Multicenter Study Evaluating Nitrous Oxide Use for Labor Analgesia at High- and Low-Altitude Institutions.

BACKGROUND: Nitrous oxide (N2O) has been used nationally as an analgesic in many clinical settings. While neuraxial analgesia is still the most commonly used labor analgesic in the United States, there is increasing use of N2O in labor. Given the reduction in the partial pressure of gases at a higher altitude, N2O has been reported to have reduced analgesic properties. However, there is no study to date evaluating the impact of altitude on labor analgesia and N2O. METHODS: We conducted a multicenter retrospective data analysis of a N2O registry collected from 4 institutions over a 3-year period. We compared the impact of altitude on 50% N2O administration for labor analgesia, conversion rates to another analgesic modality, as well as collected side effect frequencies and conversion predictors. Multivariable regression models were used to compare clinical characteristics and outcomes between parturients at high and low altitudes, while adjusting for race, ethnicity, education, and age (logistic and linear regressions for categorical and quantitative outcomes, respectively). RESULTS: A total of 1856 laboring parturients (age 18-50) were included in the analysis. The odds of converting from 50% N2O to another analgesic modality had no statistically significant difference between high- versus low-altitude institutions (adjusted odds ratio [aOR], 1.13; 95% confidence interval [CI], 0.90-1.42; P = .3). Yet, when parturients at low altitude converted from N2O, they were more likely (aOR, 3.03; 95% CI, 1.59-5.88) to choose neuraxial analgesia instead of another analgesic modality when compared to high-altitude parturients. This is possibly due to higher epidural rates at the low-altitude institutions. When parturients at high altitude did convert into another modality, they were more likely (aOR, 2.19; 95% CI, 1.14-4.21) to convert due to inadequate pain relief compared to low-altitude parturients; however, missing data may have affected this finding. Laboring individuals at low altitude were significantly more likely to experience side effects (aOR, 2.13; 95% CI, 1.45-3.12). Those requiring labor augmentation, assisted vaginal, or cesarean delivery converted to neuraxial analgesia significantly more often than those that delivered via spontaneous vaginal delivery (P < .05) in both high- and low-altitude groups. CONCLUSIONS: This is the first study evaluating 50% N2O as a labor analgesic at high altitude. As expected, we found lower side effects at high altitude, likely due to the lower partial pressure of N2O. However, there was not a statistically significant increase in conversion from N2O to another analgesic modality at high altitude and no clinically significant differences in neonatal outcomes.

Introducing Benzene-1,3,5-tri(dithiocarboxylate) as a Multidentate Linker in Coordination Chemistry.

Benzene-1,3,5-tri(dithiocarboxylate) (BTDTC3-), the sulfur-donor analogue of trimesate (BTC3-, benzene-1,3,5-tricarboxylate), is introduced, and its potential as a multidentate, electronically bridging ligand in coordination chemistry is evaluated. For this, the sodium salt Na3BTDTC has been synthesized, characterized, and compared with the sodium salt of the related ditopic benzene-1,4-di(dithiocarboxylate) (Na2BDDTC). Single-crystal X-ray diffraction of the respective tetrahydrofuran (THF) solvates reveals that such multitopic aromatic dithiocarboxylate linkers can form both discrete metal complexes (Na3BTDTC·9THF) and (two-dimensional) coordination polymers (Na2BDDTC·4THF). Additionally, the versatile coordination behavior of the novel BTDTC3- ligand is demonstrated by successful synthesis and characterization of trinuclear Cu(I) and hexanuclear Mo(II)2 paddlewheel complexes. The electronic structure and molecular orbitals of both dithiocarboxylate ligands as well as their carboxylate counterparts are investigated by density functional theory computational methods. Electrochemical investigations suggest that BTDTC3- enables electronic communication between the coordinated metal ions, rendering it a promising tritopic linker for functional coordination polymers.

Investigation of Solvatomorphism and Its Photophysical Implications for Archetypal Trinuclear Au3(1-Methylimidazolate)3.

