Sinikka Münte

Auricular acupuncture for dental anxiety: a randomized controlled trial.

Auricular acupuncture can be an effective treatment for acute anxiety, but there is a lack of direct comparisons of acupuncture to proven standard drug treatments. In this study we compared the efficacy of auricular acupuncture with intranasal midazolam, placebo acupuncture, and no treatment for reducing dental anxiety. Patients having dental extractions (n = 67) were randomized to (i) auricular acupuncture, (ii) placebo acupuncture, and (iii) intranasal midazolam and compared with a no treatment group. Anxiety was assessed before the interventions, at 30 min, and after the dental extraction. Physiological variables were assessed continuously. With the no treatment group as control, the auricular acupuncture group, and the midazolam group were significantly less anxious at 30 min as compared with patients in the placebo acupuncture group (Spielberger Stait-Trait Anxiety Inventory X1, P = 0.012 and <0.001, respectively). In addition, patient compliance assessed by the dentist was significantly improved if auricular acupuncture or application of intranasal midazolam had been performed (P = 0.032 and 0.049, respectively). In conclusion, both, auricular acupuncture and intranasal midazolam were similarly effective for the treatment of dental anxiety.

Increased Reading Speed for Stories Presented during General Anesthesia

BACKGROUND In the absence of explicit memories such as the recall and recognition of intraoperative events, memory of auditory information played during general anesthesia has been demonstrated with several tests of implicit memory. In contrast to explicit memory, which requires conscious recollection, implicit memory does not require recollection of previous experiences and is evidenced by a priming effect on task performance. The authors evaluated the effect of a standardized anesthetic technique on implicit memory, first using a word stem completion task, and then a reading speed task in a subsequent study. METHODS While undergoing lumbar disc surgery, 60 patients were exposed to auditory materials via headphones in two successive experiments. A balanced intravenous technique with propofol and alfentanil infusions and a nitrous oxide-oxygen mixture was used to maintain adequate anesthesia. In the first experiment, 30 patients were exposed randomly to one of the two lists of 34 repeated German nouns; in the second experiment, 30 patients were exposed to one of two tapes containing two short stories. Thirty control patients for each experiment heard the tapes without receiving anesthesia. All patients were tested for implicit memory 6-8 h later: A word stem completion task for the words and a reading speed task for the stories were used as measures of implicit memory. RESULTS The control group completed the word stems significantly more often with the words that they had heard previously, but no such effect was found in the anesthetized group. However, both the control and patient groups showed a decreased reading time of about 40 ms per word for the previously presented stories compared with the new stories. The patients had no explicit memory of intraoperative events. CONCLUSIONS Implicit memory was demonstrated after anesthesia by the reading speed task but not by the word stem completion task. Some methodologic aspects, such as using low frequency words or varying study and test modalities, may account for the negative results of the word stem completion task. Another explanation is that anesthesia with propofol, alfentanil, and nitrous oxide suppressed the word priming but not the reading speed measure of implicit memory. The reading speed paradigm seems to provide a stable and reliable measurement of implicit memory.

General anesthesia for interventional neuroradiology: propofol versus isoflurane

STUDY OBJECTIVE To compare recovery of psychomotor and cognitive ability after isoflurane and propofol-based general anesthesia. DESIGN Prospective, blinded interventional study. SETTING University hospital. PATIENTS 24 ASA physical status I and II patients undergoing embolization procedures for intracranial vascular lesions. INTERVENTIONS Isoflurane anesthesia or propofol anesthesia was given to patients. MEASUREMENTS Awakening time; early recovery (5 minutes, 15 minutes, 30 minutes) was assessed using orientation and Steward tests; medium recovery (30 minutes, 60 minutes, 120 minutes) was tested using Controlled World Association (COWAT) and Digit Span tests; late recovery (4 hours, 24 hours) was assessed using a Verbal Learning and Memory Test and three subtests of a computerized attention test battery. MAIN RESULTS Awakening time and early recovery of motor and respiratory function did not differ between groups. The propofol group scored worse in COWAT and Digit Span tests up to 60 minutes after anesthesia. Both groups showed an impairment of higher cognitive functions up to 24 hours after anesthesia. CONCLUSIONS Both isoflurane- and propofol-based anesthesia allow early extubation and recovery of basic psychomotor functions. More sophisticated tests show a decline of cognitive functions up to 24 hours after isoflurane- as well as propofol-based anesthesia. Because both anesthetics show similar recovery of psychomotor functions after long duration anesthesia, other factors such as subjective well-being and costs may be considered when deciding between these two anesthetics.

