Observer's Assessment Of Alertness/Sedation Research Articles

Dynamic Cortical Connectivity During Propofol Sedation in Glioma Patients.

The behavioral manifestations and neurophysiological responses to sedation can assist in understanding brain function after neurological damage, and can be described by cortical functional connectivity. Glioma patients may experience neurological deficits that are not clinically detectable before sedation. We hypothesized that patients with gliomas exhibit distinct cortical connectivity patterns compared to non-neurosurgical patients during sedation. This is a secondary analysis of a previously published prospective observational study. Patients scheduled for resection of supratentorial glioma (n=21) or a non-neurosurgical procedure (n=21) under general anesthesia were included in this study. Frontal electroencephalography (EEG) signals were recorded at different sedation levels as assessed by the Observer Assessment of Alertness/Sedation (OAA/S) score. Kernel principal component analysis and k-means clustering were used to determine possible temporal dynamics from the weighted phase lag index characteristics. Ten EEG connectivity states were identified by clustering (76% consistency), each with unique properties. At OAA/S 3, the median (Q1, Q3) occurrence rates of state 6 (glioma group, 0.110 [0.083, 0.155] vs. control group, 0.070 [0.030, 0.110]; P=0.008) and state 7 (glioma group, 0.105 [0.083, 0.148] vs. control group: 0.065 [0.038, 0.090]; P=0.001), which are dominated by beta connectivity, were significantly different between the 2 groups, reflecting differential conversion of the beta band between the left and right brain regions. In addition, the temporal dynamics of the brain's functional connectivity was also reflected in the transition relationships between metastable states. There were differences in EEG functional connectivity, which is dynamic, between the glioma and nonglioma groups during sedation.

Sedation for Colonoscopy Procedures Using Dexmedetomidine Versus Propofol-Fentanyl Infusions: A Prospective Randomized Controlled Trial.

Different anaesthetists for sedation or monitored anaesthesia care have been used for colonoscopy. The target of this research was the ability to perform colonoscopy under a painless degree of sedation and the prevalence of undesired proceedings. A total of 60 patients were randomly divided into two groups: Group D received dexmedetomidine and Group PF received propofol-fentanyl. Patients in both groups received the same infusion ratio. The minimum infusion amount of dexmetatomidine is (0.1 to 0.4 μg kg-1 h-1) in Group D, whereas fentanyl is administered at a rate of 0.01 to 0.05 μg kg-1 min-1 in the PF group during the approximately 45-min colonoscopy. Group D exhibited significantly lower modified Observer's Assessment of Alertness/Sedation (OAA/S) scores at intraoperative time points T1-T12. Group D also exhibited significantly lower visual analog scale scores for pain at intraoperative time points T4 and T7. The mean arterial pressure was significantly lower in Group D at intraoperative times T6-T8 and T11-T12, as well as upon admission to the post-anaesthesia care unit (PACU) and 30 min after admission to the PACU. The results of the ANOVA tests revealed a significantly lower heart rate in Group D. The respiratory rate exhibited a notable decrease during time intervals T8 and T10 in the PF group. The administration of dexmetatomidine and propofol-fentanyl during colonoscopy was found to be safe. In addition, dexmetatomidine may present significant benefits in this context because of its lower occurrence of adverse respiratory events.

Ultrasound-guided continuous fascia iliaca compartment block for perioperative pain management in elderly patients undergoing hip fracture surgery

To study the effect of ultrasound-guided fascia iliaca compartment block on perioperative analgesia and postoperative complications in geriatric patients with hip fractures. A total of 127 elderly patients undergoing hip fracture surgery from January 2021 to September 2021 were randomized to receive ultrasound-guided continuous fascia iliaca compartment block(group F) either intravenous analgesia control group(group C). There were 62 cases in group F, including 19 males and 43 females with an average age of (82.4±7.2) years old ranging from 66 to 95 years old, involving 25 femoral neck fractures and 37 femoral intertrochanteric fractures. There were 65 cases in control group, including 18 males and 47 females, with an average age of (81.4±8.7) years old ranging from 65 to 94 years old, involving 29 femoral neck fractures and 36 femoral intertrochanteric fractures. The visual analogue scale(VAS), minimental state examination (MMSE), observer's assessment of alertness/sedation(OAA/S) scale, modified Bromage score, postoperative complications and general conditions during hospitalization in two groups were observed. The resting and exercise VAS at 30 min after block, anesthesia placement and 6, 24 and 48 h after surgery were lower than those in group C(P<0.05). In group F, MMSE scores at 12 h before surgery, and 1, 3 d after surgery and OAA/S scores at 3 d after surgery were higher than those in group C(P<0.05). The incidence of adverse effects and the number requiring additional analgesia were lower than those in group C(P<0.05). Group F had better perioperative analgesia satisfaction and hospital stay than group C(P<0.05). But there was no significant difference regarding Bromage score and 30-day mortality between two group(P>0.05). Ultrasound-guided continuous fascia iliacus space block was safe and effective for elderly patients with hip fracture, and could significantly reduce perioperative pain, improve postoperative cognitive function, and reduce postoperative complications, thereby shortening hospital stay and improving the quality of life during hospitalization.

