Monitoring depth of anaesthesia.

In clinical practice, indirect and non-specific signs are used for monitoring anaesthetic adequacy. These include haemodynamic, respiratory, muscular and autonomic signs. These measures do not indicate adequacy of anaesthesia in a reliable manner. Many attempts have been made to find a more accurate monitor. Direct monitoring of anaesthetic effect should be possible by EEG measurement. EEG information can be reduced, condensed and simplified, leading to single numbers (spectral edge frequency and median frequency). These methods appear insufficient for assessing anaesthetic adequacy. The bispectral index, derived from bispectral analysis of the EEG, is a very promising tool for measuring adequacy of anaesthesia. An alternative approach is to monitor evoked potentials. Middle latency auditory evoked potentials may be helpful in assessing anaesthetic adequacy. Both techniques need further validation.

[1]  D. Chassard,et al.  Auditory evoked potentials during propofol anaesthesia in man. , 1989, British journal of anaesthesia.

[2]  D R Stanski,et al.  Population pharmacokinetics and pharmacodynamics of thiopental: the effect of age revisited. , 1990, Anesthesiology.

[3]  T W Picton,et al.  Human auditory evoked potentials. II. Effects of attention. , 1974, Electroencephalography and clinical neurophysiology.

[4]  J. Antognini,et al.  Does the brain influence somatic responses to noxious stimuli during isoflurane anesthesia , 1994 .

[5]  Michael Daunderer,et al.  Anesthesia with Increasing Doses of Sufentanil and Midlatency Auditory Evoked Potentials in Humans , 1995, Anesthesia and analgesia.

[6]  C P Heneghan,et al.  Effect of etomidate on the auditory evoked response in man. , 1985, British journal of anaesthesia.

[7]  Robert I. Block,et al.  Learning and Consciousness during General Anesthesia , 1992, Anesthesiology.

[8]  G. Plourde.  The Effects of Propofol on the 40-Hz Auditory Steady-State Response and on the Electroencephalogram in Humans , 1996, Anesthesia and analgesia.

[9]  M. Pinsker.  Anesthesia: a pragmatic construct. , 1986, Anesthesia and Analgesia.

[10]  J. Drummond,et al.  A comparison of median frequency, spectral edge frequency, a frequency band power ratio, total power, and dominance shift in the determination of depth of anesthesia , 1991, Acta anaesthesiologica Scandinavica.

[11]  A. Aitkenhead,et al.  Therapeutic suggestions during general anaesthesia in patients undergoing hysterectomy. , 1992, British journal of anaesthesia.

[12]  S L Shafer,et al.  Thiopental pharmacodynamics. I. Defining the pseudo-steady-state serum concentration-EEG effect relationship. , 1992, Anesthesiology.

[13]  I. Russell.  Balanced anesthesia: does it anesthetize? , 1985, Anesthesia and analgesia.

[14]  H. Schwilden,et al.  Quantitation of the EEG and pharmacodynamic modelling of hypnotic drugs: etomidate as an example. , 1985, European journal of anaesthesiology.

[15]  James C. Scott,et al.  Electroencephalographic quantitation of opioid effect: comparative pharmacodynamics of fentanyl and sufentanil. , 1991, Anesthesiology.

[16]  E Pöppel,et al.  Midlatency Auditory Evoked Potentials and Explicit and Implicit Memory in Patients Undergoing Cardiac Surgery , 1994, Anesthesiology.

[17]  D. Suresh.  Nightmares and recovery from anesthesia. , 1991, Anesthesia and analgesia.

[18]  K. Millar,et al.  Efficacy of therapeutic suggestions presented during anaesthesia: re-analysis of conflicting results. , 1993, British journal of anaesthesia.

[19]  C. Doré,et al.  Early cortical auditory evoked response in anaesthesia: comparison of the effects of nitrous oxide and isoflurane. , 1989, British journal of anaesthesia.

