Question
What tidal volume does PALICC 2 recommend for pediatric patients requiring mechanical ventilation?
Answer
PALICC 1 recommended a tidal volume (VT) of 5 to 8 mL/kg for patients with better respiratory system compliance, and 3 to 6 mL/kg for those with poor compliance. PALICC 2 updated this guidance based on a rigorous review of the evidence.
A landmark 1998 study by Amato and colleagues compared conventional ventilation using a VT of 12 mL/kg against a more protective strategy with a VT of 6 mL/kg. Patients on 12 mL/kg had a survival rate of approximately 28 percent. Those on 6 mL/kg had a survival rate of approximately 60 percent, demonstrating clearly that protective ventilation saves lives.
A subsequent multicenter randomized controlled trial by Dr. Khemani and colleagues found that 6 to 8 mL/kg produced the highest survival rates. Dropping below 6 mL/kg was associated with worse outcomes, possibly due to inadequate alveolar ventilation.
PALICC 2 revised the tidal volume recommendation to 6 to 8 mL/kg, with strong agreement at 98 percent. For patients in whom these volumes would cause plateau or driving pressures to exceed recommended limits, a VT less than 6 mL/kg should be used. In the most severely ill patients where survival is the primary concern, VT less than 4 mL/kg may be used with caution.
This Ask the Expert is an edited excerpt from the course, An RT Overview of the Revised PARDS Guidelines from PALICC II, presented by Evan Richards, BSc, RT.