Prevalence and Risk Factors of Postprocedure Depression in Patients with Atrial Fibrillation after Radiofrequency Ablation.

Recent studies have shown a bidirectional relationship between atrial fibrillation (AF) and psychological depression. However, little is known about the prevalence of postprocedure depression (PPD) in patients with AF at the time of radiofrequency (RF) ablation. To describe the prevalence and identify risk factors for PPD. This was a prospective cohort study, including 428 AF patients who were willing to undergo the first catheter ablation in our hospital from 1st April to 30th December 2019. The primary outcome was PPD, which was determined by Hospital Anxiety and Depression Scale-Depression. The prevalence of PPD was 16.8% (72/428) in our cohort, without difference between men (16.0%, 41/256) and women (18.0%, 31/172) (P = 0.586) but with a great difference among different age groups (P = 0.016). On the univariable binary logistic regression analysis, age, a history of coronary heart disease, Observer's Assessment of Alertness/Sedation (OAA/S) score when ablating at the specific position, and OAA/S score when pulling out the catheter sheath were associated with PPD. Subsequent multivariable logistic regression analysis indicated only age (OR 0.96, 95% CI: 0.94-0.99, P < 0.01) and OAA/S score when ablating at the specific position (OR 0.58, 95% CI: 0.39-0.88, P = 0.01) were independently associated with PPD. PPD is common in patients with AF after RF ablation. Younger age and lower OAA/S score when ablating at the specific position are its most significant risk factors. Intensive management of sedation may be of great importance for reducing PPD. This trial is registered with the Chinese Clinical Trial Registry (ChiCTR2200057810).

452 Booting Up the Brain: Intracranial Electroencephalography Reveals Cognitive Network Dynamics During Anesthesia Emergence

INTRODUCTION: The dynamic interplay between several large-scale brain networks is thought to underlie human consciousness. The default mode network (DMN) governs internal thought during rest, the central executive network (CEN) drives goal-directed problem solving, and the salience network (SN) detects and integrates new stimuli during the transition between resting and cognitively active states. While scalp electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) have elucidated much about these networks in steady states, intracranial EEG (iEEG) dynamics during state transitions remain largely unclear. METHODS: Seven patients with medically refractory epilepsy underwent robot-assisted stereotactic placement of depth electrodes for epileptic focus localization. Recordings from 422 total iEEG contacts representing 49 distinct cognitive network nodes were obtained during anesthesia emergence. Local-field dynamics and Observer’s Assessment of Alertness/Sedation (OAAS) scale state were analyzed in 20s clips for complexity, functional connectivity (FC), and graph communicability metrics. RESULTS: Signal complexity as represented by mean multiscale sample entropy (MSE) of SN and DMN nodes increases significantly during emergence from anesthesia (P &lt; 0.05), driven by a shift from low- to mid-frequency power in key nodes. Intermediate consciousness states demonstrated higher mean MSE and participation coefficient, representing early integrative network behavior, before reaching an optimal balance of segregation and integration at wakefulness. During emergence, between-network FC increased most strongly between SN and CEN nodes. Communicability of SN nodes increased during emergence, driven predominately by increasing communicability of right anterior insula. CONCLUSIONS: Intracranial electroencephalographic recording of brain activity during anesthesia emergence demonstrates a complex but quantifiable interplay of default mode, central executive, and salience network hubs. There may be a greater than previously understood role of right anterior insula in gating transitions in consciousness states.

The effect of playing music and mother's voice to children on sedation level and requirement during pediatric magnetic resonance imaging

BackgroundMagnetic resonance imaging examinations frequently cause anxiety and fear in children. The objective of this study was to investigate the effects of listening to music sound, the mother's voice, and sound isolation on the depth of sedation and need for sedatives in pediatric patients who would undergo MRI. MethodsNinety pediatric patients aged 3 to 12 years who were planned for imaging in the MRI unit were randomly assigned to isolation group (Group I), musical sound group (Group II), and mother's voice group (Group III). We evaluated patients' anxiety and sedation levels via the Observer's Assessment of Alertness/Sedation (OAA/S) ResultsHeart rate, oxygen saturation, OAA/S, and Ramsey scores during the procedure were not significantly different among the groups (p>0.05). The mean amount of propofol and total propofol consumption was statistically lower in the mother's voice group than in the isolation and music sound groups (p<0.001). Mean propofol amount and total propofol consumption were not significantly different in isolation and music sound groups (p>0.05). No difference was found between the groups regarding the time it took for the patients' Modified Aldrete score to reach 9 (p>0.05). ConclusionsIn pediatric patients, listening to the mother's voice during MRI decreased the total sedative requirement consumed without increasing the depth of sedation.