Cognitive dysfunction after abdominal surgery in elderly patients

Elderly patients often suffer from postoperative cognitive deficits (POCD) after serious surgical operations. The reasons for this are not well understood. We investigated the influence of the invasiveness of the operation and the duration of the operation as well as the patients preoperative physical status on measures of cognitive dysfunction. In a prospective study 59 elderly patients (mean age 69.2 years) were subjected to a neuropsychological test battery and a questionnaire following an abdominal surgical operation. The postoperative recovery with a focus on memory function was assessed using the Wechsler Memory Scale (WMS) seven days after the operation. Self-reported cognitive deficits were studied using the a questionnaire of experienced attention deficits (FEDA) three months after the operation. Postoperative psychological and self-reported test results varied as a function of the invasiveness and the duration of the operation. After more invasive operations patients reported a stronger deficit in activities of daily living and a reduction in drive than after less invasive operations. In addition, the duration of anesthesia influenced the experienced deficits. The self-reported deficits were more strongly influenced by the features of the operation than the psychological test data. The physical status of the patients according to the American Society of Anesthesiologists (ASA) along with the duration of anesthesia as covariate was identified as a good predictor for the cognitive recovery post operation.ZusammenfassungÄltere Patienten leiden häufig nach größeren chirurgischen Eingriffen an postoperativen kognitiven Dysfunktionen (POCD). Die Ursachen hierfür sind weitgehend unbekannt. Wir haben den Einfluss von Invasivität, Dauer der Operationen und Anästhesie sowie des körperlichen Allgemeinzustandes auf kognitive Dysfunktionen untersucht.Es wurden 59 ältere Patienten (mittleres Alter 69,2 Jahre) prospektiv anhand einer neuropsychologischen Testbatterie und eines Fragebogens nach einer abdominalchirurgischen Operation untersucht. Erfasst wurde die postoperative kognitive Erholung mit Fokus auf die Gedächtnisleistungen (Untertests der Wechsler Memory Scale, WMS) 7 Tage nach der Operation. Das subjektive Erleben kognitiver Beeinträchtigung im Alltag wurde mittels des Fragebogen erlebter Defizite der Aufmerksamkeit (FEDA) 3 Monate nach der Operation erhoben.Die postoperativ testpsychologisch nachgewiesenen und selbst erlebten kognitiven Funktionen bei älteren Patienten wurden signifikant von Invasivität und Dauer der Operation beeinflusst. Subjektiv bestand nach größeren Operationen eine erheblichere Beeinträchtigung der Verrichtung praktischer Tätigkeiten und des Antriebs im Alltag als nach kleineren operativen Eingriffen. Die Anästhesiedauer hatte tendenziell ebenfalls einen Einfluss auf das subjektive Erleben. Das subjektive Empfinden der Patienten (FEDA) war deutlich stärker vom Operationsverlauf abhängig als sich dies in den testpsychologisch erhobenen Parametern widerspiegelte. Der Gesundheitszustand der Patienten gemäß der American Society of Anesthesiologists (ASA) mit der Anästhesiedauer als Kovariante erwies sich als guter Prädiktor für die kognitive Erholung nach einer Operation.SummaryElderly patients often suffer from postoperative cognitive deficits (POCD) after serious surgical operations. The reasons for this are not well understood. We investigated the influence of the invasiveness of the operation and the duration of the operation as well as the patient’s preoperative physical status on measures of cognitive dysfunction.In a prospective study 59 elderly patients (mean age 69.2 years) were subjected to a neuropsychological test battery and a questionnaire following an abdominal surgical operation. The postoperative recovery with a focus on memory function was assessed using the Wechsler Memory Scale (WMS) seven days after the operation. Self-reported cognitive deficits were studied using the a questionnaire of experienced attention deficits (FEDA) three months after the operation.Postoperative psychological and self-reported test results varied as a function of the invasiveness and the duration of the operation. After more invasive operations patients reported a stronger deficit in activities of daily living and a reduction in drive than after less invasive operations. In addition, the duration of anesthesia influenced the experienced deficits. The self-reported deficits were more strongly influenced by the features of the operation than the psychological test data. The physical status of the patients according to the American Society of Anesthesiologists (ASA) along with the duration of anesthesia as covariate was identified as a good predictor for the cognitive recovery post operation.

