What is the management of Acute Kidney Injury (AKI) in cardiogenic shock?

From the Guidelines

The management of acute kidney injury (AKI) in cardiogenic shock should prioritize hemodynamic stabilization with vasopressors like norepinephrine and inotropes such as dobutamine to improve cardiac output and renal perfusion, as recommended by the 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 1. The initial approach should focus on improving cardiac output while protecting renal function.

• Hemodynamic stabilization with vasopressors like norepinephrine (starting at 0.05-0.1 mcg/kg/min) and inotropes such as dobutamine (2.5-10 mcg/kg/min) is crucial to improve cardiac output and renal perfusion.
• Mechanical circulatory support with devices like intra-aortic balloon pumps or Impella may be necessary in severe cases, although the routine use of an IABP is not recommended based on the IABP-SHOCK II trial 1.
• Fluid management is critical, aiming to avoid volume overload while maintaining adequate perfusion, using careful assessment of volume status with physical examination, central venous pressure monitoring, and echocardiography.
• Nephrotoxic medications should be discontinued, including NSAIDs, aminoglycosides, and contrast agents when possible, as suggested by the KDIGO clinical practice guideline for acute kidney injury 1.
• Diuretics like furosemide (20-40mg IV initially, titrated as needed) may help manage volume overload but should be used cautiously to avoid worsening prerenal azotemia.
• Continuous renal replacement therapy (CRRT) should be initiated early if there is refractory hyperkalemia (K+ >6.5 mEq/L), severe acidosis (pH <7.2), uremic symptoms, or volume overload unresponsive to diuretics.
• Regular monitoring of renal function, electrolytes, and acid-base status is essential, with adjustments to medication dosing based on estimated glomerular filtration rate, as recommended by the KDIGO guideline 1. This approach addresses the pathophysiologic cycle where cardiac dysfunction reduces renal perfusion, leading to AKI, which can further worsen cardiac function through fluid overload and electrolyte disturbances.

From the FDA Drug Label

Dopamine Hydrochloride in 5% Dextrose Injection, USP is indicated for the correction of hemodynamic imbalances present in shock due to myocardial infarction, trauma, endotoxic septicemia, open heart surgery, renal failure and chronic cardiac decompensation as in refractory congestive failure Although urine flow is apparently one of the better diagnostic signs for monitoring vital organ perfusion, the physician also should observe the patient for signs of reversal of mental confusion or coma. Reported studies indicate that when dopamine is administered before urine flow has decreased to approximately 0. 3 mL/minute prognosis is more favorable. However, it has been observed that in some oliguric or anuric patients, administration of the drug has produced an increase in urine flow which may reach normal levels.

The management of Acute Kidney Injury (AKI) in cardiogenic shock with dopamine involves administering the drug to increase urine flow and improve cardiac output. Dopamine may help increase urine flow in patients with oliguric or anuric AKI, and its administration before urine flow decreases to approximately 0.3 mL/minute may lead to a more favorable prognosis 2. Key considerations include:

• Monitoring urine flow as a diagnostic sign for vital organ perfusion
• Observing patients for signs of reversal of mental confusion or coma
• Administering dopamine before urine flow decreases to approximately 0.3 mL/minute for a more favorable prognosis
• Potential for additive or potentiating effect when concomitantly administered with diuretic agents

From the Research

Management of AKI in Cardiogenic Shock

• Acute kidney injury (AKI) is a common complication in patients with cardiogenic shock (CS) and is associated with increased morbidity and mortality 3.
• The management of AKI in CS involves identifying risk factors and possible therapeutic interventions, including vasopressor choices, mechanical circulatory support, and renal replacement therapy 3.
• Vasopressor use in CS is limited by their side-effects and the lack of solid evidence regarding their effectiveness in improving outcomes, but norepinephrine may be preferred over epinephrine in patients with CS, particularly after myocardial infarction 4, 5.
• The use of epinephrine compared to norepinephrine in patients with CS secondary to acute myocardial infarction was associated with a higher incidence of refractory shock 5.
• Optimal CS management depends on early recognition, rapid reversal of the underlying cause, and prompt initiation of hemodynamic support, including the use of mechanical circulatory support and renal replacement therapy 6.
• Guidelines for evidence-based management of patients with cardiogenic shock after acute myocardial infarction focus on early revascularisation of the occluded coronary artery, support of cardiac failure, and improvement of impaired organ perfusion 7.
• The treatment of shock complications, especially acute respiratory failure and other forms of multiple organ dysfunction syndrome (MODS), is also of great importance in the management of CS 7.