The mediating role of flow in the relationship between simulation design and simulation educational satisfaction in korean nursing students: a cross-sectional study

BACKGROUND

In Korea, there has been recent interest in nursing simulation education. In nursing, simulation education has many advantages, such as improving nursing students' problem-solving and judgment skills. Simulation education satisfaction is an indicator for evaluating educational performance from the learners' perspective and an important criterion for the development and progress of nursing education. Therefore, based on NLN/Jeffries simulation theory, this study aims to identify the relationship between simulation design and educational satisfaction and to confirm the mediating effect of flow.

METHODS

This cross-sectional study was conducted using 143 fourth-year nursing students who had participated in classes using simulations at three universities in Seoul, Daegu, and Jeonbuk. Data were collected from April 24 to May 3, 2023. Demographic data, simulation design scale (SDS), flow in simulation, and the educational satisfaction scale in simulation were collected via an online questionnaire. The collected data were analyzed through t-test, ANOVA, Scheffé test, and Pearson's correlation coefficient using SPSS 25.0. The mediating effect of flow was analyzed through the three-stage mediation effect procedure using hierarchical regression analysis and the Sobel test.

RESULTS

The simulation educational satisfaction had a statistically significant positive correlation with simulation design (r = .65, p < .001) and flow (r = .47, p < .001), and simulation design was positively correlated with the flow (r = .55, p < .001). The simulation design had a statistically significant effect on flow, which was the mediating variable (β = 0.55, p < .001). Additionally, simulation design had a statistically significant effect on simulation educational satisfaction (β = 0.56, p < .001). The significance of the mediating effect of flow on the relationship between simulation design and simulation educational satisfaction was investigated using the Sobel test, and the mediating effect of flow was found to be statistically significant (Z = 5.36, p < .001).

CONCLUSION

The significance of the current study lies in its confirmation of the link between simulation design and simulation educational satisfaction, as well as the mediating function of flow. Nursing students can achieve simulation educational satisfaction through simulation-based education if simulation educators follow best practices that improve flow through well-organized simulation design.

Electroencephalographic features of elderly patients during anesthesia induction with remimazolam: a sub-study of a randomized controlled trial

BACKGROUND

Although remimazolam is used as a general anesthetic in elderly patients due to its hemodynamic stability, the electroencephalogram (EEG) characteristics of remimazolam are not well-known. The purpose of this study was to identify the EEG features of remimazolam-induced unconsciousness in elderly patients and compare them with propofol.

METHODS

Remimazolam (n=26) or propofol (n=26) were randomly administered for anesthesia induction in surgical patients. The hypnotic agent was blinded only to the patients. During the induction of anesthesia, remimazolam was administered at a rate of 6 mg/kg/h, and propofol was administered at a target effect-site concentration of 3.5 μg/ml. The EEG signals from 8 channels (Fp1,Fp2,Fz,F3,F4,Pz,P3,P4, referenced to A2, using the 10-20 system) were acquired during the induction of anesthesia and in the postoperative care unit. Power spectrum analysis was performed, and directed functional connectivity between frontal and parietal regions was evaluated using normalized symbolic transfer entropy. Functional connectivity in unconscious processes induced by remimazolam or propofol was compared with baseline. To compare each power of frequency over time of the two hypnotic agents, a permutation test with t statistic was conducted.

RESULTS

Compared to the baseline in the alpha band, the feedback connectivity decreased by an average of 46% and 43%, respectively, after the loss of consciousness induced by remimazolam and propofol (95% CI for the mean difference:-0.073 to -0.044 for remimazolam, P<0.001,-0.068 to -0.042 for propofol,P<0.001). Asymmetry in the feedback and feedforward connectivity in the alpha band was suppressed after the loss of consciousness induced by remimazolam and propofol. There were no significant differences in the power of each frequency over time between the two hypnotic agents (minimum q-value=0.4235).

CONCLUSIONS

Both regimens showed a greater decrease in feedback connectivity compared to a decrease in feedforward connectivity after loss of consciousness, leading to a disruption of asymmetry between the frontoparietal connectivity.

Erythrobacter oryzae sp. nov., isolated from rice paddy soil

Two novel bacterial strains, designated as COR-2T and CR-8, were isolated from paddy soil. These isolates were aerobic, Gram-stain-negative, non-spore-forming, non-motile, rod-shaped, and formed orange-coloured colonies. Phylogenetic analysis based on 16S rRNA gene sequences showed that two strains formed a clear phylogenetic lineage with the genus Erythrobacter. Strains COR-2T and CR-8 showed 99.9 % 16S rRNA gene sequence similarity. Both strains had the highest 16S rRNA gene similarity of 99.1-99.7 % to Erythrobacter colymbi TPW-24T, Erythrobacter donghaensis SW-132T and Erythrobacter tepidarius DSM 10594T, respectively. The genome of strain COR-2T comprised 3 559 918 bp and the genomic DNA G + C content was 67.7 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain COR-2T and its closely related species of the genus Erythrobacter were 79.3-85.5% and 24.1-29.1 %, respectively. The major respiratory quinone was Q-10, while the major fatty acids were C18 : 1  ω7c and C17 : 1  ω6c. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, two unidentified phospholipids and eight unidentified lipids. Based on phylogenetic and phenotypic considerations, the two strains [COR-2T (type strain; = KACC 22941T=JCM 35529T) and CR-8 (= KACC 22945=JCM 35530)] are considered to represent novel species of the genus Erythrobacter, for which the name Erythrobacter oryzae sp. nov. is proposed.

A randomized, double-blind, single-dose, phase 1 study comparing the pharmacokinetics, pharmacodynamics, safety, and immunogenicity of denosumab biosimilar CT‑P41 and reference denosumab in healthy males

BACKGROUND

This study's objective was to demonstrate pharmacokinetic (PK) similarity and safety of denosumab biosimilar, CT‑P41, and United States-licensed reference denosumab (US-denosumab) in healthy male Asian adults, considering also pharmacodynamic (PD) outcomes.

RESEARCH DESIGN AND METHODS

This double-blind, two-arm, parallel-group, Phase 1 study randomized (1:1) healthy males to a single (60-mg) subcutaneous dose of CT‑P41 or US-denosumab. Primary endpoints were area under the concentration - time curve (AUC) from time zero to infinity (AUC0-inf), AUC from time zero to the last quantifiable concentration (AUC0-last), and maximum serum concentration (Cmax). PK equivalence was determined if 90% confidence intervals (CIs) for ratios of geometric least-squares means (gLSMs) were within the predefined 80-125% equivalence margin. Secondary PK, PD, safety, and immunogenicity outcomes were also evaluated.

RESULTS

Of 154 participants randomized (76 CT‑P41; 78 US-denosumab), 151 received study drug (74 CT‑P41; 77 US-denosumab). Primary and secondary PK results, PD results, safety, and immunogenicity were comparable between groups. Ninety percent CIs for ratios of gLSMs were within the predefined equivalence margin for AUC0-inf (100.4-114.7), AUC0-last (99.9-114.3), and Cmax (95.2-107.3).

CONCLUSIONS

Following a single dose in healthy males, CT‑P41 demonstrated PK equivalence with US-denosumab.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT06037395.

External validation of a pharmacokinetic model for target-controlled infusion of cefazolin as a prophylactic antibiotic

AIMS

This study aimed to evaluate the predictive performance of previously constructed cefazolin pharmacokinetic models and determine whether cefazolin administration via the target-controlled infusion (TCI) method may be possible in clinical practice.