Kognitive Dysfunktionen nach abdominal-chirurgischen Operationen bei älteren Patienten

Elderly patients often suffer from postoperative cognitive deficits (POCD) after serious surgical operations. The reasons for this are not well understood. We investigated the influence of the invasiveness of the operation and the duration of the operation as well as the patients preoperative physical status on measures of cognitive dysfunction. In a prospective study 59 elderly patients (mean age 69.2 years) were subjected to a neuropsychological test battery and a questionnaire following an abdominal surgical operation. The postoperative recovery with a focus on memory function was assessed using the Wechsler Memory Scale (WMS) seven days after the operation. Self-reported cognitive deficits were studied using the a questionnaire of experienced attention deficits (FEDA) three months after the operation. Postoperative psychological and self-reported test results varied as a function of the invasiveness and the duration of the operation. After more invasive operations patients reported a stronger deficit in activities of daily living and a reduction in drive than after less invasive operations. In addition, the duration of anesthesia influenced the experienced deficits. The self-reported deficits were more strongly influenced by the features of the operation than the psychological test data. The physical status of the patients according to the American Society of Anesthesiologists (ASA) along with the duration of anesthesia as covariate was identified as a good predictor for the cognitive recovery post operation.ZusammenfassungÄltere Patienten leiden häufig nach größeren chirurgischen Eingriffen an postoperativen kognitiven Dysfunktionen (POCD). Die Ursachen hierfür sind weitgehend unbekannt. Wir haben den Einfluss von Invasivität, Dauer der Operationen und Anästhesie sowie des körperlichen Allgemeinzustandes auf kognitive Dysfunktionen untersucht.Es wurden 59 ältere Patienten (mittleres Alter 69,2 Jahre) prospektiv anhand einer neuropsychologischen Testbatterie und eines Fragebogens nach einer abdominalchirurgischen Operation untersucht. Erfasst wurde die postoperative kognitive Erholung mit Fokus auf die Gedächtnisleistungen (Untertests der Wechsler Memory Scale, WMS) 7 Tage nach der Operation. Das subjektive Erleben kognitiver Beeinträchtigung im Alltag wurde mittels des Fragebogen erlebter Defizite der Aufmerksamkeit (FEDA) 3 Monate nach der Operation erhoben.Die postoperativ testpsychologisch nachgewiesenen und selbst erlebten kognitiven Funktionen bei älteren Patienten wurden signifikant von Invasivität und Dauer der Operation beeinflusst. Subjektiv bestand nach größeren Operationen eine erheblichere Beeinträchtigung der Verrichtung praktischer Tätigkeiten und des Antriebs im Alltag als nach kleineren operativen Eingriffen. Die Anästhesiedauer hatte tendenziell ebenfalls einen Einfluss auf das subjektive Erleben. Das subjektive Empfinden der Patienten (FEDA) war deutlich stärker vom Operationsverlauf abhängig als sich dies in den testpsychologisch erhobenen Parametern widerspiegelte. Der Gesundheitszustand der Patienten gemäß der American Society of Anesthesiologists (ASA) mit der Anästhesiedauer als Kovariante erwies sich als guter Prädiktor für die kognitive Erholung nach einer Operation.SummaryElderly patients often suffer from postoperative cognitive deficits (POCD) after serious surgical operations. The reasons for this are not well understood. We investigated the influence of the invasiveness of the operation and the duration of the operation as well as the patient’s preoperative physical status on measures of cognitive dysfunction.In a prospective study 59 elderly patients (mean age 69.2 years) were subjected to a neuropsychological test battery and a questionnaire following an abdominal surgical operation. The postoperative recovery with a focus on memory function was assessed using the Wechsler Memory Scale (WMS) seven days after the operation. Self-reported cognitive deficits were studied using the a questionnaire of experienced attention deficits (FEDA) three months after the operation.Postoperative psychological and self-reported test results varied as a function of the invasiveness and the duration of the operation. After more invasive operations patients reported a stronger deficit in activities of daily living and a reduction in drive than after less invasive operations. In addition, the duration of anesthesia influenced the experienced deficits. The self-reported deficits were more strongly influenced by the features of the operation than the psychological test data. The physical status of the patients according to the American Society of Anesthesiologists (ASA) along with the duration of anesthesia as covariate was identified as a good predictor for the cognitive recovery post operation.

