Improving Patient Safety

Novel Heat and Moisture Exchanger (HME) visually alerts clinicians to error of dual humidification in mechanical ventilation circuits


  • Novel passive heat and moisture exchanger (HME)
  • Built-in safety engineered temperature-dependent warning system
  • Provides a clear, rapid visual prompt to clinicians of dual humidification error in a ventilation circuit
  • Looks and functions like a standard HME but with added safety feature
  • Enables clinicians to positively manage the risk of using different airway humidification devices simultaneously

Artificial humidification in ventilated patients

Artificial humidification systems are used with ventilated patients in the operating theatre or intensive care unit to condition medical gases prior to delivery to the patients lower respiratory tract.

This helps to reduce potential harm caused by introducing cold and dry gases to the lower respiratory tract which could lead to complications such as drying of secretions, inflammation and ventilation acquired pneumonia among others.

Commonly used in clinical settings are both heated humidifiers (HH) or passive heat and moisture exchangers (HME), and both are commonly present in the same clinical environments with health workers choosing their preferred option. Local protocols can also co-exist, such as use of HME in short term and HH for longer term ventilated patients.

Potential complications and risks for patients

Complications can arise as HH and HME are not designed to be used simultaneously in the same breathing circuit. When both HH and HME are inadvertently used in the same breathing circuit for a ventilated patient complications can arise. If this occurs and the dual humidification equipment error is not swiftly noticed and rectified it can result in partial or full blockage of the airway with potentially fatal outcomes.

While reporting systems suggest that such occurrences are infrequent at a local level, on a national scale numbers are more significant. In December 2015, the NHS issued a patient safety alert to raise awareness of this risk (1).

HUMIDICARE®: provides an early warning of dual humidification

The novel HUMIDICARE® HME looks and functions like a standard HME but it has a built-in engineered safety solution which activates to visually highlight to clinicians when an error is detected, and the HME is fitted into a breathing circuit which already contains a HH.

A temperature-dependent warning system is triggered when HUMIDICARE® is placed into a warmed circuit containing a HH. A prominent coloured warning appears, visually alerting clinical staff to the equipment error and prompting action to be taken. Importantly, it directs clinical staff to check the equipment in the breathing circuit, something that may not be addressed as an initial potential source of issue when faced with a deteriorating patient.


A recent implementation study using simulated clinical settings has confirmed the proof of principle of HUMIDICARE®(2).

Two simulations, one to determine the temperature activation threshold of HUMIDICARE® and one to assess the efficacy of HUMIDICARE® in a simulated breathing circuit, demonstrated that the device performs reliably and consistently as a rapid early warning system.

HUMIDICARE® provides healthcare institutions with an approach to proactively managing the potential risks associated with dual humidification as outlined in the national 2015 NHS Patient Safety Alert.

Further Development

Work to make HUMIDICARE® commercially available is ongoing.

Interested in further developments? Keep informed about the progress of HUMIDICARE® - just complete the short form to receive updates direct from Medovate.



(2) Vikesh Patel , Jonathan Dean , Joseph Vayalil Lawrence , Sivarupan
Selvanayagam , Mark C. Blunt & Peter J. Young (2021): Humidicare – an implementation study of a novel HME safety device designed to prevent ventilator circuit occlusion due to inadvertent dual humidification, Journal of Medical Engineering & Technology
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Product Images

HUMIDICARE® - improving patient safety Medovate Managing Director, Stuart Thomson, with a HUMIDICARE® device  [Image Credit: Keith Heppell, Cambridge Independent]

"I feel that HUMIDICARE® will help make everyday clinical practice that little bit safer."

— Dr J M Dean, Anaesthetic Registrar, Sheffield Children's NHS Foundation Trust

"Clinicians typically are reluctant to significantly change their practice especially regarding rare events and the beauty of HUMIDICARE® is that they will not have to, as it fits seamlessly with current practices"

— Dr J M Dean, Anaesthetic Registrar, Sheffield Children's NHS Foundation Trust