Bis Groups Research Articles

Bispectral index monitoring: Optimizing anesthesia in rigid bronchoscopy.

This study investigates the application of bispectral index (BIS) monitoring in rigid bronchoscopy to enhance anesthetic delivery and patient outcomes, a topic that remains underexplored. A retrospective analysis of 155 patients undergoing elective rigid bronchoscopy under general anesthesia was conducted. Patients were divided into BIS-monitored and conventional anesthesia groups. Inclusion criteria were adults aged over 18 years with American Society of Anesthesiologists (ASA) physical status I-IV. No significant demographic differences were found between the groups. The BIS group showed significant reductions in propofol usage (231.40 ± 74.63 mg vs. 190.19 ± 91.83 mg, p= 0.003) and prednol dosage (94.27 ± 42.56 mg vs. 79.71 ± 18.97 mg, p= 0.020). Remifentanil administration approached statistical significance (56.99 ± 34.69 mcg vs. 45.36 ± 36.75 mcg, p= 0.055). No significant demographic differences were found between the groups. The BIS group showed significant reductions in propofol usage (231.40 ± 74.63 mg vs. 190.19 ± 91.83 mg, p= 0.003) and prednol dosage (94.27 ± 42.56 mg vs. 79.71 ± 18.97 mg, p= 0.020). Remifentanil administration approached statistical significance (56.99 ± 34.69 mcg vs. 45.36 ± 36.75 mcg, p= 0.055).

Reactive Dyes Bearing Bis(Monochlorotriazine) Group: Synthesis, Photophysical Properties and Realization of Salt‐Free Dyeing

AbstractA series of novel reactive dyes D1–D3 based on vinamidinium salt were designed and synthesized. Bis(monochlorotriazine) was introduced as the reactive group and sodium sulfonate was the water‐soluble group. Their photophysical properties were studied systematacially. The strong and sharp ground‐state absorption peak in the 250–320 nm range in the UV‐vis absorption spectrum of the aqueous solution could be attributed to the 1π–π* transition by the parent structure of the dyes, and the relatively broad absorption peak in the range of 300–650 nm could be attributed to the 1π–π* mixed intramolecular charge transfer. By applying this series of reactive dyes to the dyeing of four fabrics (silk, cotton, polyester/cotton blends, and polyester), the dyeing depths were in the range of 5.2–28.6 under salt‐free conditions. The results show that D3 with higher planarity can increase the dyeing depth. At length, fastening tests on dyed cotton fabrics and silk showed that this series of reactive dyes had a color fastness between grades 3 and 5 for abrasion and soap‐washing. In summary, these reactive dyes could be potential dyes for salt‐free dyeing applications.

In Situ Electrochemical Interfacial Polymerization for Covalent Organic Frameworks with Tunable Electrochromism.

A rapid in situ synthesis of electrochromic covalent organic frameworks (EC-COFs) was proposed by using green electrochemical interface polymerization of N,N,N',N'-tetrakis(4-aminophenyl)-1,4-benzenediamine (TPDA) and 2,5-dihydroxyterephthalaldehyde (DHBD). The synthetized TPDA-DHBD films exhibit stable polymorphic color variations under different applied potentials, which can be attributed to the redox state changes of bis(triphenylamine) and imine electroactive functional groups within the COFs skeleton. TPDA-DHBD represents markedly different electrochromisms from red to cyan due to the steric hindrance effect caused by the presence of UO2 2+, demonstrating the unique tunability of COFs materials. This work offers a new feasible idea for rapid EC-COFs synthesis and tunable EC-COFs realization.

In Situ Electrochemical Interfacial Polymerization for Covalent Organic Frameworks with Tunable Electrochromism

A rapid in situ synthesis of electrochromic covalent organic frameworks (EC‐COFs) was proposed by using green electrochemical interface polymerization of N,N,N’,N’‐tetrakis(p‐aminophenyl)p‐phenylenediamine (TPDA) and 2,5‐dihydroxy‐p‐phenylenedicarboxaldehyde (DHBD). The synthetized TPDA‐DHBD films exhibit stable polymorphic colour variations under different applied potentials, which can be attributed to the redox state changes of bis(triphenylamine) and imine electroactive functional groups within the COFs skeleton. TPDA‐DHBD represents markedly different electrochromisms from red to cyan due to the steric hindrance effect caused by the presence of UO22+, demonstrating the unique tunability of COFs materials. This work offers a new feasible idea for rapid EC‐COFs synthesis and tunable EC‐COFs realization.