Spectral entropy as a measure of hypnosis and hypnotic drug effect of total intravenous anesthesia in children during slow induction and maintenance.

Background: We evaluated whether spectral entropy (SpE) can measure the depth of hypnosis and the hypnotic drug effect in children during total intravenous anesthesia. Methods: Sixty healthy children, aged 3–16 yr, were studied. Anesthesia was induced with an increasing target controlled infusion of propofol, and maintained by a stable remifentanil infusion and variable concentrations of target controlled infusion propofol. Depth of hypnosis was assessed according to the University of Michigan Sedation Scale (UMSS). Estimated plasma (Cp) and pseudo effect site (Ceff) propofol concentrations reflected the hypnotic drug effect. Patients were stratified to three age groups. The correlations between SpE versus UMSS, Cp, and Ceff were analyzed by Prediction Probability (Pk). The pharmacodynamic relationship between SpE and Cp, and the differences of SpE values between the age groups at the corresponding UMSS levels, were studied. Results: Respective mean Pk values for the youngest, middle, and oldest age groups were: 1) during induction: SpE versus UMSS 0.87, 0.87, and 0.93; SpE versus Cp 0.92, 0.95, and 0.97; and SpE versus Ceff 0.88, 0.94, and 0.95; 2) during maintenance: SpE versus Ceff 0.86, 0.75, and 0.81. The pharmacodynamic analysis determined an association between SpE and Cp that followed the Emax model closely. There were significant differences in SpE values between age groups at corresponding UMSS sedation levels. Conclusions: SpE measures the level of hypnosis and hypnotic drug effect in children during total intravenous anesthesia. There is an age dependency associated with SpE. Anesthesia should not be steered solely on the basis of SpE.

Postoperative reading speed does not indicate implicit memory in elderly cardiac patients after propofol and remifentanyl anaesthesia

Background: A recent study in young patients undergoing propofol‐alfentanil‐nitrous oxide anaesthesia demonstrated implicit memory for stories presented during operation using a postoperative reading speed task. In this study we investigated whether patients who tolerate only small amounts of anaesthetics are prone to develop implicit and explicit memories about intraoperative events.

The Narcotrend index indicates age-related changes during propofol induction in children.

BACKROUND: The Narcotrend® electr oencephalogram monitor is designed to measure hypnotic state during anesthesia. We performed this study to evaluate the effectiveness and reliability of the Narcotrend monitor in assessing hypnotic state and loss of consciousness (LOC) during propofol anesthesia induction in children. METHODS: Sixty-two children, aged 1–5 (n = 17), 6–12 (n = 23), and 13–16 (n = 21) yr, scheduled for elective surgery were studied. The patients were premedicated with oral midazolam 0.5 mg/kg. After IV access, propofol target controlled infusion (TCI) was started with 0.5 &mgr;g/mL and increased by 0.5 &mgr;g/mL increments every 2 min until the child did not respond to any verbal command or physical stimuli. A manual scheme was used for children weighing <15 kg. Hypnotic state was measured every minute from the start of the propofol infusion using the University of Michigan Sedation Scale (UMSS). LOC was defined as a transition of UMSS scale value 2 to 3. The Narcotrend index (NI) was recorded before the start of induction and during the whole study period. NI values were noted simultaneously, yet independently of the sedation measurements. Prediction probability (PK) was used to assess the correspondence between NI and UMSS. Sensitivity and specificity of NI for differentiating between consciousness and unconsciousness were calculated. NI values at specific UMSS levels were compared between the different age groups and the relationships between TCI propofol concentrations and sedation levels were assessed using correlation analysis. RESULTS: A PK-value of 0.84 (95% CI [0.80–0.88]) of NI was calculated from the data for the detection of LOC. Similarly, a PK value of 0.82 (95% CI [0.78–0.86]) indicated agreement between NI and UMSS values. The average NI values differed between successive UMSS sedation levels 0 and 1 and levels 1 and 2 (P < 0.01). In the youngest age group, the NI discriminated between UMSS levels 2 and 3, in the second age group between levels 1 and 2 and 2 and 3, and in the oldest age group between 0 and 1. Furthermore, the NI values differed significantly between age groups at UMSS levels 1–4 (P < 0.005), with the NI values being higher in younger compared with older children. The average NI value at LOC was 68. For the detection of consciousness, a sensitivity of 0.67 and specificity of 0.79 were achieved. Spearman correlation coefficients indicated higher association between TCI propofol concentrations and UMSS (0.96) than between NI and UMSS (−0.68). CONCLUSIONS: During propofol induction in children, the Narcotrend electroencephalogram monitor was capable of following changes in the sedation level of children to some extent, but also had a relatively high probability (0.18) of incorrectly predicting changes in conscious state. Therefore, the monitor should not solely be used to guide sedation and anesthesia. NI was age-dependent and younger children had higher NI-values than older children at the same level of sedation.

