Neonatal Nurse Practitioner Practice Exam

How is HFOV rate expressed?

1. Frequency

2. Cycles per minute

3. Respiratory rate

4. Minute volume

The correct answer is: Frequency

High-Frequency Oscillatory Ventilation (HFOV) rate is primarily described in terms of frequency, which is the number of oscillations or breaths delivered per minute. In HFOV, a high frequency is used, typically ranging from 3 to 15 hertz (Hz), which correlates with cycles per second. This mode of ventilation is particularly useful in neonatal care for infants with conditions such as meconium aspiration syndrome or acute respiratory distress as it allows for minimal lung injury while maintaining adequate gas exchange. Using frequency to express the HFOV rate is crucial because it reflects how rapidly the ventilator is generating airflows, leading to effective ventilation without causing trauma to the immature lungs. It emphasizes the unique aspect of HFOV, which distinguishes it from traditional mechanical ventilation modes that are often described in terms of respiratory rate or tidal volume. While cycles per minute may seem like a suitable descriptor since it is related to frequency, stating frequency directly is more precise, particularly in a clinical context where oscillatory patterns are significantly different from conventional respiratory methods. Minute volume and respiratory rate are more commonly associated with standard ventilation techniques, where tidal volume and breaths per minute are discussed, making them less relevant in this specific setting of HFOV.