Showing posts from March, 2022

KDIGO classification of AKI (acute kidney injury)

  KDIGO (Kidney Disease: Improvement Global Initiative) definition of AKI is characterised by any of the following criteria: Increase S. Creatinine ≥ 0.3 mg/dl within 48 hrs, or  Increase S. Creatinine ≥ 1.5 times the baseline within last 7 days, or Urine volume < 0.5 ml/kg/hr for 6 hrs Severity of the disease is staged according to the following criteria: Stage 1: S. creatinine 1.5 - 1.9 times the baseline or Increase > 0.3 mg/dl  Urine output < 0.5 ml/kg/hr for 6 - 12 hrs  Stage 2: S. creatinine 2.0 - 2.9 times the baseline  Urine output < 0.5 ml/kg/hr for > 12 hrs  Stage 3: S. creatinine 3.0 times the baseline or Increase > 4.0 mg/dl  eGFR < 35 ml/min  Urine output < 0.3 ml/kg/hr for > 24 hrs Initiation of renal replacement therapy  KDIGO

Prevention and management of acute kidney injury (AKI) in perioperative period

Identification of High risk patient for developing perioperative AKI General consideration: Avoid to use aminoglycosides  Hemodynamic goal: Mean arterial pressure (MAP) < 60 mmHg for > 20 minutes and < 55 mmHg for > 10 minutes is associated with increased risk of acute kidney injury. In ICU settings, MAP > 60 - 65 mmHg and in chronically hypertensive patients > 75 mmHg is advised.  Fluid resuscitation approach:    A liberal approach for resuscitation is potentially safer than a restricted approach  Goal directed fluid therapy:   It involves titration of fluid boluses and inotropic agents to optimize cardiac output or markers of end organ perfusion.  It involves the use of -  Esophageal doppler  Pulse contour waveform analysis  Dilutional technique  Arterial lactate  IV fluid composition: Isotonic crystalloid is the standard first line resuscitation fluid therapy  A balanced crystalloid solution with electrolyte composition comparable to plasma is preferred With 0.9%

RIFLE classification of acute kidney injury (AKI)

  Stage I (Risk) Increase S. creatinine ≥ 1.5  fold from the baseline GFR decrease > 25% Urine output < 0.5 ml/kg/hr for > 6 hrs Stage II (Injury) Increase S. creatinine > 2 fold from the baseline  GFR decrease > 50% Urine output < 0.5 ml/kg/hr for > 12 hrs  Stage III (Failure) Increase S. creatinine > 3 fold from the baseline S. creatinine ≥ 4 mg/dl with acute rise of ≥ 0.5 mg/dl  GFR decrease > 75% Urine output < 0.3 ml/kg/hr for 24 hrs or anuria for 12 hrs  Stage IV (Loss) Complete loss of renal function for > 4 wks  Stage V (ESRD) Complete loss of renal function for > 3 months  

Causes of Acute kidney injury (AKI)

  Pre - renal conditions: Hypovolemia, Hemorrhage, Dehydration  Low cardiac state - acute or chronic heart failure Vasodilatory hypotension - sepsis  Chronic liver disease  Abdominal compartment syndrome  Medications - ACEI, ARB, NSAIDs, Radiocontrast agents    Intrinsic renal disease: Acute tubular injury  Autoimmune -  Glomerulonephritis  Interstitial nephritis  Vasculitis  Inflammatory -  Systemic inflammation  Sepsis  Rhabdomyolysis, Crash injury, Burn  Major surgery Cardiopulmonary bypass  Metabolic -  Hypercalcemia  Hyperuricemia Post renal conditions:  Prostatic hypertrophy  Nephrolithiasis  Bladder tumor  Pelvic mass

Risk factors of perioperative acute kidney injury (AKI)

 Preoperative factors: Age ASA III/ IV Preoperative kidney disease  Hepatic disease (Obstructive jaundice, chronic liver disease) Cardiac disease  Preeclampsia  Sepsis  Diabetes mellitus  Intraoperative factors: Hypotension, Hypovolemia, Hypoperfusion  Transfusion  Inotropes/ Vasopressor therapy  Emergency, Intraperitoneal, Transplant surgery  Postoperative factors: Nephrotoxins -  Radiocontrast agents  Certain antibiotics  ACEI NSAIDs Diuretics  Antiarrhythmics Sepsis