The reservoir of a pre-filled (disposable) bubble humidifier has 10 mL of water remaining. It would be most appropriate for the neonatal/pediatric specialist to

• A. Refill the reservoir with sterile distilled water
• B. Replace the humidifier setup
• C. Refill the reservoir with sterile tap water
• D. Continue running the humidifier until the reservoir is empty

Answer: (B)

Disposable bubble humidifiers are intended for single-use. When the reservoir has only a small amount of water left, the safest and most effective step is to replace the entire humidifier setup. This maintains a sterile circuit and ensures the device delivers humidity as designed without risking contamination, mineral buildup, or compromising the unit’s performance through refilling. Refilling with any water—even sterile options—goes against the disposable device’s use guidelines and can introduce contaminants or disrupt the sterile pathway. Continuing to run the unit until it’s empty risks inadequate humidification and potential airway irritation or infection. Therefore, replacing the humidifier satisfies both sterility and proper humidification needs.