Bispectral Index Score Research Articles

An Exploratory Study of Sevoflurane as an Alternative for Difficult Sedation in Critically Ill Children.

To analyze the effectiveness of inhaled sevoflurane in critically ill children with challenging sedation. Prospective case series. Two PICUs of university hospitals in Spain. Prospective observational study and exploratory investigation conducted in two PICUs in Madrid, Spain, over a 6-year period. Children treated with inhaled sevoflurane due to difficult sedation were included. Sevoflurane was administered via the anesthetic conserving device (AnaConDa) connected to a Servo-I ventilator (Maquet, Solna, Sweden). A morphine infusion was added to sevoflurane for analgesia. Demographic and clinical data, oral and IV sedatives, Sedation and Analgesic Clinical scores, and Bispectral Index Score monitoring were registered. Twenty-three patients with a median age of 6 months old were included. Fifty percentage of the patients had critical heart diseases. Sedative and analgesic drugs used before starting sevoflurane were mainly midazolam (63%) and fentanyl (53%). Six patients (32%) also received muscle relaxants. Sevoflurane was administered for a median of 5 days (interquartile range, 5.5-8.5 d). Median end-tidal sevoflurane concentration was 0.8% (interquartile range, 0.7-0.85%), achieved with an infusion rate of 7.5 mL/hr (5.7-8.6 mL/hr). After 48 hours of treatment, some sedative drugs could be removed in 18 patients (78%). Median Bispectral Index Score value prior to sevoflurane administration was 61 (interquartile range, 49-62), falling to 42 (interquartile range, 41-47; p < 0.05) after 6 hours of treatment. Six patients (26%) presented withdrawal syndrome after sevoflurane suspension, and all of them had received sevoflurane at least for 6 days. The main side effect was moderate hypotension in seven patients (30%). Inhaled sevoflurane appeared to be an effective sedative agent in critically ill children and can be useful in those patients on mechanical ventilation difficult to sedate with conventional drugs. It can be administered easily in the PICU with conventional ventilators using the AnaConDa system. Withdrawal syndrome may occur with prolonged treatment.

Effect of magnesium sulfate on anesthesia depth, awareness incidence, and postoperative pain scores in obstetric patients. A double-blind randomized controlled trial.

Objectives:To assess the effects of magnesium on the depth of anesthesia and to determine the effects of magnesium on incidence of awareness and postoperative pain after caesarean section.Methods:The study was designed as a double-blind, controlled, randomized study and conducted in Hacettepe University Hospital, Ankara, Turkey between January 2015 and March 2016. A total of 100 pregnant healthy women who were between 17 and 41 years old, ASA II, and scheduled for an elective cesarean section with general anesthesia were included in the study. After induction, sevoflurane was used for maintenance in Group S and desflurane in Group D (control groups). At Group S-M and Group D-M (study groups), magnesium infusion was started with sevoflurane and desflurane anesthesia respectively. Minimum alveolar concentration of sevoflurane and desflurane were kept constant. Bispectral index scores (BIS), fentanyl consumption and postoperative visual analogue scale (VAS) values were recorded. All of the patients had been followed-up for awareness until the postoperative first year.Results:Demographic variables of the patients were similar. BIS values were significantly higher in control groups throughout the operation (p<0.001). No significant difference was detected for intraoperative fentanyl consumption and awareness incidence. VAS values were significantly lower in study groups (p<0.05).Conclusion:Magnesium infusion provided significantly lower intraoperative BIS values and lower postoperative VAS scores. We believe that magnesium can be useful as an adjuvant to general anesthesia.