Effect of real-time binaural music on sedation with dexmedetomidine during spinal anesthesia: A triple-arm, assessor-blind, randomized controlled trial

Study objectiveBinaural audio induces sedation and reduces pain and anxiety in surgical patients. This study tested the hypothesis that dexmedetomidine requirement for adequate sedation during spinal anesthesia would be lower in patients listening to music with binaural sound than that in patients listening to plain or no music. DesignA triple-arm, assessor-blind, randomized controlled study. SettingOperating room. PatientsOne hundred and eighty-nine patients undergoing orthopedic surgery under spinal anesthesia. InterventionsPatients were randomly assigned to music with binaural sound, plain music, or no music groups. Dexmedetomidine was infused for sedation during surgery. The loading infusion rate was 6 μg/kg predicted body weight (PBW)/h, followed by continuous infusion at 0.6 μg/kg PBW/hr. Loading was stopped after achieving adequate sedation, defined as the Observer's Assessment of Alertness/Sedation (OAA/S) scale score of 3. Infusion rate was adjusted every 30 min per the OAA/S scale. MeasurementsPrimary outcomes were the difference in the dexmedetomidine loading dose adjusted for the patient's PBW between (1) the binaural and plain music groups and (2) the binaural and control groups. Secondary outcomes were the total dose and total loading time of dexmedetomidine; Patient State Index; relative powers of the alpha, theta, and delta bands; recovery from sedation; and patient satisfaction score. Main resultsThe final analyses included 184 patients. The PBW-adjusted dexmedetomidine loading dose was significantly lower in patients listening to music with binaural sound (1.15 ± 0.30 μg/kg PBW) than that in patients without music (1.33 ± 0.33 μg/kg PBW; mean difference, 0.18 μg/kg PBW; 95% confidence interval [CI], 0.06 to 0.29; P = 0.002). However, the difference was not statistically significant when compared with the plain music group (1.26 ± 0.36 μg/kg PBW; mean difference, 0.11 μg/kg PBW; 95% CI, −0.01 to 0.23; P = 0.070). Dexmedetomidine total dose, recovery from sedation, and patient satisfaction score showed no difference among the three groups. ConclusionsCompared with no music, music with binaural sound reduced the dexmedetomidine loading dose; however, this sedative-sparing effect of binaural sound was not found when compared to plain music.

Total intravenous anesthesia induced and maintained by a combination of remimazolam and remifentanil without a neuromuscular blocking agent: a prospective, observational pilot study

BackgroundA novel short-acting benzodiazepine, Remimazolam, has recently been approved for general anesthesia and sedation. Hence, we investigated the feasibility and safety of remimazolam during the induction and maintenance of general anesthesia without using a neuromuscular blocking agent (NMBA) in patients undergoing hysteroscopic surgery.MethodsThis prospective observational study included 38 patients undergoing hysteroscopic surgery. Remimazolam and remifentanil were the main anesthetic agents without an NMBA, and a supraglottic airway was inserted to protect the airway. The induction time, amount of each anesthetic agent used during anesthesia, intraoperative bispectral index (BIS) hemodynamic parameters, and recovery profiles were measured.ResultsGeneral anesthesia was successfully administered to 37 patients using remimazolam and remifentanil without NMBA. The induction doses of remimazolam and remifentanil were 0.4 mg/kg (interquartile range [IQR] 0.34–0.47 mg/kg) and 1.07 μg/kg (IQR, 0.90–1.29 μg/kg), respectively. Additionally, the maintenance doses of remimazolam and remifentanil were 1.14 mg/kg/h (IQR, 0.88–1.55 mg/kg/h) and 0.06 μg/kg/min (IQR, 0.04–0.08 μg/kg/min), respectively. Intraoperative BIS values had risen temporarily > 60 in eight patients (21.6%) despite administration of 2 mg/kg/h of remimazolam; thus, they were treated with supplementary midazolam. The median recovery time was 7 min (IQR, 5–8 min) after 40 min (IQR, 40.0–57.5 min) of total mean anesthesia time. There was no correlation between the infusion dose of remimazolam and recovery profiles, such as recovery time, final BIS of anesthesia, modified observer assessment of alertness/sedation (OAA/S) scale or post-anesthesia recovery (PAR) score when arriving at the PACU, and length of stay in the PACU (all P > 0.05).ConclusionRemimazolam can be combined with remifentanil without an NMBA in female patients who undergo hysteroscopic surgery, during which a supraglottic airway is a feasible method to protect the airway.Trial registrationThe study protocol was registered at ClinicalTrials.gov (NCT05025410) on 27/08/2021.

