Acute Kidney Injury

the movement of fluid and solutes from teh vascular system to the tubular system of the nephron

the volume of plasma that can be cleared of a substance within a set time frame

• Maintain fluid and electrolyte balance
• Maintains acid-base balance
• Excretes nitrogeneous end products of protein
• Activates vitamin D
• Secretes erythropoietin
• ESRD pts: chronically anemic bc kidneys and bone marrow can't make more RBCs

• 25, OH (supplements): inactive, used by kidneys; unusable by body
• 125, OH: active and usable for cells
• Conversion takes place in kidneys

• azotemia: retention of BUN and Cr
• imbalances in fluids and electrolytes
• acid-base disorders
• decreased urine output

• a decrease in effective renal perfusion resulting in a decreased GFR and kidney function
• MAP >70-75 mmHg should be maintained to perfuse kidneys
• Urine output of at least 25-30ml/hr

• Excessive fluid loss: hemorrhage, burns, vomiting, diarrhea, acities
• Decreased renal perfusion: HF, decreased CO, MI, shock, tumor, vascular obstruction; kidneys one of last organs to get perfusion in emergencies
• Glomerular arteriole vasodilation or constriction: ACE-inhibitors, NSAIDS, cyclosporine

• Most common: ATN: from ischemia, sepsis, drugs (big)
• Renal tubular ischemia
• Nephrotoxicity: from contrast dye (big), antibiotics, NSAIDS, chemicals
• Rhabdomyolysis: muscle breakdown w/ myoglobin release (urine is dark red, toxic to kidneys)
• Intratubular obstruction

• Permanent injury
• Only thing can do is fix cause and keep from getting worse

• Calculi
• Clots
• Prostatic hypertrophy
• Strictures
• Edema
• Tumors
• Obstructed catheter (kinks/clots)
• Diabetic neuropathy
• Pregnancy
• Drugs (narcotics, PCA)
• Spinal cord injury

• Neuro: decreased alertness (buildup of nitrogeneous wastes, ph issues), drowsiness, seizures (f/e imbalances), coma
• Cardiac: HTN, dysrythmias, edema
• Pulmonary: decreased cough reflex (decreased LOC, RR), crackles, infiltrates
• GI: weight loss (will stop eating bc vomiting), anorexia, N/V, constipation (phosphorus imbalances), diarrhea

• Hematopoietic: anemia (decreased erythropoietin production), fatigue, weakness, platelet function impaired (presence of uremic toxins)
• Skin: pale, dry, dull, yellow skin, bruising (impaired platelets), pruritis, thin hair, brittle nails
• Skeletal: disorders r/t decreased calcium absorption, fractures

Azotemia Oliguria/AnuriaCould be compensatory mechanisms to decreased intravascular blood flow

Increased

Increased

Increased

Decreased

Increased

Increased

Decreased

Increased

Decreased

• Diuretic therapy
• Dialysis
• Fluid restriction (may allow 1L/day)
• Monitor for: imbalanced I&O, edema, pulmonary crackles, HTN, weight gain

• Protien, Na, K+, and fluid restircted diet
• High carb, fat, and amino acid diet
• Dialysis to decrease BUN & Cr
• Monitor for: weight gain, neuro changes, GI dysfunction, decreased serum protein levels

• Administer Kayexylate via oral, gastric, or rectal routes (if doesn't have BM in 4-6hrs, K+ will not be removed)
• Administer IV sodium bicarb, insulin followed by D5 (prevent hypoglycemia), then hypertonic glucose to move K+ into cells
• Hemodialysis
• ECG changes: prolonged QRS, tall, peaked T waves

• Sodium bicarb (severe cases)
• IV or dialysate additive

• Limit oral and IV Na
• Diuretics for hypernatremia (use cautiously)

• Strict medical asepsis w/ all invasive lines
• Antibiotics
• Monitor for: elecated WBC, fever, positive blood cultures

• Filter toxins and excess water from blood
• Toxins removed by diffusion
• Fluid removed by ultrafiltration by pressure gradient across semipermeable membrane

• Pts w/ renal failure who were on peritoneal dialysis and got an infection
• When PD cannot adequately remove wastes
• More efficient in clearing blood, but more destabilizing

• BUN >100
• Cr >10
• Hyperkalemia, drug toxicity, met. acidosis, fluid overload, pulmonary edema
• S/S of uremia: pericarditis, GI bleeding, encephalopathy
• Contraindications to other forms of dialysis
• Transfusion rx

• Hemodynamic instability (biggest)
• Coagulopathies
• Lack of access to circulation
• Age extremes (children and elderly)

Dual lumen subclavian or femoral vein catheter (Udall, Quinton, or Tesio)

Internal arteriovenous (AV) fistula

• Need for fluid volume removal in a hemodynacially unstable pt
• Hypervolemia unresponsive to diuretics
• MODS
• Coagulapathies
• Ease of fluid management
• PD/HD contraindications

• Hct >45%
• Lack of arterial/venous access

• Venous and arterial access obtained, fluid and moderate solute removal
• Driven by pt's BP

• Venous and arterial access obtained
• Allows for fluid removal plus maximum solute removal
• Driven by pt's BP
• Dialysate bag used

• Double lumen catheter placed in vein
• Blood pumped through filter
• Removes solutes and fluid

• Double lumen catheter placed in vien
• Blood pumped though a filter
• Removes solutes and fluid
• Dialysate bag used

• Used when surgeon blieves standard AV fistula will not work
• An artery and vein are joined w/ an artificial substance (bovine graft) or w/ the saphenous or umbilical veins

• Monitor of increased risk for bleeding 6hr post HD (on heparin and anticoags)
• BP q 5-15min
• HR q 5-15min
• PCWP q 1-2hrs
• Respiratory pattern q 1hr
• Neuro status q 1hr
• Continous cardiac monitoring

• Hypotension: lower HOB, raise feet, slow rate of ultrafiltration, IV volume expanders, vasopressors, blood products
• Dysrythmias
• Bleeding

• Dialyste instilled at body temp
• Weight pt before 1st and after last exhange
• Document I&O
• Restrict fluid intake
• Monitor, assess, and report changes in VS, LOC
• Watch and prevent peritonitis
• Drain if SOB occurs
• Small feedings to prevent nausea
• Skin care
• Tenchoff catheter care: sterile dressing
• Prevent infection

• Rebound tenderness
• Severe abdominal pain
• Guarding
• Distention
• Cloudy drainage
• Fever
• Leukocytosis
• Change in LOC