Comparative study of effective-site target controlled infusion with standard bolus induction of propofol for laryngeal mask airway insertion

Background: The laryngeal mask airway (LMA) is widely used in emergency medicine and surgical anesthesia. Several studies demonstrated induction of anesthesia with different plasma target-controlled infusion (TCI) of propofol for LMA insertion. However, there has been no study to compare the standard bolus propofol induction with the effective site TCI for LMA insertion. Objective: Compare the efficacy of induction of anesthesia with propofol for LMA insertion between the effective-site TCI, using 6 μg/mL, and the standard bolus propofol dose of 2.5 mg/kg in elective surgical patients. Methods: A randomized, prospective, single-blinded, clinical study was used for this study. Seventy-eight unpremedicated patients, American Society of Anesthesiologists (ASA) physical status I and II undergoing elective surgical procedure were randomly allocated between two groups. Group 1 received the standard bolus propofol dose of 2.5 mg/kg. Group 2 received effective site TCI (Schnider model) dose of 6 μg/mL for LMA insertion. The hemodynamics and anesthetic depth (Bispectral index score) were monitored and recorded during and immediately after LMA insertion. The number of insertion attempted, insertion quality score, induction time, and propofol doses used were recorded and compared between groups. Results: The success rate of first insertion attempt was equal in both groups (92.3%). There was no significant hemodynamic response difference between the groups during pre-induction, induction, insertion, and post insertion period. The BIS score was significantly lower during post insertion period in group 1 (51.4+11.0) than group 2 (58.4+3.2) (p=0.013). The propofol doses in group 2 were significantly lower than in group 1 (110.6+14.8 vs. 153.5+21.5) (p <0.001). Patients in group 2 required significantly more induction time than group 1 (146.9+42.3 vs. 103.4+33.6 (p <0.001). Conclusion: Propofol induction with TCI provided equal success rate as compared with standard bolus propofol induction for LMA insertion and insertion quality score. TCI significantly lowered the propofol consumption when compared with the standard 2.5 mg/kg propofol dose.

Effective dose of dexmedetomidine as an adjuvant sedative to peripheral nerve blockade in elderly patients.

BackgroundThe median effective dose (ED 50) of sedative dexmedetomidine adjuvant to peripheral nerve block (PNB) has not yet been verified in elderly patients. This study assessed the ED 50 of intravenous dexmedetomidine for sedation in elderly patients who were undergoing total knee arthroplasty (TKA) with PNB.MethodsForty‐two patients aged 65–85 years were included and stratified into two groups according to age: young‐old group (aged 65–74 years) and middle‐old group (aged 75–85 years). After the PNB was performed, a pre‐calculated dose of dexmedetomidine was administered for 10 min. The Observer's Assessment of Alertness/Sedation scale, bispectral index score, blood pressure and heart rate were recorded. ED 50 values of dexmedetomidine for adequate sedation were estimated by the up‐and‐down method of Dixon and probit regression.ResultsThe ED 50 of single‐dose dexmedetomidine adjuvant to PNB was 0.57 μg/kg (95% confidence interval [CI], 0.47–0.65) in the young‐old group and 0.38 μg/kg (95% CI, 0.28–0.46) in the middle‐old group. The ED 50 of dexmedetomidine differed significantly between the two groups (P < 0.001). In addition, no significant adverse hemodynamic or hypoxemic effects were noted.ConclusionWe determined the ED 50 for sedation using intravenous dexmedetomidine adjuvant to PNB in elderly patients. The ED 50 of dexmedetomidine in the middle‐old group decreased by 33% compared with that in the young‐old group with a mean age difference of 11 years between the two groups.

Relationship between brain computed tomography findings and bispectral index score in patients presenting with head trauma.

