Capnography for the veterinary nurse

The confidential enquiry into perioperative small animal fatalities states that small animal anaesthesia appears to be increasing in safety. However, greater patient care during the perianaesthetic period would reduce fatalities further (Brodbelt et al, 2008). While there is no direct evidence to prove that the use of capnography can reduce the risk of mortality, it has been shown to prevent morbidities and has allowed for the early detection of complications before significant physiological side effects are seen (Langton et al, 2010). This confirms Henao-Gurrero et al's (2005) opinion that capnography can improve the anaesthetic management of cases seen. Capnography is becoming more commonplace in the veterinary practice; however, only 37% of registered veterinary nurses questioned felt comfortable with its use (unpublished data).

To understand capnography and the capnogram, there needs to be an understanding of how carbon dioxide (CO₂) is regulated in the body and why it is important. CO₂ in the body is determined by three factors: