Teleflex ConchaTherm Neptune - Humidity Advisory and Pause Time Settings

To set a more negative temperature gradient, press the rain button for each
additional negative degree desired.
Note: A negative or decreased temperature gradient results in a higher relative humidity
( RH) at the proximal patient airway.
Note: A negative temperature gradient increases the potential for rainout within the
heated-wire circuit.
Caution: The ConchaTherm Neptune is designed to deliver a minimum fluid output of
30 mg H
2
O/L at 30º C, under normal operating conditions. (See recommended Flow
Rates on Page 8). Use of positive or "sun" gradient settings in some conditions can
result in humidity outputs at the patient of less than 30mg H
2
O/L at 30º C. Visually
inspect for condensation droplets in the inspiratory circuit after one hour of operation.
To accept the new temperature gradient settings, press the accept button. The
unit will return to warm-up and normal operation. The temperature gradient selected
will be retained in memory.
Note: During normal operation, the temperature gradient LED and buttons are not
displayed.
4. Low Humidity Advisory:
The AARC Clinical Practice Guideline
1
for Humidification during Mechanical Ventilation
states that the humidification method chosen should provide a minimum of 30 mg H
2
O/L of
delivered gas at 30 ºC. The ConchaTherm Neptune is designed to advise the user of low-
humidity conditions (when the humidifier is in the Invasive mode and the set airway
temperature and gradient result in a column temperature equal to or less than 31 ºC). The
humidifier will advise the user of this condition by displaying a flashing proximal patient air-
way temperature in the “Set-Up” or “Confirm Settings” Mode. An audible alarm will not
sound. In order to address this low humidity situation, the user should either increase the
patient airway temperature or move the gradient closer to the Raindrop.
(See instructions in the User Adjustable Operation section.)
Note: Setting a positive gradient may invoke this advisory condition. For example, a
selected airway temperature of 33 ºC and a Gradient setting of +3 ºC would result in a
column temperature of 30 ºC causing the humidifier to invoke the low-humidity advisory.
Note: The Low Humidity Advisory function is not active in the Non-Invasive mode.
5. Pause Time
To view or adjust the set pause time
, press and hold the accept button. The
pause button will illuminate.
22
Figure 11: Negative Temperature Gradient, Display at -3.0°C.
1 Branson, RD, Campbell SC, Chatburn RL, Covington J. AARC Clinical Practice Guideline: Humidification during
Mechanical Ventilation. Respiratory Care 1992; 37:887-890.