Developed by 91 Civil Affairs Presented/modified by 1BCT, 82D ABN DIV Acute Kidney Injury Developed by 91 Civil Affairs Presented/modified by 1BCT, 82D ABN DIV

Renal function Kidney has many roles: 1. Excretory function 2. Osmolality regulation 3. pH balance 4. BP regulation through salt and water balance 5. Hormone secretion (Erythropoietin, Vit D3)

Definition of Acute Kidney Injury Acute decline in renal function • Rapid ( < 48 hrs) • Seen as: A- Rise in serum creatinine, defined by either: 1- absolute increase in serum creatinine of >0.3mg/dl( >26μmol/l) 2- % increase in serum creatinine of > 50% B - Reduction in urine output, defined as < 0.5ml/kg/hr for more than 6 hrs or 30-50cc/hr

Mortality • 5-10% in uncomplicated AKI • 50-70% in AKI secondary to other organ failure( intensive care) • > 50% in dialysis

Diagnosing pre-renal AKI Signs of Hypovolemia: a. Low BP( and reduced pulse pressure) b. Postural BP drop ( a fall in systolic BP > 10mmHg) c. Sinus tachycardia and postural increase in heart rate ( increase in HR > 10 beat/min) e. Cool peripheries and vasoconstriction ( septic patients may be vasodilated) f. Poor urine output.

Resuscitate - Hypotensive and tachycardic 0.9% Normal saline be aware of fluid overload high BP, RR, basal lung crackles and low satO2) fluid challenge trial 200-300ml N saline IV in 10min, then re-assess, repeat if necessary

Replacement (after rescucitation is complete, then give the following) first liter over 2 hours, THEN REASSESS second liter over 4 hours, THEN REASSESS - third liter over 6 hours, THEN REASSESS

Maintenance Once euvolemic, and assume no other losses, match urine out put plus 30mls/hour (insensible loss may be higher if febrile)

Correcting Hypovolemia (from Up To Date) Overly aggressive volume repletion should be avoided as excessive volume expansion may lead to pulmonary congestion, especially in septic patients. We suggest judicious administration, beginning with 1 to 3 liters of fluid, with careful and REPEATED CLINICAL ASSESSMENT to assess the patient's response to this therapy. In some cases, additional fluid therapy may be necessary (eg, severe burns, acute pancreatitis).

Correcting Volume Depletion (From Up To Date) Overly aggressive volume repletion should be avoided as excessive volume expansion may lead to pulmonary congestion, especially in septic patients. We suggest judicious administration, beginning with 1 to 3 liters of fluid, with careful and REPEATED CLINICAL ASSESSMENT to assess the patient's response to this therapy. In some cases, additional fluid therapy may be necessary (eg, severe burns, acute pancreatitis).

RENAL (INTRINSIC) AKI (beyond the scope of this training, should not be down range)

POST-RENAL AKI Nature of Obstruction--Foley Outside - Tumors, prostate, retroperitoneal fibrosis, cervical Ca Within wall - Tumors, strictures Within lumen - Stones, tumors

Diagnosing post renal AKI 1. History: pain, anuria, hematuria, prostatism 2. Examination: palpable bladder, central abdominal mass, Post Void Residual 3. Observation 4. Laboratory investigations - Urine - Blood - Imaging – US, CT

Treatment of Post renal AKI Obtain drainage of Urine - Bladder catheter – per urethra, suprapubic - Retrograde drainage - Antegrade drainage

Post recovery diuresis Occurs post resolution of AKI - Post relief of obstruction - Post ATN Important to check fluid status - Clinical exam - BP and pulse - Daily weight - Input and output chart Treatment – IV fluids, replace electrolyte

Complications of AKI Pulmonary edema Acidosis Uremia Other electrolyte disturbance such as hyerphosphatemia and hypocalcemia

Who is a risk? 1- Elderly 2- Pre-existing renal disease 3- Surgery, trauma, sepsis or rhabdo 4- Diabetes 5- Volume depletion 6- LV dysfunction 7- Nephrotoxic drugs 8- Cirrhosis (reduce arterial volume)

Common nephrotoxins NSAID Antibiotics, Aminoglycosides, Vancomycin IV contrast