Propofol with or without fentanyl for pain relief after transrectal ultrasound-guided prostate (TRUS-P) biopsy: a randomized controlled study

BackgroundPostoperative pain from transrectal ultrasound-guided prostate (TRUS-P) biopsy under sedation is often mild. Benefit of opioids used during sedation is controversial. ObjectiveThe objective was to compare numeric rating scale (NRS) score at 30 minutes after TRUS-P biopsy between patients receiving propofol alone or with fentanyl. MethodsWe randomly allocated 124 patients undergoing TRUS-P biopsy to receive either fentanyl 0.5 mcg.kg-1 (Group F) or normal saline (Group C). Both groups received titrated propofol sedation via Target-controlled infusion (TCI) with Schneider model until the Observer's Assessment of Alertness/Sedation (OAA/S) scale 0–1 was achieved. Hemodynamic variables, patient movement, postoperative pain score, patient and surgeon satisfaction score were recorded. ResultsOverall, most patients (97.5%) had no to mild pain. Group F had significantly lower median NRS score at 30 minutes compared to Group C (0 [0, 0] vs. 0 [0, 0.25], p = 0.039). More patients in Group C experienced pain (90% vs. 75.8%, p = 0.038). Perioperative hypotension was higher in group F (81.7%) compared to Group C (61.3%) (p = 0.013). Thirty-five (56.5%) patients in Group F and 25 (42.7%) patients in Group C had movement during the procedure (p = 0.240). Surgeon’s satisfaction score was higher in Group F (10 [9, 10]) than Group C (9 [9, 10]) (p = 0.037). ConclusionCombining low dose fentanyl with TCI propofol sedation may provide additional benefit on postoperative pain after TRUS-P biopsy, but results in perioperative hypotension. Fentanyl may attenuate patient movement during the procedure, which leads to greater surgeon’s satisfaction.

Analysis of influence factors of pharmacodynamics of propofol with target-controlled infusion during anesthetic recovery period.

To explore the pharmacodynamic (PD) characteristics of propofol during anesthetic recovery period with target-controlled infusion (TCI), and to identify the clinical variables related to the PD parameters. 20 patients scheduled for otolaryngology surgery were enrolled. After the surgery was finished, target effect site concentration was gradually decreased, blood samples were measured at 7 time points and the differences between the target and measured plasma concentration were compared. Observer's assessment of alertness/sedation (OAA/S) and Narcotrend index (NI) were used as two PD indicators by fitting sigmoid Emax model. Correlations between PD parameter and clinical variables were evaluated. Performance of the TCI system showed a positive bias at the end of the anesthesia sedation period and a negative bias in the anesthetic recovery period. PD parameters (EC50, r) calculated with OAA/S and NI were significantly different, EC50 of OAA/S was lower than EC50 of NI (1.53 ± 0.70 vs. 2.16 ± 0.99 µg/mL), r of OAA/S was higher than r of NI (57.07 ± 56.39 vs. 4.35 ± 4.42). Propofol dosage and hemodynamic parameters were significantly correlated with EC50 (OAA/S), lean body weight and gender were significantly correlated with EC50 (NI). NI provided a more stable and adequate assessment of the depth of anesthesia than OAA/S, and the influence factors should be taken into account for precise dosing.

Sevoflurane versus PRopofol combined with Remifentanil anesthesia Impact on postoperative Neurologic function in supratentorial Gliomas (SPRING): protocol for a randomized controlled trial

BackgroundPatients with intracranial tumors are more sensitive to anesthetics than the general population and are therefore more susceptible to postoperative neurologic and neurocognitive dysfunction. Sevoflurane or propofol combined with remifentanil are widely used general anesthetic regimens for craniotomy, with neither regimen shown to be superior to the other in terms of neuroprotective efficacy and anesthesia quality. There is no evidence regarding the variable effects on postoperative neurologic and neurocognitive functional outcome under these two general anesthetic regimens. This trial will compare inhalational sevoflurane or intravenous propofol combined with remifentanil anesthesia in patients with supratentorial gliomas and test the hypothesis that postoperative neurologic function is equally affected between the two regimens.MethodsThis is a prospective, single-center, randomized parallel arm equivalent clinical trial, which is approved by China Ethics Committee of Registering Clinical Trials (ChiECRCT-20,160,051). Patients with supratentorial gliomas diagnosed by magnetic resonance imaging will be eligible for the trial. Written informed consent will be obtained before randomly assigning each subject to either the sevoflurane-remifentanil or propofol-remifentanil group for anesthesia maintenance to achieve an equal-desired depth of anesthesia. Intraoperative intervention and monitoring will follow a standard anesthetic management protocol. All of the physiological parameters and other medications administered during the intervention will be recorded. The primary outcome will be neurologic function change assessed by National Institute of Health Stroke Scale (NIHSS) within 4 h after general anesthesia when observer’s assessment of alertness/sedation (OAA/S) reaches 4. Secondary outcomes will include NIHSS and modified NIHSS change 1 and 2 days after general anesthesia, hemodynamic stability, intraoperative brain relaxation, quality of anesthesia emergence, quality of anesthesia recovery, postoperative cognitive function, postoperative pain, postoperative neurologic complications, as well as perioperative medical expense.DiscussionThis randomized equivalency trial will primarily compare the impacts of sevoflurane-remifentanil and propofol-remifentanil anesthesia on short-term postoperative neurologic function in patients with supratentorial gliomas undergoing craniotomy. The exclusion criteria are strict to ensure that the groups are comparable in all aspects. Repeated and routine neurologic evaluations after operation are always important to evaluate neurosurgical patients’ recovery and any newly presenting complications. The results of this trial would help specifically to interpret anesthetic residual effects on postoperative outcomes, and perhaps would help the anesthesiologist to select the optimal anesthetic regimen to minimize its impact on neurologic function in this specific patient population.Trial registrationThe study was registered and approved by the Chinese Clinical Trial Registry (Chinese Clinical Trial Registry, ChiCTR-IOR-16009177). Principle investigator: Nan Lin (email address: linnan127@gmail.com) and Ruquan Han (email address: hanrq666@aliyun.com) Date of Registration: September 8th, 2016. Country of recruitment: China.