A new solvatomorph of [Au3(1-Methylimidazolate)3] (Au3(MeIm)3)-the simplest congener of imidazolate-based Au(I) cyclic trinuclear complexes (CTCs)-has been identified and structurally characterized. Single-crystal X-ray diffraction revealed a dichloromethane solvate exhibiting remarkably short intermolecular Au⋯Au distances (3.2190(7) Å). This goes along with a dimer formation in the solid state, which is not observed in a previously reported solvent-free crystal structure. Hirshfeld analysis, in combination with density functional theory (DFT) calculations, indicates that the dimerization is generally driven by attractive aurophilic interactions, which are commonly associated with the luminescence properties of CTCs. Since Au3(MeIm)3 has previously been reported to be emissive in the solid-state, we conducted a thorough photophysical study combined with phase analysis by means of powder X-ray diffraction (PXRD), to correctly attribute the photophysically active phase of the bulk material. Interestingly, all investigated powder samples accessed via different preparation methods can be assigned to the pristine solvent-free crystal structure, showing no aurophilic interactions. Finally, the observed strong thermochromism of the solid-state material was investigated by means of variable-temperature PXRD, ruling out a significant phase transition being responsible for the drastic change of the emission properties (hypsochromic shift from 710 nm to 510 nm) when lowering the temperature down to 77 K.

Nitrous Oxide Use During Labor: Satisfaction, Adverse Effects, and Predictors of Conversion to Neuraxial Analgesia.

INTRODUCTION: Women desire safe and effective choices for pain management during labor. Currently, neuraxial and opioid analgesia are the most common methods used in the United States. The purpose of this study was to investigate demographic characteristics, safety, and satisfaction in a cohort of parturients who used inhaled nitrous oxide (N2 O) analgesia and to determine predictors of conversion from N2 O to neuraxial analgesia. METHODS: This was a prospective chart review study. Individuals aged at least 18 years who used inhaled N2 O during the first or second stage of labor between March 1, 2016, and July 23, 2017, on the labor and delivery unit of one academic medical center (N = 463) and their neonates were included. Data describing maternal and neonatal factors are reported. Logistic regression and chi-square tests were used to model the effects of oxytocin augmentation, labor induction, parity, prior cesarean birth, pre-N2 O cervical dilatation, and post-N2 O cervical dilatation on the odds of conversion from N2 O to neuraxial analgesia. RESULTS: In this cohort, 31% who chose N2 O for analgesia did not convert to any other analgesic method. Significant positive predictors for conversion from N2 O to neuraxial analgesia included labor induction (odds ratio [OR], 2.9; 95% CI, 1.7-5.0), oxytocin augmentation (OR, 3.1; 95% CI, 1.6-6.0), and labor after cesarean (OR, 6.4; 95% CI, 2.5-16.5). Multiparity (OR, 0.4; 95% CI, 0.2-0.6) and post-N2 O cervical dilatation (OR, 0.8; 95% CI, 0.7-0.9) were negative predictors. Adverse effects related to N2 O use during labor were rare (8%) and were not a significant reason for conversion to neuraxial analgesia. Parturients had moderately high satisfaction with N2 O for pain management (11-point scale, mean [SD], 7.4 [2.9]). Five-minute Apgar scores were 7 or greater in 97.8% of the newborns. DISCUSSION: Understanding predictors of conversion from inhaled N2 O to neuraxial analgesia may assist perinatal care providers in their discussions with women about analgesia options during labor. N2 O is a useful, safe option for labor analgesia in the United States.

Controlling Multiphoton Absorption Efficiency by Chromophore Packing in Metal-Organic Frameworks.

Coordination polymers show great potential for the tailored design of advanced photonic applications by employing crystal chemistry concepts. One challenge for achieving a rational design of nonlinear optically active MOF materials is deriving fundamental structure-property relations of the interplay between the photonic properties and the spatial arrangements of optically active chromophores within the network. We here investigate two-photon-absorption (TPA)-induced photoluminescence of two new MOFs based on a donor-acceptor tetraphenylphenylenediamine (tPPD) chromophore linker (H4TPBD) and Zn(II) and Cd(II) as metal centers. The TPA efficiencies are controlled by the network topologies, degree of interpenetration, packing densities, and the specific spatial arrangement of the chromophores. The effects can be rationalized within the framework of established excited-state theories of molecular crystals. The results presented here demonstrate the key effect of chromophore orientation on the nonlinear optical properties of crystalline network compounds and allow for establishing quantitative design principles for efficient TPA materials.

