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Estimating core temperature in infants and children after cardiac surgery: a comparison of six methods
Fiona J C Maxton1, Linda Justin, Donna Gillies
1Paediatric Intensive Care Unit, The Children's Hospital at Westmead, University of Western Sydney, Sydney, New South Wales, Australia. maxtonfi@onaustralia.com.au
Insights
Bladder and nasopharyngeal temperature monitoring closely estimate pulmonary artery core temperature in critically ill children after cardiac surgery. These methods offer reliable alternatives to less invasive temperature measurement techniques.
Area of Science:
- Pediatric Critical Care Medicine
- Cardiovascular Surgery Monitoring
- Thermoregulation in Infants and Children
Background:
- Accurate temperature monitoring is crucial for critically ill children, but current methods often lack precision.
- Pulmonary artery temperature is the gold standard but invasive and unsuitable for most patients.
- A reliable, less invasive core temperature measurement is needed in pediatric intensive care.
Purpose of the Study:
- To compare the accuracy of various temperature monitoring sites against pulmonary artery temperature in pediatric cardiac surgery patients.
- To identify the most reliable non-pulmonary artery site for core temperature assessment post-cardiac surgery.
Main Methods:
- A convenience sample of 19 pediatric patients undergoing cardiac surgery was studied.
- Continuous temperature measurements were taken from pulmonary artery, rectal, nasopharyngeal, and bladder sites.
- Axillary and tympanic temperatures were recorded at 30-minute intervals for 6.5 hours post-operation.
Main Results:
- Bladder temperature showed the greatest agreement with pulmonary artery temperature.
- Nasopharyngeal temperature also demonstrated good agreement with pulmonary artery temperature.
- Significant differences and delays were observed between pulmonary artery temperature and rectal, axillary, and tympanic measurements.
Conclusions:
- Bladder temperature is the best estimate of pulmonary artery temperature in this population.
- Nasopharyngeal temperature is a close second, supporting its use.
- Bladder or nasopharyngeal catheters are recommended for temperature monitoring in critically ill children post-cardiac surgery.
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 pulmonary 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 generalizability of the study.
Results:
Repeated measures analysis of variance demonstrated no significant difference 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 nasopharyngeal probe. The results support the use of bladder or nasopharyngeal catheters to monitor temperature in critically ill children after cardiac surgery.
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