Efficacy of transcutaneous electrical acupoint stimulation combined with general anesthesia for sedation and postoperative analgesia in minimally invasive lung cancer surgery: A randomized, double-blind, placebo-controlled trial.

BackgroundMultimodal opioid‐sparing analgesia is a key component of an enhanced recovery pathway after surgery that aims to improve postoperative recovery. Transcutaneous electrical acupoint stimulation (TEAS) is assumed to alleviate pain and anxiety and to modify the autonomic nervous system. This study aimed to determine the efficacy of TEAS for sedation and postoperative analgesia in lung cancer patients undergoing thoracoscopic pulmonary resection.MethodsA total of 80 patients were randomized into two groups: the TEAS group and the sham TEAS combined with general anesthesia group. Postoperative pain levels at six, 24, 48 hours, and one month after surgery were measured using the visual analogue scale (VAS). Bispectral index (BIS) score during the TEAS prior to anesthetic induction, Observer's Assessment of Alertness/Sedation (OAAS) score, sufentanil consumption during postoperative patient‐controlled intravenous analgesia (PCIA), number of total and effective attempts of PCIA pump use, and incidence of postoperative nausea and vomiting were recorded and analyzed statistically.ResultsPatients in the TEAS group had significantly lower VAS scores at six, 24, and 48 hours after surgery (P < 0.01); lower BIS scores at 10, 20, and 30 minutes before induction (P < 0.01); lower levels of postoperative sufentanil consumption; lower number of PCIA attempts and effective rates (P < 0.01); lower incidences of nausea at 0, six, 24, and 48 hours; and lower incidence of vomiting at 24 hours after surgery (P < 0.05). The postoperative OAAS scores were similar between the groups.ConclusionsTEAS could be a feasible approach for sedation and postoperative analgesia in thoracoscopic pulmonary resection.

Recovery characteristics in patients undergoing short Gynaecological day care procedures under sedation with Dexmedetomidine vs Propofol infusion : Double blind Randomized controlled trial

Background and Aims: Postoperative psychomotor dysfunction is one of the deciding factors for discharge after daycare surgeries. Sedation for daycare procedures is commonly done using propofol and dexmedetomidine. Hence, we decided to study the recovery characteristics of dexmedetomidine and propofol in patients undergoing short gynaecological day care procedures. Methods: After getting informed consent, 40 patients aged between 18 to 65 years and ASA physical status 1 and 2 undergoing short gynaecological procedures were included for this double-blind prospective randomized controlled trial. All patients were educated about psychomotor tests preoperatively. Patients were randomized into two groups, Group P (propofol) and Group D (dexmedetomidine). Sedation was given using propofol or dexmedetomidine according to the group and titrated to achieve observer's assessment of alertness/sedation (OAA/S) scale 2-3. Recovery characteristics were assessed by modified Aldrete score, time to sit without support, finger tapping test and visual-spatial capacity memory test. Results: Demographic variables, baseline finger tapping test and visual-spatial capacity memory test, duration and type of surgery were comparable. All forty patients tolerated the procedure with no signs of respiratory depression.Time to achieve modified Aldrete score 9- 10 was significantly more in Group P compared to Group D ( 5.6±1.4min vs 4.0±1.4min; P=0.002), while time to sit without support was significantly less in Group P ( 5.6±1.4min vs 4.0±1.4min; P=0.002). Psychomotor tests during recovery and patient satisfaction score were comparable between the groups. Conclusion: Dexmedetomidine and propofol have been found to have comparable recovery characteristics in daycare short gynaecological surgeries.

