Incidence of Artifacts and Deviating Values in Research Data Obtained from an Anesthesia Information Management System in Children

Anaesthesia information management systems (AIMS) are increasingly being used for record keeping and as a resource for database research and medicolegal litigations.  However, the AIMS cannot verify whether a particular value is true or an artefact and so artefacts influence the validity of research based on AIMS.

This was a prospective, observational cohort study of paediatric patients having general anaesthesia for noncardiac paediatric surgical or diagnostic procedures in a tertiary paediatric university hospital in The Netherlands.  Between May and August 2015 one of five operating rooms were randomly assigned and all anaesthetics were observed by a resident anaesthesiologist who had been trained to identify artefacts.  All data for HR, Spo2, ETCO2 and mean NIBP and IBP were collected by the AIMS and the investigator inspected each value and assessed whether it was an artefact or a valid value.  The phase of anaesthesia and causes of artefacts were also documented.  An artefact was defined as any value that was judged invalid and/or not reflecting the patient’s current physiologic state.

136 anaesthetics (10, 236min) were included in this study.  The incidence of artefacts was 0.5% for HR, 1.3% for Spo2, 7.5% for ETCO2, 5% for NIBP and 7.3% for IBP.  Values deviating from a predefined reference range were more often artefacts than values in a normal range.  The incidence of artefacts was higher during the induction and emergence phases compared to the maintenance phase.  This is due to many factors including more patient movement.  Most of the ETCO2 artefacts were related to mask ventilation (higher in younger children who are more likely to have an inhalational induction).  A reasonable number of artefacts were due to errors by the anaesthesiologists.

Take Home Message

This study highlights the potential problems of artefacts in AIMS and that their data is not always valid, especially if it is used for research or medicolegal purposes.

Reviewed by: Naomi Pearson