OBJECTIVE:Head trauma is one of the most important emergency health problems both in the world and in our country. The objective in our study is to (i) state the correlation between the findings of bispectral index score (BIS) and computed tomography (CT), which are used to evaluate the level of consciousness of patients with isolated head trauma, and (ii) investigate objective results about the patient’s level of consiousness/alertness according to the CT modality, which is used frequently.METHODS:This prospective study was carried out between 03.01.2014 and 09.01.2014 in the emergency department of Fatih Sultan Mehmet Education and Research Hospital. The average BIS scores were correlated with the Glasgow Coma Scale (GCS) point, the Canadian CT Head Rule major and minor criteria, and the pathologic findings in CT imaging. The patients’ demographic features, vital signs at admission, and arrival times at the hospital were investigated.RESULTS:In our study, 64 (31.7%) patients were female, and 138 (68.3%) patients were male. The mean BIS scores were 84.99±11.20 (86.05) and 93.78±3.80 (95.05) in patients with and without CT pathologies, respectively. The correlation between CT pathology and BIS scores was statistically significant: BIS scores were lower in patients with CT pathologies (p=0.001; p<0.01). There was a statistically significant positive correlation between the BIS and GCS scores (45.6%) (p<0.05).CONCLUSION:We showed that most head traumas occur after dangerous accidents, and according to the results, we can predict that males are more frequently affected than females. There was a statistically significant positive correlation between BIS scores and GCS points. In our study, the BIS scores were statistically significantly lower in patients with CT pathology than in patients without. We can predict that if the BIS score of the patient is low, then there will be the presence of pathology on CT imaging.

Correlation Between Observational Scales of Sedation and Comfort and Bispectral Index Scores

ContextWhen palliative care patients enter the phase of unconsciousness preceding death, it is standard practice to initiate or continue a subcutaneous infusion of an opioid plus or minus a sedative. The doses are determined somewhat empirically and adjustments are based on clinical assessment and observational measures of sedation and comfort. Following reports that these observational measures could be misleading, this study assesses their validity by comparing them with an objective measure of sedation, the Bispectral Index Score (BIS). ObjectiveThe objective of this study was to determine the validity of the Richmond Agitation and Sedation Scale (RASS) and the Patient Comfort Score (PCS) in assessing sedation and comfort in unconscious patients. MethodsForty eligible and consenting patients were monitored from the onset of unconsciousness (unresponsiveness) until death. Measures of sedation (RASS) and comfort (PCS) were made by the attending nurse every four hours. Correlation coefficients examined the relationship between fourth hourly RASS and PCS and time-matched BISs. ResultsA significant correlation was found between RASS and BIS and PCS and BIS. Sedation and comfort scores were concentrated at the lower end of the respective scales, whereas time-matched BISs were widely scattered with scores ranging from near full awareness to deep sedation. ConclusionsCompared with BIS, both RASS and PCS appear to be relatively blunt instruments at the lower end of their respective scales. Due caution should be taken interpreting and making clinical decisions based solely on the RASS and PCS and, by extension, other observational measures of patient comfort and sedation.

Risk factor analysis of additional administration of sedative agent and patient dissatisfaction in intravenous conscious sedation using midazolam for third molar extraction.

ObjectivesThe primary purpose of this study was to investigate the factors related with additional administration of sedative agent during intravenous conscious sedation (IVS) using midazolam (MDZ). The secondary purpose was to analyze the factors affecting patient satisfaction.Materials and MethodsClinical data for 124 patients who had undergone surgical extraction of mandibular third molar under IVS using MDZ were retrospectively investigated in this case-control study. The initial dose of MDZ was determined by body mass index (BMI) and weight. In the case of insufficient sedation at the beginning of surgery, additional doses were injected. During surgery, peripheral oxygen saturation, bispectral index score (BIS), heart rate, and blood pressure were monitored and recorded. The predictor variables were sex, age, BMI, sleeping time ratio, dental anxiety, Pederson scale, and initial dose of MDZ. The outcome variables were additional administration of MDZ, observer's assessment of alertness/sedation, intraoperative amnesia, and patient satisfaction. Descriptive statistics were computed, and the P-value was set at 0.05.ResultsMost patients had an adequate level of sedation with only the initial dose of MDZ and were satisfied with the treatment under sedation; however, 19 patients needed additional administration, and 13 patients were unsatisfied. In multivariable logistic analysis, lower age (odds ratio [OR], 0.825; P=0.005) and higher dental anxiety (OR, 5.744; P=0.003) were related to additional administration; lower intraoperative amnesia (OR, 0.228; P=0.002) and higher BIS right before MDZ administration (OR, 1.379; P=0.029) had relevance to patient dissatisfaction.ConclusionThe preoperative consideration of age and dental anxiety is necessary for appropriate dose determination of MDZ in the minor oral surgery under IVS. The amnesia about the procedure affects patient satisfaction positively.

