Tag: statistics

AANA J. 2022 Aug;90(4):303-309.

ABSTRACT

The purpose of this study was to evaluate certified registered nurse anesthetist (CRNA) current pediatric atropine dosing practices. Emphasis was placed on rationale for dosing and knowledge regarding current literature and guidelines. An electronic survey was deployed by the American Association of Nurse Anesthetists (AANA)’s survey department to a total of 2,905 CRNAs who are current AANA members. The survey was completed by 98 CRNAs, of which 67 selected that they do not administer anesthesia to pediatric patients weighing less than 5 kg and were excluded from further survey participation. The responses from the remaining 31 CRNAs were utilized for data analysis (n = 31). Approximately two thirds of participants (64.5%) were unaware of available guidelines pertaining to pediatric dosing of atropine within the last 5 years. A statistically significant difference existed when analyzing whether awareness of guidelines was associated with knowledge of the correct American Heart Association recommended pediatric atropine dose. Providers who were aware of guidelines reported the correct dose 100% of the time, whereas those unaware of guidelines reported the correct dose only 65% of the time (P = .03). Variability in clinical practices and sources guiding practice should be addressed to avoid potential overdosing in the vulnerable neonatal population.

PMID:35943758

AANA J. 2022 Aug;90(4):288-292.

ABSTRACT

Student registered nurse anesthetists (SRNAs) are required by the Council on Accreditation to provide anesthetics to a minimum of 30 patients ages 2-12 years and 10 patients younger than 2 years. Pediatric anesthesia can prove to be stressful because children are at higher risk for morbidity and mortality during the perioperative period compared with adults. Simulation allows SRNAs the opportunity to review and develop skills in a safe and supportive environment. The purpose of this project was to provide a high-fidelity pediatric simulation for SRNAs prior to their pediatric rotation to improve skills, knowledge, and self-confidence in the recognition and management/treatment of common pediatric anesthesia complications (airway obstruction, laryngospasm, bronchospasm, and bradycardia). Twenty SRNAs enrolled in a nurse anesthesia program participated in the pediatric anesthesia simulation prior to the start of their pediatric anesthesia rotation. Participants completed surveys at three intervals; presimulation, postsimulation, and at the end of their pediatric rotation that addressed the trainee’s perceived self-confidence level and ability to identify and manage/treat common pediatric anesthesia complications. Statistical significance (P < .05) was achieved in the participants overall self-confidence levels in their ability to recognize, treat, and manage common pediatric complications (P = .00) after completion of simulation experience.

PMID:35943755

AANA J. 2022 Aug;90(4):263-270.

ABSTRACT

The effectiveness of propofol infusion on postoperative nausea and vomiting (PONV) is poorly understood in relation to various patient and procedure characteristics. This retrospective cohort study aimed to quantify the effectiveness of propofol infusion when administered either via total intravenous administration (TIVA) or combined intravenous anesthesia (CIVA) with inhalational agents on PONV. The relationship between propofol infusion and PONV was characterized controlling for patient demographics, procedure characteristics, PONV risk factors, and antiemetic drugs in adult patients (age ≥18 years) undergoing general anesthesia. Learned coefficients from multivariate regression models were reported as “lift” which represents the percentage change in the base likelihood of observing PONV if a variable is present versus absent. In a total of 41,490 patients, models showed that propofol infusion has a naive effect on PONV with a lift of -41% (P < .001) when using TIVA and -17% (P < .001) when using CIVA. Adding interaction terms to the model resulted in the loss of statistical significance in these relationships (lift of -30%, P = .23, when using TIVA, and -42%, P = .36, when using CIVA). It was further found that CIVA/TIVA are ineffective in short cases (CIVA * short surgery duration: lift = 49%, P < .001 and TIVA * short surgery duration: lift = 56%, P < .001).

PMID:35943751

J Chem Inf Model. 2022 Aug 9. doi: 10.1021/acs.jcim.2c00144. Online ahead of print.

ABSTRACT

A fast and accurate operational model of electron density is crucial in many scientific disciplines including crystallography, molecular biology, pharmaceutical, and structural chemistry. In quantum crystallography, the aspherical refinement of crystal structures is becoming increasingly popular because of its accurate description in terms of physically meaningful properties. The transferable aspherical atom model (TAAM) is quick and precise, though it requires a robust algorithm for atom typing and coverage of the most popular atom types present in small organic molecules. Thus, the University at Buffalo Databank (UBDB) has been renamed to the Multipolar Atom Types from Theory and Statistical clustering (MATTS) data bank, broadened, restructured, and implemented into the software DiSCaMB with 651 atom types obtained from 2316 small-molecule crystal structures containing C, H, N, O, P, S, F, Cl, and Br atoms. MATTS2021 data bank now covers most of the small molecules, peptides, RNA, DNA, and some frequently occurring cations and anions in biological, pharmaceutical, and organic materials, including the majority of known crystal structures composed of the above elements. The multipole model parameters (P_val, κ, κ’, P_lm) obtained for different atom types were greatly influenced by neighboring atom types, hybridization, geometrical strain in the ring system, and charges on the molecule. Contrary to previous findings, the atoms showing variable oxidation states and ions deviate from the linear dependence of monopole-derived charges on the expansion-contraction κ parameter.

