Infrared Thermometer: an accurate tool for temperature measurement during renal surgery.
OBJECTIVE
To evaluate infrared thermometer (IRT) accuracy compared to standard digital thermometer in measuring kidney temperature during arterial clamping with and without renal cooling.


METHODS
20 pigs weighting 20Kg underwent selective right renal arterial clamping, 10 with (Group 1 - Cold Ischemia with ice slush) and 10 without renal cooling (Group 2 - Warm Ischemia). Arterial clamping was performed without venous clamping. Renal temperature was serially measured following clamping of the main renal artery with the IRT and a digital contact thermometer (DT): immediate after clamping (T0), after 2 (T2), 5 (T5) and 10 minutes (T10). Temperature values were expressed in mean, standard deviation and range for each thermometer. We used the T student test to compare means and considered p < 0.05 to be statistically significant.


RESULTS
In Group 1, mean DT surface temperature decrease was 12.6 ± 4.1°C (5-19°C) while deep DT temperature decrease was 15.8 ± 1.5 °C (15-18 °C). For the IRT, mean temperature decrease was 9.1 ± 3.8 °C (3-14°C). There was no statistically significant difference between thermometers. In Group 2, surface temperature decrease for DT was 2.7 ± 1.8°C (0-4°C) and mean deep temperature decrease was 0.5 ± 1.0 °C (0-3 °C). For IRT, mean temperature decrease was 3.1 ± 1.9°C (0-6°C). No statistically significant difference between thermometers was found at any time point.


CONCLUSIONS
IRT proved to be an accurate non-invasive precise device for renal temperature monitoring during kidney surgery. External ice slush cooling confirmed to be fast and effective at cooling the pig model.
Division of Urology, Clinics Hospital, University of Sao Paulo Medical School, SP, Brazil.
Giovanni Scala
GS
Marchini
Ricardo Jordão
RJ
Duarte
Anuar Ibrahim
AI
Mitre
Bruno Camargo
BC
Tiseo
Valter Dell'acqua
VD
Cassão
Fábio César Miranda
FC
Torricelli
Marco Antonio
MA
Arap
Miguel
M
Srougi
D000818:Animals; D001831:Body Temperature; D050377:Cold Ischemia; D003250:Constriction; D004867:Equipment Design; D007259:Infrared Rays; D007668:Kidney / Q000601:surgery*; D008297:Male; D008488:Medical Illustration; D012016:Reference Values; D015203:Reproducibility of Results; D013499:Surface Properties; D034421:Sus scrofa; D013821:Thermometers / Q000592:standards*; D013997:Time Factors; D052096:Warm Ischemia