Acute Kidney Injury admission

Most of the times, Acute Renal Failure is noticed in patients who are admitted to ER with some other Acute illness like any infection, vomiting, diarrhea etc.

ER:

IV Fluids-ER usually gives one or two liters of iv fluid boluses.

UA, Urine Creatinine

Foley Catheter-if there is urinary retention due to BPH

Hospitalist:

IVF-Most patients with mild AKI improve with iv fluids.

US Kidney and Urinary Bladder–>Urology Consult if there is bladder obstruction due to BPH leading to hydronephrosis.

In general, Do not do any CT or MRI with IV contrast if patient is in AKI.

Discontinue ACEI/ARBs, HCTZ, Lasix, NSAIDs, BP meds if there is hypotension.

Bicarbonate drip if Metabolic Acidosis

Nephrology consult if severe AKI. Mild AKI usually improves by next day with iv fluids.

If AKI is not improving despite iv fluids, you may be dealing with ATN in which case you need to involve nephrologist.

Some theoretical concepts but most are not that challenging.

Metabolic Acidosis:

M – Methanol

U – Uremia

D – DKA

P – Paraldehyde

I – Isoniazid

L – Lactic Acid

E – Ethanol, Ethylene glycol

S – Salicylates

Metabolic Acidosis with a Normal Anion Gap:

Longstanding diarrhea (bicarbonate loss)

Uretero-sigmoidostomy

Pancreatic fistula

Renal Tubular Acidosis

Intoxication, e.g., ammonium chloride, acetazolamide, bile acid sequestrants

Renal failure

Consider RTA if patients have metabolic acidosis with a normal anion gap or unexplained hyperkalemia.

 Feature Type 1 Type 2 Type 4
Incidence Rare Very rare Common
Mechanism Impaired H+ excretion in the distal tubule Impaired HCO3 resorption in the proximal tubule Decrease in aldosterone secretion or activity
Plasma HCO3(mEq/L) Usually < 15, often < 10 Usually 12–20 Usually > 17
Plasma K Usually low but tends to normalize with alkalinization Usually low and decreased further by alkalinization High
Urine pH > 5.5 Treat with HCO3 > 7 if plasma HCO3 is normal < 5.5 if plasma HCO3 is depleted (eg, <15 mEq/L) Treat with NaHCO3/K Citrate/Thiazide < 5.5 Treat with Diuretic, Low K diet
*Type 3 is very rare.

Metabolic Acidosis with an Elevated Anion Gap:

  • Lactic acidosis
  • Ketoacidosis
  • Chronic renal failure (accumulation of sulfates, phosphates, uric acid)
  • Intoxication, e.g., salicylates, ethanol, methanol, formaldehyde, ethylene glycol, paraldehyde, INH, toluene, sulfates, metformin.
  • Rhabdomyolysis

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