What are evidence-based practices for preventing Acute Kidney Injury (AKI) in trauma patients?

From the Guidelines

To prevent acute renal injury in trauma patients, early and aggressive fluid resuscitation with balanced crystalloid solutions is crucial, targeting a mean arterial pressure of at least 65 mmHg and maintaining a urine output of >0.5 mL/kg/hr, as recommended by the most recent guidelines 1.

Key Considerations

• Early fluid resuscitation should be initiated as soon as possible, with a focus on balanced crystalloid solutions like lactated Ringer's to prevent hyperchloremic acidosis 1.
• The volume of fluid administration should be individualized based on the patient's condition, with a general recommendation of 3-6 L per day for moderate rhabdomyolysis and potentially higher volumes for severe cases 1.
• Regular monitoring of kidney function, including serum creatinine, urine output, and electrolyte levels, is essential to promptly identify any signs of acute kidney injury 1.
• Minimizing exposure to nephrotoxic medications, such as NSAIDs, aminoglycosides, and contrast media, is also critical in preventing acute renal injury 1.

Specific Recommendations for Rhabdomyolysis

• Aggressive fluid resuscitation with a target urine output of 1-2 mL/kg/hr and urine alkalinization with sodium bicarbonate (maintaining urine pH >6.5) can help prevent myoglobin-induced kidney injury 1.
• Early renal replacement therapy should be considered in patients with severe metabolic derangements or fluid overload 1.

Overall Strategy

• The primary goal is to maintain adequate renal perfusion and avoid nephrotoxic agents, with a focus on early and aggressive fluid resuscitation and regular monitoring of kidney function 1.
• By following these evidence-based practices, clinicians can help reduce the risk of acute renal injury in trauma patients and improve overall outcomes.

From the Research

Prevention of Acute Renal Injury in Trauma Patients

• The use of balanced crystalloids versus normal saline in fluid resuscitation has been studied in critically ill patients, including trauma patients, with mixed results 2, 3.
• A systematic review and meta-analysis found no significant difference in mortality, acute kidney injury (AKI), or new renal replacement therapy (RRT) between balanced crystalloid solutions and normal saline in critically ill patients 2.
• However, another study found that the use of balanced crystalloids may reduce the risk of death in patients with non-traumatic brain injury, but increase the risk of death in those with traumatic brain injury 2.
• The use of colloids versus crystalloids for fluid resuscitation in hypovolemic shock has also been studied, with one trial finding no significant difference in 28-day mortality, but a lower 90-day mortality in the colloid group 4.
• Risk factors for AKI in trauma patients include age, injury severity score, admission systolic blood pressure, lactate and serum creatinine, units of packed red blood cells transfused, and administration of nephrotoxic therapy 5.
• AKI is a frequent complication following trauma and is associated with prolonged hospital length of stay and increased mortality 5.
• Resuscitation with balanced solutes may have beneficial effects on renal outcome compared with normal saline, particularly in the context of rhabdomyolysis 6.
• Early identification of patients at risk of AKI and establishment of a resuscitation strategy that aims at preventing AKI is crucial in trauma patients 6.

Fluid Resuscitation Strategies

• Fluid resuscitation should be applied in a goal-directed manner and targeted to physiologic needs of individual patients 3.
• The use of fluids in volume-responsive patients whose end-organ perfusion parameters have not been met is supported by evidence 3.
• Balanced crystalloid solutions have shown no harmful effects and may have benefits over normal saline in preventing AKI 3, 6.

Future Research Directions

• Large-scale rigorous randomized trials with better designs are needed to confirm the benefits of balanced crystalloids over normal saline in preventing AKI in trauma patients 2, 6.
• Further research is needed to improve our ability to rapidly identify those at risk of AKI and develop resuscitation strategies that preserve renal function in trauma patients 5.