Comparison of Intravenous Dexmedetomidine and Midazolam for Bispectral Index-Guided Sedation During Spinal Anesthesia.

BackgroundDespite the high frequency of hypotension during spinal anesthesia with proper sedation, no previous report has compared the hemodynamic effects of dexmedetomidine and midazolam sedation during spinal anesthesia. We compared the effects of bispectral index (BIS)-guided intravenous sedation using midazolam or dexmedetomidine on hemodynamics and recovery profiles in patients who underwent spinal anesthesia.Material/MethodsOne hundred and sixteen adult patients were randomly assigned to receive either midazolam (midazolam group; n=58) or dexmedetomidine (dexmedetomidine group; n=58) during spinal anesthesia. Systolic, diastolic, and mean arterial pressures; heart rates; peripheral oxygen saturations; and bispectral index scores were recorded during surgery, and Ramsay sedation scores and postanesthesia care unit (PACU) stay were monitored.ResultsHypotension occurred more frequently in the midazolam group (P<0.001) and bradycardia occurred more frequently in the dexmedetomidine group (P<0.001). Mean Ramsay sedation score was significantly lower in the dexmedetomidine group after arrival in the PACU (P=0.025) and PACU stay was significantly longer in the dexmedetomidine group (P=0.003).ConclusionsBIS-guided dexmedetomidine sedation can attenuate intraoperative hypotension, but induces more bradycardia, prolongs PACU stay, and delays recovery from sedation in patients during and after spinal anesthesia as compared with midazolam sedation.

Sedation with Dexmedetomidine or Propofol Impairs Hypoxic Control of Breathing in Healthy Male Volunteers

In contrast to general anesthetics such as propofol, dexmedetomidine when used for sedation has been put forward as a drug with minimal effects on respiration. To obtain a more comprehensive understanding of the regulation of breathing during sedation with dexmedetomidine, the authors compared ventilatory responses to hypoxia and hypercapnia during sedation with dexmedetomidine and propofol. Eleven healthy male volunteers entered this randomized crossover study. Sedation was administered as an intravenous bolus followed by an infusion and monitored by Observer's Assessment of Alertness/Sedation (OAA/S) scale, Richmond Agitation Sedation Scale, and Bispectral Index Score. Hypoxic and hypercapnic ventilatory responses were measured at rest, during sedation (OAA/S 2 to 4), and after recovery. Drug exposure was verified with concentration analysis in plasma. Ten subjects completed the study. The OAA/S at the sedation goal was 3 (3 to 4) (median [minimum to maximum]) for both drugs. Bispectral Index Score was 82 ± 8 and 75 ± 3, and the drug concentrations in plasma at the sedation target were 0.66 ± 0.14 and 1.26 ± 0.36 μg/ml for dexmedetomidine and propofol, respectively. Compared with baseline, sedation reduced hypoxic ventilation to 59 and 53% and the hypercapnic ventilation to 82 and 86% for dexmedetomidine and propofol, respectively. In addition, some volunteers displayed upper airway obstruction and episodes of apnea during sedation. Dexmedetomidine-induced sedation reduces ventilatory responses to hypoxia and hypercapnia to a similar extent as sedation with propofol. This finding implies that sedation with dexmedetomidine interacts with both peripheral and central control of breathing.