METHODS

Twenty-five gastrectomy patients receiving cefazolin as a prophylactic antibiotic were enrolled. Two grams of cefazolin was dissolved in 50 mL of normal saline to give a concentration of 40 mg mL-1 . Before skin incision, cefazolin was administered using a TCI syringe pump, and its administration continued until the end of surgery. The target total plasma concentration was set to 100 μg mL-1 . Total and unbound plasma concentrations of cefazolin were measured in three arterial blood samples collected at 30, 60 and 120 min after the start of cefazolin administration. The predictive performance of the TCI system was evaluated using four measures: inaccuracy, divergence, bias and wobble.

RESULTS

Total (n = 75) and unbound (n = 75) plasma concentration measurements from 25 patients were included in the analysis. The pooled median (95% confidence interval) biases and inaccuracies were 6.3 (4.0-8.5) and 10.5 (8.6-12.4) for the total concentration model and -10.3 (-16.8 to -3.7) and 22.4 (18.2-26.7) for the unbound concentration model, respectively. All unbound concentrations were above 10 μg mL-1 .

CONCLUSION

Administration of cefazolin by the TCI method showed a clinically acceptable performance. Applying the TCI method by setting the total concentration as the target concentration rather than the unbound concentration is effective in maintaining a constant target concentration of cefazolin.

Search for Boosted Dark Matter in COSINE-100

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7  kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

Frequency and characteristics of patients with bispectral index values of 60 or higher during the induction and maintenance of general anesthesia with remimazolam

In Korea, the approved anesthetic regimen of remimazolam starts with 6 mg/kg/h or 12 mg/kg/h until loss of consciousness, followed by maintenance at 1-2 mg/kg/h. Some patients receiving remimazolam for general anesthesia experience occasional difficulty maintaining bispectral index (BIS) value ˂ 60. This retrospective study aimed to analyze the data from patients undergoing elective surgery under remimazolam based-general anesthesia to determine the frequency and physical characteristics of patients with BIS values ˂ 60. The criterion was established for patients with a poorly maintained BIS value < 60. The frequency and physical characteristics of patients who satisfied this criterion were investigated through their medical records. The modified Brice interview was conducted within 24 h after surgery. Among the 1500 patients included in the analysis, 61 (4.1%) met the criteria for BIS ˂ 60. Based on the modified Brice interview, none of the patients with poorly maintained BIS ˂ 60 complained of intraoperative awareness based on the modified Brice interview or exhibit specific physical characteristics. These patients accounted for less than 5% of the total population studied. Notably, physical characteristics alone are insufficient to predict such patients before surgery.

Detection efficiency calibration for an array of fourteen HPGe detectors

The CUP array of germanium (CAGe) is an array of fourteen high-purity germanium (HPGe) detectors. The detection efficiency of full-energy-peak emitted from the various samples assayed on the CAGe was calculated using the Monte Carlo simulation toolkit GEANT4. If the dead layer on the surface of the crystal is treated in the simulation as a continuous part of the active crystal, then the detection efficiency will be overestimated. Thus, the detection efficiency of the CAGe was adjusted using multi-nuclide source data and Monte Carlo simulations. The gamma spectra of the known activity source were obtained for each HPGe detector of the CAGe. The detection efficiency measured by the multi-source data was smaller than that of simulation data if the simulation treated the whole volume of germanium crystals as active for gamma detection. By optimizing the dead layers' thicknesses in the simulation, the detection efficiency calculated by the simulation could be matched to that of multi-source data.

Factors Influencing the Educational Needs and Nursing Intention Regarding COVID-19 Patient Care among Undergraduate Nursing Students

PURPOSE

This study examines final-year undergraduate nursing students to determine the educational needs for Coronavirus disease 2019 (COVID-19), knowledge of COVID-19, attitude toward COVID-19 patient care, and nursing intention toward COVID-19 patients.

METHODS

A structured questionnaire was used to collect data from 21 April to 6 May 2022. The participants included 144 final-year (4th year) undergraduate nursing students in Gangwon-do, Daegu-si, and Chungcheong-do. The SPSS/WIN 21.0 program was used to analyze the data; Pearson's correlation coefficients and multiple regression were further performed.

RESULTS

The attitude toward COVID-19 patient care (β = 0.38, p = 0.001), a cohabitant formerly infected with COVID-19, and the intention to study COVID-19 patient care (β = 0.16, p = 0.018) were found to influence nursing intention toward COVID-19 patients. These variables had a 27% explanatory power for nursing intention (F = 14.23, p < 0.001).

CONCLUSIONS

To foster undergraduate nursing students' nursing intention toward patients with emerging infectious diseases (EIDs), a program focused on cultivating a positive attitude toward EID patient care should be developed and implemented. The curriculum should further include education on EID patient care.

Multimorbidity adjusted years lost to disability rates calculated through Monte-Carlo simulation in Korea

OBJECTIVES

OBJECTIVES: To efficiently utilize limited health and medical resources, it is necessary to accurately measure the level of health, which requires estimating the multimorbidity-corrected burden of disease.

METHODS

METHODS: This study used 2015 and 2016 data from the National Health Insurance Service, and employed the list of diseases defined in a Korean study of the burden of disease, the criteria for prevalence, and the "cause-sequelae-health state" disease system. When calculating the years lost to disability (YLD), multimorbidity was corrected using Monte-Carlo simulation.

RESULTS

RESULTS: Correcting for multimorbidity changed YLD at all ages in Korea by -1.2% (95% confidence interval [CI], -24.1 to 3.6) in males and -12.4% (95% CI, -23.0 to 0.3) in females in 2015, and by -10.8% (95% CI, -24.1 to 4.6) in males and -11.1% (95% CI, -22.8 to 1.7) in females in 2016. The YLD rate for non-communicable diseases in males decreased more than that of other disease groups in both years, by -11.8% (95% CI, -19.5 to 3.6) and -11.5% (95% CI, -19.3 to -3.0), respectively. The overall YLD rate changed by -1.3% in the 5-year to 9-year age group, and the magnitude of this change remained similar until the 10-19-year age group, gradually decreased after 20 years of age, and steeply increased to more than 10% in those aged 60 and older.

RESULTS

CONCLUSIONS: Calculations of YLD should adjust for multimorbidity, as the disease burden can otherwise be overestimated for the elderly, who tend to exhibit a high prevalence of multimorbidity.

Predictive performance of pharmacokinetic models for target concentration-controlled infusion of cefoxitin as a prophylactic antibiotic in patients with colorectal surgery

We aimed to evaluate the predictive performance of previously constructed free (C_free) and total (C_total) cefoxitin pharmacokinetic models and the possibility of administering cefoxitin via the target‐controlled infusion (TCI) method in clinical practice. Two external validation studies (N = 31 for C_free model, N = 30 for C_total model) were conducted sequentially. Cefoxitin (2 g) was dissolved in 50 mL of normal saline to give a concentration of 40 mg mL⁻¹. Before skin incision, cefoxitin was infused with a TCI syringe pump. Target concentrations of free concentration and total concentration were set to 25 and 80 μg mL⁻¹, respectively, which were administered throughout the surgery. Three arterial blood samples were collected to measure the total and free plasma concentrations of cefoxitin at 30, 60 and 120 min, after the start of cefoxitin administration. The predictive performance was evaluated using four parameters: inaccuracy, divergence, bias and wobble. The pooled median (95% confidence interval) biases and inaccuracies were − 45.9 (−47.3 to −44.5) and 45.9 (44.5 to 47.3) for C_free model (Choi_F model), and − 16.6 (−18.4 to −14.8) and 18.5 (16.7 to 20.2) for C_total model (Choi_T_old model), respectively. The predictive performance of the newly constructed model (Choi_T_new model), developed by adding the total concentration data measured in the external validation, was better than that of the Choi_T_old model. Models constructed with total concentration data were suitable for clinical use. Administering cefoxitin using the TCI method in patients maintained the free concentration above the minimal inhibitory concentration (MIC) breakpoints of the major pathogens causing surgical site infection throughout the operation period.