Non-Innocent Methylene Linker in Bridged Lewis Pair Initiators.

Deprotonation usually occurs as an unwanted side reaction in the Lewis pair polymerization of Michael acceptors, for which the conjugated addition of the Lewis base to the acid-activated monomer is the commonly accepted initiation mechanism. This has also been reported for B-P-based bridged Lewis pairs (BLPs) that form macrocyclic addition products. We now show that the formerly unwanted deprotonation is the likely initiation pathway in the case of Al-P-based BLPs. In a detailed study of a series of Al-P-based BLPs, using a combination of single-crystal diffraction experiments (X-ray and neutron) and mechanistic investigations (experimental and computational), an active role of the methylene bridge was revealed, acting as a base towards the α-acidic monomers. Additionally, the polymerization studies proved a living behavior combined with significantly high activities, narrow molecular mass distributions, and the possibility of copolymerization.

Results of a Flipped Classroom Teaching Approach in Anesthesiology Residents.

BACKGROUND: In a flipped classroom approach, learners view educational content prior to class and engage in active learning during didactic sessions. OBJECTIVE: We hypothesized that a flipped classroom improves knowledge acquisition and retention for residents compared to traditional lecture, and that residents prefer this approach. METHODS: We completed 2 iterations of a study in 2014 and 2015. Institutions were assigned to either flipped classroom or traditional lecture for 4 weekly sessions. The flipped classroom consisted of reviewing a 15-minute video, followed by 45-minute in-class interactive sessions with audience response questions, think-pair-share questions, and case discussions. The traditional lecture approach consisted of a 55-minute lecture given by faculty with 5 minutes for questions. Residents completed 3 knowledge tests (pretest, posttest, and 4-month retention) and surveys of their perceptions of the didactic sessions. A linear mixed model was used to compare the effect of both formats on knowledge acquisition and retention. RESULTS: Of 182 eligible postgraduate year 2 anesthesiology residents, 155 (85%) participated in the entire intervention, and 142 (78%) completed all tests. The flipped classroom approach improved knowledge retention after 4 months (adjusted mean = 6%; P = .014; d = 0.56), and residents preferred the flipped classroom (pre = 46%; post = 82%; P < .001). CONCLUSIONS: The flipped classroom approach to didactic education resulted in a small improvement in knowledge retention and was preferred by anesthesiology residents.

A Novel Core Competencies-Based Academic Medicine Curriculum: Description and Preliminary Results.

BACKGROUND: Physicians practice health care in a rapidly changing system that requires more than the delivery of safe and effective care. Modern physicians must also acquire skills beyond direct patient care. Residency programs must, therefore, prepare physicians to meet these demands by providing appropriate education and training. METHODS: We designed, implemented and assessed an academic medicine curriculum in the first post-graduate year. This curriculum provides comprehensive exposure to necessary non-patient contact related physician skills. Topics centered around four domains: critical appraisal of literature of literature, quality improvement, professional development, and teaching. Each of these domains is linked to the six core competencies established by the Accreditation Council for Graduate Medical Education's (ACGME). Instruction includes small-group learning sessions with additional time for self-directed online modules and a faculty-mentored quality improvement research project that is presented at a graduation symposium. All residents completed a survey evaluation of the curriculum before and after the course via open-ended questions and Likert responses (0-5). We assessed improvement in resident confidence with each curricular domain using mean Likert score change and 95% confidence intervals (CI). RESULTS: Residents improved at all curricular domains measured. The most significant mean changes included confidence in: poster presentations (2.7; 95% CI: 1.9-3.5), plan-do-check-act cycle (2.5; 95% CI: 2.1-2.9), quality improvement projects (2.4; 95% CI: 1.9-2.9), and abstract presentation (2.3; 95% CI: 1.6-3.0). CONCLUSIONS: We found that the academic medicine rotation (AMR) is feasible in a large academic setting. Furthermore, the AMR allows early exposure to and improvement in essential non-patient contact related physician skills required by the ACGME core competencies and assessed through the milestones.