Changes in bispectral index score and cardiorespiratory function under constant rate infusion with alfaxalone in dogs

Changes in the cardiovascular and bispectral index score were evaluated in dogs subjected to constant rate infusion (CRI) with alfaxalone. Fifteen dogs were assigned to three groups of 5. Groups and doses of alfaxalone were as follows: group 1, 3 mg/kg for induction and 6 mg/kg/h for CRI; group 2, 3 mg/kg for induction and 8 mg/kg/h for CRI; and group 3, 3 mg/kg for induction and 10 mg/kg/h for CRI. CRI was maintained for 1 h. Respiratory rates and blood pressures showed minimal changes; however, mild tachycardia and mild hypoxemia occurred, especially in group 3. There were some disparities between bispectral index score, electromyography and pedal withdrawal reflex test when measuring anesthetic depth. Additional premedications and/or analgesic agents would be helpful to avoid adverse effects of alfaxalone and provide improved cardiopulmonary functions.

The effects of intravenous anesthetics on QT interval during anesthetic induction with sevoflurane.

Sevoflurane is known to prolong the QT interval. This study aimed to determine the effect of the interaction between intravenous anesthetics and sevoflurane on the QT interval. The study included 48 patients who underwent lumbar spine surgery. Patients received 3μg/kg fentanyl and were then randomly allocated to either Group T, in which they received 5mg/kg thiamylal, or Group P, in which they received 1.5mg/kg propofol, at 2min after administration of fentanyl injection for anesthetic induction. Vecuronium (1.5mg/kg) and sevoflurane (3% inhaled concentration) were administered immediately after loss of consciousness and tracheal intubation was performed 3min after vecuronium injection. Heart rate (HR), mean arterial pressure (MAP), bispectral index score (BIS), and the heart rate-corrected QT (QTc) interval on a 12-lead electrocardiogram were recorded immediately before fentanyl administration (T1), 2min after fentanyl injection (T2), immediately before intubation (T3), and 2min after intubation (T4). There were no significant differences between the two groups in baseline patient characteristics. BIS and MAP significantly decreased after anesthesia induction in both groups. At T3, MAP in Group T was higher than in Group P, while HR had reduced in both groups. The QTc interval was prolonged after anesthesia induction in Group T, but did not change at any time point in Group P. The QTc interval after anesthesia induction in Group T was longer than in Group P. We concluded that an injection of propofol could counteract QTc interval prolongation associated with sevoflurane anesthesia induction.

Moderate hypothermia and its effects in reducing the applied dose of anesthetics for patients with opium dependence in cardiac surgery: A randomized controlled trial

BackgroundAn increasing number of patients addicted to opium are experiencing awareness during coronary artery bypass surgery (CABG) as a result of tolerance to anesthetics.ObjectivesThis research was primarily intended to determine the potential diminishing effects of moderate hypothermia on anesthetic dosage and recall of anesthesia during the procedure.MethodsIn this double-blind randomized controlled trial, a total of 80 CABG candidates with known addiction to opium were divided into two groups: one normothermic (N) and the other moderately hypothermic (H), both undergoing induction as well as close monitoring from September 2014 to January 2016. The candidates were initially set for a target bispectral index (BIS) score of between 40 and 60. As the score rose to 60, an additional dose of propofol was administered, alongside rise in blood pressure and tear-shedding. To enhance the accuracy of our evaluation of anesthetic depth, we also used two questionnaires to test candidates’ recall filled with the assistance of a colleague 24 hours following surgery. Independent-samples t-test and chi-square test were used by SPSS v 18 for data analysis.ResultsEighty patients were studied in two groups of normothermic (N) (n = 40) and hypothermic (H) (n = 40). Given similar demographic data as well as the duration of surgery, we arrived at a propofol dose of 122.52±13.11 cc for normothermic patients and 101.28±14.06 cc for hypothermic subjects (p=0.001). As for fentanyl, the total required sum came up to 39.60±21.04 cc and 31.72±5.81 cc for the above-mentioned groups in order (p=0.025). Moreover, the post-operative interview showed that there was no report of a patient with memory recall following surgery.ConclusionsModerate hypothermia can substantially reduce the need for anesthetics in patients with addiction to opium when undergoing CABG surgery.Trial registrationThis study is registered in Iranian Registry of Clinical Trials with registration number of IRCT2014050513159N5.FundingThis research was supported financially by the Research Council of Mashhad University of Medical Sciences (grant number 920405).