Adjustment for Multimorbidity in Estimations of the Burden of Diseases Using Korean NHIS Data

The current multimorbidity correction method in the Global Burden of Disease studies assumes the independent occurrence of diseases. Those studies use Monte-Carlo simulations to adjust for the presence of multiple disease conditions for all diseases. The present study investigated whether the above-mentioned assumption is reasonable based on the prevalence confirmed from actual data. This study compared multimorbidity-adjusted years of lived with disability (YLD) obtained by Monte-Carlo simulations and multimorbidity-adjusted YLD using multimorbidity prevalence derived from National Health Insurance Service data. The 5 most common diseases by sex and age groups were selected as diseases of interest. No significant differences were found between YLD estimations made using actual data and Monte-Carlo simulations, even though assumptions about the independent occurrence of diseases should be carefully applied. The prevalence was not well reflected according to disease characteristics in those under the age of 30, among whom there was a difference in YLD between the 2 methods. Therefore, when calculating the burden of diseases for Koreans over the age of 30, it is possible to calculate the YLD with correction for multimorbidity through Monte-Carlo simulation, but care should be taken with under-30s. It is useful to apply the efficiency and suitability of calibration for multiplicative methods using Monte-Carlo simulations in research on the domestic disease burden, especially in adults in their 30s and older. Further research should be carried out on multimorbidity correction methodology according to the characteristics of multiple diseases by sex and age.

The contribution of form repetition to listeners' expectation of givenness in online reference resolution

Although it is clear that unaccented referring expressions are associated with given information in a discourse (Dahan et al., 2002), it is less clear what aspects of givenness are relevant. We examine whether listeners' expectation of givenness depends on repetition of a referring expression or on contextual evocation of a referent. The results from two visual world eye-tracking experiments suggest that for interpretation, listeners associated reduced prominence with a repeated referring expression. Listeners expect previously evoked referents to be candidates for reduced referring expressions only when they are referred to with the exact same referential form. The data also suggest that when referents are referred to with different referential forms across utterances, accenting facilitates linking those forms for co-reference.

Development of a new pharmacokinetic model for target-concentration controlled infusion of vancomycin in critically ill patients

The aim of this prospective study was to construct a new pharmacokinetic model of vancomycin for target-concentration controlled infusion (TCI). As the first loading dose, 25 mg/kg of vancomycin was administered during 60-90 min. Arterial blood samples were obtained at pre-set intervals to measure the serum concentrations of vancomycin. Population pharmacokinetic analysis was performed using the NONMEM software (ICON Development Solutions). In total, 197 serum concentration measurements from 22 patients were used to characterise the pharmacokinetics of vancomycin. A three-compartment mammillary model best described the pharmacokinetics of vancomycin in critically ill patients. The ideal body weight was a significant covariate for the central and slow peripheral volume of distribution. The weight and age converted to categorical variables at a cut-off of 65 years were a significant covariate for the clearance. Based on the results of stochastic simulation, the TCI method maintained the therapeutic concentration range for the longest duration. In addition, assuming that vancomycin was administered by the TCI method for 7 days, the dose was reduced by about 15% compared with the standard administration methods. The daily area under the curve values were maintained between 500 mg·h/L and 600 mg·h/L. TCI has the potential to become a new infusion method for patient-tailored dosing in critically ill patients. To administer vancomycin via TCI in clinical practice, the newly constructed pharmacokinetic model should undergo proper external validation.

Safety climate, nursing organizational culture and the intention to report medication errors: A cross-sectional study of hospital nurses

Background & Aim: Medication errors are the second most common accident after the fall accident in hospitals. Medication errors are a threat to patient safety. It is important to find the cause of such errors so that we can reduce them. However, the rate of medication error reporting is low. This study aimed to explore the factors associated with the intention to report medication errors among general hospital nurses. Methods & Materials: A cross-sectional study design was used. The participants were 171 registered nurses working in 4 general hospitals in South Korea. Convenient random sampling was used to select participants. Data were collected using mobile self-report structured questionnaires that covered general characteristics, medication errors and the intention to report them, the safety climate, and the nursing organizational culture. The data collection period was from March 14 to April 6, 2018. The data were analyzed by descriptive statistics, the Pearson correlation coefficients, and multiple regression analysis. Results: The mean scores of the intention to report medication errors and safety climate were 5.20±1.40 and 3.04±0.47, respectively. Each mean score of nursing organizational culture types was hierarch-oriented culture 3.63±0.51, relation-oriented culture 3.13±0.69, task-oriented-culture2.99±0.56, and innovation-oriented culture 2.85±0.67. Significant factors associated with the intention to report medication errors were the safety climate (β=.26, p=.001), a task-oriented culture (β=.16, p=.023), educational level (β=-.19, p=.006), the experience of medication errors (β=.19, p=.006), and male (β=-.18, p=.011). They accounted for 25% of the intention to report medication errors. Conclusion: This study found that the safety climate of the hospital, task-oriented culture of the nursing organization, education level, experience of medication errors, and gender associated with the intention to report medication errors. It is necessary to find ways to improve the safety climate of the hospital and the task-oriented culture of the nursing organization and establish a strategy for improving the intention to report medication errors for male nurses and nurses with medication errors.

Development of a new pharmacokinetic model for target-concentration controlled infusion of cefoxitin as a prophylactic antibiotic in colorectal surgical patients

AIMS

There are several limitations to the existing method of administering cefoxitin as a prophylactic antibiotic, and the limitations may be overcome by applying the target-concentration controlled infusion (TCI) method. Population pharmacokinetic parameters are required to administer cefoxitin by the TCI method. The aim of this study was to construct a new pharmacokinetic model of cefoxitin for the TCI method in colorectal surgical patients.

METHODS

In patients undergoing colorectal surgery, 2 g of cefoxitin was dissolved in 50 mL of saline and administered for 10 minutes prior to skin incision. Arterial blood samples were obtained at preset intervals to measure the total and free plasma concentrations of cefoxitin. Population pharmacokinetic analysis was performed using NONMEM software (ICON Development Solutions, Dublin, Ireland). Additionally, stochastic simulation was used to indirectly evaluate the effectiveness of the two administration methods (standard method vs TCI).

RESULTS

In total, 297 plasma concentration measurements from 31 patients were used to characterize the pharmacokinetics of cefoxitin. A three-compartment mammillary model described the pharmacokinetics of cefoxitin. Body weight and creatinine clearance were significant covariates for clearance. The stochastic simulation showed that when compared with the standard method, the TCI method has a significantly higher fraction of time that the free concentration of cefoxitin is maintained above the minimum inhibitory concentration (P < .001).

CONCLUSIONS

TCI has the potential to become a new infusion method for patient-tailored dosing in surgical patients. To administer cefoxitin via TCI in clinical practice, the newly constructed pharmacokinetic model should undergo proper external validation.

