Acta anaesthesiologica Scandinavica. Supplementum
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Acta Anaesthesiol Scand Suppl · Jan 1975
Influence of changes in arterial PCO2 on cerebral blood flow and cerebral energy state during hypothermia in the rat.
In order to study the relationship between arterial PCO2 and cerebral blood flow (CBF) in hypothermia, the body temperature of artifically ventilated rats was decreased to 22 degreesC, and changes in CBF were evaluated from arteriovenous differences in oxygen content (AVDO2) at PaCO2 values of 15, 30, 40 and 60 mm Hg. The results were compared to those obtained at normal body temperature (37 degrees C) over the PaCO2 range 15-60 mm Hg. Separate experiments were performed to evaluate CBF and CMRO2 at 22 degrees C and a PaCO2 of 15 mm Hg, using an inert gas technique for CBF. ⋯ However, with a decrease in PaCO2 the reduction in CBF was much more pronounced in hypothermia, and at PaCO2 15 Mm Hg CBF was less then 20% of the value measured in normothermic and normocapnic animals. The results of the metabolite measurements gave no evidence of tissue hypoxia in spite of the pronounced reduction in CBF. Although the results demonstrate that the brain of a hypothermic animal is protected against the harmful effects of a lowered CBF, it may not warrant recommending hyperventilation in clinical cases of hypothermia, especially not in patients with arteriosclerosis or cerebrovascular diseases.
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Acta Anaesthesiol Scand Suppl · Jan 1975
Comparative StudyThe effect of anesthesia on intraoperative and postoperative bleeding during abdominal prostatectomies: a comparison of neurolept anesthesia, halothane anesthesia and epidural anesthesia.
Intraoperative blood loss was measured during abdominal prostatectomies in 213 patients anesthetized with neurolept anesthesia, halothane anesthesia and epidural anesthesia. In 55 of these patients, postoperative bleeding was also measured. The average intraoperative blood loss with neurolept anesthesia was 8.2 +/- 5 ml/min, with halothane anesthesia 6.6 +/- 6.3 ml/min and with epidural anesthesia 3.8 +/- 2.3 ml/min. ⋯ Statistical analyses failed, however, to show a significant correlation between blood pressures and blood loss in the individual patient. Thus, the ultimate explanation for the diminished bleeding associated with epidural anesthesia is not definitely ascertained. The average postoperative bleeding was not significantly different among the three anesthetic groups.