Renal Disorders Part 2

Renal Disorders Part 2

Chronic Kidney Disease (CKD)

• Progressive, irreversible loss of kidney function • Slower onset than ARF – once you are in chronic stage, you can rarely come out of it • 5 stages determined by GFR

Causes:

• Diabetes mellitus
• HTN
• Chronic glomerulonephritis
• PKD, poorly treated ARF
• Pyelonephritis
• Obstructions
• Infections
• Medications
• Toxic agents

Risk factors:

• Hyperlipidemia
• Smoking
• Recreational drugs
• NSAIDs
• Atherosclerosis
• Add stress to the kidneys

CKD Clinical Manifestations

CV

– HTN

– Heart failure – Pitting edema – Uremic Pericarditis/ Pericardial effusions – Dysrhythmias

In response to added amount of fluid in the body as well as elevated levels of electrolytes

Pulmonary – Crackles – Shortness of breath

Results from fluid overload

GI  Uremic fetor- “urine breath” – buildup of uremic waste products trying to escape  Metallic taste  N/V, constipation or diarrhea  Mouth ulceration  Results from waste products in the blood

Neurologic • Weakness and fatigue • Confusion • Seizures • Behavior changes • Results from elec and fluid imbalances

Musculoskeletal

• Muscle cramps – ab levels of electrolytes
• Bone fractures – loss of calcium and phosphate

Dermatologic

• Pruritis – buildup of uremic waste products that results in itching
• Dry, flaky skin
• Gray-bronze skin

Hematologic ➢ Anemia – loss of erythopoeitin ➢ Thrombocytopenia

Metabolic acidosis ➢ Decreased acid clearance ➢ Decreased bicarbonate ➢ Kidneys are not able to excrete waste products

PO4 and Ca in CKD

• Normally-

• Ca and PO4 is absorbed from GI tract
• Ca is bound to Vit D in kidneys (Calcitrol) preventing excretion and hypocalcemia (the

binding is what prevents it from being excreted)

• Renal Failure-

• Kidneys don’t work → no Ca binding → excessive Ca loss in urine → hypocalcemia

• Low serum Ca levels simulate PTH release from parathyroid

• PTH → bone resorption (bone will break itself down) → release of PO4 and Ca into

circulation (to correct hypocalcemia)

• PO4 levels rise but Ca is still being lost in urine r/t kidney dysfunction →

• Hyperphospatemia, hypocalcemia, eventual osteoporosis and possible pathologic fractures

(calcium is still not binding and it is still hypocalcemia) and it is a never ending cycle

Test Normal Value Value in Renal Failure Creatinine 0.5-1.2 mg/dL Increased BUN 10-20 mg/dL Increased Serum Na 135-145 mEq/L Normal/decreased Serum K 3.5-5 mEq/L Increased Serum Phosphate 2.4-4.5 mg/dL Increased Serum Ca 8.2-10.2 mg/dL Decreased

Arterial pH 7.35-7.45 Decreased Hemoglobin Male- 14-18 g/dL Female- 12-16 g/dL Decreased Hematocrit Male- 43%-49?male- 38%-44?creased Urine Protein 6-8 g/dL Increased Creatinine Clearance 88-137 mL/min Decreased GFR 125 mL/min Decreased

Medical Management of CKD

• Identify and treat cause if possible

*** Primary goal of treatment is to remove waste products- renal replacement therapies (to make up where the kidneys are failing)

• Secondary goals- support remaining kidney function, treat patient’s s/sx, and prevent complications

• Management of:

– Hyperkalemia

– HTN

– Renal osteodystrophy – Secondary Hyperparathyroidism – Hypocalcemia – Anemia

Hyperkalemia:

– Elevated levels of K → life-threatening dysrhythmias

– K decreases the threshold necessary to generate an action potential → peaked T waves → long PR intervals → wide QRS complexes

– Emergency • Stabilize myocardial cell membrane- IV Ca gluconate