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The authors have assembled a compilation of exposure rate constants, ƒ-factors, and lead shielding thicknesses for more than 1,100 radionuclides described in ICRP Publication 107. Physical data were taken from well established reference sources for mass-energy absorption coefficients in air, attenuation coefficients, and buildup factors in lead and other variables.The data agreed favorably for the most part with those of other investigators; thus this compilation provides an up-to-date and sizeable database of these data, which are of interest to many for routine calculations. Emissions were also segregated by emitting nuclide, and decay product emissions were emitted from the calculated coefficients, thus for the first time providing for the calculation of exposure rates from arbitrary mixtures of nuclides in arbitrary equilibrium states.

Moderate hypothermia is often used for cerebral protection during anesthesia for cerebral aneurysm clipping. No reliable, rapid, and practical noncardiopulmonary bypass methods for the induction of hypothermia to core temperatures ,34°C have been reported. We assessed the effects of IV administration of chilled 5% albumin (5 mL/kg at 1‐ 6°C) on core temperature after surface cooling to approximately 34°C. We calculated thermal distribution volume from the change in core temperature after the chilled fluid infusions. We also compared rapid administration (5 mL/kg over 30 min) with very rapid administration (5 mL/kg over 3‐5 min). Chilled albumin 5 mL/kg infused over 5 min reduced core temperature by 0.6 6 0.1°C. The same volume of chilled albumin infused over 30 min reduced core temperature by 0.4 6 0.1°C. The calculated thermal distribution volume was less than one third of total body volume. Because the thermal distribution volume in these hypothermic patients was much lower than total body volume, the chilled IV fluids in this study were 3 times more effective in inducing hypothermia than suggested by a simple calculation. To achieve maximal effectiveness, however, chilled fluids must be administered very rapidly (.100 mL/min) to avoid heat gains in standard IV tubing that occur even with rapid administration. Implications: Chilled IV fluids can be much more effective for the induction of hypothermia than commonly assumed, but they must be administered very rapidly to avoid heat gains in IV tubing. (Anesth Analg 1999;89:163‐9)

This is an uncommon article for a modern scientific journal in that it contains no data, it is written in the first person, and it recounts only the personal experiences of a clinical neurosurgeon about the evolution of neurosurgery, anesthesiology, and neuroanesthesiology in Philadelphia from 1939 to 1988, when the surgeon retired from the operating room. The surgeon, Fred Murtagh, practiced neurosurgery during an extraordinarily formative time for American medicine and neurosurgery. He was on the faculty of Temple University for many years and currently is Emeritus Professor of Neurosurgery at the University of Pennsylvania. His observations are from the point of view of a man who has been in the operating room continuously since the early 1940s grappling with the practical problems confronting the neurosurgeon. In addition, he is a highly observant individual and considered by many to be an extraordinary teacher. With respect to the genesis of this article, the neuroanesthesia group at the University of Pennsylvania invited Dr. Murtagh to one of their monthly meetings. A tape recorder was placed in front of him and we were privileged to listen to 2 h of reminiscence about his career and relationships between anesthesiologists and neurosurgeons. Over a several year period, Fred Murtagh and D. S. Smith extracted that tape and wrote the following article. It is my belief that this article, despite its unorthodox format, contains observations of import to clinicians in general and to those who practice the subspecialty of neurosurgical anesthesia.

