What are the best resources for managing Acute Kidney Injury (AKI) in sepsis?

From the Guidelines

For sepsis-associated acute kidney injury (AKI), the best resources include the Surviving Sepsis Campaign guidelines, KDIGO (Kidney Disease: Improving Global Outcomes) guidelines, and institutional protocols focused on early recognition and management. These resources emphasize prompt sepsis treatment with appropriate antibiotics within one hour of recognition, along with adequate fluid resuscitation using balanced crystalloids like lactated Ringer's solution (typically 30 ml/kg initially) 1.

Key Recommendations

• Hemodynamic monitoring is crucial, with mean arterial pressure targets of >65 mmHg using norepinephrine as the first-line vasopressor (starting at 0.05-0.1 mcg/kg/min) 1.
• Avoid nephrotoxic agents when possible, including NSAIDs, aminoglycosides, and contrast media 1.
• Regular monitoring of kidney function through serum creatinine, urine output (targeting >0.5 ml/kg/hr), and electrolyte balance is essential.
• For patients with established AKI, consider renal replacement therapy when indicated for severe acidosis, hyperkalemia, or fluid overload, using either continuous RRT (CRRT) or intermittent RRT as both are suggested to be used in patients with sepsis and acute kidney injury (weak recommendation, moderate quality of evidence) 1.

Rationale

These approaches are recommended because sepsis-induced AKI results from a complex interplay of inflammation, microcirculatory dysfunction, and direct cellular injury, requiring a multifaceted management strategy focused on treating the underlying sepsis while supporting kidney function. The use of protocol-based management of hemodynamic and oxygenation parameters to prevent the development or worsening of AKI in high-risk patients in the perioperative setting or in patients with septic shock is also suggested (2C) 1.

Additional Considerations

• Insulin therapy targeting plasma glucose 110-149 mg/dL (6.1-8.3 mmol/L) is suggested in critically ill patients 1.
• Achieving a total energy intake of 20-30 kcal/kg/d in patients with any stage of AKI is recommended 1.
• Administering 0.8-1.0 g/kg/d of protein in noncatabolic AKI patients without need for dialysis, 1.0-1.5 g/kg/d in patients with AKI on RRT, and up to a maximum of 1.7 g/kg/d in patients on continuous renal replacement therapy (CRRT) and in hypercatabolic patients is suggested 1.

From the Research

Management of Acute Kidney Injury (AKI) in Sepsis

• The management of sepsis-induced AKI involves early and ample fluid resuscitation, preferably with crystalloid solutions 2.
• Balanced crystalloids have no proven superior benefit over other crystalloid solutions 2.
• Renal function can be evaluated by measuring lactate clearance rate, renal Doppler, or central venous oxygenation monitoring 2.
• Assuring sufficiently high central venous oxygenation is crucial in preventing SAKI, especially in the post-operative setting 2.
• Noradrenaline is the vasopressor of choice for preventing SAKI 2.
• Intra-abdominal hypertension should not be neglected in sepsis as it can trigger AKI in post-operative and trauma patients 2.

Treatment Strategies

• Early renal replacement therapy (RRT) is recommended in fluid-overloaded patients who are refractory to diuretics, but compelling evidence about its usefulness is still lacking 2.
• Continuous RRT (CRRT) is advocated as the preferred modality in hemodynamically unstable SAKI, although not sustained by convincing data 2.
• Diuretics should be avoided in the absence of hypervolemia 2.
• Antimicrobial dosing during CRRT needs to be thoroughly reconsidered to assure adequate infection control 2.

Prevention and Epidemiology

• Sepsis-associated acute kidney injury (S-AKI) is a frequent complication of critically ill patients and is associated with unacceptable morbidity and mortality 3.
• Prevention of S-AKI is difficult because most patients have already developed acute kidney injury by the time they seek medical attention 3.
• Early recognition is crucial to provide supportive treatment and limit further insults 3.
• Novel biomarkers of kidney stress and damage have been recently validated for risk prediction and early diagnosis of acute kidney injury in the setting of sepsis 3.

Pathophysiology and Landmark Trials

• Microvascular dysfunction, inflammation, and metabolic reprogramming are fundamental mechanisms that may play a role in the development of S-AKI 3.
• The pathophysiology of S-AKI is complex and not fully understood, requiring more mechanistic studies to translate findings into potential treatment strategies 3.
• Landmark trials in fluid resuscitation in sepsis have been reviewed, highlighting the importance of fluid management in preventing and treating AKI 4.