Performance of the Surgical Pleth Index and Analgesia Nociception Index in Healthy Volunteers and Parturients

Various commercially available nociception devices have been developed to quantify intraoperative pain. The Surgical Pleth Index (SPI) and Analgesia Nociception Index (ANI) are among the analgesic indices that have been widely used for the evaluation of surgical patients. This study aimed to evaluate the clinical performance of the SPI and ANI in conscious healthy volunteers and parturients. Ten healthy volunteers and 10 parturients participated in this study. An algometer was used to induce bone pain in the volunteers until they rated their pain as five on the numerical rating scale (NRS); this procedure was repeated during the administration of remifentanil or normal saline. The study comprised two periods, and the volunteers were infused with different solutions in each period: normal saline during one period and remifentanil during the other in a randomized order. The parturients’ SPI and ANI data were collected for 2 min when they rated their pain levels as 0, 5, and 7 on the NRS, respectively. Both the SPI and ANI values differed significantly between NRS 0 and NRS 5 (P < 0.001) in the volunteers, irrespective of the solution administered (remifentanil or normal saline). At NRS 5, the SPI showed similar values, irrespective of remifentanil administration, while the ANI showed significantly lower values on remifentanil administration (P = 0.028). The SPI and ANI values at NRS 5 and NRS 7 did not differ significantly in the parturients (P = 0.101 for SPI, P = 0.687 for ANI). Thus, the SPI and ANI were effective indices for detecting pain in healthy volunteers and parturients.

Population pharmacokinetic analysis of ropivacaine extended-release from a temperature-responsive hydrogel in rats

Therapeutic agents with a short half-life need to be administered frequently to achieve sustained and effective concentrations. This could be accomplished using sustained drug delivery technology. PF-72 (TGel Bio, Inc., Seoul, Korea) is a drug delivery system based on a powder obtained from lyophilisation of a reverse thermal hydrogel, which could assist in achieving prolonged pain relief if mixed with an anaesthetic and injected into the incision site following surgery. The pharmacokinetic parameters related to the absorption of the local anaesthetic ropivacaine delivered using this hydrogel were quantified. Ten rats were divided into two groups (n = 5 each), and equal doses (4 mg/kg) of different formulations were subcutaneously injected into the abdomen. The experimental group received PF-72 mixed with 0.75% ropivacaine, and the control group received 0.75% ropivacaine. Blood was collected at specific times to measure the plasma concentration of ropivacaine. Population pharmacokinetic analysis was performed using NONMEM VII level 4 (ICON Development Solutions, Dublin, Ireland). The one-compartment absorption model, which combines zero-order absorption and first-order absorption, was used to describe the change in ropivacaine plasma concentration over time. The type of formulation was a significant covariate for zero-order absorption duration (experimental group, 92.9 min; control group, 60.5 min). The addition of PF-72 to 0.75% ropivacaine increased the duration of absorption into the blood, suggesting a longer lasting effect of the analgesic injected into the surgical wound.

The relationship between leader-member exchange and intention to stay in Korean nurses: Focusing on the mediating role of compassion satisfaction

Background & Aim: Recently, there has been a growing interest in the nursing shortage. Although the number of nursing school has been increased and refreshment programs for inactive nurses have been run, the lack of nurses is still a common problem in Korea. Considering the importance of nurses' role in hospitals, it is important to investigate how to reduce turnover rates. This study aimed to investigate the mediating role of compassion satisfaction on the relationship between leader-member exchange (LMX) and intention to stay in Korea. Methods & Materials: A cross-sectional study design was used. Data were collected from 131 nurses from three university hospitals in South Korea. A demographic data form, LMX-7 scale, compassion satisfaction of the professional quality of life scale, and the nurses’ retention index were used to collect data. Results: Our results indicate that LMX has a positive effect on compassion satisfaction and intention to stay and compassion satisfaction has a positive effect on the intention to stay. In addition, compassion satisfaction was found to mediate the impact of LMX on the intention to stay. Conclusion: The present study is significant in that it confirms the relationship between LMX and intention to stay and the mediating role of compassion satisfaction. The nursing managers should pay attention to find ways to improve LMX and compassion satisfaction in hospitals in order to increase nurses’ intention to stay.

An allometric pharmacokinetic model and minimum effective analgesic concentration of fentanyl in patients undergoing major abdominal surgery

BACKGROUND

We aimed to characterise the population pharmacokinetics of fentanyl in adults and to determine the minimum effective concentration (MEC) and minimum effective analgesic concentration (MEAC) of i.v. fentanyl in patients after major abdominal open surgery.

METHODS

In the pharmacokinetic study, subjects received an intravenous bolus of fentanyl 100 μg during operation, and arterial blood was sampled at pre-set intervals. In addition, data from previously published fentanyl pharmacokinetic studies were incorporated to build a pharmacokinetic model. In the MEAC study, subjects were asked to rate their pain every 10 min using a VAS (0=no pain, 10=most severe pain) in the PACU. The first blood sample was obtained when wound pain was rated as ≥3 at rest or ≥5 during compression. Then, fentanyl 50 μg was administered every 10 min until the pain intensity had decreased to <3 at rest and <5 during compression, at which point the second blood was sampled and the first MEAC of fentanyl was measured. The same procedure was repeated to obtain a third sample (MEC) and a fourth sample (second MEAC).

RESULTS

In the population pharmacokinetic study (n=95), the plasma concentration of fentanyl over time was well-described by the three-compartment mammillary model using an allometric expression. The V1, V2, V3, Cl, Q1, and Q2 of a 70 kg subject were 10.1, 26.5, 206 L, 0.704, 2.38, and 1.49 L min^-1, respectively. In the MEAC study (n=30), the median (inter-quartile range) MEC and MEAC were 0.72 (0.58-1.05) ng ml^-1, and 0.99 (0.76-1.28) ng ml^-1, respectively.

CONCLUSION

These results provide a scientific basis for the use of fentanyl for acute postoperative pain management in surgical patients.

CLINICAL TRIAL REGISTRATION

KCT0003273 (http://cris.nih.go.kr).

A modified method of measuring plasma volume with indocyanine green: reducing the frequency of blood sampling while maintaining accuracy

Among various methods for measuring the plasma volume (PV), the indocyanine green (ICG) dilution technique is a relatively less invasive method. However, the ICG method is rather cumbersome because 10 blood samples need to be obtained within a short time after ICG administration. Thus, reducing the frequency of blood sampling while maintaining the accuracy would facilitate plasma volume measurement in clinical situations. We here developed a modified method to measure plasma volume using 2260 ICG plasma concentration data from 115 surgical patients. The mean relative error (MRE) and the percentage of cases with relative error (RE) greater than 5% in total (PRE) were used to quantify the difference between plasma volumes obtained by the original and modified methods. RE was determined as follows. RE(%) = (PV obtained by original method (PV_original)-PV obtained by modified method (PV_modified))/PV_original × 100. PV_modified was assumed to be equal to PV_original when the RE was < 5%. When the number of samples selected for the plasma volume estimation was 4 or less, the PRE was mostly 10% or more. Five out of the 10 blood samples (order: 1st, 2nd, 3rd, 9th, and 10th) showed similar accuracies with the plasma volume obtained by the original method (original: 2.72 ± 0.64 l, modified: 2.72 ± 0.65 l). This modified method may be able to aptly replace the original method and lead to a wider clinical application of the ICG dilution technique. Further validation is needed to determine if the results of this study may be applied in other populations.

