Patient monitoring during and after open heart surgery by an improved deep body thermometer

The deep body thermometer developed by Fox was improved by Togawa by thermal insulation of the probe. The present status of medical progress in clinical thermometry through the improved deep body thermometer was reviewed from the view point of cardiac surgery. The forehead and sole temperatures obtained by this improved thermometer were monitored and recorded by a multipotentiometric recorder continuously up to 12 days in the patients admitted to the ICU who underwent open heart surgery. The forehead tissue temperature measured by this thermometer is slightly lower than and parallel to the rectal temperature, being close to the pulmonary arterial blood temperature. On the other hand, the sole tissue temperature fluctuates from room temperature to the forehead tissue temperature, sometimes showing rhythmic changes. The former seems to be the core temperature and the latter, the shell temperature. The dissociation when the two temperatures are more than 7 degrees C apart from each other suggests that the hemodynamical condition is worse than in the convergence when they remain within 2 degrees C. A state of shock can be diagnosed when the arterial systolic pressure is less than 90 mmHg and the urine output less than 1 ml/min/mg in addition to the dissociation. The effect of treatment and the prognosis for the patient are predictable according to the trends of the two temperatures as divergent or convergent. The dynamic thermometry by this thermometer is very informative and the procedure is noninvasive without discomfort to the patient.