Anesthesia and analgesia
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Anesthesia and analgesia · Jul 1982
Oxygen transfer from mother to fetus during cesarean section under epidural anesthesia.
The correlation between maternal PaO2 levels and umbilical vein (UV) and umbilical artery (UA)PO2 levels was studied in 40 healthy patients undergoing elective cesarean sections under lumbar epidural anesthesia. Patients were divided into four equal groups. Each group inhaled oxygen at a FIO2 of 0.21, 0.47, 0.74 (in nitrogen), or 1.0. ⋯ Maternal arterial, UV, and UA base excess values in the hyperoxic groups were significantly higher than in the normoxic groups. There was no difference in 1- or 5-minute Apgar scores between the normoxic and hyperoxic groups. It is concluded that maternal hyperoxia improves fetal oxygen stores and acid-base status during cesarean section under epidural anesthesia.
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Anesthesia and analgesia · Jun 1982
Continuous monitoring of mixed venous oxygen saturation in critically ill patients.
A new pulmonary artery balloon flow-directed catheter combines a fiberoptic photometric system for continuous display of mixed venous blood oxygen saturation (SvO2) with the capacity for hemodynamic measurements including thermodilution cardiac output estimation. This oximetry system was studied to determine its accuracy, reliability, and usefulness in the surgical intensive care unit (ICU). ⋯ The catheter values for SvO2 were closely related (r = 0.9516) to those obtained from a laboratory Co-oximeter. Continuous monitoring of SvO2 is accurate and valuable as a warning system for deterioration in cardiopulmonary function and as an indicator of the effects of various therapeutic maneuvers in critically ill patients.
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Anesthesia and analgesia · Jun 1982
Comparative StudyChanging specialties: do anesthesiologists differ from other physicians?
Career choices of physicians frequently change after senior year in medical school. Although previous studies have documented the magnitude of these changes, they contain no information concerning anesthesiologists. Changes in specialties of 1151 physicians, graduates from the same medical school, between the years 1968 and 1976 were studied. ⋯ Of 31 physicians who planned careers in anesthesiology as seniors, 26 (84%) remained in anesthesiology. Nine physicians changed from other specialties to anesthesiology. The ability of anesthesiology to retain physicians who originally planned to specialize in it, or to gain physicians from other fields, was not different from that found in other specialties studied.
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Anesthesia and analgesia · May 1982
Intracranial hypertension during surgery for supratentorial tumor: correlation with preoperative computed tomography scans.
To test the hypothesis that preoperative head computed tomography scans could be used to predict the likelihood that a patient with a supratentorial brain tumor would develop intracranial hypertension during surgery before the cranium was opened, intraoperative intracranial pressure and blood pressure records of 60 patients undergoing craniotomy were compared with the appearance of their preoperative computed tomography scans. The scans were interpreted by a neuroradiologist who was unaware of the clinical events in each case. ⋯ When preoperative brain edema seen on computed tomography scan was taken into consideration, increases in intracranial pressure during craniotomy also correlated with simultaneous increases in blood pressure. It is concluded that patients with large amounts of preoperative brain edema surrounding supratentorial tumors should be considered at risk for developing intraoperative intracranial hypertension and may benefit from preoperative insertion of an intracranial pressure monitor before general anesthesia is induced.
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The delivery performance of two Fortec vaporizers for isoflurane in oxygen (O2) was evaluated. Isoflurane concentration was measured at a constant O2 flow rate (from 0.75 to 15 L/min) as the vaporizer dial setting was changed over the range of 0% to 5%. At vaporizer dial settings of 2% or less the average delivered isoflurane concentration differed from dial settings by less than 0.25 vol% at all O2 flows. ⋯ Increasing the environmental temperature to 30 degrees C or decreasing it to 15 degrees C increased or decreased, respectively, vaporized output when compared with conditions at 22 degrees C. Little or no effect on vaporizer output was noted with simulated positive pressure ventilation up to a breathing circuit pressure of 25 torr. We conclude the Fortec vaporizer is as efficient in delivering isoflurane in O2 as previous reports have shown the Fluotec Mark III to be in its delivery of halothane.