Comparing Bispectral Index Monitoring vs Clinical Assessment for Deep Sedation in the ICU: Effects on Delirium Reduction and Sedative Drug Doses—A Randomized Trial

BackgroundSedative overdoses pose a delirium risk among Intensive Care Unit (ICU) patients, with potential mitigation through the use of a processed EEG monitor (BIS) to guide depth of sedation. Research QuestionCan BIS-guided deep sedation (RASS -4, -5) reduce sedative dosage and increase delirium-free and coma-free (DFCF) days? Study Design and MethodsA randomized controlled trial was conducted in a tertiary mixed ICU, enrolling patients requiring deep sedation for >8 hours. Patients were randomly assigned to either the Clinical Assessment (CA) or BIS groups (BIS range of 40-60). Both groups utilized a BIS sensor, while the CA group's screen remained covered. After deep sedation, BIS sensors were removed, and delirium was assessed twice daily by researchers blinded to the randomization. The primary outcome was the number of DFCF days within 14 days after deep sedation. Additionally, we compared doses of sedative drugs and BIS values during deep sedation. ResultsNinety-nine patients were included in the study. We found no significant difference in DFCF (p=0.1) between CA and BIS arms, but propofol doses were significantly lower in the BIS group (CA group 1.77 mg/kg/hr [95% CI 1.60, 1.93] vs. BIS group 1.44 mg/kg/hr [95% CI 1.04, 1.83]; p=0.03). During deep sedation, the CA group spent 46% of the total hours (95% CI 35, 57%) with BIS values below 40, whereas the BIS group spent 32% (95% CI 25, 40%), (p=0.03). Subgroup analysis focusing on patients sedated for more than 24 hours revealed an increase in DFCF in the BIS group (CA group median of 1 day [IQR 0, 9] vs. BIS group 8 days [IQR 0, 13]; p=0.04). InterpretationBIS-guided deep sedation did not improve DFCF days but reduced sedative drug use. In patients requiring sedation for more than 24 hours, it showed an improvement in DFCF days.

Effect of bispectral index on intra-operative awareness: A meta-analysis of randomized controlled studies.

Randomized controlled trials (RCTs) investigating the efficacy of bispectral index (BIS) to reduce intra-operative awareness (IOA) have reported conflicting results. The purpose of this meta-analysis is to consolidate results from RCTs to assess the efficacy of BIS in reducing IOA when compared to controls. Secondary outcomes included time to extubation, time to spontaneous and/or verbal eye opening, PACU discharge time, and utilization of inhaled anesthetics. RCTs which reported on one of the primary and/or secondary outcomes were included. Literature search utilized keywords "randomized control trial" and "intraoperative awareness." Meta-analysis was performed using RevMan 5. Twenty-seven RCTs were included in the study with a total of 35,585 patients, with 18,146 patients in the BIS and 17,439 in the control group. Eighteen of 14,062 patients (0.12%) and 42 of 16,765 (0.25%) reported definite IOA in the BIS and control group, respectively, with no statistically significant difference. BIS was effective in reducing the time to spontaneous eye opening by an average of 1.3 minutes and the time to extubation by an average of 1.97 minutes. There was no difference in PACU discharge times among the groups. There was a significant decrease in consumption of sevoflurane but no difference in desflurane and propofol compared to the control group. While BIS monitoring results in decreased incidence of intra-operative awareness by half, it was not statistically significant. BIS provides modest benefits with regard to reducing the time to extubation, the time to spontaneous eye opening, and consumption of sevoflurane.Level of evidence: I.

