Narcotrend Monitor Research Articles

Study on correlation between depth of sedation and Narcotrend index in Midazolam target-controlled infusion

Objective To investigate the reliability of Narcotrend for monitoring the depth of sedation [the observer's assessment of alterness/sedation(OAA/S) scale] with midazolam and correlation between the depth of sedation and Narcotrend index.Methods 0 ASA Ⅰ-Ⅱ status patients scheduled for elective lower limb operations underwent spinal anesthesia,who were given target-controlled infusion of midazolam.Target plasma concentration was 50ng/ ml at first and increased by 10 ng/ml each grade until OAA/S scale became 1 point.Each target concentration infusion was maintained for 5min.Observe the patient the OAA/S scale to be 5 points.If the operation was not over yet,regulated the appropriate depth of sedation until the end of operation.The Narcotrend index of different OAA/S scale and heart rate,mean arterial pressure,respiration were recorded.Results In the deepening or recovery phase of sedation,OAA/S scales were correlated with Narcotrend index (Spearman' s r =0.786,0.652,all P ＜ 0.05).Conclusion Narcotrend is a good index to guide target controlled infusion of midazolam,the index is closely related with the depth of sedation of midazolam. Key words: Midazolam; Target controlled infusion ; Depth of sedation; Narcotrend monitor

Application of Narcotrend® Monitor for Evaluation of Depth of Anesthesia in Infants Undergoing Cardiac Surgery: a Prospective Control Study

Background and objectivesTo investigate the clinic effectiveness, safety and feasibility of Narcotrend® monitor for evaluation of depth of anesthesia in congenital heart disease (CHD) infants undergoing cardiac surgery. MethodsA total of 80 infants receiving general anesthesia in selective surgery were randomly selected. Infants were assigned into two groups (n = 40 per group). In the Narcotrend group, the depth of anesthesia was monitored with the Narcotrend monitor. In the standard group, the depth of anesthesia was controlled according to the experience. The mean arterial pressure (MAP) and heart rate (HR) were determined, as well as the dose of fentanyl, muscle relaxant, recovery time and extubation time were recorded. ResultsIn both groups, vital signs were stable during the surgery. When compared with the standard group, the MAP and HR were more stable, the total dose of fentanyl and muscle relaxant were significantly reduced and the recovery time and extubation time were markedly shortened in the Narcotrend group. ConclusionThe application of Narcotrend monitor was beneficial to the control of the depth of anesthesia in CHD infants receiving total intravenous anesthesia, in which small amount of narcotics can achieve optimal anesthesia. Moreover, the recovery time and extubation time are reduced and the harmful consequence such as intraoperative awareness can be avoided.

Application of Narcotrend® Monitor for Evaluation of Depth of Anesthesia in Infants Undergoing Cardiac Surgery: a Prospective Control Study

Background and objectivesTo investigate the clinic effectiveness, safety and feasibility of Narcotrend® monitor for evaluation of depth of anesthesia in congenital heart disease (CHD) infants undergoing cardiac surgery. MethodsA total of 80 infants receiving general anesthesia in selective surgery were randomly selected. Infants were assigned into two groups (n=40 per group). In the Narcotrend group, the depth of anesthesia was monitored with the Narcotrend monitor. In the standard group, the depth of anesthesia was controlled according to the experience. The mean arterial pressure (MAP) and heart rate (HR) were determined, as well as the dose of fentanyl, muscle relaxant, recovery time and extubation time were recorded. ResultsIn both groups, vital signs were stable during the surgery. When compared with the standard group, the MAP and HR were more stable, the total dose of fentanyl and muscle relaxant were significantly reduced and the recovery time and extubation time were markedly shortened in the Narcotrend group. ConclusionThe application of Narcotrend monitor was beneficial to the control of the depth of anesthesia in CHD infants receiving total intravenous anesthesia, in which small amount of narcotics can achieve optimal anesthesia. Moreover, the recovery time and extubation time are reduced and the harmful consequence such as intraoperative awareness can be avoided.

