Assessing Sedation with Regional Anesthesia: Inter-Rater Agreement on a Modified Wilson Sedation Scale

A valid and reliable means for measuring sedation during regional anesthesia would be valuable for both research and practice. Current methods of monitoring sedation include machine-, patient-, and observer-based assessment. The reliability of machine-based methods is limited at lower levels of sedation, whereas patient-based methods are impractical at higher levels. Observer-based methods offer the best alternative for assessing sedation during regional anesthesia; however, their reliability has not been adequately documented. We examined the interrater reliability of the Wilson sedation scale. Sedation was assessed by pairs of anesthesia care providers in 100 patients undergoing surgical procedures with regional anesthesia. On the basis of the findings, the scale was modified, and 50 additional patients were assessed. The study protocol called for a series of standardized stimuli administered by a research assistant. Raters were blinded to each other’s ratings. Interrater reliability was assessed by using the &kgr; statistic, a measure of actual agreement beyond agreement by chance. When continuing checks on its operationalization and reliability are included, the modified Wilson scale provides a simple and reliable means by which to assess and monitor intraoperative sedation.

[1]  J. Fleiss,et al.  The measurement of interrater agreement , 2004 .

[2]  A. Arroliga,et al.  Interrater reliability of 2 sedation scales in a medical intensive care unit: a preliminary report. , 2001, American journal of critical care : an official publication, American Association of Critical-Care Nurses.

[3]  M. Johnson,et al.  Development of an Intensive Care Unit Bedside Sedation Scale , 2001, The Annals of pharmacotherapy.

[4]  N. Polissar,et al.  Sedation during spinal anesthesia. , 2000, Anesthesiology.

[5]  T. Short,et al.  The sedative and electroencephalographic effects of regional anaesthesia* , 2000, Anaesthesia.

[6]  D. Chittock,et al.  Measuring quality of sedation in adult mechanically ventilated critically ill patients. the Vancouver Interaction and Calmness Scale. Sedation Focus Group. , 2000, Journal of clinical epidemiology.

[7]  G. Kenny,et al.  Safety of patient-maintained propofol sedation using a target-controlled system in healthy volunteers. , 2000, British journal of anaesthesia.

[8]  G. Guyatt,et al.  Using and understanding sedation scoring systems: a systematic review , 2000, Intensive Care Medicine.

[9]  Judith E. Hall,et al.  Sedative, Amnestic, and Analgesic Properties of Small-Dose Dexmedetomidine Infusions , 2000, Anesthesia and analgesia.

[10]  S. Mackenzie,et al.  Should the pre‐sedation Glasgow Coma Scale value be used when calculating Acute Physiology and Chronic Health Evaluation scores for sedated patients? , 2000, Critical care medicine.

[11]  J. Vincent,et al.  The Brussels sedation scale: use of a simple clinical sedation scale can avoid excessive sedation in patients undergoing mechanical ventilation in the intensive care unit. , 1999, British journal of anaesthesia.

[12]  L. Thijs,et al.  Continuous infusion of lorazepam versus medazolam in patients in the intensive care unit: sedation with lorazepam is easier to manage and is more cost-effective. , 1999, Critical care medicine.

[13]  G. Fraser,et al.  Prospective evaluation of the Sedation-Agitation Scale for adult critically ill patients. , 1999, Critical care medicine.

[14]  D R Nerenz,et al.  Motor Activity Assessment Scale: a valid and reliable sedation scale for use with mechanically ventilated patients in an adult surgical intensive care unit. , 1999, Critical care medicine.

[15]  P. White,et al.  Comparative effects of oral clonidine and intravenous esmolol in attenuating the hemodynamic response to epinephrine injection. , 1999, Journal of clinical anesthesia.

[16]  J. Briegel,et al.  Comparison of five sedation scoring systems by means of auditory evoked potentials , 1999, Intensive Care Medicine.

[17]  L. Kearse,et al.  Bispectral Analysis of the Electroencephalogram Predicts Conscious Processing of Information during Propofol Sedation and Hypnosis , 1998, Anesthesiology.

[18]  M. Wattwil,et al.  Propofol sedation and gastric emptying in volunteers , 1998, Acta anaesthesiologica Scandinavica.

