APPROACH TO RENAL EMERGENCIES

Question 1

DDx: Pre-renal AKI

Answer 1

Dehydration
GI Losses
Hemorrhage
Third Spacing (burn, sepsis)
Cardiogenic (CHD, myocarditis, cardiogenic shock)

Question 2

DDx: Intrinsic Renal AKI

Answer 2

Glomerular disease:
Henoch Schonlein Purpura
Glomerulonephritis
Nephrotic Syndrome
Pyelonephritis

Vascular disease:
Hemolytic Uremic Syndrome

Interstitial Disease:
Interstitial Nephritis

Tubular Disease:
Ischemia
Nephrotoxins (antibiotics, NSAIDs, contrast)

Question 3

DDx: Post Renal / Obstruction

Answer 3

Nephrolithiasis
Renal Vein Thrombosis
Pelvic Mass
Urethral Obstruction (posterior urethral valves, UPC obstruction)

Question 4

Investigations

Answer 4

CBC
Serum Creatinine
Serum Na, K, Ca, Mg, Pho
UA with microscopy

Question 5

Approach to the Critical AKI

Answer 5

PRE-RENAL

Mild - Moderate Hypovolemia:
Oral Rehydration Solution

Goal: replace deficits over 4-6 hrs and replace ongoing losses

Mild - 1 ml / kg / 5 min
Moderate - 2 ml / kg / 5 min

Pedialyte:

45 mEq/L Sodium
140 mEq/L Glucose

Severe Hypovolemia:
20 ml / kg IV bolus NS over 15-20 min
Repeat until perfusion improves and urine output is adequate

THEN
Maintenance 4 cc / hr for 1st 10 kg, 2 cc / hr for 10-20 kg, 1 cc / hr per kg for every kg > 20 kg

NO POTASSIUM SUPPLEMENT

Hemorrhage:
pRBC transfusion:
10 -15 mL/kg
2.5 mL/kg/hour (10 mL/kg over four hours)
Expected increase 2-3 g/dL

INTRINSIC

HTN:
Hydralazine
IV 0.1-0.4 mg / kg / DOSE q 4 h (max 20 mg / dose)
PO 0.25 mg / kg / DOSE (max 25 mg / dose) q6-8 hr

Nifedipine
0.125-0.25 mg / kg / dose (max 10 mg / dose) q4-6 hrs (max 2 mg / kg / day) PO

Fluid Restriction
Monitor Weight and liquid intake / output
Discontinue nephrotoxic meds

POST RENAL
Insert foley catheter