Bispectral index monitoring for sedation in scheduled adult colonoscopy: A randomized controlled trial

BackgroundPatients should be closely monitored during procedures under sedation outside the operating room, but it is unclear which type of monitoring is best. We investigated the efficacy and safety of BIS monitoring vs conventional monitoring for sedation during colonoscopy. MethodsWe performed a double-blind clinical trial in 180 patients undergoing elective colonoscopy. Patients were randomized to 1) the BIS group or 2) a control group, in which sedation was monitored with a BIS monitor or the Ramsay Sedation Score, respectively. The primary outcome was the rate of sedation-induced adverse events in both groups. Secondary outcomes were the characteristics of patients who developed adverse events, and time during colonoscopy when these events occurred, propofol and remifentanil dosage, and patient satisfaction. ResultsUnivariate analysis showed fewer cardiopulmonary complications in the BIS group (41.11% vs 57.78% in controls; p = 0.02). Multivariate analysis found a significantly higher risk of adverse events in older patients (95% CI, 1.013–1.091; p = 0.0087) and in men (95% CI, 1.129–7.668; p = 0.0272). These events were observed at the hepatic flexure. No significant differences between propofol or remifentanil dosage, use of rescue medication, and patient satisfaction were observed between groups. ConclusionsOur data suggest that BIS monitoring during sedation in scheduled colonoscopies reduces adverse respiratory events. Although its routine use in sedation does not appear to be warranted, clinicians should take steps to identify patients with a higher risk of complications who might benefit from this type of monitoring.

Monitorización del índice biespectral para sedación en colonoscopias electivas de pacientes adultos: ensayo controlado aleatorizado

BackgroundPatients should be closely monitored during procedures under sedation outside the operating room, but it is unclear which type of monitoring is best. We investigated the efficacy and safety of BIS monitoring vs conventional monitoring for sedation during colonoscopy. MethodsWe performed a double-blind clinical trial in 180 patients undergoing elective colonoscopy. Patients were randomized to 1)the BIS group or 2)a control group, in which sedation was monitored with a BIS monitor or the Ramsay Sedation Score, respectively. The primary outcome was the rate of sedation-induced adverse events in both groups. Secondary outcomes were the characteristics of patients who developed adverse events, and duration of colonoscopy when these events occurred, propofol and remifentanil dosage, and patient satisfaction. ResultsUnivariate analysis showed fewer cardiopulmonary complications in the BIS group (41.11% vs 57.78% in controls; P=.02). Multivariate analysis found a significantly higher risk of adverse events in older patients (95%CI: 1.013-1.091; P=.0087) and in men (95%CI: 1.129-7.668; P=.0272). These events were observed at the hepatic flexure. No significant differences between propofol or remifentanil dosage, use of rescue medication, and patient satisfaction were observed between groups. ConclusionsOur data suggest that BIS monitoring during sedation in scheduled colonoscopies reduces adverse respiratory events. Although its routine use in sedation does not appear to be warranted, clinicians should take steps to identify patients with a higher risk of complications who might benefit from this type of monitoring.

Comparison between Bispectral Index-guided Propofol Induction and Clinically-guided Induction in Adult Hypertensive Patients Undergoing Elective Laparoscopic Surgery: A Randomised Controlled Study

Introduction: Traditional clinical endpoints for propofol induction often led to unintentional overdose, leading to haemodynamic instability, delayed recovery, and other complications. Bispectral Index monitoring could potentially prevent undesired haemodynamic changes like hypotension. Aim: To compare BIS-guided propofol induction with clinically guided propofol induction. Materials and Methods: A randomised controlled study was conducted in the Department of Anaesthesiology at Apollo Hospitals, Guwahati, Assam, India, between December 7, 2020 and December 6, 2021, on adult hypertensive patients undergoing elective laparoscopic surgeries. The Clinical Group (n=30) received propofol induction based on clinical guidance, and the Bispectral index group (n=30) underwent Bispectral Index (BIS) guided induction. Demographic variables, the dose of drug required for BIS 50, and the total amount of drug consumed were recorded. After the administration of each dose, Systolic BP (SBP), Diastolic BP (DBP), Mean Arterial BP (MAP), Heart Rate (HR), and SpO2 were recorded. Frequencies and percentages were used to describe qualitative data, whereas the mean and standard deviation were used to express quantitative data. Parametric tests included unpaired t-tests for comparison between groups. A p-value of <0.05 was considered statistically significant. Results: Total 60 patients with 30 in each group, were studied. There was a steady fall in SBP, DBP, and MAP with successive incremental doses of 0.5 mg in both groups. Mean SBP was comparable between the two groups at dosages of 1 mg/ kg, 1.5 mg/kg, and 2 mg/kg. At 2.5 mg/kg, the clinical group had a significantly lower SBP (p=0.0001). Mean DBP was comparable in both groups at doses of 2 mg/kg and 2.5 mg/ kg but significantly lower in the BIS group at 1 mg/kg and at 1.5 mg/kg (p=0.003, p=0.01). Mean MAP was comparable at doses of 2 and 2.5 mg/kg but significantly lower in the BIS group at doses of 1 mg/kg and 1.5 mg/kg (p=0.007, p=0.02). Mean HR was comparable between the two groups at doses of 1 and 1.5 mg/kg. HR showed an increase in group CL and a gradual drop in group BIS with incremental doses. Mean HR was significantly lower in the group BIS at doses of 2 mg/kg and 2.5 mg/kg (p=0.001, p=0.001). The BIS group required a substantially lower total dose of propofol compared to the CL group (158.63±30.57 mg vs. 118.23±28.53 mg, p=0.0001). Conclusion: BIS-guided propofol induction leads to more stable haemodynamics during induction. It helps to titrate propofol administration, which, in turn, reduces the frequency of propofol overdose and its subsequent adverse effects on haemodynamic stability. The total dose of propofol consumed is also reduced.