[19]  Peter S. Sebel,et al.  Bispectral Analysis Measures Sedation and Memory Effects of Propofol, Midazolam, Isoflurane, and Alfentanil in Healthy Volunteers , 1997, Anesthesiology.

[20]  P. White,et al.  Electroencephalographic Bispectral Index Correlates with Intraoperative Recall and Depth of Propofol-Induced Sedation , 1997, Anesthesia and analgesia.

[21]  P. Glass,et al.  Double-blind, Randomized Comparison of Ondansetron and Intraoperative Propofol to Prevent Postoperative Nausea And Vomiting , 1996, Anesthesiology.

[22]  S. Thorn,et al.  The Influence of Propofol on Vomiting Induced by Apomorphine , 1995, Anesthesia and analgesia.

[23]  T. Short,et al.  Midazolam and flumazenil pharmacokinetics and pharmacodynamics following simultaneous administration to human volunteers , 1994, Acta anaesthesiologica Scandinavica.

[24]  R. Polomano,et al.  Beyond the Ramsay scale: need for a validated measure of sedating drug efficacy in the intensive care unit. , 1994, Critical care medicine.

[25]  C. Pomfrett,et al.  Respiratory sinus arrhythmia: a new, objective sedation score. , 1993, British journal of anaesthesia.

[26]  J. Vercher,et al.  GABA-ergic control of visual perception in healthy volunteers: effects of midazolam, a benzodiazepine, on spatio-temporal contrast sensitivity. , 1993, British journal of clinical pharmacology.

[27]  M. Eckardt,et al.  Specific memory and sedative effects of the benzodiazepine triazolam , 1993, Journal of psychopharmacology.

[28]  N R Webster,et al.  Auditory evoked response and awareness: a study in volunteers at sub-MAC concentrations of isoflurane. , 1992, British journal of anaesthesia.

[29]  C. E. Harris,et al.  Use of propofol by infusion for sedation of patients undergoing haemofiltration Assessment of the effect of haemofiltration on the level of sedation and on blood propofol concentration , 1992 .

[30]  M. J. Klein,et al.  Study of effects of clobazam and lorazepam on memory and cognitive functions in healthy subjects , 1991 .

[31]  D. Chernik,et al.  Validity and Reliability of the Observer's: Assessment of Alertness/Sedation Scale Study with Intravenous Midazolam , 1990, Journal of clinical psychopharmacology.

[32]  C. Doré,et al.  The auditory evoked response as an indicator of awareness. , 1989, British journal of anaesthesia.

[33]  A. Feinstein.  The Evaluation of Consistency , 1987 .

[34]  A. Feinstein.  The Evaluation of Validity , 1987 .

[35]  I. Rampil,et al.  Changes in EEG spectral edge frequency correlate with the hemodynamic response to laryngoscopy and intubation. , 1987, Anesthesiology.

[36]  A. Feinstein,et al.  Clinical biostatistics: LIV. The biostatistics of concordance , 1981 .

[37]  P. Turner,et al.  Some clinical pharmacological studies with terfenadine, a new antihistamine drug. , 1978, British journal of clinical pharmacology.

[38]  J. R. Landis,et al.  The measurement of observer agreement for categorical data. , 1977, Biometrics.

[39]  M. Ramsay,et al.  Controlled Sedation with Alphaxalone-Alphadolone , 1974, British medical journal.

[40]  P. Kroboth,et al.  Pharmacokinetics and pharmacodynamics of alprazolam after oral and IV administration , 2004, Psychopharmacology.

[41]  S. Levander,et al.  Peripheral antihistamine and central sedative effects of three H1-receptor antagonists , 2004, European Journal of Clinical Pharmacology.

[42]  P. Thompson,et al.  A placebo controlled study of flumazenil in bronchoscopic procedures. , 1997, British journal of clinical pharmacology.

[43]  Ian McDowell,et al.  The Theoretical and Technical Foundations of Health Measurement , 1996 .

[44]  I. Grant,et al.  Sedation during spinal anaesthesia: comparison of propofol and midazolam. , 1990, British journal of anaesthesia.

[45]  B Kirshner,et al.  A methodological framework for assessing health indices. , 1985, Journal of chronic diseases.