What are the principles of fluid management in a critically ill patient with potential complications such as hypotension, hypercalcemia, or impaired renal function?

From the Guidelines

Fluid management in critically ill patients should prioritize the use of buffered crystalloid solutions, such as Lactated Ringer's or Plasma-Lyte, as the initial fluid of choice, unless there is a specific contraindication, such as hypochloraemia, in which case 0.9% saline may be considered. This approach is supported by the most recent and highest quality evidence, including a 2024 study published in the British Journal of Anaesthesia 1, which provides strong recommendations for the use of buffered crystalloid solutions and against the use of synthetic colloids and routine use of albumin.

When managing fluid in critically ill patients, it is essential to balance the need for adequate resuscitation with the risk of fluid overload. Initial resuscitation should begin with crystalloids, typically 30 ml/kg of balanced solutions, administered within the first 3 hours for patients with sepsis or shock. After this initial bolus, fluid administration should be guided by dynamic parameters rather than static measurements, such as passive leg raise tests, stroke volume variation, or ultrasound assessment of inferior vena cava collapsibility, to determine fluid responsiveness.

Key considerations in fluid management include:

• Using balanced crystalloids over normal saline to reduce the risk of hyperchloremic metabolic acidosis and acute kidney injury
• Considering albumin 5% or 25% as a second-line option, particularly in septic patients requiring substantial fluid volumes
• Frequently reassessing fluid administration using an ABCDEF approach: Assess for fluid need, Bolus (250-500 ml over 15-30 minutes), Check response with objective parameters, Determine ongoing losses, Evaluate overall fluid status, and Fix any underlying causes
• Initiating vasopressors, such as norepinephrine starting at 0.05-0.1 mcg/kg/min, early if fluid resuscitation doesn't restore adequate perfusion
• Shifting focus to achieving neutral or negative fluid balance once the patient is stabilized, potentially using diuretics like furosemide (20-40 mg IV every 12 hours) or continuous renal replacement therapy in appropriate cases, as supported by guidelines from the Surviving Sepsis Campaign 1 and the AASLD practice guidance on acute-on-chronic liver failure and the management of critically ill patients with cirrhosis 1.

Overall, the goal of fluid management in critically ill patients is to provide adequate tissue perfusion while minimizing the risk of complications from fluid overload, and this should be guided by the most recent and highest quality evidence available, including studies published in reputable journals such as the British Journal of Anaesthesia 1 and Hepatology 1.

From the FDA Drug Label

Blood volume depletion should always be corrected as fully as possible before any vasopressor is administered. When, as an emergency measure, intraaortic pressures must be maintained to prevent cerebral or coronary artery ischemia, LEVOPHED can be administered before and concurrently with blood volume replacement The degree of dilution depends on clinical fluid volume requirements. If large volumes of fluid (dextrose) are needed at a flow rate that would involve an excessive dose of the pressor agent per unit of time, a solution more dilute than 4 mcg per mL should be used

• Fluid management in critically ill patients involves correcting blood volume depletion before administering vasopressors like norepinephrine.
• Blood volume replacement should be done concurrently with norepinephrine administration if necessary, to maintain intraaortic pressures and prevent ischemia.
• The degree of dilution of norepinephrine depends on the patient's clinical fluid volume requirements 2.

From the Research

Fluid Management in Critically Ill Patients

• The European Society of Intensive Care Medicine clinical practice guideline on fluid therapy in adult critically ill patients provides conditional recommendations for using crystalloids rather than albumin in critically ill patients in general, in patients with sepsis, in patients with acute respiratory failure, and in patients in the perioperative period and patients at risk for bleeding 3.
• The guideline also provides conditional recommendations for using balanced crystalloids rather than isotonic saline in critically ill patients in general, in patients with sepsis, and in patients with kidney injury 3.
• The "salvage, optimization, stabilization, de-escalation" (SOSD) mnemonic should be used as a general guide to fluid resuscitation, and fluid administration should be adapted according to the course of the disease 4.
• Crystalloids are the preferred solution for the resuscitation of emergency department patients with severe sepsis and septic shock, and balanced crystalloids may improve patient-centered outcomes and should be considered as an alternative to normal saline, if available 5.
• The European Society of Intensive Care Medicine (ESICM) 2025 clinical practice guideline on fluid therapy in adult critically ill patients suggests administering up to 30 ml/kg of intravenous crystalloids in the initial phase, with adjustments based on clinical context and frequent reassessments 6.

Choice of Resuscitation Fluids

• Crystalloids are cheaper than colloid solutions, but colloid solutions remain in the intravascular space for a longer period, making edema less likely 4.
• Human albumin is a natural colloid and may have beneficial effects in patients with sepsis in addition to its volume effects 4.
• Starch use was associated with increased mortality in two large clinical trials, and starches probably have significant renal adverse effects and may be related to more need for renal replacement therapy in severe sepsis 7.
• Albumin is the only colloid that has been shown safe in patients with sepsis and that may be associated with improved outcomes on specific subpopulations 7.

Volume of Resuscitation Fluids

• The ESICM guideline suggests using an individualized approach in the optimization phase, and no recommendation could be made for or against restrictive or liberal fluid strategies in the optimization phase 6.
• For hemorrhagic shock, a restrictive fluid strategy is suggested after blunt trauma and penetrating trauma, with fluid administration for non-traumatic hemorrhagic shock guided by hemodynamic and biochemical parameters 6.
• Fluids should be administered cautiously for cardiac tamponade until definitive treatment and guided by surrogate markers of right heart congestion in acute pulmonary embolism 6.