Comparison between patient state index, bispectral index, and clinical parameters for propofol induction in Indian patients: A prospective study.

Patient state index (PSI) and bispectral index (BIS) are depth of anesthesia monitors utilized for the dosage of propofol usage for induction. We compare PSI, BIS, and Observer's Assessment of Alertness/Sedation Scale (OAA/S) for propofol dose usage for induction. Seventy-four ASA I and II patients, aged 18-65 years scheduled for laparoscopic cholecystectomy were included and divided into groups to titrate the drug dosage of propofol needed for induction of anesthesia, monitored by PSI (Group A), BIS (Group B), or clinical OAA/S (Group C). The drug dosage needed for induction was based on a PSI value of 25 ± 2, BIS value of 48 ± 2, and OAA/S value of ≤2 as the endpoint of induction in respective groups. Intraoperative hemodynamic variables and any complications were compared. The mean doses of propofol needed for induction were 2.23 mg/kg (Group A), 2.05 mg/kg (Group B), and 2.11 mg/kg (Group C). A significantly decreased dose was needed to achieve the desired end in Group B compared to Group A (P = 0.01). The hemodynamic variables such as heart rate, systolic blood pressure, and diastolic blood pressure among the three groups were comparable. The clinical method of titrating the dose of propofol for induction and anesthetic depth by the loss of verbal response is comparable to both BIS and PSI monitoring.

Effects of qCON and qNOX-guided general anaesthesia management on patient opioid use and prognosis: a study protocol

IntroductionThe adverse effects of general anaesthetic drugs (especially opioids) cannot be ignored. However, current nociceptive-monitoring techniques still lack consistency in guiding the use of opioids. This trial will study the...

Flexural strength, surface roughness, micro-CT analysis, and microbiological adhesion of a 3D-printed temporary crown material.

To evaluate the thermocycling effect of 3D-printed resins on flexural strength, surface roughness, microbiological adhesion, and porosity. 150 bars (8 × 2 × 2mm) and 100 blocks (8 × 8 × 2mm) were made and divided into 5 groups, according to two factors: "material" (AR: acrylic resin, CR: composite resin, BIS: bis-acryl resin, CAD: CAD/CAM resin, and PRINT: 3D-printed resin) and "aging" (non-aged and aged - TC). Half of them were subjected to thermocycling (10,000 cycles). The bars were subjected to mini-flexural strength (σ) test (1mm/min). All the blocks were subjected to roughness analysis (Ra/Rq/Rz). The non-aged blocks were subjected to porosity analysis (micro-CT; n = 5) and fungal adherence (n = 10). Data were statistically analyzed (one-way ANOVA, two-way ANOVA; Tukey's test, α = 0.05). For σ, "material" and "aging" factors were statistically significant (p < 0.0001). The BIS (118.23 ± 16.26A) presented a higher σ and the PRINT group (49.87 ± 7.55E) had the lowest mean σ. All groups showed a decrease in σ after TC, except for PRINT. The CRTC showed the lowest Weibull modulus. The AR showed higher roughness than BIS. Porosity revealed that the AR (1.369%) and BIS (6.339%) presented the highest porosity, and the CAD (0.002%) had the lowest porosity. Cell adhesion was significantly different between the CR (6.81) and CAD (6.37). Thermocycling reduced the flexural strength of most provisional materials, except for 3D-printed resin. However, it did not influence the surface roughness. The CR showed higher microbiological adherence than CAD group. The BIS group reached the highest porosity while the CAD group had the lowest values. 3D-printed resins are promising materials for clinical applications because they have good mechanical properties and low fungal adhesion.