PMID:35943747 | DOI:10.1021/acs.jcim.2c00144

J Chem Inf Model. 2022 Aug 9. doi: 10.1021/acs.jcim.2c00145. Online ahead of print.

ABSTRACT

The multipole model (MM) uses an aspherical approach to describe electron density and can be used to interpret data from X-ray diffraction in a more accurate manner than using the spherical approximation. The MATTS (multipolar atom types from theory and statistical clustering) data bank gathers MM parameters specific for atom types in proteins, nucleic acids, and organic molecules. However, it was not fully understood how the electron density of particular atoms responds to their surroundings and which factors describe the electron density in molecules within the MM. In this work, by applying clustering using descriptors available in the MATTS data bank, that is, topology and multipole parameters, we found the topology features with the biggest impact on the multipole parameters: the element of the central atom, the number of first neighbors, and planarity of the group. The similarities in the spatial distribution of electron density between and within atom type classes revealed distinct and unique atom types. The quality of existing types can be improved by adding better parametrization, definitions, and local coordinate systems. Future development of the MATTS data bank should lead to a wider range of atom types necessary to construct the electron density of any molecule.

PMID:35943739 | DOI:10.1021/acs.jcim.2c00145

Evol Comput. 2022 Aug 9:1-21. doi: 10.1162/evco_a_00314. Online ahead of print.

ABSTRACT

In the traffic light scheduling problem the evaluation of candidate solutions requires the simulation of a process under various (traffic) scenarios. Thus, good solutions should not only achieve good objective function values, but they must be robust (low variance) across all different scenarios. Previous work has shown that combining IRACE with evolutionary operators is effective for this task due to the power of evolutionary operators in numerical optimization. In this paper, we further explore the hybridization of evolutionary operators and the elitist iterated racing of IRACE for the simulation-optimization of traffic light programs. We review previous works from the literature to find the evolutionary operators performing the best when facing this problem to propose new hybrid algorithms. We evaluate our approach over a realistic case study derived from the traffic network of Málaga (Spain) with 275 traffic lights that should be scheduled optimally. The experimental analysis reveals that the hybrid algorithm comprising IRACE plus differential evolution offers statistically better results than the other algorithms when the budget of simulations is low. In contrast, IRACE performs better than the hybrids for high simulations budget, although the optimization time is much longer.

PMID:35943729 | DOI:10.1162/evco_a_00314

Am J Physiol Lung Cell Mol Physiol. 2022 Aug 9. doi: 10.1152/ajplung.00126.2022. Online ahead of print.

ABSTRACT

^99mTc-hexamethylpropyleneamine oxime (HMPAO) and ^99mTc-duramycin in vivo imaging detects pulmonary oxidative stress and cell death, respectively, in rats exposed to >95% O₂ (hyperoxia) as a model of Acute Respiratory Distress Syndrome (ARDS). Pre-exposure to hyperoxia for 48 h followed by 24 h in room air (H-T) is protective against hyperoxia-induced lung injury. This study’s objective was to determine the ability of ^99mTc-HMPAO and ^99mTc-duramycin to track this protection and to elucidate underlying mechanisms. Rats were exposed to normoxia, hyperoxia for 60 h, H-T, or H-T followed by 60 h of hyperoxia (H-T+60). Imaging was performed 20 minutes post intravenous injection of either ^99mTc-HMPAO or ^99mTc-duramycin. ^99mTc-HMPAO and ^99mTc-duramycin lung uptake was 200% and 167% greater (p <0.01) in hyperoxia compared to normoxia rats, respectively. On the other hand, uptake of ^99mTc-HMPAO in H-T+60 was 24% greater (p <0.01) than in H-T rats, but ^99mTc-duramycin uptake was not significantly different (p=0.09). Lung wet-to-dry weight ratio, pleural effusion, endothelial filtration coefficient, and histological indices all showed evidence of protection and paralleled imaging results. Additional results indicate higher mitochondrial complex IV activity in H-T versus normoxia rats, suggesting that mitochondria of H-T lungs may be more tolerant of oxidative stress. A pattern of increasing lung uptake of ^99mTc-HMPAO and ^99mTc-duramycin correlates with advancing oxidative stress and cell death and worsening injury, whereas stable or decreasing ^99mTc-HMPAO and stable ^99mTc-duramycin reflects hyperoxia tolerance, suggesting the potential utility of molecular imaging for identifying at-risk hosts that are more or less susceptible to progressing to ARDS.

PMID:35943727 | DOI:10.1152/ajplung.00126.2022

J Endocrinol Invest. 2022 Aug 9. doi: 10.1007/s40618-022-01885-5. Online ahead of print.