Effects of electromyographic activity on the accuracy of Narcotrend and bispectral index during sedation with dexmedetomidine

Objective To investigate the effects of electromyographic activity on the accuracy of Narcotrend and bispectral index (BIS) during sedation with dexmedetomidine (Dex) under epidural anesthesia.Methods Sixteen patients scheduled for epidural anesthesia,9 males and 7 females,ASA Ⅰ or Ⅱ,aged 18 y-60 y,weighing 51 kg-93 kg,BMI 19.2 kg/m2-27.8 kg/m2 were prospectively studied.After the induction of epidural anesthesia,a loading dose of Dex was administered at 0.5 μg/kg per 15 min,followed by a continuous infusion at 0.4 μg ·kg-1 ·h-1,BIS and Narcotrend were monitored simultaneously,both values and EMG which was indicated on the BIS platform were recorded every minute.Sedation was assessed using the Observer's Assessment of Alterness/Sedation Scale (OAA/S) as well.The correlation between Narcotrend index (NTI)/BIS and EMG was analyzed.Results As the EMG activities above 50 dB elevated,BIS and NTI values were not increased (r=0.113,P=0.249;r=0.160,P=0.249).The misleading high BIS/NTI ≥85 occurred among 8 (50％ of all cases) and 9 (56％ of all cases) patients,respectively,at OAA/S ≤3.While there was no correlation (r=-0.046,P=-0.855) between BIS M (QR)87 (86-91) and EMG 34 (32-36),and there was no correlation (r=0.090,P=0.732) between NTI 90 (87-94) and EMG 41 (37-48),either.Conclusions During sedation with Dex under epidural anesthesia,high EMG activities do not result in BIS/NTI value increases.Impractical high BIS/NTI values are not caused by EMG elevation.Under sedation with Dex,the Narcotrend and BIS monitor are comparatively reliable with regard to their insusceptibility to increased EMG activity. Key words: Electromyographic activity; Consciousness monitors; Dexmedetomidine; Conscious sedation

A randomized controlled trial of preprocedure administration of parecoxib for therapeutic endoscopic retrograde cholangiopancreatography

IntroductionParecoxib is occasionally used for analgesia in postprocedural patients. The clinical efficacy of parecoxib used for endoscopic retrograde cholangiopancreatography (ERCP) is controversial. The aim of the study was to determine the clinical efficacy of preprocedure administration of parecoxib for therapeutic ERCP patients.MethodsEighty-five patients who underwent therapeutic ERCP in a single year were randomly assigned to normal saline group (C, n = 43) and parecoxib group (P, n = 42). Patients in group C received normal saline and those in group P received 40 mg of parecoxib intravenously in equivalent volume. Patients in both groups received the saline or parecoxib 60 seconds before administration of the sedative agents. All patients were monitored for the depth of sedation by using the NarcotrendTM monitor, maintaining stage D0–E0 during ERCP. All patients were oxygenated with 100% O2 via nasal cannula and sedated with 0.03 mg/kg of intravenous midazolam and 1 μg/kg of intravenous fentanyl as well as the titration of intravenous propofol. After the ERCP procedure, pethidine in an intramuscular dose of 0.5–1.0 mg/kg was used as rescue medication. The pain scores (visual analog scale [VAS], 0–10) at 2, 12, and 24 hours post-ERCP, the total number of doses of pethidine used, the dose volume of pethidine used, patient satisfaction, endoscopist satisfaction, and complications were recorded.ResultsThere were no significant differences in sedative and analgesic agents used during the procedure, pain at 24 hours post-ERCP, endoscopist satisfaction, and complications in both groups. The total number of doses of pethidine used post-ERCP in group C was significantly higher than in group P. Additionally, the mean pain score at 2 and 12 hours post-ERCP in group C was significantly greater than in group P. Patient satisfaction in group P was higher than in group C.ConclusionPreprocedure administration of parecoxib for therapeutic ERCP patients was clinically effective. The analgesic efficacy of a standard dose of parecoxib was clearly demonstrated during the first 12 hours postprocedure. Additionally, patient satisfaction in the parecoxib group was also higher than in the control group.

Deep sedation for endoscopic retrograde cholangiopancreatography: a comparison between clinical assessment and Narcotrend(TM) monitoring.