Application of Dexmedetomidine versus Propofol in elderly patient undergoing transurethral resection of the prostate

Objective To investigate the efficiency and safety of Dexmedetomidine as adjuvant to local anesthetics in elderly patient undergoing transurethral resection of the prostate. Methods Sixty elderly patients undergoing selective transurethral resection of the prostate were randomly divided into the Dexmedetomidine group and the Propofol group(n=30, each). After block level of spinal anesthesia was determined, Dexmedetomidine(a bolus dose of 0.5 μg/kg for 10 minutes, then continuous injection of 0.2-0.4 μg·kg-1·h-1)or Propofol(initial plasma concentration of 0.5 mg/L, after getting equal to an effect compartment drug concentration, plasma concentration was gradually increased by 0.1 mg/L)was injected with an infusion pump.Observation items were recorded, including the onset time[observer's assessment of alertness/sedation(OAA/S)≤3 points], blood pressure, heart rate, respiratory rate, pulse oxygen saturation, end-tidal carbon dioxide partial pressure, bispectral index value(BIS), and OAA/S score as well as adverse events and patients' satisfaction to sedation. Results The OAA/S score after 20 minutes of drug injection was lower in the Propofol group than in the Dexmedetomidine group(3.0±0.5 scores vs.3.5±0.6 scores, t=2.300, P=0.030). The systolic pressure levels were lower in the Propofol group than in the Dexmedetomidine group after 30 minutes and 40 minutes of drug injection(107.6±11.2 mmHg vs.119.2±16.4 mmHg, 106.7±9.6 mmHg vs.121.2±18.3 mmHg, 1 mmHg=0.133 kPa, t=2.151 and 2.555, P=0.041 and 0.017). The diastolic pressure was lower in the Propofol group than in the Dexmedetomidine group after 10 minutes of drug injection(69.8±6.7 mmHg vs.78.0±10.1 mmHg, t=2.462, P=0.021). The incidence of bradycardia was higher in the Dexmedetomidine group than in the Propofol group(20.0% or 6/30 vs.0.0% or 0/30, χ2=6.667, P=0.010). The incidences of respiratory depression and involuntary movement were lower in the Dexmedetomidine group than in the Propofol group(0.0% or 0/30 vs.13.3% or 4/30, 0.0% or 0/30 vs.30.0% or 9/30, χ2=4.286 and 10.588, P=0.038 and 0.001). Conclusions Compared with the conventional Propofol, Dexmedetomidine has a definite sedative effect in elderly patients undergoing transurethral resection of the prostate under spinal anesthesia, with peace and cooperation, greater stability of blood pressure, without breath depression, but with higher incidence of bradycardia. Key words: Dexmedetomidine; Propofol; Transurethral resection of prostate

Previously published drug interaction models predict loss of response for transoesophageal echocardiography sedation well but not response to oesophageal instrumentation

Response surface models (RSMs) were used to predict effects of multiple drugs interactions. Our study was aimed to validate accuracy of the previous published volunteer models during transoesophageal echocardiography (TEE). This is a cross-sectional study with 20 patients scheduled for transesophageal echocardiography in Taipei Veterans General Hospital, Taiwan. Effect-site concentration pairs of alfentanil and propofol were recorded and converted to equivalent remifentanil and propofol effect-site concentrations. Observer’s Assessment of Alertness/Sedation (OAA/S) scores were assessed every 2 minutes. Using these data, previous published models of loss of response (LOR), intolerable ventilatory depression (IVD), and loss of response to esophageal instrumentation (LREI) were then estimated. Accuracy of prediction is assessed by calculating the difference between the true response and the model-predicted probability. Clinical events such as interruption of TEE were recorded. The average procedure time was 11 minutes. Accuracy for prediction of LOR and LREI is 63.6% and 38.5%, respectively. There were four patients experienced desaturation for less than 1 minute, which were not predicted by IVD model, and one interruption of TEE due to involuntary movement. The previous published drug-interaction RSMs predict LOR well but not LREI for TEE sedation. Further studies using response surface methodology are needed to improve quality for TEE sedation and clinical implementation.

Effects of propofol sedation on psychological stress in surgical patients under epidural

To explore the effects of propofol sedation on psychological stress in patients undergoing surgery under epidural anesthesia. Sixty patients scheduled to undergo elective ileostomy closure under epidural anesthesia were randomized into propofol sedation group and control group (n=30). The patients in the sedation group received a loading dose of propofol of 0.6 mg·kg- 1· h- 1 followed by a maintenance dose with continuous infusion of 3 mg·kg- 1· h- 1 given after the Observer's Assessment of Alertness/Sedation (OAA/S) score reached 2-3. An equivalent volume of normal saline was administered in patients in the control group. The patients' preoperative and intraoperative anxiety scores were assessed with the State Anxiety Inventory (SAI) on the day before and on the first day after the surgery, respectively. The mean blood pressure (MBP), heart rate (HR), SpO2, OAA/S, and the indicators of psychological stress of brain functional state of the patients (including the wavelet index [WLi], anxiety index [ANXi], comfortable index [CFi] and pain index [Pi]) were recorded at 5 min after entering the operating room (T0), at the time of lumbar puncture (T1) and change to supine position after the puncture (T2), at 20 s (T3), 40 s (T4), and 60 s (T5) after intravenous administration, and at 2 min (T6), 4 min (T5), 6 min (T8), 8 min (T9), 10 min (T10) and 40 min (T11) after skin incision. The patient's satisfaction with anesthesia was assessed with the Visual Analog Scale (VAS) score on the first day after the operation. Serum cortisol level was measured before anesthesia and at the end of operation to calculate the changes in cortisol level. The two groups of patients were comparable for preoperative SAI scores (P&gt;0.05); The patients in the sedation group appeared to have lower intraoprative SAI scores, but this difference was not statistically significant (P=0.05). MBP, HR, and SpO2 at the time points from T6 to T10 and OAA/S, WLi, ANXi, CFi, and Pi at the time points from T6 to T11 were significantly lower in the sedation group (all P &lt; 0.05), and these parameters were not significantly different between the two groups at the other time points (all P&gt;0.05). The patient satisfaction scores were significantly higher in the sedation group (Z=2.07, P &lt; 0.05). Compared with the preoperative levels, serum cortisol level at the end of the operation was increased in the sedation group but lowered in the control group, and the variations of serum cortisol level differed significantly between the two groups (t=4.75, P &lt; 0.01). Intraoperative propofol sedation can alleviate the patients' anxiety, improve the comfort level, and lessen physiological stress during surgeries under epidural anesthesia.

