23/08/2026
CLINICAL FOCUS:
Fixed vs. Variable Oxygen Delivery
When managing acute respiratory distress, choosing between a low-flow and a high-flow delivery system directly impacts patient outcome and gas exchange stability:
Low-Flow Systems (Nasal Cannula, Simple Face Masks): Deliver oxygen below the patient's inspiratory flow rate. The delivered fraction of inspired oxygen (FiO_2) varies continuously depending on the patient's respiratory rate and tidal volume.
High-Flow Systems (Venturi Masks, Venturi Valves): Deliver total flow rates that exceed the patient's peak inspiratory demand. By utilizing the Bernoulli principle, high-flow systems provide a precise, predictable FiO_2 regardless of breathing patterns
Clinical Key: For patients with chronic obstructive pulmonary disease (COPD) or hypercapnic respiratory failure, precise FiO_2 control via Venturi valves is essential to avoid suppressing hypoxic drive.
How often do you utilize Venturi systems in your ward or emergency setup? Share your thoughts below. 👇
