ISSUES AND INNOVATIONS IN NURSING PRACTICE Estimating core temperature in infants and children after cardiac surgery: a comparison of six methods Fiona J. C. Maxton RN RSCN MsN Doctoral Candidate, Paediatric Intensive Care Unit, The Children’s Hospital at Westmead; and University of Western Sydney, Sydney, New South Wales, Australia Linda Justin RN RSCN BN Clinical Practice Improvement Coordinator, Service Improvement Unit, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia and Donna Gillies BAppSc PhD Head, Research Development Unit, School of Nursing, Family and Community Health, University of Western Sydney, Sydney, New South Wales, Australia Submitted for publication 28 May 2003 Accepted for publication 29 July 2003 Correspondence: Fiona Maxton, 1 Zatopek Avenue, Newington, NSW 2127, Australia. E-mail: maxtonfj@onaustralia.com.au MAXTON F.J.C., JUSTIN L. & GILLIES D. (2004) MAXTON F.J.C., JUSTIN L. & GILLIES D. (2004) Journal of Advanced Nursing 45(2), 214–222 Estimating core temperature in infants and children after cardiac surgery: a com- parison of six methods Background. Monitoring temperature in critically ill children is an important component of care, yet the accuracy of methods is often questioned. Temperature measured in the pulmonary artery is considered the ‘gold standard’, but this route is unsuitable for the majority of patients. An accurate, reliable and less invasive method is, however, yet to be established in paediatric intensive care work. Aim. To determine which site most closely reflects core temperature in babies and children following cardiac surgery, by comparing pulmonary artery temperature to the temperature measured at rectal, bladder, nasopharyngeal, axillary and tympanic sites. Method. A convenience sample of 19 postoperative cardiac patients was studied. Interventions. Temperature was recorded as a continuous measurement from pul- monary artery, rectal, nasopharyngeal and bladder sites. Axillary and tympanic temperatures were recorded at 30 minute intervals for 6 1/2 hours postoperatively. Study limitations. The small sample size of 19 infants and children limits the gener- alizability of the study. Results. Repeated measures analysis of variance demonstrated no significant differ- ence between pulmonary artery and bladder temperatures, and pulmonary artery and nasopharyngeal temperatures. Intraclass correlation showed that agreement was greatest between pulmonary artery temperature and temperature measured by bladder catheter. There was a significant difference between pulmonary artery temperature and temperature measured at rectal, tympanic and pulmonary artery and axillary sites. Repeated measures analysis showed a significant lag between pulmonary artery and rectal temperature of between 0 and 150 minutes after the 6-hour measurement period. Conclusions. In this study, bladder temperature was shown to be the best estimate of pulmonary artery temperature, closely followed by the temperature measured by 214 Ó 2004 Blackwell Publishing Ltd