Effect of remifentanil during drug-induced sleep endoscopy in patients with obstructive sleep apnea.

During drug-induced sleep endoscopy (DISE) in patients with obstructive sleep apnea, the increased depth of propofol anesthesia is related to the increased collapsibility of the upper airway with dose-dependent. We examined the effect of remifentanil on propofol concentration during DISE. In a prospective randomized trial, 56 adult patients were divided into remifentanil-propofol (n = 28) and propofol alone (n = 28) groups. Anesthesia was administered using a target-controlled infusion system. In the remifentanil-propofol group, 0.5ng/ml remifentanil was administered prior to propofol infusion and its concentration maintained; thereafter, in the propofol alone group, normal saline was injected instead of remifentanil. Propofol was infused at a concentration of 1.5μg/ml after the target concentration of remifentanil was reached. In both groups, the concentration of propofol was increased by 0.5μg/ml if the degree of sedation was not sufficient. The sedation level was targeted at observer's assessment of alertness/sedation (OAA/S) scale 3. The mean propofol concentration was 2.87 ± 0.60μg/ml in the remifentanil-propofol group, which was lower than that in the propofol alone group (3.38 ± 0.72μg/ml, P < 0.001). The time until sufficient sedation to perform DISE was shorter in the remifentanil-propofol group (P < 0.001). Apnea-hypopnea index and the lowest peripheral capillary oxygen saturation (SpO2) during polysomnography showed no statistical difference between groups (P > 0.05). The lowest SpO2 and VOTE classification during DISE were also not statistically different (P > 0.05). Use of remifentanil during DISE reduces the target concentration of propofol required for patient sedation to perform DISE without respiratory depression.

Randomized Clinical Trial Comparing Procedural Amnesia and Respiratory Depression Between Moderate and Deep Sedation With Propofol in the Emergency Department.

The objective was to determine if there is a difference in procedural amnesia and adverse respiratory events (AREs) between the target sedation levels of moderate (MS) and deep (DS) procedural sedation. This was a prospective, randomized clinical trial of consenting adult patients planning to undergo DS with propofol between March 5, 2015, and May 24, 2017. Patients were randomized to a target sedation level of MS or DS using the American Society of Anesthesiologist's definitions. Drug doses, vital signs, observer's assessment of alertness/sedation (OAAS) score, end-tidal CO2 (ETCO2 ), and the need for supportive airway maneuvers (SAMs; bag-valve mask use, repositioning, and stimulation to induce respirations) were monitored continuously. A standardized image was shown every 30 seconds starting 3 minutes before the procedure continuing until the patient had returned to baseline after the procedure. Recall and recognition of images were assessed 10 minutes after the sedation. Subclinical respiratory depression (RD) was defined as SaO2 ≤ 91%, change in ETCO2 ≥ 10 mm Hg, or absent ETCO2 at any time. The occurrence of RD with a SAM was defined as an ARE. Patient satisfaction, pain, and perceived recollection and physician assessment of procedure difficulty were collected using visual analog scales (VASs). Data were analyzed with descriptive statistics and Wilcoxon rank-sum test. A total of 107 patients were enrolled: 54 randomized to target MS and 53 to DS. Of the patients randomized to target MS, 50% achieved MS and 50% achieved DS. In the target DS group, 77% achieved DS and 23% achieved MS. The median total propofol dose (mg/kg) was lower in the MS group: MS 1.4 (95% confidence interval [CI] = 1.3-1.6, IQR = 1) versus DS 1.8 (95% CI = 1.6-2.0, IQR = 0.9). There were no differences in median OAAS during the procedure (MS 2.4 and DS 2.8), lowest OAAS (MS 2 and DS 2), percentage of images recalled (MS 4.7% vs. DS 3.8%, p = 0.73), or percentage of images recognized (MS 61.1% vs. DS 55%, p = 0.52). In the MS group, 41% patients had any AREs compared to 42% in the DS group (p = 0.77, 95% CI difference = -0.12 to 0.24). The total number of AREs was 23% lower in the MS group (p = 0.01, 95% CI = -0.41 to -0.04). There was no difference in patient-reported pain, satisfaction, or recollection VAS scores. Provider's rating of procedural difficulty and procedural success were similar in both groups. Targeting MS or DS did not reliably result in the intended sedation level. Targeting MS, however, resulted in a lower rate of total AREs and fewer patients had multiple AREs with no difference in procedural recall. As seen in previous reports, patients who achieved MS had less AREs than those who achieved DS. Our study suggests that a target of MS provides adequate amnesia with less need for supportive airway interventions than a target level of DS, despite the fact that it often does not result in intended sedation level.

