- Three classification systems exist for staging severity of acute kidney injury (AKI): (a) Risk, Injury, Failure, Loss of Kidney Function, and End-Stage Kidney Disease (RIFLE), (b) Acute Kidney Injury Network (AKIN), and (c) Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guidelines. All three classification systems are based on separate criteria for serum creatinine (Scr) and urine output.
- AKI is a common complication in hospitalized patients and is associated with high morbidity and mortality, especially in critically ill.
- AKI is categorized based on three distinct types of injury: (a) prerenal—decreased renal blood flow, (b) intrinsic—structural damage within the kidney, and (c) postrenal—an obstruction is present within the urine collection system.
- Conventional formulas used to determine estimated glomerular filtration rate (eGFR) and creatinine clearance should not be used to estimate renal function in patients with AKI. This may be especially true for medication dosing adjustments.
- Prevention is of utmost importance since there are very few therapeutic options available for the treatment of established AKI.
- Supportive management remains the primary approach to prevent or reduce the complications associated with AKI. Supportive therapies include renal replacement therapy (RRT), nutritional support, avoidance of nephrotoxins, and blood pressure and fluid management.
- For those patients with prolonged or severe AKI, RRT is the cornerstone of support along with an aggressive approach to fluid, electrolyte, and waste management.
- Drug dosing for AKI patients receiving continuous renal replacement therapy (CRRT) or sustained low-efficiency dialysis (SLED) is poorly characterized. Dosing regimens should be individualized and therapeutic drug monitoring utilized whenever possible.
- Diuretic resistance is a common phenomenon in the patient with AKI and can be addressed with sodium restriction, combination diuretic therapy, or a continuous infusion of a loop diuretic.
On completion of the chapter, the reader will be able to:
Identify patients at high risk of developing acute kidney injury (AKI).
Compare and contrast the three main classification systems for AKI: (a) Risk, Injury, Failure, Loss of Kidney Function, and End-Stage Kidney Disease (RIFLE); (b) Acute Kidney Injury Network (AKIN); and (c) Kidney Disease: Improving Global Outcomes (KDIGO).
Describe the pathophysiology and etiology of prerenal, intrinsic, and postrenal AKI.
Determine the type of AKI a patient is experiencing from an assessment of the patient’s history, physical examination findings, and laboratory results.
Discuss the pros and cons of conventional versus novel biomarkers of kidney function as they pertain to a patient with AKI.
Propose (non)pharmacologic strategies to decrease the risk of contrast-induced nephropathy.
Distinguish effective versus ineffective (non)pharmacologic strategies for prevention of AKI based on evidence-based literature and KDIGO guidelines.
Assess the impact of the various supportive therapies during the course of AKI.
Provide patient-specific monitoring recommendations for a patient with established AKI.
Compare and contrast intermittent versus continuous renal replacement therapies.
Discuss pros and cons of renal replacement therapy in the prevention and management of AKI.
Devise a strategy to manage diuretic resistance in a volume-overloaded patient with AKI.
Interpret the most common electrolyte disturbances in patients ...