Operating Room IVF Requirements


Select a degree of tissue trauma from minimal to emergency trauma from the table below:

Trauma and IV fluid requirements
Trauma Level Example IV Fluid Requirement
Minimal eye cases, laparscopic cholecystectomy 1–2 mL/kg/hr
Low arthroscopies, ENT 3–4 mL/kg/hr
Moderate total joint replacements 5–6 mL/kg/hr
Severe bowel resection, total hip replacement 7–8 mL/kg/hr
Emergency gun shot, car accident–severe injuries 10–15 mL/kg/hr

Formula: Total IVF Maintenance Requirements

Insensible loss + 3rd space loss requirements

  • Insensible loss = 1-2 mL/kg/hr
  • 3rd space loss requirements depend on the type of trauma related to the surgical procedure that is being performed.
  1. Adjust IV fluids to maintain urine output of 1 mL/kg/hr. For comparison, oliguria is defined as a urine output of less than 0.5 mL/kg/hr.
  2. Infuse colloid solution to replace blood loss > 20% of patient's circulating volume.

Signs of Fluid Loss (hypovolemia)

Fluid loss expressed as % of body weight. Morgan & Mikhail (1996)
Sign 5% 10% 15%
Mucous Membranes Dry Very dry Parched
Sensorium Normal Lethargic Obtunded
Orthostatic Changes in Pulse or BP Mild Present Marked
Urinary Output Mildly decreased Decreased Markedly decreased
Heart Rate Normal or increased Increased Markedly increased
Blood Pressure Normal Mildly decreased Decreased


A 50 kg patient is scheduled for a laparoscopic cholecystectomy. What are the maintenance fluid requirements for this patient during surgery?

  • Tissue trauma is minimal
  • Insensible loss = 1–2 mL/kg/hr
  • 3rd space loss requirement = 1–2 mL/kg/hr
  • Patient weight = 50 kg

2 × 50

4 × 50

The answer is 100–200 mL/hr.