ABSTRACT
OBJECTIVE: End-tidal partial pressure of carbon dioxide(PETCO2) is often used as an estimate of arterial partial pressure of carbon dioxide(PaCO2), with the understanding that PaCO2 usually exceeds PETCO2. During craniotomies, because hyperventilation is used to therapeutically lower intracranial pressure, the difference between arterial and end-tidal partial pressure of carbon dioxide(P(a-ET)CO2) has therapeutic implications. To determine how much information concerning neurosurgical operation and clinical outcome is provided by the PETCO2, PaCO2 and P(a-ET)CO2 during surgery, we evaluated 81 patients who had neurosurgical operation. METHODS: There were 51 males and 30 females with a mean age of 50.3 years(range 7-85 years). After the induction of general anesthesia, body temperature was maintained in a normothermia, endtidal CO2 was maintained 28-34mmHg and the systolic blood pressure was kept 90-120mmHg. ETCO2, PaCO2 and regional cortical blood flow(rCoBF) were checked at the time of dura closure. Neurologic outcome was evaluated at 8 hours after operation to rule out other factors which may influence on the patient's long-term outcome. Data were collected and compared by student's t-test or chi-square analysis. RESULTS: The PaCO2 was 34.6+/-5.2mmHg(range, 24.9-54.8), PETCO2 was 29.9+/-4.1mmHg(range, 20.0-45.0) and P(a-ET)CO2 was 4.7+/-3.5mmHg(range, -1.1-18.6). The correlation between the PaCO2 and PETCO2 was statistically significant(PETCO2=13.3-0.57xPaCO2). But there was no correlation of rCoBF with PaCO2 and ETCO2. P(a-ET)CO2 values less than 8mmHg were correlated well with good neurologic outcome compared with higher P(a-ET)CO2 patients. PaCO2, rCoBF, mean arterial blood pressure, arterial pH and initial Glasgow coma scale showed statistically significant correlation with neurologic outcome(p<0.05). CONCLUSION: Based on our study, P(a-ET)CO2 value could be used as a good prognostic factor during the neurosurgical operation and anesthesiologist should be tried to decrease this value. And in patients who has a intact brain autoregulation, rCoBF was not influenced by PaCO2 and ETCO2, entirely.
Subject(s)
Female , Humans , Male , Anesthesia, General , Arterial Pressure , Blood Pressure , Body Temperature , Brain , Carbon Dioxide , Carbon , Craniotomy , Glasgow Coma Scale , Homeostasis , Hydrogen-Ion Concentration , Hyperventilation , Intracranial Pressure , Partial PressureABSTRACT
OBJECTIVE: The brain temperature is about 0.4-1 degrees C higher than that of the other peripheral body area. But most of these results have been obtained in normothermic condition. The objective of this study is to evaluate the temperature difference between the brain and axilla, in patients under hypothermia. METHODS: Sixty-three patients(37 women and 26 men) who underwent craniotomy with implantation of the thermal diffusion flowmetry sensor were included in this study. The temperature of the cerebral cortex and axilla was measured every 2 hours, simultaneously. The patient group was divided according to axillary temperature hyperthermia(over 38 degrees C), normothermia(36-38 degrees C) and hypothermia(under 36 degrees C). Total 1671 paired sample data were collected and analyzed. RESULTS: The temperature difference between the cerebral cortex and the axilla was 0.45+/-1.04 degrees C in hyperthermic patients, 0.97+/-1.1 degrees C in normothermic patients and 1.04+/-0.81 degrees C in hypothermic patients. The temperature difference has statistical significance in each group(unpaired t-test, p<0.05). CONCLUSION: From our study the temperature difference between the brain and the axilla in hypothermic condition increased more than that of normothermic state. And in hyperthermic condition, the temperature difference decreased.
Subject(s)
Female , Humans , Axilla , Brain , Cerebral Cortex , Craniotomy , Fever , Hypothermia , Rheology , Thermal DiffusionABSTRACT
No abstract available.