Changes in the electroencephalogram (EEG), mean arterial blood pressure (MABP), and hemoglobin saturation in brain vasculature of lightly anesthetized normothermic humans undergoing induced circulatory arrest for implantation of an automatic internal cardioverting defibrillator were studied. EEG was measured using a four-channel bipolar montage and hemoglobin saturation was measured transcranially using reflectance spectroscopy at 760 nm with an isosbestic reference at 800 nm. Hemoglobin saturation of blood in the quadriceps muscle was also measured. Thirty-two episodes of hypotension due to ventricular fibrillation were studied along with 31 episodes of hypotension related to ventricular tachycardia and rapid ventricular pacing. In a typical fibrillatory event there was a decrease in MABP followed almost immediately by changes in hemoglobin saturation of blood in the brain vasculature. The first changes in EEG were detected an average of 6.5 s (P less than 0.001, paired t test) after the beginning of change of brain vascular hemoglobin. In some cases changes in hemoglobin saturation could be detected without changes in EEG. Desaturation curves from muscle and brain were significantly different, suggesting that the brain probe was measuring hemoglobin change in a rapidly metabolizing volume of tissue that was dissimilar to the skin, muscle, and bone monitored by the probe over the quadriceps muscle. Examination of the 32 episodes of circulatory arrest revealed a marked response that began immediately with recirculation characterized by an increase of the hemoglobin saturation signal from brain vasculature to above baseline as the duration of circulatory arrest exceeded 37 s, this response is termed reperfusion hyperoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Context.—Preemptive analgesia can decrease the sensitization of the central nervous system that would ordinarily amplify subsequent nociceptive input, but a clear demonstration of its clinical efficacy is necessary for it to become a routine component of acute pain therapy.Objective.—To determine the impact of preemptive epidural analgesia on postoperative pain and other clinically important outcome variables after radical retropubic prostatectomy.Design and Setting.—A block randomized double-blind clinical trial lasting 20 months at a single academic medical center.Patients.—A total of 100 generally healthy and neurologically intact patients scheduled for radical retropubic prostatectomy for the treatment of prostate cancer in whom an epidural catheter for treating postoperative pain was to be placed prior to the induction of general anesthesia.Interventions.—Epidural bupivacaine, epidural fentanyl, or no epidural drug was administered prior to induction of anesthesia and throughout the entire operation, followed by aggressive postoperative epidural analgesia for all patients.Main Outcome Measures.—Daily pain scores during hospitalization and pain scores obtained 3.5, 5.5, and 9.5 weeks after hospital discharge.Results.—The patients who received epidural fentanyl or bupivacaine prior to surgical incision (preemptive analgesia) experienced 33% less pain while hospitalized (P=.007). Pain scores in those receiving preemptive analgesia were significantly lower at 9.5 weeks (P=.02), but were not significantly different at 3.5 or 5.5 weeks. At 9.5 weeks, 32 (86%) of 37 patients receiving preemptive analgesia were pain-free compared with 9 (47%) of 19 control patients (P=.004). Patients receiving preemptive analgesia were more active 3.5 weeks after surgery (P=.01), but not at 5.5 or 9.5 weeks.Conclusions.—Even in the presence of aggressive postoperative pain management, preemptive epidural analgesia significantly decreases postoperative pain during hospitalization and long after discharge, and is associated with increased activity levels after discharge.

Brain metabolism cerebral and spinal cord blood flow pathophysiology of metabolic brain injury cerebrospinal fluid intracranial pressure the blood brain carrier and cerebral oedema cerebral blood flow, metabolism and intracranial pressure neuroradiology neurophysiologic brain monitoring - evoked potentials neurophysiologic brain monitoring - electroencephalography intraoperative fluid management during craniotomy care of the acutely unstable patient superatentorial masses - surgical considerations superatentorial masses - anesthetic considerations the posterior fossa - surgical considerations the posterior fossa - anesthetic considerations cerebral aneurysms and arterio-venous malformations - surgical considerations cerbral aneurysms - anaesthetic considerations interventional neuroradiology and the anaesthetic management of patients with arterio-venous malformations induced hypertension anaesthesia management of patients undergoing neuroradiologic procedures anaesthetic management of patients undergoing blood brain barrier disruption occlusive cerebrovascular disease - medical and surgical considerations occlusive cerebrovascular disease - anaesthetic considerations anaesthesia for patients undergoing surgery for seizures anaesthesia for paediatric neurosurgery neurosurgical diseases of the spine and spinal cord - surgical considerations neurosurgical diseases of the spine and spinal cord - anaesthetic considerations anaesthetic considerations in patients with neuroendocrine disease post-operative and intensive care management of severe head injury multi-system sequelae of severe head injury spinal cord injury brain death ethical considerations in the care of patients with neurosurgical disease.