Effects of music on sedation depth and sedative use during pediatric dental procedures

Study objectiveThe study aimed to investigate the effects of listening to music or providing sound isolation on the depth of sedation and need for sedatives in pediatric dental patients. DesignProspective, randomized, and controlled study. SettingTertiary, university hospital. PatientsIn total, 180 pediatric patients, American Society of Anesthesiologists physical status I and II, who were scheduled for dental procedures of tooth extraction, filling, amputation, and root treatment. InterventionsPatients were categorized into 3 groups: music, isolation, and control. During the procedures, the patients in the music group listened to Vivaldi’s The Four Seasons violin concertos by sound-isolating headphones, whereas the patients in the isolation group wore the headphones but did not listen to music. All patients were sedated by 0.1 mg/kg midazolam and 1 mg/kg propofol. During the procedure, an additional 0.5 mg/kg propofol was administered as required. Measurements and main resultsBispectral index was used for quantifying the depth of sedation, and total dosage of the propofol was used for sedative requirements. The patients’ heart rates, oxygen saturations, and Observer’s Assessment of Alertness and Sedation Scale and bispectral index scores, which were monitored during the operation, were similar among the groups. In terms of the amount of propofol used, the groups were similar. Prolonged postoperative recovery cases were found to be significantly frequent in the control group, according to the recovery duration measurements (P = .004). ConclusionsListening to music or providing sound isolation during pediatric dental interventions did not alter the sedation level, amount of medication, and hemodynamic variables significantly. This result might be due to the deep sedation levels reached during the procedures. However, listening to music and providing sound isolation might have contributed in shortening the postoperative recovery duration of the patients.

Effects of Xylazine or Acepromazine in dogs under constant rate infusion with alfaxalone

The anesthetic depth and cardiovascular effect of alfaxalone constant rate infusion in dogs premedicated with xylazine or acepromazine were evaluated. Ten dogs were randomly allocated into 2 groups. In group AA, dogs were premedicated with 0.02 mg/kg of intravenous acepromazine at 15 min before induction. In group XA 1.1 mg/kg of intravenous xylazine was premedicated at 5 min before induction. The anesthesia was maintained with 6 mg/kg/hr of alfaxalone after induction with 2 mg/kg alfaxalone in both groups. In both of groups, the qualities of induction were satisfactory without any adverse event, but adequate analgesia could not be provided, according to the withdrawal test. PaO2 and SaO2 implied a slight hypoxemia state in XA group, while those values of group AA were not significantly changed. The acepromazine and alfaxalone combination induce mild tachycardia. The bispectral index score were significantly decreased in group XA, compared with that in group AA. The premedication of xylazine before alfaxalone constant rate infusion in this study could provide adequate analgesia during 30 min, while the premedication with acepromazine could not.

Comparison of Hemodynamic Variations, Bispectral Index and Myoclonus Score of Propofol Dosage in Anesthesia Induced Patients