Development and validation of the food involvement inventory (FII) featuring the attitudinal constructs

Food involvement is one of the personality traits that influences the food cognition and behavior of consumers. Given the irrelevance of previous food involvement scales such as measuring lifestyle diligence and a food culture, this study aimed to develop the food involvement inventory (FII) designed specifically for foods and current consumers. This study focused on identifying the factors/constructs of the FII that would best represent and explain food involvement through item generation, administration, and validation. The collected items from involvement-related scales and expert discussions were administrated based on the evidence of construct and content. Validation of the FII based on the exploratory factor analysis identified four attitudinal components as constructs (affective, cognitive, behavioral-purchase, and behavioral-cooking) within the final 25 items. These four constructs constituted structural models for the FII, and the models were shown to be acceptable in the confirmatory factor analysis.

PKconverter: R package to convert the pharmacokinetic parameters

Population pharmacokinetic analysis and modeling procedures typically require estimates of both population and individual pharmacokinetic parameters. However, only some of these parameters are contained in models and only parameters in the model can be estimated. In this paper, we introduce a new R package, PKconverter, to calculate pharmacokinetic parameters using the relationships among them. After fitting the model, other parameters can be calculated from the functional relationship among the parameters. PKconverter provides the functions to calculate whole parameters along with a Shiny application for converting the parameters. With this package, it is also possible to calculate the standard errors of the other parameters that are not in the model and estimate individual parameters simultaneously.

Quantitative analysis of the effect of fraction of inspired oxygen on peripheral oxygen saturation in healthy volunteers

Background

The international organization for standardization (ISO) 80601-2-61 dictates that the accuracy of a pulse oximeter should be assessed by a controlled desaturation study. We aimed to characterize the relationship between the fraction of inspired oxygen (FiO₂) and peripheral oxygen saturation (SpO₂) using a turnover model by retrospectively analyzing the data obtained from previous controlled desaturation studies.

Materials and Methods

Each volunteer was placed in a semi-Fowler's position and connected to a breathing circuit to administer the hypoxic gas mixture containing medical air, oxygen, nitrogen, and carbon dioxide. Volunteers were exposed to various levels of induced hypoxia over 70–100% arterial oxygen saturation (SaO₂). The study period consisted of two rounds of hypoxia and the volunteers were maintained in room air between each round. FiO₂ and SpO₂ were recorded continuously during the study period. A population pharmacodynamic analysis was performed with the NONMEM VII level 4 (ICON Development Solutions, Ellicott City, MD, USA).

Results

In total, 2899 SpO₂ data points obtained from 20 volunteers were used to determine the pharmacodynamic characteristics. The pharmacodynamic parameters were as follows: k_out = 0.942 1/min, I_max = 0.802, IC₅₀ = 85.3%, γ = 27.3.

Conclusion

The changes in SpO₂ due to decreases in FiO₂ well explained by the turnover model with inhibitory function as a sigmoidal model.

Effects of inspired oxygen concentration during emergence from general anaesthesia on postoperative lung impedance changes evaluated by electrical impedance tomography: a randomised controlled trial

We evaluated the effects of three different inspired oxygen concentrations (40%, 80%, and 100%) at anaesthesia emergence on postoperative lung volumes as measured by global impedance of electrical impedance tomography (EIT). This is a randomised, controlled, and assessor-blinded study in single-centre from May 2017 to August 2017. Seventy-one patients undergoing elective laparoscopic colorectal surgery with healthy lung condition were randomly allocated into the three groups based on the concentration of inspired oxygen applied during anaesthesia emergence: 40%-, 80%- or 100%-oxygen. End-expiratory lung impedance (EELI) with normal tidal ventilation and total lung impedance (TLI) with full respiratory effort were measured preoperatively and before discharge in the post-anaesthesia care unit by EIT, and perioperative changes (the ratio of difference between preoperative and postoperative value to preoperative value) were compared among the three groups. Postoperative lung impedances were significantly reduced compared with preoperative values in all patients (P < 0.001); however, perioperative lung impedance reduction (%) did not differ among the three oxygen groups. The mean reduction ratio in each 40%-, 80%-, and 100%-oxygen group were 37% ± 13%, 41% ± 14%, and 46% ± 14% for EELI (P = 0.125) and 40% ± 20%, 44% ± 17% and 49% ± 20% for TLI (P = 0.276), respectively. Inspired oxygen concentrations applied during anaesthesia emergence did not show a significant difference in postoperative lung volume as measured by EIT in patients undergoing laparoscopic colorectal surgery with healthy lungs.Trial registration cris.nih.go.kr (KCT0002642).

Mono-PEGylates of exenatide in branched and dimeric structures can improve in vivo stability and hypoglycemic bioactivity

Exenatide, a synthetic version of exendin-4, is a glucagon-like peptide-1 receptor agonist (GLP-1RA) used for treating diabetes, but its relatively short half-life is a major disadvantage. In this study, we attempted residue-specific mono-PEGylation to the middle of the amino acid backbone to extend its in vivo half-life. Exenatide was point-mutated from Lys to Cys at the 12th residue to yield a variant (K12C), and PEG-maleimide of varying molecular weights (MW) (5, 10, 20, 40 kD) was site-specifically conjugated to yield a mono-PEGylate with branched T-shape molecular structure. In another approach, we conjugated a bis-maleimide PEG (10 kD) to the middle of two K12Cs to yield an H-shape homodimer PEGylate In vitro bioactivity assays indicated that: (1) PEGylates conjugated with higher MW PEG lead to stronger receptor binding, (2) the branched form was superior to the linear configuration in the binding, and (3) both T-shape and H-shape mono-PEGylates demonstrated better potency than the native exenatide, evidenced by lower EC₅₀. Db/db mouse experiments to evaluate in vivo hypoglycemic activity indicated that: (1) all mono-PEGylates resulted in improved glucose tolerance compared to the native exenatide, (2) the homodimer PEGylate demonstrated much stronger hypoglycemic activity, especially during the initial period, and (3) the H-shape and T-shape mono-PEGylates (40 kD) maintained hypoglycemia for up to ca. 168 and 140 h, representing approximately 12- and 14-fold increase, respectively, compared with the native exenatide. Our findings suggest that the exenatide mono-PEGylates in unclassical molecular structures can improve in vivo pharmacokinetics properties.

The binary presence or absence of lymph node metastasis or extrathyroidal extension is not associated with survival in papillary thyroid cancers: Implications for staging systems

BACKGROUND

The characteristics of diagnosed papillary thyroid cancer (PTC) have changed over time with the increasing trend of early diagnosis, and the survival impact of conventional prognostic factors such as lymph node metastasis (LNM) and extrathyroidal extension (ETE) is controversial. We investigated PTC prognostic factors for overall survival (OS) and disease specific survival (DSS), focusing on LNM, ETE, and their implications for PTC staging systems.

METHODS

We assessed prognostic factors for OS and DSS in a nationwide sample of Korean PTC patients (N = 5192, median follow-up 121 months) using Cox regression. The binary presence or absence of LNM and ETE, as well as other measures of LNM and ETE, were examined for their survival impact. We also evaluated the relative performance of PTC staging systems before and after revising the staging criteria for LNM and ETE.

RESULTS

The binary presence of LNM or ETE was not a prognostic factor for OS or DSS, nor were other various measures of LNM. However, the extent of ETE as none, microscopic, or gross independently influenced survival (OS hazard ratio for gross vs. none: 3.28, 95% confidence interval (CI) 1.97-5.46; DSS hazard ratio for gross vs. none: 3.75, 95% CI 1.59-8.81). The performance of PTC staging systems improved when the extent of ETE and/or location of LNM were used as staging components.