[20]  J. Brimacombe.  Peri‐operative nightmares in surgical patients , 1993, Anaesthesia.

[21]  H Schwilden,et al.  Effective therapeutic infusions produced by closed-loop feedback control of methohexital administration during total intravenous anesthesia with fentanyl. , 1990, Anesthesiology.

[22]  H Schwilden,et al.  Closed‐loop Feedback Control of Methohexital Anesthesia by Quantitative EEG Analysis in Humans , 1987, Anesthesiology.

[23]  S. Hillyard,et al.  Human auditory evoked potentials. I. Evaluation of components. , 1974, Electroencephalography and clinical neurophysiology.

[24]  D R Stanski,et al.  A Model for Studying Depth of Anesthesia and Acute Tolerance to Thiopental , 1983, Anesthesiology.

[25]  D. Sessler,et al.  Lower esophageal contractility predicts movement during skin incision in patients anesthetized with halothane, but not with nitrous oxide and alfentanil. , 1989, Anesthesiology.

[26]  C. Frith,et al.  LEVELS OF CONSCIOUSNESS IN VOLUNTEERS BREATHING SUB-MAC CONCENTRATIONS OF ISOFLURANE , 1990 .

[27]  T W Picton,et al.  Human Auditory Steady‐State Response During General Anesthesia , 1990, Anesthesia and analgesia.

[28]  Pask Ea,et al.  HOMOSEXUALITY AS A CRIME. , 1965 .

[29]  P. Richardson,et al.  IMPROVED RECOVERY AND REDUCED POSTOPERATIVE STAY AFTER THERAPEUTIC SUGGESTIONS DURING GENERAL ANAESTHESIA , 1988, The Lancet.

[30]  P. Sebel,et al.  Evoked potentials following diazepam or fentanyl , 1987, Anaesthesia.

[31]  W. L. Davies,et al.  LOWER OESOPHAGEAL CONTRACTILITY: A NEW MONITOR OF ANAESTHESIA , 1984, The Lancet.

[32]  L. Jacoby,et al.  Memory influences subjective experience: Noise judgments. , 1988 .

[33]  D R Stanski,et al.  Plasma Concentrations of Alfentanil Required to Supplement Nitrous Oxide Anesthesia for General Surgery , 1986, Anesthesiology.

[34]  E. Eger,et al.  The Electroencephalogram in Man Anesthetized with Forane , 1971, Anesthesiology.

[35]  J. Jones,et al.  Hearing and memory in anaesthetised patients. , 1986, British medical journal.

[36]  Paul F. White,et al.  Electroencephalogram bispectral analysis predicts the depth of midazolam-induced sedation. , 1996 .

[37]  J. Antognini,et al.  Exaggerated Anesthetic Requirements in the Preferentially Anesthetized Brain , 1993, Anesthesiology.

[38]  I. Russell.  Midazolam-alfentanil: an anaesthetic? An investigation using the isolated forearm technique. , 1993, British journal of anaesthesia.

[39]  R. Sandin,et al.  Awareness during total i.v. anaesthesia. , 1993, British journal of anaesthesia.

[40]  B. Hitt,et al.  PHARMACOKINETICS OF INTRATHECAL LIDOCAINE IN THE MONKEY , 1980 .

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

[42]  C P Heneghan,et al.  Effect of surgical stimulation on the auditory evoked response. , 1988, British journal of anaesthesia.

[43]  Philip D. Woodbridge,et al.  CHANGING CONCEPTS CONCERNING DEPTH OF ANESTHESIAE , 1957 .

[44]  Y. Umegaki.  [Auditory steady-state response to sinusoidally amplitude-modulated tones. Second report: investigation of response in the sleeping state]. , 1995, Nihon Jibiinkoka Gakkai kaiho.

[45]  A. Aitkenhead,et al.  Relationship between lower oesophageal contractility and type of surgical stimulation. , 1990, British journal of anaesthesia.