Implicit memory for words played during isoflurane- or propofol-based anesthesia: The lexical decision task

Background Unconscious processing of words during general anesthesia has been suggested after surgery with several tests of implicit memory. Patients can neither recall those words nor do they have explicit memories of other intraoperative events. It is unclear to what degree information is processed during general anesthesia and which tests are best suited to detect implicit memory. In the current study, a lexical decision paradigm not previously used to demonstrate implicit memory during anesthesia was used. Methods Sixty patients undergoing lumbar disc surgery were assigned to receive isoflurane infusion– or propofol infusion–based anesthesia combined with alfentanil infusions and a nitrous oxide–oxygen mixture. A control group of 10 medical students listened to tapes without receiving anesthesia. Two tapes, each containing a list of 30 low-frequency German nouns repeated for 15 min, were prepared, with half of the patients listening to tape A and the other half listening to tape B during the operation. Exposure time was 15 min from the time of skin incision onward. In the test phase, approximately 7 h later, words from lists A and B plus 60 nonwords were presented in random order by a computer program. Subjects were asked to indicate, by pressing one of two response buttons, whether the spoken word was or was not a legal German word (lexical decision). Results A recognition test revealed chance recognition for words presented during anesthesia. Lexical decision responses, however, were slightly faster to primed (previously presented) words than to unprimed (not previously presented) words when the entire group of patients was tested, suggesting a small implicit memory effect, which barely failed to reach the significance level. When the two medication groups were tested separately, no significant implicit memory effect could be ascertained statistically. The effects of previous exposure were much more pronounced in the control group. Conclusions Balanced anesthesia techniques with isoflurane or propofol lead to only a minimal, statistically borderline implicit memory effect in the lexical decision paradigm.

No Implicit Memory for Stories Played during Isoflurane/alfentanil/nitrous Oxide Anesthesia: A Reading Speed Measurement

Implicit memory of intraoperatively presented stories was recently detected by using the reading speed paradigm during propofol-alfentanil-nitrous oxide anesthesia. Our main goal was to evaluate the reading speed test procedure under another anesthetic regimen, i.e., isoflurane combined with nitrous oxide and alfentanil-infusion. In both experiments, patients were premedicated with oral midazolam. In a previous experiment, patients postoperatively read “old” stories that had been presented during anesthesia quicker compared with “new,” unpresented stories. The same study design and test material as in the previous experiment were used. One of two audio tapes with two short stories was played randomly to patients during lumbar disk surgery and to awake controls. Approximately 7 h later, a structured interview and the reading speed test were used to determine whether the participants had any explicit or implicit memories of the presented stories. The results of 30 patients and 30 controls were calculated. Whereas the control participants showed an intact explicit and implicit memory of the previously presented material, no such effect was found in the anesthetized patients. The present experiment shows that changing the main anesthetic in otherwise equal study conditions, i.e., propofol to isoflurane (end-expiratory 0.7%), implicit memory is abolished in anesthetized patients. Implications: We showed that implicit memory during general anesthesia can be abolished by changing the hypnotic anesthetic. Increased postoperative reading speed for stories presented during propofol-alfentanil-nitrous oxide anesthesia was shown in a previous experiment, but not in our study using isoflurane for balanced anesthesia.