Clinical characteristics and anesthesia management of intracranial space-occupying lesions during pregnancy: a retrospective analysis

Objective To analyze and summarize the clinical features and anesthesia management of patients with intracranial mass lesion during pregnancy. Methods We retrospectively collected 34 cases of intracranial mass lesions during pregnancy in our hospital from 2010 to 2017, and analyzed the characteristics, treatment, choice of anesthesia, and outcomes of the patients. Results A total of 34 cases of pregnant women suffered from intracranial mass lesions were enrolled in this study, and include 3 cases of pituitary adenoma, 2 cases of schwannoma, 5 cases of hemangioblastoma, 5 cases of hemangioma, 1 case of aneurysm, 1 case of dermoid cyst, 2 cases of meningioma, 1 case of neuroglial and neuronal mixed tumor, 12 cases of glioma, 1 case of medulloblastoma, and 1 case of choriocarcinoma. Regarding pregnant stages, 7 cases were in the early trimester, 13 cases in middle trimester, and 14 cases in late trimester of pregnancy. Twenty eight out of 34 cases were admitted into the hospital as emergency. As for the treatment, 9 cases received emergency neurosurgery, 3 cases received caesarean section and neurosurgery, 12 cases received emergency neurosurgery after caesarean section, 7 cases received conservative treatment, and 3 cases withdrew treatment after caesarean section. In neurosurgery treatment, 19 cases received brain mass lesion resection, 3 cases received hematoma clearance or decompression, 2 cases respectively received ventricular-peritoneal shunt and endovascular treatment. For obstetric management, 27 cases terminated pregnancy and 7 cases were expected to delivery. Twenty six out of 27 cases in the middle and late trimester of pregancy underwent caesarean section, and among them, 16 and 10 cases respectively received epidural and general anesthesia. The Observer′s Assessment of Alertness/Sedation(OAA/S) in patients received general anesthesia was lower than those received epidural anesthesia (P<0.05). MAP decreased more rapidly after delivery in patients under epidural anesthesia during surgery. There were 4 cases of maternal death and 2 cases of fetal death. Conclusions Intracranial mass lesion during pregnancy increased the risk of maternal and fetal death. The appropriate treatment requires comprehensive diagnosis involving obstetrician, anesthesiologists and neurosurgeons to fully evaluate patient′s intracranial tumor, gestational age and fetal maturity to timely terminate pregnancy and carry out appropriate neurosurgical treatment to ensure the safety of mother and fetus. Key words: Pregnancy; Intracranial mass lesion; Anesthesia; Neurosurgery

Postoperative patient-controlled analgesia with butorphanol in puerperants underwent cesarean section

Objective To compare the effect of postoperative patient-controlled intravenous analgesia(PCIA) with doses of butorphanol on puerperant after cesarean section. Methods Three hundred ASA Ⅰ or Ⅱ patients underwent cesarean section were randomly divided into 6 groups(n=50) respectively received tramadol 200.0 μg·kg-1·h-1(group T), butorphanol 3.0 μg·kg-1·h-1 (group B1), butorphanol 3.5 μg·kg-1·h-1(group B2), butorphanol 4.0 μg·kg-1·h-1(group B3), butorphanol 4.5 μg·kg-1·h-1(group B4), or butorphanol 5.0 μg·kg-1·h-1(group B5). The loading doses were 50 mg for tramadol in group T, and 0.5 mg for butorphanol in group B1-B5, and PCIA was initiated after operation. VAS and observer's assessment of alertness/sedation(OAA/S) scale were employed to assess the severity of rest pain, motion pain, and uterus systole pain before anesthesia(T0), 0(T1), 30 min(T2), 2 h(T3), 4 h(T4), 24 h(T5) and 48 h(T6) after the initiation of PCIA. The time to flatus, time to breastfeeding, time to lactation, side effects, and satisfaction scores were recorded. Results Compared with group T, VAS scores of rest pain, motion pain, and uterus systole pain at T5 in group B1 were higher(P 0.05). No differences were found in pain scores at T6 among 6 groups(P>0.05). Compared with group T, patients in group B1 need more PCIA bolus during T5-T6(P 0.05). Conclusions PCIA with butorphanol at a dose of 3.5 μg·kg-1·h-1 or 4.0 μg·kg-1·h-1 may provide optimal postoperative analgesia after cesarean section. Key words: Butorphanol; Cesarean section; Patient-controlled intravenous analgesia