[46]  D. Fowles,et al.  No evidence of classical conditioning of electrodermal responses during anesthesia. , 1992, Anesthesiology.

[47]  Gilles Plourde,et al.  Comparison of the Effects of Enflurane/N2 O on the 40-Hz Auditory Steady-State Response Versus the Auditory Middle-Latency Response1 , 1996, Anesthesia and analgesia.

[48]  I. Rampil,et al.  Prognostic Value of Computerized EEG Analysis during Carotid Endarterectomy , 1983, Anesthesia and analgesia.

[49]  H. Shapiro,et al.  Automated EEG processing for intraoperative monitoring: a comparison of techniques. , 1980, Anesthesiology.

[50]  D R Stanski,et al.  EEG quantitation of narcotic effect: the comparative pharmacodynamics of fentanyl and alfentanil. , 1985, Anesthesiology.

[51]  T. Lee,et al.  EFFECTS OF CLONIDINE ON NOREP INEPHRINE OR KC1 PRECONTRACTED PULMONARY ARTERIES , 1992 .

[52]  Claude Meistelman,et al.  Bayesian forecasting during muscle relaxant computer-controlled infusion: 35 , 1997 .

[53]  I. F. Russell,et al.  COMPARISON OF WAKEFULNESS WITH TWO ANAESTHETIC REGIMENS , 1986 .

[54]  E Pöppel,et al.  Effects of increasing doses of alfentanil, fentanyl and morphine on mid-latency auditory evoked potentials. , 1993, British journal of anaesthesia.

[55]  J L Neigh,et al.  The Electroencephalographic Pattern during Anesthesia with Ethrane: Effects of Depth of Anesthesia Paco2, and Nitrous Oxide , 1971, Anesthesiology.

[56]  C Prys-Roberts,et al.  Anaesthesia: a practical or impractical construct? , 1987, British Journal of Anaesthesia.

[57]  I G Vlachonikolis,et al.  Relationship between lower oesophageal contractility, clinical signs and halothane concentration during general anaesthesia and surgery in man. , 1987, British journal of anaesthesia.

[58]  D R Stanski,et al.  The Effect of Increasing Age on Thiopental Disposition and Anesthetic Requirement , 1985, Anesthesiology.

[59]  H Schwilden,et al.  Closed-loop feedback controlled administration of alfentanil during alfentanil-nitrous oxide anaesthesia. , 1993, British journal of anaesthesia.

[60]  R. R. Schultetus,et al.  Wakefulness during Cesarean Section after Anesthetic Induction with Ketamine, Thiopental, or Ketamine and Thiopental Combined , 1986, Anesthesia and analgesia.

[61]  P. White,et al.  Relationship Between Hemodynamic and Electroencephalographic Changes During General Anesthesia , 1989, Anesthesia and Analgesia.

[62]  Auditory evoked potentials during isoflurane anaesthesia , 1986, Acta anaesthesiologica Scandinavica.

[63]  I. Kissin,et al.  General anesthetic action: an obsolete notion? , 1993, Anesthesia and Analgesia.

[64]  H. Schwilden,et al.  Closed-loop feedback control of propofol anaesthesia by quantitative EEG analysis in humans. , 1989, British journal of anaesthesia.

[65]  C P Heneghan,et al.  Selective effect of althesin on the auditory evoked response in man. , 1986, British journal of anaesthesia.

[66]  J. Hilgenberg.  Intraoperative awareness during high-dose fentanyl--oxygen anesthesia. , 1981, Anesthesiology.

[67]  Ernst Pöppel,et al.  Mid-latency auditory evoked potentials and circulatory response to loud sounds , 1994 .

[68]  M. C. Rogers,et al.  Hemodynamic Responses in Brain Dead Organ Donor Patients , 1985, Anesthesia and analgesia.

[69]  R. Dirksen,et al.  A System Model for Halothane Closed-Circuit Anesthesia: Structure Considerations and Performance Evaluation , 1995, Anesthesiology.