CONCLUSION

The extent of ETE and/or location of LNM may be better survival indicators than their binary presence or absence, and we propose staging criteria revisions to pertinent staging systems to better reflect the contemporary PTC population.

Nano Hard Carbon Anodes for Sodium-Ion Batteries

A hindrance to the practical use of sodium-ion batteries is the lack of adequate anode materials. By utilizing the co-intercalation reaction, graphite, which is the most common anode material of lithium-ion batteries, was used for storing sodium ion. However, its performance, such as reversible capacity and coulombic efficiency, remains unsatisfactory for practical needs. Therefore, to overcome these drawbacks, a new carbon material was synthesized so that co-intercalation could occur efficiently. This carbon material has the same morphology as carbon black; that is, it has a wide pathway due to a turbostratic structure, and a short pathway due to small primary particles that allows the co-intercalation reaction to occur efficiently. Additionally, due to the numerous voids present in the inner amorphous structure, the sodium storage capacity was greatly increased. Furthermore, owing to the coarse co-intercalation reaction due to the surface pore structure, the formation of solid-electrolyte interphase was greatly suppressed and the first cycle coulombic efficiency reached 80%. This study shows that the carbon material alone can be used to design good electrode materials for sodium-ion batteries without the use of next-generation materials.

Predictive performance of a new pharmacokinetic model for propofol in underweight patients during target-controlled infusion

BACKGROUND

In a previous study, the modified Marsh and Schnider models respectively showed negatively- and positively-biased predictions in underweight patients. To overcome this drawback, we developed a new pharmacokinetic propofol model-the Choi model-for use in underweight patients. In the present study, we evaluated the predictive performance of the Choi model.

METHODS

Twenty underweight patients undergoing elective surgery received propofol via TCI using the Choi model. The target effect-site concentrations (Ces) of propofol were 2.5, 3, 3.5, 4, 4.5, and 2 μg/mL. Arterial blood samples were obtained at least 10 minutes after achieving pseudo-steady-state. Predicted propofol concentrations with the modified Marsh, Schnider, and Eleveld pharmacokinetic models were obtained by simulation (Asan pump, version 2.1.3; Bionet Co. Ltd., Seoul, Korea). The predictive performance of each model was assessed by calculation of four parameters: inaccuracy, divergence, bias, and wobble.

RESULTS

A total of 119 plasma samples were used to determine the predictive performance of the Choi model. Our evaluation showed that the pooled median (95% CI) bias and inaccuracy were 4.0 (-4.2 to 12.2) and 23.9 (17.6-30.3), respectively. The pooled biases and inaccuracies of the modified Marsh, Schnider, and Eleveld models were clinically acceptable. However, the modified Marsh and Eleveld models consistently produced negatively biased predictions in underweight patients. In particular, the Schnider model showed greater inaccuracy at a target Ce ≥ 3 µg/mL.

CONCLUSION

The new propofol pharmacokinetic model (the Choi model) developed for underweight patient showed adequate performance for clinical use.

Fine particulate matter and incidence of metabolic syndrome in non-CVD patients: A nationwide population-based cohort study

BACKGROUND

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

OBJECTIVE

To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5 μm (PM_2.5) and the risk of metabolic syndrome in Korean adults without CVD.

METHODS

Exposure to PM_2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM_2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.

RESULTS

Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m³ increase in PM_2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM_2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).

CONCLUSION

Exposure to one-year average PM_2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM_2.5 affects the onset of MS and its components which may lead to increase the risk of CVD.

Total thyroidectomy's association with survival in papillary thyroid cancers and the high proportion of total thyroidectomy in low-risk patients: Analysis of Korean nationwide data

BACKGROUND

Papillary thyroid cancer has an excellent prognosis, but the appropriate level of treatment is controversial. We compared survival between total thyroidectomy and less-than-total thyroidectomy, and examined the proportion of patients with papillary thyroid cancer in Korea undergoing total thyroidectomy.

METHODS

A nationwide sample of 5,230 papillary thyroid cancer patients was included (total thyroidectomy: 4,262, less-than-total thyroidectomy: 968). Using multivariate Cox regression, we compared overall survival and cause-specific survival by the extent of thyroidectomy (total thyroidectomy versus less-than-total thyroidectomy) for a 1:1 optimal match via the propensity score and for the total study population. We also compared overall survival by extent of thyroidectomy and the proportion of total thyroidectomy in different risk groups using papillary thyroid cancer staging systems.

RESULTS

We saw no difference in overall survival by extent of thyroidectomy in the propensity score matched population and the total study population (hazard ratio for less-than-total thyroidectomy 0.82, 95% confidence interval 0.52-1.29; hazard ratio for less-than-total thyroidectomy 1.03, 95% confidence interval 0.71-1.48, respectively). Similarly, there were no differences in thyroid cancer-specific survival by extent of thyroidectomy. None of the different risk groups showed differences in overall survival by surgical extent, although total thyroidectomy improved overall survival in older females with larger tumors. The proportion of papillary thyroid cancer patients who received a total thyroidectomy was 80% or greater regardless of risk group classification.

CONCLUSION

Total thyroidectomy had no survival advantage over less-than-total thyroidectomy in Korean papillary thyroid cancer patients except in a specific high-risk group. 80% or more of low-risk papillary thyroid cancer patients received a total thyroidectomy. These results suggest that further patient-centered treatment which considers both quality of life and clinical outcome is needed.

Individual differences in syntactic processing: Is there evidence for reader-text interactions?

There remains little consensus about whether there exist meaningful individual differences in syntactic processing and, if so, what explains them. We argue that this partially reflects the fact that few psycholinguistic studies of individual differences include multiple constructs, multiple measures per construct, or tests for reliable measures. Here, we replicated three major syntactic phenomena in the psycholinguistic literature: use of verb distributional statistics, difficulty of object-versus subject-extracted relative clauses, and resolution of relative clause attachment ambiguities. We examine whether any individual differences in these phenomena could be predicted by language experience or general cognitive abilities (phonological ability, verbal working memory capacity, inhibitory control, perceptual speed). We find correlations between individual differences and offline, but not online, syntactic phenomena. Condition effects on reading time were not consistent within individuals, limiting their ability to correlate with other measures. We suggest that this might explain controversy over individual differences in language processing.

Association of blood pressure components with mortality and cardiovascular events in prehypertensive individuals: a nationwide population-based cohort study

BACKGROUND

The effects of each blood pressure index [systolic and diastolic blood pressure (SBP, DBP), pulse pressure (PP), mean arterial pressure (MAP)] on the occurrence of mortality and cardiovascular (CV) events have not yet been investigated in prehypertensive populations.

METHODS

A total of 30,258 prehypertensive Korean participants underwent periodic health examination between 2003 and 2004 were enrolled, and the associations of BP components with mortality and CV events were investigated. Moreover, based on the DBP [80 ≤ DBP <90 mmHg (N = 21,323) and DBP <80 mmHg (N = 8,935)], the effects of BP components were also evaluated.

RESULTS

Multivariate Cox analyses in prehypertensive group revealed that the hazard ratios (HRs) were 1.121 and 1.130 per 10 mmHg increase in SBP and PP for mortality, respectively. Additionally, 10 mmHg increase of SBP (HR:1.090) was still significantly, but increase of PP (HR:1.060) was marginally associated with higher incidence of CV events. However, there were no significant associations with increase in DBP or MAP on adverse clinical outcomes in prehypertensive group. In the prehypertensive subjects with DBP <80 mmHg, CV events more frequently occurred by 38.8% and 28.5% per 10 mmHg increase in SBP and PP, respectively.

