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% NaCl, patients are at increased risk of acid base imbalance, renal vasoconstriction and glomerular filtration 

• Vasopressor:

Norepinephrine improves renal blood flow, GFR and urine output by systemic vasoconstriction. Norepinephrine preferentially increases afferent arteriolar tone but it also increases renin release and angiotensin II formation which preferentially increase efferent arteriolar tone. 

• Avoidance of diuretics: 

• It is associated with intravascular volume reduction and prerenal insult.

• The use of mannitol is also not recommended. 

• Avoiding of anemia and transfusion:

• Stored allogenic blood transfusion is related with promoting oxidative stress and proinflammatory state 

• Preoperative anemia is associated with perioperative AKI.

• Glycemic control and nutritional support:

• Protein calorie malnutrition is a significant risk factor for AKI.

• It is recommended to maintain blood glucose between 110 - 149 mg/dl in critically ill patients.

• Pharmacological intervention:

Dexmedetomidine (α2 agonist) is associated with increased renal flow and decreased oxidative stress. It is associated with decreased norepinephrine release.

• Renal replacement therapy 
• Remote ischemic preconditioning: 

In recent study, it is associated with decrease acute kidney injury in high risk patients undergoing cardiac surgery. 

Further reading:
Perioperative Acute Kidney Injury

Perioperative acute kidney injury