Modulating Narrow-Band Phosphorescence of Pt2Au4 Cluster Complexes by Differently Positioned Bis(acetylide)-Naphthalene Linkers

To modulate phosphorescent characteristics of Pt2Au4 complexes with differently positioned bis(acetylide)naphthalene as a bridging ligand, four isomeric Pt2Au4 complexes (1–4) linked by 1,4-bis(acetylide)naphthalene (1), 1,5-bis(acetylide)naphthalene (2), 2,6-bis(acetylide)naphthalene (3), and 2,7-bis(acetylide)naphthalene (4) are elaborately designed and prepared. The Pt2Au4 complexes are strongly phosphorescent with the quantum yields as high as 52% in CH2Cl2 solutions, in strikingly contrast to weak phosphorescence of bis(acetylide)naphthalene-linked Pt2 precursors. After the formation of Pt2Au4 cluster structures, the increased molecular rigidity dramatically suppresses nonradiative relaxation, which becomes less competitive in contrast to the radiative relaxation of the emitting state, thus resulting in a remarkable enhancement of the quantum yields. Depending on the positions of bis(acetylide) groups attached to naphthalene rings, the phosphorescence of Pt2Au4 isomers in CH2Cl2 solutions follows 1 (640 nm) → 2 (582 nm) → 3 (567 nm) → 4 (529 nm) to show progressive blue shifts. As demonstrated by photophysical and theoretical studies, vibronic-structured narrow-band emission with a full width at half maxima (fwhm) of 707–1073 cm–1 is primarily ascribable to ligand-centered triplet states localized at bis(acetylide)naphthalenes, which is dramatically activated upon the formation of the Pt2Au4 cluster because the energy harvested by two PtAu2 cluster moieties is effectively transferred to bridging bis(acetylide)naphthalene. Taking advantage of Pt2Au4 complexes 1–4 as phosphorescent emitters, solution-processed OLEDs achieve narrow-band electroluminescence with peak external quantum efficiency of 11.0% for red-emitting complex 1 (fwhm = 45 nm or 1058 cm–1), 9.4% for orange-emitting complex 2 (fwhm = 33 nm or 960 cm–1), 13.7% for yellow-emitting complex 3 (fwhm = 33 nm or 1029 cm–1), and 15.2% for green-emitting complex 4 (fwhm = 24 nm or 848 cm–1).

Solvent-soluble thiophene-benzene based electrochromic polymers as electrode materials for supercapacitor

The bis(alkoxy) group para-substituted para-phenylene (p-phenylene) based conjugated polymers exhibit good electronic property due to the existence of intra-molecular non-covalent interaction between oxygen and heteroatom. However, the strong inter-molecular aggregation inhibits the ionic transport of polymer. Here, the strategy of changing side chain substitution position is employed to improve the properties of conjugated polymer. Three organic solvent-soluble conjugated polymers based on the bis(hexyloxy) group ortho-substituted p-phenylene were synthesized. The three polymers display small dihedral angles between thiophene and benzene. As the conjugated chain length of repeat units increasing, the redox potentials of polymers decrease gradually. From P1 to P2 to P3, their optical absorption regions red shift gradually, leading to neutral polymers display yellow for P1, orange for P2, magenta for P3, respectively. And the three polymers display good electrochromic properties (coloration efficiency: 641 cm2 C−1; response time: 0.2 s; optical contrast: 54%). Also, P2 possess the specific capacitance value of 170 F g−1, which is higher than that of most reported soluble conjugated polymers. Combining energy storage and electrochromic performance of the three polymers, their visualization monitor of energy storage were investigated.

Effect of bispectral index-guided total intravenous anesthesia in younger children: A prospective, randomized, controlled trial.

