Effects of the transcutaneous electrode temperature on the accuracy of transcutaneous carbon dioxide tension

TY - JOUR

T1 - Effects of the transcutaneous electrode temperature on the accuracy of transcutaneous carbon dioxide tension

AU - Sørensen, Line C

AU - Brage-Andersen, Lene

AU - Greisen, Gorm

PY - 2011/11

Y1 - 2011/11

N2 - Aim. The harmful effect of hypocapnia on the neonatal brain emphasizes the importance of monitoring arterial carbon dioxide tension (PaCO2). Transcutaneous monitoring of carbon dioxide (tcPCO2) reduces the need for arterial blood sampling. Drawbacks are high electrode temperature causing risks of skin burning. The aim was to determine the accuracy and precision of tcPCO2 at reduced electrode temperature. Methods. Forty newborns (GA 24.9-41.7) were included. Two tc-monitors were applied (TCM4, Radiometer, Copenhagen). Arterial blood gas sampling and monitoring of tcPCO2-level at different electrode temperatures was done simultaneously (39°C, 40°C, 41°C, 42°C, 44°C). Difference of PaCO2 tcPCO2 was expressed as a percentage of the mean. Results. Mean PaCO2 was 5.8kPa [3,2; 7.9]. Bias (PaCO2 tcPCO2) increased from 5% at 44°C to 17% at 39°C, but did not differ significantly between 41°C and 40°C. The precision of the tcPCO2 at each temperature ranged from +710%. After correction for the temperature-dependent overreading, we found increasing PaCO2 tcPCO2 difference with increasing PaCO2, approx. 2% pr. kPa increase of CO 2. Only mild transient erythema was observed. Conclusion. A lower electrode temperature in tcPCO2-monitoring increases systematic overreading of the tc-electrode. However, in very preterm babies, monitoring at 40°C or 41°C is possible provided a bias correction of 12-15% is applied.

AB - Aim. The harmful effect of hypocapnia on the neonatal brain emphasizes the importance of monitoring arterial carbon dioxide tension (PaCO2). Transcutaneous monitoring of carbon dioxide (tcPCO2) reduces the need for arterial blood sampling. Drawbacks are high electrode temperature causing risks of skin burning. The aim was to determine the accuracy and precision of tcPCO2 at reduced electrode temperature. Methods. Forty newborns (GA 24.9-41.7) were included. Two tc-monitors were applied (TCM4, Radiometer, Copenhagen). Arterial blood gas sampling and monitoring of tcPCO2-level at different electrode temperatures was done simultaneously (39°C, 40°C, 41°C, 42°C, 44°C). Difference of PaCO2 tcPCO2 was expressed as a percentage of the mean. Results. Mean PaCO2 was 5.8kPa [3,2; 7.9]. Bias (PaCO2 tcPCO2) increased from 5% at 44°C to 17% at 39°C, but did not differ significantly between 41°C and 40°C. The precision of the tcPCO2 at each temperature ranged from +710%. After correction for the temperature-dependent overreading, we found increasing PaCO2 tcPCO2 difference with increasing PaCO2, approx. 2% pr. kPa increase of CO 2. Only mild transient erythema was observed. Conclusion. A lower electrode temperature in tcPCO2-monitoring increases systematic overreading of the tc-electrode. However, in very preterm babies, monitoring at 40°C or 41°C is possible provided a bias correction of 12-15% is applied.

U2 - http://dx.doi.org/10.3109/00365513.2011.590601

DO - http://dx.doi.org/10.3109/00365513.2011.590601

M3 - Journal article

SN - 0036-5513

VL - 71

SP - 548

EP - 552

JO - Scandinavian Journal of Clinical & Laboratory Investigation

JF - Scandinavian Journal of Clinical & Laboratory Investigation

IS - 7

ER -