Hotline Lessons
#5: Humidifier Temperature Settings

One of our Regional Clinical Specialists visited a NICU recently and observed a great deal of water pooling in the Jet circuit. He pressed the SET button in the humidifier panel and noticed that both the Circuit and Cartridge temperatures were set at 40 degrees. He took the opportunity to teach the NICU clinicians about proper Life Pulse humidifier temperature settings.

Humidification on the Life Pulse may need to be adjusted for different environmental conditions.

Where is the patient’s bed relative to air conditioning or heating vents, doorways, traffic patterns?

Is the patient in an open intensive care bed or a closed bed?

The humidifier is programmed so that the circuit (air) temperature is set at 40 degrees C and the cartridge (water) temperature is set at 38 degrees C. In many situations these setting work fine, but that doesn't mean they are always appropriate.

The Circuit temperature should always remain at 40 degrees because the gas temperature cools as it accelerates through the patient box and the LifePort adapter; we know from our testing that the delivered temperature at the ET tube is 37 degree C or less.

The Cartridge temperature may need to be adjusted to control humidity and minimize rain-out. If you encounter excessive rainout, the first step is to lower the temperature one degree, clear the excess water from the Life Pulse circuit and wait 20-30 minutes to see if the situation improves. If it does not, drop the cartridge temperature 0.5 degrees and repeat the process.

Your goal is to have the clear portion of the circuit between the humidifier and the patient box dry (small packs of mist or fog are okay, but not droplets) and the green portion between the patient box and the patient covered in mist, so that if you tapped the circuit, droplets would immediately form. We can help you with this process over the hotline, 800-800-4358.

Water droplets that get pushed through the LifePort adapter from the Life Pulse circuit or secretions that come up and out of the patient’s ET tube cause fluctuations in the monitored pressures. The PIP drops and the PEEP rises simultaneously, causing the delta pressure to be very small. Once the moisture moves through the LifePort, the displayed pressures move back--the PIP rises and the PEEP drops. This action is characteristic of moisture interference. If the patient is causing the pressure to fluctuate, it is usually isolated to the PIP dropping with the PEEP staying relatively constant.

If the patient on the Life Pulse is in a closed-style ICU bed (Giraffe style), the easiest way to control over-humidification is to put as much of the Life Pulse circuit inside the closed hood as possible. The shorter the portion of the circuit is outside the bed, the less rainout will occur.

Finally, replace the breathing circuit if one of the following occurs:

- A Circuit Low Temp activates unexpectedly and the low temperature condition is not resolved within 5 minutes after following appropriate troubleshooting

- The measured circuit temperature is noted to be below the set temperature for more than 5 minutes

Hotline Archive:

# 1: Humidifier Alarms

# 2: Ready Light

# 3: Troubleshooting - A Systematic Approach

# 4: Should I change the circuit?

# 5: Humidifier Temperature Settings