IntroductionModerate to deep sedation is generally used for endoscopic retrograde cholangiopancreatography (ERCP). The depth of sedation is usually judged by clinical assessment and electroencephalography-guided monitoring. The aim of this study was to compare the clinical efficacy of clinical assessment and NarcotrendTM monitoring during deep-sedated ERCP.MethodsOne hundred patients who underwent ERCP in a single year were randomly assigned to either group C or group N. Patients in group C (52) were sedated using the Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scale. Patients in group N (48) were sedated using the NarcotrendTM system. The MOAA/S scale 1 or 2 and the NarcotrendTM index 47–56 to 57–64 were maintained during the procedure. The primary outcome variable of the study was the successful completion of the endoscopic procedure. The secondary outcome variables were the total dose of propofol used during the procedure, complications during and immediately after procedure, and recovery time.ResultsAll endoscopies were completed successfully. The mean total dose of propofol in group C was significantly lower than that in group N. However, the mean dose of propofol, expressed as dose/kg or dose/kg/h in both groups, was not significantly different (P = 0.497, 0.136). Recovery time, patient tolerance and satisfaction, and endoscopist satisfaction were comparable between the two groups. All sedation-related adverse events during and immediately after the procedure, such as hypotension, hypertension, tachycardia, bradycardia, transient hypoxia, and upper airway obstruction, in group C (62.2%) were significantly higher than in group N (37.5%) (P = 0.028).ConclusionClinical assessment and NarcotrendTM-guided sedation using propofol for deep sedation demonstrated comparable propofol dose and recovery time. Both monitoring systems were equally safe and effective. However, the NarcotrendTM-guided sedation showed lower hemodynamic changes and fewer complications compared with the clinical assessment-guided sedation.

Deep sedation for endoscopic retrograde cholangiopacreatography

Sedation and analgesia comprise an important element of unpleasant and often prolonged endoscopic retrograde cholangiopacreatography (ERCP), contributing, however, to better patient tolerance and compliance and to the reduction of injuries during the procedure due to inappropriate co-operation. Although most of the studies used a moderate level of sedation, the literature has revealed the superiority of deep sedation and general anesthesia in performing ERCP. The anesthesiologist's presence is mandatory in these cases. A moderate sedation level for ERCP seems to be adequate for octogenarians. The sedative agent of choice for sedation in ERCP seems to be propofol due to its fast distribution and fast elimination time without a cumulative effect after infusion, resulting in shorter recovery time. Its therapeutic spectrum, however, is much narrower and therefore careful monitoring is much more demanding in order to differentiate between moderate, deep sedation and general anesthesia. Apart from conventional monitoring, capnography and Bispectral index or Narcotrend monitoring of the level of sedation seem to be useful in titrating sedatives in ERCP.

Advances in clinical application of the Narcotrend monitor

As more attention is paid to the importance of maintenance of proper anesthetic depth and to the perniciousness of intra-operative awareness, the new type electroencephalographic monitor, Narcotrend, is more and more extensively applied in clinic and research fields. Its efficacy has been confirmed by a large amount of studies. This review will focus on main advances in clinical application of the narcotrend monitor: evaluation on anesthetic depth; exploration on new field and research prospect. Key words: Narcotrend ; Narcotrend index ; Anesthetic depth ; Electroencephalogram ; Monitoring ;

The Narcotrend Index Indicates Age-Related Changes During Propofol Induction in Children

The Narcotrend electroencephalogram 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. 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 microg/mL and increased by 0.5 microg/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. 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). 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.

Narcotrend-assisted propofol/remifentanil anaesthesia vs clinical practice: does it make a difference?

The Narcotrend is a computer-based EEG monitor designed to measure the depth of anaesthesia. The aim of the present study is to test the hypothesis that the intraoperative level of anaesthetic depth differs if decision-making is guided by Narcotrend monitoring or not. Forty-eight patients undergoing elective surgery were randomized to receive a Narcotrend-controlled propofol/remifentanil anaesthetic regimen or standard clinical practice. In the EEG group, anaesthesia was adjusted to achieve a Narcotrend level of D2-E0, which is recommended for moderate to deep anaesthetic depth for surgery. EEG values were recorded continuously every 20 s in both groups. Depending on data distribution, group comparisons of the EEG parameters, propofol plasma concentration, and recovery characteristics were performed by analysis of variance for repeated measurements or non-parametric statistics. About 62 (sd 29)% of the Narcotrend values were within the target level in the EEG group during maintenance of anaesthesia; this was true for 64 (26)% of the data in the non-EEG group. The variance of the Narcotrend data was significantly lower in the EEG group compared with the non-EEG group [median: 0.4 (range: 3.5) vs 0.6 (2.5); P = 0.048]. There was no difference in propofol or remifentanil dosage, propofol plasma concentrations, and time for extubation. Ten minutes after extubation, visual analogue scores for nausea indicated a lower incidence in the Narcotrend group [7 (15) vs 24 (34); P = 0.005]. Guidance of anaesthesia with the Narcotrend-monitor leads to fewer deviations from a defined target than clinical assessment of anaesthetic depth only. This results in lower scores of nausea in the immediate period after anaesthesia.