Aims Propofol is the most widely used intravenous anesthetic medication. It is necessary to assess the doses of the medication to determine proper anesthetic depth and to prevent its side-effects. The aim of this study was to compare 1 and 2.5mg/Kg doses of propofol in hemodynamic changes, myoclonus degree, and bi-spectral index (BIS) monitoring level in patients under anesthetic induction. Materials & Methods In the two-blind random clinical trial study, 92 patients being candidate for surgery wit general anesthesia induction were studied in Shahr-e Kord Kashani Center in 2013. The subjects, selected via simple sampling method, were randomly divided into two groups. The first and the second groups were received 1 and 2.5mg/kg doses of propofol, respectively. Hemodynamic, myoclonus, and BIS indices were measured at four different times in the groups. Data was analyzed by SPSS 17 using independent T and Chi-square tests, as well as repeated ANOVA and Fisher’s test. Findings There was no significant difference between the groups in the hemodynamic variables such as systolic and diastolic blood pressure, mean arterial blood pressure, pulse rate, and BIS (p>0.05). In addition, the change rates of the variables were the same. Nevertheless, there was a significant difference between the groups in the pulse change rate (p=0.032). There was no significant difference between the groups in myoclonus (p>0.05). Conclusion The hemodynamic changes and the changes in myoclonus degree and BIS are the same in 1 and 2.5mg/kg doses of propofol in the patients undergoing anesthetic induction.

A Comparison of the Effects of Low and High Doses of Aminophylline on Recovery Time and the Bispectral Index Score Following Iso flurane Anesthesia

Background: Aminophylline expedites the recovery from total intravenous and inhalation anesthesia. Objectives: The aim of this study was to evaluate low and high doses of aminophylline on extubation time, time to discharge from recovery, and the bispectral index score (BIS) in patients who received isoflurane anesthesia. Patients and Methods: After ethical approval and informed consent were obtained, this prospective, randomized, blinded clinical study was conducted in Sina hospital in Iran. Seventy-five patients who were scheduled for elective laparatomy surgery under isoflurane anesthesia were randomly allocated to receive either saline or 1 or 5 mg/kg of aminophylline (n = 25 for each) at the end of their anesthesia. The time to tracheal extubation and BIS after the administration of the study drug and the total time required until discharge from the post anesthesia care unit (PACU) were recorded. Results: Seventy-five patients completed the study. Compared to saline, patients who received 1 and 5 mg/kg of aminophylline demonstrated decreased extubation times (mean ± SD) (12.26 ± 7.33 vs. 11.15 ± 8.62 and 10.4 ± 4.78 min, respectively, P = 0.001) with higher BIS values (P = 0.001). However, the recovery and discharge times from the PACU were no different between the aminophylline and saline groups. Conclusions: The administration of high doses of aminophylline after laparatomy procedures with isoflurane anesthesia expedited the extubation time with no effects on discharge from the PACU.

Asleep-awake-asleep regimen for epilepsy surgery: a prospective study of target-controlled infusion versus manually controlled infusion technique

BackgroundAsleep-awake-asleep (AAA) protocol for epilepsy surgery is a unique opportunity to accurately map epilepsy foci involved in motor and eloquent areas, allowing the operator to optimize the resection. Two different application modes of intravenous anesthesia for AAA craniotomies are widely used: infusion by means of target-controlled infusion (TCI) and traditional manually-controlled infusion (MCI). We conducted this study to examine whether intravenous anesthesia using the TCI system with propofol and remifentanil would be a more effective method than MCI in AAA epilepsy surgery. MethodsThis prospective and single center study compared patients undergoing either TCI or MCI techniques for functional AAA epilepsy surgery. 35 cases used TCI including TCI-E (resection of epileptogenic foci in an eloquent area, n = 18) and TCI-M (resection of epileptogenic foci in a motor area, n = 17). Thirty-six cases used MCI including MCI-E (epileptogenic foci in an eloquent area, n = 16) and MCI-M (epileptogenic foci in a motor area, n = 20). Bispectral index value and hemodynamic profiles at different time points during the awake phase were recorded along with time for awakening and the occurrences of adverse events. ResultsThe TCI technique significantly shortened intraoperative awakening times during the third phase, TCI-E vs MCI-E 12.82 min ± 6.93 vs 29.9 min ± 9.04 (P = .000) and TCI-M vs MCI-M 16.8 min ± 5.19 vs 30.91 min ± 15.32 (P = .010). During the awake phase, the highest bispectral index score values appeared in the TCI-E group at all-time points. Mean arterial pressure and heart rate were more stable in the TCI-E group compared with the MCI-E group during the awake phase. Tachycardia and hypertension were most common in the MCI-E group (52.9% and 29.4%, P = .001 and P = .064). ConclusionWe found the superiority of TCI, which is faster intraoperative awakening and better hemodynamics along with secure airway management conditions. It is suggested that the TCI technique may be a feasible and effective technique and it might be a viable replacement of the MCI technique for AAA epilepsy surgery.

