Evaluation of a new paediatric scavenging valve

Prolonged exposure to anaesthetic gases may be associated with adverse effects. Scavenging is in widespread use in adult anaesthesia but it has been more difficult to find a satisfactory solution for use in paediatric anaesthesia. The Exeter Paediatric T-piece Scavenging (Exeter PTS) valve has been designed for use with a modified Jackson-Rees system to allow connection to an active or passive Approved Gas Scavenging System.

Use of the Exeter PTS valve was evaluated in 35 spontaneously breathing paediatric patients (mean age 4.7 years, mean weight 16.7 kg) using each patient as their own control. Atmospheric pollution was measured using a Miran 1B infrared spectrophotometer.

When using a modified Jackson-Rees breathing system with an open-ended bag, pollution levels of isoflurane exceeded the Occupational Exposure Standard of 50 p.p.m. When the Exeter PTS valve and an active scavenging system were used, pollution was significantly reduced to below 5% of the recommended limit.

We conclude that there is a need to reduce atmospheric pollution when using a modified Jackson-Rees system in spontaneously breathing patients and that this can be achieved by use of the Exeter PTS valve.