BIS-guided total intravenous anesthesia (TIVA) is widely used in children, but few studies have attempted to evaluation of the effect of BIS-guided TIVA in younger children. This study aimed to evaluate the effect of bispectral index (BIS) guidance during TIVA in younger children during anesthesia. This study is a prospective, randomized, single-blind and controlled clinical trial. This study enrolled pediatric patients (aged 1-3 years) who were scheduled for surgery under TIVA with propofol and remifentanil. The children were randomly assigned to the BIS group (group B) and standard clinical practice group (group S). The BIS values in group B were maintained at 45-60. The anesthesiologist controlled the depth of anesthesia in group S according to the variation in the clinical signs of the children. The time of extubation, duration of stay in post-anesthesia care unit (PACU), as well as BIS values, heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation at eight time points 1 min before induction (T1), 1 min after induction (1 min after the induction drugs were administrated) (T2), immediately after intubation (T3), immediately after skin incision (T4), 30 min after the start of the operation (T5), 60 min after the start of operation (T6), immediately after drug withdrawal (T7), and immediately after extubation (T8), propofol consumption, and postoperative adverse reactions were recorded. There was no significant difference in time to extubation 15(10,21) vs 14 (11,20) and duration of stay in PACU 27 (20,37) vs. 29 (22,39) between the group B and group S. At the time points 30 min after the start of the operation, 60 min after the start of operation and immediately after drug withdrawal, the BIS values in group S were significantly higher than those in group B (57 ± 9, 57 ± 9, 60 ± 8 vs 52 ± 7, 54 ± 7, 57 ± 6). The use of BIS-guided total intravenous anesthesia in younger children does not shorten the time of extubation and the duration of stay in the PACU. Chictr.org.cn identifier: 24/11/2017, ChiCTR-IOR-17013530.

Bispectral index: the current tool for monitoring unintended awareness and depth of anesthesia

BackgroundAwareness under general anesthesia is an unpleasant phenomenon that usually goes unnoticed and neglected. Numerous incidences of intraoperative awareness are not reported. Reasons for awareness might be the inadequate depth of anesthesia, less effective drugs, lack of proper anesthesia monitoring equipment, and untrained medical staff.The purpose of this study is to evaluate intraoperative awareness during general anesthesia and titrate the amount of anesthetic agents according to BIS values among patients and monitor hemodynamic parameters throughout the surgery.ResultsThe intraoperative awareness reported was 2% in the BIS group and 8% in the non-BIS group. The total propofol consumption in the BIS group was significantly less as compared to the non-BIS group (P value<0.0001).ConclusionsThe incidence of definite awareness with postoperative recall and propofol consumption was reduced in the BIS group as compared to the non-BIS group.

Effect of Bacillus coagulans SNZ 1969 on the Improvement of Bowel Movement in Loperamide-Treated SD Rats.

Bacillus coagulans SNZ 1969 (B. coagulans SNZ 1969) is a spore-forming bacterium reported to be effective in attenuating constipation. However, there is no study on whether B. coagulans SNZ 1969 could improve constipation through mucin secretion and changes in intestinal hormones. To address this knowledge gap, rats were orally administrated with various treatments for four weeks. The normal control (NOR) group received saline only. There were four constipation-induced groups. The LOP group received only loperamide (LOP), a constipation-inducing agent. The BIS group received both LOP and Bisacodyl (BIS, a constipation treatment agent). The SNZ-L group received both LOP and B. coagulans SNZ 1969 at 1 × 108 CFU/day. The SNZ-H group received LOP and B. coagulans SNZ 1969 at 1 × 1010 CFU/day. As indicators of constipation improvement, fecal pellet weight, fecal water content, gastrointestinal transit time, and intestinal motility were measured. Mucus secretion in the colon was determined by histological colon analysis and mucin-related gene expressions. Gastrointestinal (GI) hormones were also measured. SNZ-L and SNZ-H groups showed significantly increased fecal weights, fecal water contents, and intestinal motility than the LOP group. SNZ-L and SNZ-H groups also showed higher secretion of mucin in the colon and mRNA expression levels of Mucin 2 and Aquaporin 8 than the LOP group. The SNZ-H group showed significantly increased substance P but significantly decreased somatostatin and vasoactive intestinal peptide than the LOP group. The results of this study suggest that B. coagulans SNZ 1969 intake could attenuate constipation through mucin secretion and alteration of GI hormones.

