Preferred Initial Resuscitation Fluid in Non-TBI Critically Ill ICU Patients
Balanced crystalloids (such as Plasma-Lyte or lactated Ringer's) should be used as the first-line resuscitation fluid for critically ill ICU patients without traumatic brain injury, as they reduce mortality and major adverse kidney events compared to normal saline. 1, 2
Primary Recommendation
Balanced crystalloids are associated with lower 30-day mortality (OR 0.84,95% CI 0.74-0.95) and reduced major renal events in critically ill patients, particularly those with sepsis. 2
Meta-analyses including 35,884 critically ill patients demonstrate that balanced crystalloids reduce mortality in the general ICU population compared to normal saline. 2
In non-TBI patients specifically, balanced crystalloids achieve lower mortality than normal saline (RR: 0.94; 95% CI 0.90-0.99). 3
Why Balanced Crystalloids Are Superior
Balanced crystalloids have electrolyte compositions closer to plasma, which prevents hyperchloremic metabolic acidosis that occurs with large-volume normal saline administration. 1
Hyperchloremic acidosis from high-chloride fluids causes renal vasoconstriction and acute kidney injury, with increased 30-day mortality when hyperchloremia develops. 1, 2
Large volume 0.9% saline (>5000 mL) is associated with increased mortality and major adverse kidney events in observational studies. 2
Specific Balanced Crystalloid Options
Plasma-Lyte contains sodium 140 mmol/L, potassium 5 mmol/L, chloride 98 mmol/L, acetate 27 mmol/L, with osmolarity of 295 mOsm/L. 4
Lactated Ringer's contains sodium 130 mmol/L, potassium 4 mmol/L, chloride 108 mmol/L, calcium 0.9 mmol/L, lactate 27.6 mmol/L, with osmolarity of 277 mOsm/L. 4
Both are appropriate choices for non-TBI patients, though Plasma-Lyte has slightly higher osmolarity (295 vs 277 mOsm/L). 4
Clinical Scenarios Where Balanced Crystalloids Excel
Sepsis and septic shock: Balanced crystalloids show mortality benefit, particularly when initiated in the emergency department (OR 0.68,95% CI 0.52-0.89). 1, 2
Hemorrhagic shock: European guidelines favor balanced crystalloids as initial crystalloid solution, especially when large volumes (5-10 L in first 24 hours) are required. 2
Emergency surgery and trauma (non-TBI): Balanced crystalloids reduce complications compared to normal saline, with dose-response relationship between normal saline volume and adverse outcomes. 2
Renal patients: Balanced crystalloids reduce mortality and adverse renal events in patients at risk for acute kidney injury. 1
Fluids to Avoid in Non-TBI Patients
Synthetic colloids (hydroxyethyl starch, gelatins) increase risk of acute renal failure (RR 1.34,95% CI 1.0-1.8) without mortality benefit and should be avoided. 2, 4
Albumin shows no mortality benefit over crystalloids and costs significantly more, making routine use unjustified. 2
Large volume normal saline should be avoided due to association with hyperchloremic acidosis, increased mortality, and major adverse kidney events. 1, 2
Initial Resuscitation Protocol
For sepsis: Administer 30 mL/kg balanced crystalloid bolus initially, targeting mean arterial pressure ≥65 mmHg, urine output ≥0.5 mL/kg/h, and improved mental status and peripheral perfusion. 2
Monitor hourly: Urine output, mean arterial pressure, heart rate, mental status, and peripheral perfusion during resuscitation. 2
Stop fluid administration when there is no improvement in tissue perfusion with volume loading, or when pulmonary crepitations develop indicating overload. 2
Critical Pitfalls to Avoid
Do not assume potassium in balanced crystalloids is dangerous for critically ill patients—the potassium concentration (4-5 mmol/L) is equal to or lower than plasma concentration and cannot create potassium excess physiologically. 1, 4
Do not use outdated protocols from before 2018 that recommend large volume normal saline, as current evidence demonstrates harm. 1
Do not delay balanced crystalloid initiation until ICU admission—benefits are most pronounced when started in the emergency department. 1, 2