CONCLUSIONS

Prehypertensive subjects might need to be cautioned when they have high SBP or PP with low DBP even in healthy populations. Key message Prehypertensive subjects should be cautioned when they have high-systolic blood pressure or pulse pressure with low-diastolic blood pressure, even without previous hypertension, diabetes mellitus or chronic kidney disease.

Development and clinical application of an evidence-based pharmaceutical care service algorithm in acute coronary syndrome

WHAT IS KNOWN AND OBJECTIVE

Drug therapies are critical for preventing secondary complications in acute coronary syndrome (ACS). The purpose of this study was to develop and apply a pharmaceutical care service (PCS) algorithm for ACS and confirm that it is applicable through a prospective clinical trial.

METHODS

The ACS-PCS algorithm was developed according to extant evidence-based treatment and pharmaceutical care guidelines. Quality assurance was conducted through two methods: literature comparison and expert panel evaluation. The literature comparison was used to compare the content of the algorithm with the referenced guidelines. Expert evaluations were conducted by nine experts for 75 questionnaire items. A trial was conducted to confirm its effectiveness. Seventy-nine patients were assigned to either the pharmacist-included multidisciplinary team care (MTC) group or the usual care (UC) group. The endpoints of the trial were the prescription rate of two important drugs, readmission, emergency room (ER) visit and mortality.

RESULTS AND DISCUSSION

The main frame of the algorithm was structured with three tasks: medication reconciliation, medication optimization and transition of care. The contents and context of the algorithm were compliant with class I recommendations and the main service items from the evidence-based guidelines. Opinions from the expert panel were mostly positive. There were significant differences in beta-blocker prescription rates in the overall period (P = .013) and ER visits (four cases, 9.76%, P = .016) in the MTC group compared to the UC group, respectively.

WHAT IS NEW AND CONCLUSION

We developed a PCS algorithm for ACS based on the contents of evidence-based drug therapy and the core concept of pharmacist services.

The analgesic potency dose of remifentanil to minimize stress response induced by intubation and measurement uncertainty of Surgical Pleth Index

BACKGROUND

The aim of this study was to evaluate the analgesic potency dose of remifentanil to maintain Surgical Pleth Index (SPI) values at less than 50 after intubation in patients undergoing general anesthesia with target-controlled infusion of propofol and remifentanil.

METHODS

We randomly allocated 120 patients to receive one of three remifentanil target effect-site concentrations (5, 7, or 9 ng×mL-1) during intubation. The target effect-site concentrations of propofol were adjusted within a range of 2.5-3 μg×mL-1 to maintain bispectral index values at less than 60 during anesthesia induction. A reusable SPI sensor was placed on the index finger of the arm, and the SPI values were continuously recorded. The predicted probability for maintaining the SPI values at less than 50 after intubation against the cumulative amount of remifentanil was analyzed using logistic regression. The measurands were the baseline SPI value in patients without pain scheduled for surgery, and the maximal SPI value after intubation in patients receiving remifentanil with a target effect-site concentration of 7 ng×mL-1.

RESULTS

The estimated cumulative amount of remifentanil associated with a 50% and 95% probability of maintaining the SPI values at less than 50 after intubation were 135.0 µg and 330.4 µg, respectively. The estimated expanded uncertainty for the baseline and maximal SPI values after intubation in patients scheduled for surgery were 54.9±44.4 and 54.1±37.9, respectively, which corresponded to a confidence level of approximately 95%.

CONCLUSIONS

The analgesic potency dose of remifentanil to maintain SPI values at less than 50 after intubation was 135.0 µg.

Comparison of the analgesic effect of patient-controlled oxycodone and fentanyl for pain management in patients undergoing colorectal surgery

Oxycodone is a μ-opioid receptor agonist and is generally indicated for the relief of moderate to severe pain. The aim of this study was to compare the analgesic efficacy of patient-controlled oxycodone and fentanyl for postoperative pain in patients undergoing colorectal surgery. Patients scheduled to undergo elective colorectal surgery (n=82) were allocated to receive oxycodone (n=41, concentration of 1 mg/mL) or fentanyl (n=41, concentration of 15 μg/mL) for postoperative pain management. After the operation, pain using a numerical rating scale (NRS), delivery to demand ratio, infused dose of patient-controlled analgesia (PCA), side effects, and sedation levels were evaluated. Median (25%-75%) cumulative PCA dose of oxycodone group at 48 hours (66.9, 58.4-83.7 mL) was significantly less than that of fentanyl group (80.0, 63.4-103.3 mL, P=.037). Six hours after surgery, the mean (SD) NRS scores of the oxycodone and fentanyl groups were 6.2 (2.4) and 6.8 (1.9), respectively (P=.216). The mean equianalgesic potency ratio of oxycodone to fentanyl was 55:1. The groups did not differ in postoperative nausea, vomiting, and level of sedation. Patient-controlled oxycodone provides similar effects for pain relief compared to patient-controlled fentanyl in spite of less cumulative PCA dose. Based on these results, oxycodone can be a useful alternative to fentanyl for PCA in patients after colorectal surgery.

Blood Pressure Control During Chronic Kidney Disease Progression

BACKGROUND

Hypertension is a major cause of end-stage renal disease, and blood pressure (BP) control is crucial in patients with chronic kidney disease (CKD). However, it is generally inadequately controlled in CKD patients. We investigated the prevalence of CKD patients with inadequate BP control and its related factors, based on the CKD stage.

METHODS

We analyzed the health examination sample cohort database, which consisted of the randomly selected participants among all the citizens who received the health examination provided by National Health Insurance Service of Korea in 2012 and 2013.

RESULTS

There were 27,350 CKD patients (7.9%) out of a total of 345,044 participants. As CKD stage progressed, there were more patients with poorly controlled hypertension compared to those with well-controlled hypertension. In addition, systolic BP increased with CKD stage progression, while diastolic BP was not significantly different. Age, female, body mass index, increased pulse pressure, CKD stage, and levels of fasting glucose, total cholesterol, hemoglobin, and proteinuria were significant factors associated with poor control of BP in hypertensive CKD patients.

CONCLUSION

The proportion of CKD patients with poorly controlled hypertension significantly increased as CKD progressed, mainly associated with the increase in pulse pressure. However, future investigation for causal relationship between poorly controlled hypertension and its related factors is needed.

Development and Evaluation of a Korean Version of a Thyroid-Specific Quality-of-Life Questionnaire Scale in Thyroid Cancer Patients

Purpose

The purpose of this study was to develop a Korean version of the self-reported thyroid-specific quality of life (QoL) questionnaire for thyroid cancer patients (KT-QoL), and to evaluate its reliability and validity.

Materials and Methods

Two hundred seventy-two patients who underwent thyroidectomy from January to December 2010 were recruited in this study. The original version of the thyroid QoL was translated into Korean and evaluated for its reliability and validity. Using the developed KT-QoL, the postoperative QoL was evaluated until postoperative 1 year.