Enhancement of anesthesiology in-training exam performance with institution of an academic improvement policy.

BACKGROUND: Anesthesiology resident physicians across the United States complete an annual in-training examination (ITE). The ITE evaluates resident knowledge and provides personalized feedback to guide future study in low scoring sections(1). Performance on the ITE correlates with outcomes on the American Board of Anesthesiology (ABA) written board examination(2). Over the last several years, declining ITE scores were observed at the University of North Carolina (UNC). In response to this decline, our department reprioritized the ITE by instituting an academic improvement policy (AIP). The AIP employed both reward for satisfactory achievement and consequence for under-performance to elevate the ITE as a "high stakes" examination. Our hypothesis was that implementation of this AIP would improve ITE scores. METHODS: ITE scores were compiled from 150 residents in the Department of Anesthesiology at UNC for graduating classes from 2004-2015. Data is presented as the number of residents scoring below the 20th percentile when compared to the national distribution before and after the AIP. In addition, average USMLE Step 1 three-digit scores for each graduating class were compared to average ITE percentile scores of the corresponding graduating class (USMLE does not provide percentile scores). RESULTS: Between 2009 and 2013, the number of residents who scored below the 20th percentile on the ITE increased steadily to a peak of 10 in 2011. After implementation of the AIP in July 2011, there was an 80% decrease in those scoring below the 20th percentile, from 10 to 2 residents (p<0.05). CONCLUSIONS: Anesthesiology resident ITE scores improved after implementation of an academic improvement policy.

Get on your boots: preparing fourth-year medical students for a career in surgery, using a focused curriculum to teach the competency of professionalism.

INTRODUCTION: Few educational programs exist for medical students that address professionalism in surgery, even though this core competency is required for graduate medical education and maintenance of board certification. Lapses in professional behavior occur commonly in surgical disciplines, with a negative effect on the operative team and patient care. Therefore, education regarding professionalism should begin early in the surgeon's formative process, to improve behavior. The goal of this project was to enhance the attitudes and knowledge of medical students regarding professionalism, to help them understand the role of professionalism in a surgical practice. METHODS: We implemented a 4-h seminar, spread out as 1-h sessions over the course of their month-long rotation, for 4th-year medical students serving as acting interns (AIs) in General Surgery, a surgical subspecialty, Obstetrics/Gynecology, or Anesthesia. Teaching methods included lecture, small group discussion, case studies, and journal club. Topics included Cognitive/Ethical Basis of Professionalism, Behavioral/Social Components of Professionalism, Managing Yourself, and Leading While You Work. We assessed attitudes about professionalism with a pre-course survey and tracked effect on learning and behavior with a post-course questionnaire. We asked AIs to rate the egregiousness of 30 scenarios involving potential lapses in professionalism. RESULTS: A total of 104 AIs (mean age, 26.5 y; male to female ratio, 1.6:1) participated in our course on professionalism in surgery. Up to 17.8% of the AIs had an alternate career before coming to medical school. Distribution of intended careers was: General Surgery, 27.4%; surgical subspecialties, 46.6%; Obstetrics/Gynecology, 13.7%; and Anesthesia, 12.3%. Acting interns ranked professionalism as the third most important of the six core competencies, after clinical skills and medical knowledge, but only slightly ahead of communication. Most AIs believed that professionalism could be taught and learned, and that the largest obstacle was not enough time in the curriculum. The most effective reported teaching methods were mentoring and modeling; lecture and journal club were the effective. Regarding attitudes toward professionalism, the most egregious examples of misconduct were substance abuse, illegal billing, boundary issues, sexual harassment, and lying about patient data, whereas the least egregious examples were receiving textbooks or honoraria from drug companies, advertising, self-prescribing for family members, and exceeding work-hour restrictions. The most important attributes of the professional were integrity and honesty, whereas the least valued were autonomy and altruism. The AIs reported that the course significantly improved their ability to define professionalism, identify attributes of the professional, understand the importance of professionalism, and integrate these concepts into practice (all P < 0.01). CONCLUSIONS: Although medical students interested in surgery may already have well-formed attitudes and sophisticated knowledge about professionalism, this core competency can still be taught to and learned by trainees pursuing a surgical career.