Temperature changes of CoolSticks during simulated use

•Vapo-coolant sprays (e.g. ethyl chloride) have substantial environmental impacts.•CoolSticks are a re-usable alternative for block assessment.•We investigated the temperature change of CoolSticks in various conditions.•With passive warming the CoolSticks reached 14.3 °C after 10 min.•In simulated use, the CoolSticks reached 18.9 °C after 10 min. Cold sensation is often used to check neuraxial anaesthesia and analgesia. One opportunity to reduce the carbon footprint of anaesthesia is to replace vapo-coolant sprays such as ethyl chloride with a reusable device called the CoolStick, which is cooled in a refrigerator between uses. We designed a study to investigate how long the CoolStick remains at its working temperature, which we defined as