Results

At the preoperative baseline, the item internal consistency (IIC) ranged from ‒0.19 to 0.76, with low IIC values for items 2, 17, and 27. Item discriminant validity ranged from 86% to 97%. These values were similar at the postoperative periods. The internal consistency reliability (Cronbach’s α) was high for all dimensions, ranging from 0.90 to 0.95. The test-retest reliability (intraclass correlation coefficient) was acceptable (0.74-0.82). The external validity examined by the correlation between the item 1j (voice changes) of KT-QoL and the voice handicap index-30 ranged from 0.51 to 0.75. Patients’ QoL scores decreased after surgery, which demonstrated the sensitivity of the questionnaire. The QoL scores in patients with lobectomy showed best QoL scores postoperatively and those with receiving radioactive iodine still showed decreased QoL scores along the postoperative periods.

Conclusion

These results demonstrate that KT-QoL is a valid instrument for evaluating QoL of Korean patients with thyroid cancer.

A Novel Avian Paramyxovirus (Putative Serotype 15) Isolated from Wild Birds

In January 2014, a viral hemagglutinating agent named UPO216 was isolated from fecal droppings of wild birds at the UPO wetland in South Korea during an avian influenza surveillance program. Electron microscopy identified the UPO216 virus as an avian paramyxovirus (APMV). Pathogenicity tests and molecular pathotyping revealed that the virus was avirulent in chickens. The UPO216 virus was assigned to a serological group antigenically distinct from known serotypes of APMV (−1, −2, −3, −4, −6, −7, −8, and −9) by hemagglutination inhibition test, despite showing weak cross-reactivity with APMV-1 and APMV-9. The UPO216 virus RNA genome is 15,180 nucleotides (nts) in length, encodes 3′-N-P(V/W)-M-F-HN-L-5′ in that order, and shows unique genetic characteristics in terms of genomic composition and evolutionary divergence (0.43 or greater from known serotypes of APMV). Phylogenetic analysis revealed that the UPO216 occupies a branch separate from APMV-1, -9, -12, and -13. Serologic surveillance of wild birds (n = 880; 15 species, five Orders) detected UPO216-reactive antibodies in 4% (20/494) of serum samples taken from five species of wild duck belonging to the Order Anseriformes. In particular, UPO216-specific antibodies showing no cross-reaction with other serotypes of APMV were detected in four species: Eurasian teal (1/36), European wigeon (1/73), mallard (4/139), and Spot-Billed duck (1/137). These results indicate that the UPO216 virus has antigenically and genetically unique characteristics distinct from known serotypes of APMV and likely has been circulating widely in wild duck species of the Order Anseriformes. Thus, we propose the UPO216 isolate as a prototype strain of a novel APMV serotype (putative APMV-15).

An upper limit of Cr-doping level to Retain Zero-strain Characteristics of Li4Ti5O12 Anode Material for Li-ion Batteries

Since Li₄Ti₅O₁₂ as a promising anode material in lithium-ion batteries (LIBs) has a poor rate performance due to low electronic conductivity, a doping of Li₄Ti₅O₁₂ with heterogeneous atoms has been considered to overcome this problem. Herein, we report that there is an upper limit of doping level to maintain the zero strain characteristics of Li₄Ti₅O₁₂ lattice during charge/discharge process. By using synchrotron studies, it was revealed that the Li⁺ diffusivity was maximized at a certain doping level for which the conductivity was markedly increased with maintaining the zero strain characteristics. However, with more doses of dopants over the upper limit, the lattice shrank and therefore the Li⁺ diffusivity decreased, although the electronic conductivity was further increased in comparison with the optimal doping level.

Abstract P4-15-01: Cost-effectiveness of pre-implantation genetic diagnosis for BRCA mutation carriers

Introduction: Management of BRCA mutation carriers is very expensive due to preventive surgeries and/or screening tests, as well as greater likelihood of cancer treatment. The related cancer burden and costs continue from generation to generation. One relatively new option for male or female BRCA mutation carriers, who wish to have children, is pre-implantation genetic diagnosis (PGD) of in vitro fertilized embryos. PGD eliminates the mutation from the descendants of these carriers. The purpose of this study was to model the cost-effectiveness of PGD.

Methods: We developed a Markov Model using TreeAge Pro 2016 and compared incidence of cancers, cancers-related death, costs, quality adjusted life-years (QALY), and incremental cost-effectiveness ratio (ICER) in the 2nd generation associated with conventional management of BRCA mutation carriers vs. PGD using a U.S. third-party payer's perspective with a lifetime horizon at a discount rate of 3% per year. In the model, health states were implemented to reflect the natural history of breast and ovarian cancer for women, and prostate cancer (and breast cancer in BRCA2 mutation carriers) for men. Model data were obtained from published literature. Costs were determined from published data and insurance payment schedules.

Results: Our preliminary results show that for BRCA1 mutation carriers, the PGD with IVF strategy is associated with an increase of 0.29 QALYs and costs an additional $292.68 per person, translating to an ICER of $1,014.25/QALY when compared with “No PGD”, making it highly cost-effective. For BRCA2 mutation carriers, the PGD with IVF strategy is associated with an increase of 0.17 QALYs and costs an additional $4,916.88 per person, translating to an ICER of $28,436.10/QALY when compared with “No PGD”, making it cost-effective.

Table 1StrategyCost ($)Incr Cost ($)Eff (QALY)Incr Eff (QALY)Incr C/E ($/QALY) BRCA 1     No PGD323,347.22 28.41  PGD323,639.89292.6828.70.291,014.25BRCA 2     No PGD318,723.02 28.52  PGD323,639.894,916.8828.70.1728,436.10

Conclusion: PGD for both BRCA1 and BRCA2 mutation carriers reduces cancer burden, increases QALYs and, is very cost-effective in the 2nd generation cohort, making this an attractive option from the perspectives of patients and public payers. Our estimates are conservative because the cost-effectiveness of PGD will likely improve further if subsequent generations are included in the model, given the expected further reduction in cancer burden and associated cost-savings in subsequent generations.

Citation Format: Lipton JH, Wong WWL, Warner E, Greenblatt EM, Lee EK, Chan KKW. Cost-effectiveness of pre-implantation genetic diagnosis for BRCA mutation carriers [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-15-01.

Safety and Efficacy of a Membrane-Tube-Type Glaucoma Shunt Device: An Animal Trial

PURPOSE

To evaluate the safety and efficacy of a membrane-tube-type glaucoma shunt device (MT-device), which was developed to control intraocular pressure (IOP) with a lower chance of complications than conventional glaucoma surgery, in a rabbit model.

MATERIALS AND METHODS

The MT-device consists of an expanded polytetrafluoroethylene membrane (thickness 0.2 mm, area 2.5 × 2.5 mm²) and a tube (internal diameter 76 µm, external diameter 175.5 µm, length 7 mm) attached to the membrane. The device was implanted into the left eyes of nine New Zealand white rabbits. The tube was placed in the anterior chamber through paracentesis, and the membrane was fixated on the scleral surface; this induces aqueous drainage from the anterior chamber to the subconjunctival space. IOP, filtering bleb morphology, depth and inflammation of the anterior chamber, and possible complications were evaluated periodically for 8 weeks after surgery. Histological sections were analyzed at 2 and 8 weeks after the surgery.

RESULTS

Mean IOP decreased from a preoperative value of 8.7 ± 1.2-4.7 ± 0.6 mmHg at postoperative 8 weeks (p < 0.05). The filtering bleb was maintained during the study period. There were no major postoperative complications. Histologic assessment revealed that 2 weeks after the surgery, fibrous encapsulation, inflammatory cells, and fibroblasts were observed around the MT-device; however, 8 weeks after the surgery, minimal inflammation was observed.

CONCLUSIONS

The MT-device showed good biocompatibility and effective IOP reduction with a low risk of complications in a rabbit model.