Improved performance and stability of perovskite solar cells by iodine-immobilizing with small and flexible bis(amide) molecule

The iodine loss in the perovskite layer is currently-one of the major limit for further boosting power conversion efficiency (PCE) and long-term stability of perovskite solar cells (PSCs). Iodine-poor interface dominates the generation of some deep level defects and the phase collapse in the perovskite layer. So how to adequately immobilize the iodine and passivate the existing undercoordinated lead cations is a critical challenge. Herein, the interaction between the bifunctional amide group and the perovskite layer was systematically investigated. The Malonamide (MAM) with bis(amide) group in structure can selectively hold iodine in place or interact with undercoordinated lead cations through adjusting the molecular conformation, resulting in more ideal I/Pb ratio, highly suppressed ion migration, harmonized surface potential and reduced defect density. Eventually, a significantly improved efficiency of 24.13% was demonstrated with the MAM-treating devices, and the device kept 96% of its initial efficiency after 900 h under continuous illumination.

Neuromonitoring depth of anesthesia and its association with postoperative delirium

Delirium after surgery or Postoperative delirium (POD) is an underdiagnosed entity, despite its severity and high incidence. Patients with delirium require a longer hospital stay and present more postoperative complications, which also increases hospital costs. Given its importance and the lack of specific treatment, multifactorial preventive strategies are evidenced based. Our hypothesis is that using general anaesthesia and avoiding the maximum time in excessively deep anaesthetic planes through BIS neuromonitoring device will reduce the incidence of postoperative delirium in patients over the age of 65 and their hospitalization stay. Patients were randomly assigned to two groups: The visible BIS group and the hidden BIS neuromonitoring group. In the visible BIS group, the depth of anaesthesia was sustained between 40 and 60, while in the other group the depth of anaesthesia was guided by hemodynamic parameters and the Minimum Alveolar Concentration value. Patients were assessed three times a day by research staff fully trained during the 72 h after the surgery to determine the presence of POD, and there was follow-up at 30 days. Patients who developed delirium (n = 69) was significantly lower in the visible BIS group (n = 27; 39.1%) than in the hidden BIS group (n = 42, 60.9%; p = 0.043). There were no differences between the subtypes of delirium in the two groups. Patients in the hidden BIS group were kept for 26.6 ± 14.0 min in BIS values < 40 versus 11.6 ± 10.9 min (p < 0.001) for the patients in the visible BIS group. The hospital stay was lower in the visible BIS group 6.56 ± 6.14 days versus the 9.30 ± 7.11 days (p < 0.001) for the hidden BIS group, as well as mortality; hidden BIS 5.80% versus visible BIS 0% (p = 0.01). A BIS-guided depth of anaesthesia is associated with a lower incidence of delirium. Patients with intraoperative neuromonitoring stayed for a shorter time in excessively deep anaesthetic planes and presented a reduction in hospital stay and mortality.

Bispectral index-guided propofol sedation during endoscopic ultrasonography.

Background/AimsBispectral index (BIS) monitors process and display electroencephalographic data are used to assess the depth of anesthesia. This study retrospectively evaluated the usefulness of BIS monitoring during endoscopic ultrasonography (EUS). MethodsThis study included 725 consecutive patients who underwent EUS under sedation with propofol. BIS monitoring was used in 364 patients and was not used in 361. The following parameters were evaluated: (1) median dose of propofol; (2) respiratory and circulatory depression; (3) occurrence of body movements; (4) awakening score >8 at the time; and (5) awakening score 2 hours after leaving the endoscopy room. ResultsThe BIS group received a significantly lower median dose of propofol than the non-BIS group (159.2 mg vs. 167.5 mg; p=0.015) in all age groups. For patients aged ≥75 years, the reduction in heart rate was significantly lower in the BIS group than in the non-BIS group (1.2% vs. 9.1%; p=0.023). Moreover, the occurrence of body movements was markedly lower in the BIS group than in the non-BIS group (8.5% vs. 39.4%; p<0.001). ConclusionsDuring EUS examination, BIS monitoring is useful for maintaining a constant depth of anesthesia, especially in patients 75 years of age or older.