[70]  K. Bowers,et al.  Unconscious Cognition in the Context of General Anesthesia , 1994, Consciousness and Cognition.

[71]  C. Prys‐roberts,et al.  Oesophageal contractility during total i.v. anaesthesia with and without glycopyrronium. , 1991, British journal of anaesthesia.

[72]  R. Dutton,et al.  Subanesthetic Concentrations of Desflurane and Propofol Suppress Recall of Emotionally Charged Information , 1995, Anesthesia and analgesia.

[73]  E Pöppel,et al.  Mid-latency auditory evoked potentials during ketamine anaesthesia in humans. , 1993, British journal of anaesthesia.

[74]  E. Eger,et al.  A Comparative Study of Halothane and Halopropane Anesthesia: Including Method for Determining Equipotency , 1963, Anesthesiology.

[75]  S. Cotev,et al.  Estimating anesthetic depth by electroencephalography during anesthetic induction and intubation in patients undergoing cardiac surgery. , 1990, Journal of clinical anesthesia.

[76]  M F Roizen,et al.  Anesthetic Doses Blocking Adrenergic (Stress) and Cardiovascular Responses to Incision—MAC BAR , 1981, Anesthesiology.

[77]  C P Heneghan,et al.  Effects of halothane or enflurane with controlled ventilation on auditory evoked potentials. , 1984, British journal of anaesthesia.

[78]  Aitkenhead,et al.  Awareness during anaesthesia: a review. , 1983, Annals of the Royal College of Surgeons of England.

[79]  T Seppälä,et al.  Increases in Hemodynamic Variables and Catecholamine Levels after Rapid Increase in Isoflurane Concentration , 1993, Anesthesiology.

[80]  E. Eger,et al.  Rapid Increase in Desflurane Concentration Is Associated with Greater Transient Cardiovascular Stimulation Than with Rapid Increase in Isoflurane Concentration in Humans , 1994, Anesthesiology.

[81]  J. Mainzer.  Awareness, muscle relaxants and balanced anaesthesia , 1979, Canadian Anaesthetists' Society journal.

[82]  I J Rampil,et al.  Anesthetic Potency Is Not Altered after Hypothermic Spinal Cord Transection in Rats , 1994, Anesthesiology.

[83]  R. Bedford,et al.  A Comparison of EEG Determinants of Near‐Awakening from Isoflurane and Fentanyl Anesthesia: Spectral Edge, Median Power Frequency, and δ Ratio , 1989, Anesthesia and analgesia.

[84]  G. Plourde,et al.  The auditory steady state response during sufentanil anaesthesia. , 1991, British journal of anaesthesia.

[85]  P. White,et al.  Nail polish and oximetry. , 1989, Anesthesia and analgesia.

[86]  F. Gibbs,et al.  EFFECT ON THE ELECTRO-ENCEPHALOGRAM OF CERTAIN DRUGS WHICH INFLUENCE NERVOUS ACTIVITY , 1937 .

[87]  T. Gasser,et al.  Statistical methods for investigating phase relations in stationary stochastic processes , 1971 .

[88]  C. Hug,et al.  Does opioid "anesthesia" exist? , 1990, Anesthesiology.

[89]  B. Bonke,et al.  Awareness and Recall during General Anesthesia: Facts and Feelings , 1993, Anesthesiology.

[90]  D. Schwender,et al.  A case of intra‐operative awareness during balanced anaesthesia with sufentanil , 1996, Anaesthesia.

[91]  P. Sebel,et al.  Prediction of Movement Using Bispectral Electroencephalographic Analysis During Propofol/Alfentanil or Isoflurane/Alfentanil Anesthesia , 1995, Anesthesia and analgesia.

[92]  I J Rampil,et al.  Anesthetic Potency (MAC) Is Independent of Forebrain Structures in the Rat , 1993, Anesthesiology.

[93]  M. Larson.  Surgically induced hypertension in brain dead patients. , 1985, Anesthesia and analgesia.