Flow-controlled ventilation: A systematic review of preclinical and clinical studies.

In 30 seconds

This systematic review synthesized preclinical and clinical studies comparing flow-controlled ventilation (FCV) with conventional ventilation. It included ten preclinical and ten clinical studies, with findings assessed qualitatively because of heterogeneity. Preclinical studies consistently found lower respiratory rate and minute ventilation with FCV while maintaining or improving oxygenation and carbon dioxide control. Clinical results varied, but studies using compliance-guided FCV titration generally reported similar physiological benefits. No consistent adverse hemodynamic effects were reported; certainty in the clinical evidence was low to moderate.

Key findings

• Across ten preclinical studies, FCV consistently reduced respiratory rate and minute ventilation while maintaining or improving oxygenation and carbon dioxide control.
• Of ten clinical studies, six used compliance-guided titration; these generally reported lower respiratory rate and minute ventilation with carbon dioxide control maintained, often alongside improved oxygenation.
• Clinical studies using fixed or protocolized ventilation targets showed more variable physiological effects.
• No consistent adverse hemodynamic effects were reported; clinical evidence certainty was low to moderate.

Why it matters

FCV’s regulation of both inspiration and expiration may affect ventilatory efficiency, gas exchange, and intrathoracic pressures differently from conventional modes. The review suggests potential physiological benefits, particularly when FCV is titrated to compliance, but the heterogeneous and limited clinical evidence means these findings do not establish consistent clinical benefit.

What to keep in mind

Clinical studies were heterogeneous, requiring qualitative synthesis, and the certainty of clinical evidence was low to moderate. The review identifies a need for larger trials and standardized approaches.