The effects of electromyographic activity on the accuracy of the Narcotrend® monitor compared with the Bispectral Index during combined anaesthesia

The Narcotrend is a monitor system for the assessment of depth of anaesthesia. The objective of this trial was to investigate the susceptibility of the Narcotrend to electromyographic (EMG) activity when compared with the Bispectral Index (BIS). We enrolled 33 patients undergoing major urological procedures under combined anaesthesia (thoracic epidural analgesia and general anaesthesia). Anaesthetic depth was assessed simultaneously by the BIS XP and Narcotrend. The intended anaesthetic depth ranged between 40 and 55 in the BIS and between D2 and D0 in the Narcotrend. BIS, but not Narcotrend, values correlated significantly (p < 0.0001) with EMG. BIS values between 70 and 80 occurred intermittently above an EMG activity of 35 dB, whereas the Narcotrend and the clinical signs remained unchanged during the period of elevated BIS values. None of the patients reported intra-operative awareness. Increased electromyographic activity does not affect Narcotrend values. Under combined anaesthesia, the Narcotrend monitor is more reliable when compared with the BIS regarding susceptibility to increased EMG activity.

Narcotrend (NT) monitoring depth of anesthesia in gynaecologic surgery: a comparison with Bispectral Index (BIS)

Giambartino, F.1; Pirri, S.1; Dones, F.1; Farbo, M.1; Lo Cascio, F.1; Scimeca, L.1; Alagna, G.1Author Information

Narcotrend monitoring prevents fluid overload during colonic surgery under combined anaesthesia

Narcotrend monitoring prevents fluid overload during colonic surgery under combined anaesthesia

Impact of the Narcotrend Index on propofol consumption and emergence times during total intravenous anaesthesia with propofol and remifentanil in children

The electroencephalographic Narcotrend Index (NI) is a measure of the hypnotic component of general anaesthesia. The purpose of this study was to evaluate the impact of Narcotrend guidance on propofol consumption and emergence times in children receiving total intravenous anaesthesia with propofol and remifentanil. Thirty children, aged 1-11 yr, scheduled for paediatric urological surgery were enrolled. Remifentanil was given to all patients at a constant infusion rate of 0.3 microg kg [-1] min[-1] throughout anaesthesia. Patients were randomly allocated to receive a continuous propofol infusion adjusted either according to a conventional clinical practice (Group C: n=15) or guided by Narcotrend monitoring (Group NI: n=15; target NI 60+/-5). All patients were connected to the Narcotrend Monitor, but in Group C the anaesthetist was blinded to the screen of the monitor. Propofol consumption (mg kg[-1]h[-1]) and emergence times (min) were the primary and secondary outcome measures. Propofol consumption (median [inter-quartile range]) was significantly lower in Group NI compared to Group C (NI: 7.0 [6.4--8.2] vs. C: 9.3 [8.3--11.0] mg kg[-1]h[-1]; P<0.001), whereas Log-Rank-analysis revealed no intergroup difference in emergence times (Group NI: mean [95% confidence interval (CI)] 12.8 [11.2--14.4] min; Group C: 16.4 [12.6--20.2] min; P=0.10). Haemodynamic variables remained stable within age-related limits, and there were no observations of adverse events, especially no clinical signs of intraoperative awareness in any patient. Narcotrend monitoring for guidance of propofol/remifentanil anaesthesia in children results in reduced propofol consumption compared to a conventional clinical practice.

Einfluss des Geschlechts auf Propofolverbrauch und Aufwachzeiten bei standardisierter Anästhesietiefe

We investigated gender differences of drug consumption and recovery times for propofol-remifentanil anaesthesia. Adult patients scheduled for minor orthopaedic surgery were randomised to receive a propofol-remifentanil anaesthesia controlled either by EEG monitoring (Narcotrend or BIS) or solely by clinical parameters. Anaesthesia was induced with remifentanil 0.4 microg/kg/min and a propofol target-controlled infusion (TCI) at 3.5 microg/ml. After intubation remifentanil was reduced to 0.2 microg/kg/min whereas propofol TCI was adjusted according to clinical parameters or to the following EEG target values: during maintenance to "D(0)" (Narcotrend) or "50" (BIS), 15 min before the end of surgery to "C(1)" (Narcotrend) or "60" (BIS). Recovery times were recorded and average normalised propofol consumption was calculated from induction and maintenance doses. A total of 60 male and 60 female patients completed the study. Gender differences were observed for recovery times (with standard practice) and for propofol consumption (with BIS monitoring). In the standard protocol group, propofol consumption was nearly identical for male and female patients whereas recovery times were significantly longer in the male group. In both EEG-guided groups propofol consumption was less for male patients while recovery times were slightly longer. In the group of female patients higher propofol TCI concentrations had to be used to reach the same BIS or Narcotrend values. With propofol-remifentanil anaesthesia, gender has impact on recovery times and propofol consumption. If the same amounts of propofol are applied, males awake later, with BIS or Narcotrend monitoring males receive less propofol for comparable EEG effects.