ABSTRACT

PURPOSE: To investigate the association of cytochrome P450 2E1 (CYP2E1) C-1054T (rs2031920) and 96-bp I/D genetic variations with the risk of polycystic ovary syndrome (PCOS), and to estimate the effects of genotypes on the clinical, metabolic, hormonal, and oxidative stress indicators.

METHODS: This case-control study included 762 control women and 1034 patients with PCOS. Genotypes were determined using polymerase chain reaction and/or restriction fragment length polymorphism analysis. Clinical and biochemical parameters were also analyzed.

RESULTS: Frequencies of the TT + CT genotype (35.4 vs. 28.9%) and T allele (19.6 vs. 16.0%) of the CYP2E1 C-1054T polymorphism were significantly higher in the PCOS group than in the control group (OR = 1.350, 95% CI 1.103-1.652, P = 0.004 for the dominant model). Genotype TT + CT remained a significant predictor of PCOS in a logistic regression model including age, body mass index (BMI), and recruitment year of participants (OR = 1.345, 95% CI 1.071-1.688, P = 0.011). No statistical differences were found in the genotype and allele frequencies of CYP2E1 96-bp I/D polymorphism. However, the combined genotype DD/TT + CT was related to an increased risk of PCOS when the DD/CC wild-type combined genotype was used as a reference. Patients with the I allele of 96-bp I/D polymorphism had a lower BMI but higher plasma apolipoprotein B and oxidized low-density lipoprotein cholesterol levels than those with the DD genotype.

CONCLUSION: CYP2E1 C-1054T, but not 96-bp I/D, genetic polymorphism is associated with an increased risk of PCOS in Chinese women.

PMID:35943720 | DOI:10.1007/s40618-022-01885-5

Transpl Infect Dis. 2022 Aug 9:e13920. doi: 10.1111/tid.13920. Online ahead of print.

ABSTRACT

BACKGROUND: Carbapenem-resistant Enterobacterales (CRE) colonisation at liver transplantation (LT) increases the risk of CRE infection after LT, which impacts on recipients’ survival. Colonization status usually becomes evident only near LT. Thus, predictive models can be useful to guide antibiotic prophylaxis in endemic centres.

AIMS: This study aimed to identify risk factors for CRE colonisation at LT in order to build a predictive model.

METHODS: Retrospective multicentre study including consecutive adult patients who underwent LT, from 2010 to 2019, at two large teaching hospitals. We excluded patients who had CRE infections within 90 days before LT. CRE screening was performed in all patients on the day of LT. Exposure variables were considered within 90 days before LT and included cirrhosis complications, underlying disease, time on the waiting list, MELD and CLIF-SOFA scores, antibiotic use, intensive care unit and hospital stay, and infections. A machine learning model was trained to detect the probability of a patient being colonized with CRE at LT.

RESULTS: A total of 1544 patients were analyzed, 116 (7.5%) patients were colonized by CRE at LT. The median time from CRE isolation to LT was 5 days. Use of antibiotics, hepato-renal syndrome, worst CLIF sofa score, and use of beta-lactam/beta-lactamase inhibitor increased the probability of a patient having pre-LT CRE. The proposed algorithm had a sensitivity of 66% and a specificity of 83% with a negative predictive value of 97%.

CONCLUSIONS: We created a model able to predict CRE colonization at LT based on easy-to-obtain features that could guide antibiotic prophylaxis.

PMID:35942941 | DOI:10.1111/tid.13920

Biometrics. 2022 Aug 9. doi: 10.1111/biom.13732. Online ahead of print.

ABSTRACT

Mendelian randomization (MR) utilizes genetic variants as instrumental variables (IVs) to estimate the causal effect of an exposure variable on an outcome of interest even in the presence of unmeasured confounders. However, the popular inverse-variance weighted (IVW) estimator could be biased in the presence of weak IVs, a common challenge in MR studies. In this article, we develop a novel penalized inverse-variance weighted (pIVW) estimator, which adjusts the original IVW estimator to account for the weak IV issue by using a penalization approach to prevent the denominator of the pIVW estimator from being close to zero. Moreover, we adjust the variance estimation of the pIVW estimator to account for the presence of balanced horizontal pleiotropy. We show that the recently proposed debiased IVW (dIVW) estimator is a special case of our proposed pIVW estimator. We further prove that the pIVW estimator has smaller bias and variance than the dIVW estimator under some regularity conditions. We also conduct extensive simulation studies to demonstrate the performance of the proposed pIVW estimator. Furthermore, we apply the pIVW estimator to estimate the causal effects of five obesity-related exposures on three coronavirus disease 2019 (COVID-19) outcomes. Notably, we find that hypertensive disease is associated with an increased risk of hospitalized COVID-19; and peripheral vascular disease and higher body mass index are associated with increased risks of COVID-19 infection, hospitalized COVID-19 and critically ill COVID-19. This article is protected by copyright. All rights reserved.

PMID:35942938 | DOI:10.1111/biom.13732