Effects of midazolam or tramadol premedication on early cognitive function in endoscopic retrograde cholangiopancreatography (ERCP): A randomized, controlled, double-blind study.

ObjectıveTo evaluate the sedative efficacy and effects on early period cognitive function of premedication in endoscopic retrograde cholangiopancreatography (ERCP).MethodsForty patients (18–70 years; American Society of Anesthesiology risk category I–III) undergoing elective ERCP were randomized to receive oral premedication with 0.15 mg/kg midazolam or 1 mg/kg tramadol. Cognitive function was determined by mini-mental test (MMT). Target scores for effective sedation were determined as a Bispectral index score of 70–90 and modified Ramsay Sedation Scale score (mRSS) of 2–4.ResultsGlobal MMT score was not significantly different between treatment groups at 60 min post-ERCP. A significant deterioration in the MMT subcategory of recall was determined in with midazolam versus tramadol. Level of sedation (mRSS) was higher in with midazolam compared with tramadol reaching statistical significance at 30 min after drug administration.ConclusıonsAlthough more effective sedation was obtained with midazolam in patients undergoing ERCP, there was a dysfunction in memory recall. It was concluded, however, that early cognitive functions were generally preserved with both drugs.

Sedation Monitoring and Management during Percutaneous Endoscopic Lumbar Discectomy.

Percutaneous endoscopic laser discectomy (PELD) is a painful intervention that requires deep sedation and analgesia. However, sedation should be light at some point because cooperation by the patient during the procedure is required for successful surgical treatment. Light sedation poses a problem for endotracheal intubation, while patients placed in the prone position during percutaneous endoscopic discectomy pose a problem for airway management. Therefore, under these conditions, sedation should be not deeper than required. Here we report the sedation management of three cases that underwent PELD, with a focus on deep and safe sedation that was monitored using bispectral index score and observer's assessment of alertness/sedation score.

Sedation in oral and maxillofacial day care surgery: A comparative study between intravenous dexmedetomidine and midazolam

Introduction:Sedation is an important component of day care oral and maxillofacial surgical procedures under local anesthesia. Although various sedative drugs in different regimens have been used for sedation, an ideal agent and regimen are yet to be established.Aim:The aim of this study is to compare the efficacy of intravenous (IV) dexmedetomidine and midazolam as a sedative agent for day care oral and maxillofacial surgical procedures.Settings:The study was conducted in the Department of Oral and Maxillofacial Surgery, SCB Dental College and Hospital, Cuttack, Odisha, India.Materials and Methods:A total of sixty adult patients of age group 18–65 years, of either sex were randomly selected equally in two groups for the study. One group named Group D received dexmedetomidine and the other named Group M received midazolam. Patients were evaluated for oxygen saturation (SPO2), respiration rate (RR), systolic blood pressure (SBP), diastolic blood pressure (DBP), Ramsay sedation score, bispectral index (BIS) score, amnesia, Aldrete score, relaxation during the surgery, and drug preference.Results:Midazolam was associated with greater amnesia. Dexmedetomidine was associated with lower heart rate, SBP, and DBP. There was no significant difference in SPO2, RR, Aldrete score, Ramsay sedation score, and BIS score between the two drugs. Patient preference and relaxation were more in dexmedetomidine group.Conclusion:IV dexmedetomidine is a comparable alternative to midazolam for sedation in day care oral and maxillofacial surgery under local anesthesia. It is the preferred drug when a lower heart rate and blood pressure or less amnesia is needed without any serious side effects.