symptoms of DM plus casual plasma Glu concentration of 200 mg/dl or higher OR

Fasting plasma Glu level of 126 mg/dl or higher or

2-hr plasma Glu level of 200 mg/dl or greater during an oral glucose tolerance test.

Diabetes Mellitus Treatments

Diet – 60% CHO, 20% fats, 20% protein

Exercise

Insulin therapy: goal is to mimic the pattern of normal insulin secretion.Rapid-acting (e.g. Humulin R (or regular)Intermediate-acting (e.g. NPH)Long-acting (e.g. Humulin U)Mixtures (e.g. Humulin 70/30)

Acute Complications of DM Diabetic Ketoacidosis (DKA)

Usually occurs in type 1 DMDevelops when both insulin deficiency & excess stress hormones occurHyperglycemia, acidosis, & ketosis must all be present for dxBlood Glu levels between 300-800 mg/dlKetones produced from lipolysisBlood pH < 7.35Serum osmolality < 350 mOsm/kgThis is considered a medical emergency; if untreated coma & death can occur.

Acute Complications of DM Diabetic Ketoacidosis (DKA) treament

Major goals include correcting the following:Insulin therapy

Reestablish fluid balanceReplace electrolyte loss

Patient family teaching

Acute Complications of DM Hyperosmolar Nonacidotic Diabetic (HNAD)

Usually occurs in type 11 DM

Blood Glu levels between 600-1200 mg/dl

No ketones produced

Serum osmolality > 350 mOsm/kg

Blood pH WNL

Because the onset is gradual, condition can be missed or mis-dx for several weeks.

Acute Complications of DM Hyperosmolar Nonacidotic Diabetic (HNAD

Signs & Symptoms:> Neurologic abnormalities (confusion, seizures,

hemiparesis, aphasis, central hyperthermia). > Hyperglycemia, hyperosmolality & osmotic

diuresis.> Hypotension

Primary Goals are to: > Reestablish fluid balance > Replace electrolytes loss > Insulin therapy

> Patient/family teaching

Acute Complications of DM Hypoglycemia

Also called insulin shock or insulin reactionOccurs when blood Glu levels fall below 50 mh/dlSigns & symptoms:

> Range from mild to severe tremors, diaphoresis, confusion, blurred vision, drowsiness, convulsions.Treatment:

> Rapid administration of glucose.

Chronic Complications of DM Microvascular

Retinopathy- progressive impairment of retinal circulation that eventually causes vitreous hemorrhage with vision loss.

Assessment:> Impaired vision.

Implementation:Assist in ways to maintain independence &

self-esteem.Instruct in actions that prevent or reduce

complications:stable Blood glucose levels.

Chronic Complications of DM Microvascular

Neuropathy- general deterioration that affects the peripheral and autonomic nervous systems.

Assessment: Peripheral neuropathy:

> Pain in the legs> Aching and burning sensations in lower ext.

Alterations in bowel & bladder function-constipation, diarrhea, nocturnal fecal incontinence,infrequent voiding, weak stream, dribbling, signs of UTI.Autonomic nervous system- sexual dysfunction, orthostatic hypotension, pupillary changes

Chronic Complications of DM Microvascular

Circulatory abnormalities- skin breakdown and signs of infection, thick toenails: suggestive of circulatory impairment, athlete’s feet, thin, shiny, atropic skin, weak peripheral pulses.Implementation:

Assist to deal with pain- encourage walking for exercise, provide foot cradle when in bed.

Assist to deal with bladder-bowel problems-provide privacy,encourage fluids, administer drugs for diarrhea.

Allow to ventilate abt. sexual impotence Prevent moisture from accumulation bet. toes Instruct in well-fitting shoes. Don’t go barefoot

Chronic Complications of DM Microvascular

Nepropathy-intercapillary glomerulosclerosis- Kimmelstiel-Wilson syndrome-pathologic changes in the kdney that reduce kidney function-due to chronic DM.

Assessment:> proteinuria, azotemia,frequent UTI,

neurogenic bladder.

> BUN, creatinine elevated> Thirst and fatigue

Chronic Complications of DM Microvascular

Implementation:Administer meds. To prevent UTI.Instruct to keep BS levels WNL.Maintain adequate fluid intakeInstruct in 20 to 40 grams protein dietRestrict sodium and potassium in dietPrepare for dialysis therapy if appropriate.Male erectile dysfunction (ED)- inability to maintain an erection. Caused by neuropathy,vascular disease, psychological disorders. Autonomic neuropathy are responsible for persistent ED.

Chronic Complications of DM Macrovascular

Cardiovascular- Hypertension-the goal to reduce BP less than 130/80 mm hg.

Lifestyle modification- weight loss, Na restriction, exercise. Ace inhibitors- Calcium channel blockers.Beta blockers- mask hypoglycemia-worsening of insulin resistance.

Atherosclerosis- elevated low-density lipoprotein,elevated triglycerides.

PVD- Diabetic Foot- neuropathy- ischemia-sepsis.