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991.
C. F. Wallroth PhD K. -L. Gippert PhD M. Ryschka PhD W. Falb MSc H. -D. Hattendorff PhD B. Schramm PhD R. Torge PhD K. H. Mahrt PhD W. Kroebel PhD Dr. D. Westenskow PhD 《Journal of clinical monitoring and computing》1995,11(3):168-174
Objective. The objective of our study was to establish the refractive indices and the virial coefficients of the volatile anesthetic vapors. These indices and coefficients will allow refractometry to be used by manufacturers to produce accurate calibration, without requiring expensive high-precision calibration gases.Methods. We used a precision refractometer to measure the refractive indices for five volatile anesthetic vapors. We prepared our calibration gases by mixing a gravimetrically calibrated amount of liquid agent with a constant gas flow.Results. The refractive indices for the volatile anesthetic vapors are 1,603.2 for halothane, 1,540.4 for enflurane, 1,563.3 for isoflurance, 1,538.3 for sevoflurane, and 1,211.7 for desflurane. The maximum theoretical error in our measurements, due to all sensors and all uncertainty in our measurement of apparatus and physical constants, is ±0.56% of the reading (±0.70% for desflurane).Conclusions. If refractometry replaced calibration gases in cylinders, as a calibration standard, manufacturers might avoid errors that now occur because calibration gases manufactured by numerous companies seem to differ. We propose that our values serve as an interim database. 相似文献
992.
993.
K Booth BSc MSc PhD RGN RHV P M Maguire BA MB Bchir FRC Psych DPM T Butterworth MSc PhD RGN RMN RNT DN V F Hiller BSc PhD MSc 《Journal of advanced nursing》1996,24(3):522-527
A prospective study of the impact of training 41 hospice nurses in assessment skills was used to test hypotheses that blocking behaviours would be used more when patients disclosed feelings and used less when nurses perceived that they had satisfactory professional support Each nurse was asked to assess a patient's current problems before and after feedback training and 8 months later Audiotape recordings of these interviews were rated by trained raters They determined the frequency of nurses' responses which had the function of blocking patient disclosure and the emotional level of patient disclosure Before each patient assessment each nurse was interviewed and questionnaires administered to measure her perceptions of the support she received Blocking behaviours were most evident when patients disclosed their feelings (Kendalls r=0 36, P < 0 001) In interviews containing most patient disclosure of feeling, blocking was significantly less (r= - 0 24, P < 0 5) when the nurse felt that practical help would be available if needed and when the nurse felt that her direct supervisor was concerned about the nurse's own welfare (r= -0 37, P < 0 005) 相似文献
994.
995.
996.
Olivier Verdonck MD Sean J. Reed MSc Jeffery Hall MD Jean Gotman PhD Gilles Plourde MD 《Journal canadien d'anesthésie》2014,61(3):254-262
Purpose
Brain imaging studies suggest that loss of consciousness induced by general anesthetics is associated with impairment of thalamic function. There is, however, limited information on the time course of these changes. We recently obtained intracranial electroencephalogram (EEG) recordings from the ventroposterolateral (VPL) nucleus of the thalamus and from the motor cortex during induction of anesthesia in three patients to study the time course of the alterations of cortical and thalamic function.Clinical features
The patients were American Society of Anesthesiologists physical status I-II males aged 33-57 yr with intractable central pain caused by brachial plexus injury (patient 1 and 2) or insular infarct (patient 3). Anesthesia was induced with propofol (2.5-3.1 mg·kg?1 over 30-45 sec) followed, after loss of consciousness, by rocuronium for tracheal intubation. The data retained for analysis are from one minute before the start of propofol to 110 sec later during ventilation of the patients’ lungs before tracheal intubation. Spectral analysis was used to measure absolute EEG power. Propofol caused significant increases of cortical and thalamic power in the delta to beta frequency bands (1-30 Hz). These increases of cortical and thalamic power occurred either concomitantly or within seconds of each other. Propofol also caused a decrease in cortical and thalamic high-gamma (62-200 Hz) power that also followed a similar time course.Conclusion
We conclude that induction of anesthesia with propofol in these patients was associated with concurrent alterations of cortical and sensory thalamic activity. 相似文献997.
Elizabeth van Veen-Berkx MSc Justin Bitter MSc Sylvia G. Elkhuizen PhD Wolfgang F. Buhre MD PhD Cor J. Kalkman MD PhD Hein G. Gooszen MD PhD Geert Kazemier MD PhD 《Journal canadien d'anesthésie》2014,61(6):524-532
Background
Predicting total procedure time (TPT) entails several elements subject to variability, including the two main components: surgeon-controlled time (SCT) and anesthesia-controlled time (ACT). This study explores the effect of ACT on TPT as a proportion of TPT as opposed to a fixed number of minutes. The goal is to enhance the prediction of TPT and improve operating room scheduling.Methods
Data from six university medical centres (UMCs) over seven consecutive years (2005-2011) were included, comprising 330,258 inpatient elective surgical cases. Based on the actual ACT and SCT, the revised prediction of TPT was determined as SCT × 1.33. Differences between actual and predicted total procedure times were calculated for the two methods of prediction.Results
The predictability of TPT improved when the scheduling of procedures was based on predicting ACT as a proportion of SCT.Conclusions
Efficient operating room (OR) management demands the accurate prediction of the times needed for all components of care, including SCT and ACT, for each surgical procedure. Supported by an extensive dataset from six UMCs, we advise grossing up the SCT by 33% to account for ACT (revised prediction of TPT = SCT × 1.33), rather than employing a methodology for predicting ACT based on a fixed number of minutes. This recommendation will improve OR scheduling, which could result in reducing overutilized OR time and the number of case cancellations and could lead to more efficient use of limited OR resources. 相似文献998.
999.
Jamie E. Collins PhD Benjamin N. Rome Meghan E. Daigle Vladislav LernerJeffrey N. Katz MD MSc Elena Losina 《The Journal of arthroplasty》2014
Range of motion (ROM) is an important component of the assessment of total knee arthroplasty (TKA) outcome. We compared patient-reported versus clinically observed ROM in a prospective cohort. Clinically observed ROM was measured using a goniometer by a trained research assistant. Self-reported ROM was estimated using a set of lateral knee photographs depicting varying levels of flexion and extension. All measures were taken pre-operatively, three, and six months postoperatively. We found statistically significant associations between self-reported ROM and clinically observed ROM for flexion and extension (all P < 0.001). We dichotomized flexion at 90° and found that self-report had a specificity of 94% and sensitivity of 65%. We conclude that patient-reported ROM may be a useful outcome measure for TKA. 相似文献