Application of Bispectral Index and Narcotrend index to the measurement of the electroencephalographic effects of isoflurane with and without burst suppression.

The Narcotrend monitor (MonitorTechnik, Bad Bramstedt, Germany) has recently been introduced as an intraoperative monitor of anesthetic state, based on a classification scheme originally developed for visual assessment of the electroencephalogram. The authors compared the performance of the Narcotrend index (software version 4.0) to the Bispectral Index (BIS, version XP; Aspect Medical Systems, Natick, MA) as electroencephalographic measures of isoflurane drug effect during general anesthesia. The authors observed 15 adult patients scheduled to undergo radical prostatectomy with a combined epidural-isoflurane general anesthesia technique. At least 45 min after induction of general anesthesia, during a phase of constant surgical stimulation, end-tidal isoflurane concentrations were varied between 0.5 and 2.0 multiples of minimum alveolar concentration, and the BIS and the Narcotrend index were recorded. The prediction probability (PK) was calculated for the BIS and the Narcotrend index to predict isoflurane effect compartment concentration for each measure. The correlation analysis of the BIS and the Narcotrend index with the isoflurane effect compartment concentration was obtained by pharmacodynamic modeling based on two sigmoidal curves to account for the discontinuity in both indices with the onset of burst suppression. The prediction probabilities were indistinguishable (BIS PK = 0.72 +/- 0.07 (mean +/- SD); range, 0.61-0.84; Narcotrend index PK = 0.72 +/- 0.10; range, 0.51-0.87), as were the correlations between the electroencephalographic measures and isoflurane effect compartment concentrations (BIS R = 0.82 +/- 0.12; Narcotrend index R = 0.85 +/- 0.09). The pharmacodynamic models for the BIS and the Narcotrend index yielded nearly identical results. The BIS and the Narcotrend index detected the electroencephalographic effects of isoflurane equally. Combining two fractional sigmoid Emax models adequately described the data before and after the onset of burst suppression.

The Correlation of the Bispectral Index with Propofol Effect Site Concentrations is not Altered by Epochs Indicated as Artefact-Loaded by Narcotrend

Artefact detection is an essential feature of automatic EEG monitoring systems used in anaesthesia. Clinical experience indicates that Narcotrend monitoring (MonitorTechnik, Bad Bramstedt, Germany, version 4.0) excludes more EEG epochs because of artefacts than bispectral index monitoring (BIS, Aspect Medical Systems, Newton, MA, version XP). Whether this increased exclusion of epochs is justified has not been investigated yet. Eighteen adult patients undergoing radical prostatectomy were investigated. Induction of anaesthesia was performed with a fentanyl bolus and a propofol infusion. Additionally, following intubation patients received 15 ml bupivacaine 0.5% epidurally. After a waiting period of 45 min depth of anaesthesia was varied two times by increasing and decreasing propofol concentrations. Narcotrend index, BIS values and calculated propofol effect site concentrations were automatically recorded at intervals of 5 s. We tested the hypothesis whether exclusion of artefacts detected by the Narcotrend monitor would possibly improve the prediction probability of the BIS monitor, justifying the necessity of artefact suppression. Simulated propofol effect site concentrations ranged from 2 microg/ml to 6 microg/ml. The Narcotrend monitor excluded a significantly higher percentage of epochs because of artefact detection (12.6 + 1.0%) than the BIS monitor (0.4 +/- 0.1%). The performance of BIS as an indicator of predicted propofol effect site concentrations did not differ when including (P(K) = 0.86 +/- 0.05) or excluding (P(K) = 0.85 +/- 0.04) the data pairs where Narcotrend monitor but not BIS monitor indicated an artefact. Artefacts were evenly distributed over the investigated range ofpropofol effect site concentrations. Exclusion of data pairs that were detected as artefacts by Narcotrend but not by BIS did not change the performance of bispectral index as an indicator of propofol effect site concentration.

Narcotrend and bispectral index monitoring during emergence from isoflurane anaesthesia

Narcotrend and bispectral index monitoring during emergence from isoflurane anaesthesia

Oversensitivity of artefact detection by Narcotrend monitoring compared to bispectral index monitoring

Oversensitivity of artefact detection by Narcotrend monitoring compared to bispectral index monitoring