Preoperative electroencephalographic alpha-power changes with eyes opening are associated with postoperative attention impairment and inattention-related delirium severity.

BACKGROUND: In the eyes-closed, awake condition, EEG oscillatory power in the alpha band (7-13 Hz) dominates human spectral activity. With eyes open, however, EEG alpha power substantially decreases. Less alpha attenuation with eyes opening has been associated with inattention; thus, we analysed whether reduced preoperative alpha attenuation with eyes opening is associated with postoperative inattention, a delirium-defining feature. METHODS: Preoperative awake 32-channel EEG was recorded with eyes open and eyes closed in 71 non-neurological, noncardiac surgery patients aged ≥ 60 years. Inattention and other delirium features were assessed before surgery and twice daily after surgery until discharge. Eyes-opening EEG alpha-attenuation magnitude was analysed for associations with postoperative inattention, primarily, and with delirium severity, secondarily, using multivariate age- and Mini-Mental Status Examination (MMSE)-adjusted logistic and proportional-odds regression analyses. RESULTS: Preoperative alpha attenuation with eyes opening was inversely associated with postoperative inattention (odds ratio [OR] 0.73, 95% confidence interval [CI]: 0.57, 0.94; P=0.038). Sensitivity analyses showed an inverse relationship between alpha-attenuation magnitude and inattention chronicity, defined as 'never', 'newly', or 'chronically' inattentive (OR 0.76, 95% CI: 0.62, 0.93; P=0.019). In addition, preoperative alpha-attenuation magnitude was inversely associated with postoperative delirium severity (OR 0.79, 95% CI: 0.65, 0.95; P=0.040), predominantly as a result of the inattention feature. CONCLUSIONS: Preoperative awake, resting, EEG alpha attenuation with eyes opening might represent a neural biomarker for risk of postoperative attentional impairment. Further, eyes-opening alpha attenuation could provide insight into the neural mechanisms underlying postoperative inattention risk.

Effects of submersion on VO2: comparing maximum aerobic exertion on land and underwater.

Introduction: Submersion results in blood redistribution into the pulmonary circulation, causing changes in pulmonary compliance and increased cardiac preload. Few studies have compared incremental exercise to exhaustion (VO2 max testing) in a dry environment with exercise underwater. We hypothesized that the physiological effects of submersion would result in lower heart rate (HR), minute ventilation (VE), and peak oxygen uptake (VO2 peak) compared with dry conditions. Methods: Fourteen male and four female volunteers completed two VO2 peak testing sessions with approximately two hours between trials: first in the dry laboratory on a cycle ergometer and second while fully submersed in a prone position with zero static lung load. HR was monitored via ECG, and inspiratory and expiratory gas compositions were recorded using a metabolic cart. The tests were terminated once the subject reached exhaustion. Results: Absolute VO2 peak was lower in the submersed VO2 max trial (37.1 ± 7.0 mL•kg-1•min-1) compared with dry exercise (45.8 ± 8.9 mL•kg-1•min-1) p < 0.001. HR and VE were also lower in the submersed trial. Conclusions: VO2 peak while submersed is reduced relative to dry VO2 peak, which may be partly due to a decrease in heart rate and a reduction in VE.

The Role of Recipient Thyroid Hormone Supplementation in Primary Graft Dysfunction After Heart Transplantation: A Propensity-Adjusted Analysis.

OBJECTIVES: To investigate whether recipient administration of thyroid hormone (liothyronine [T3]) is associated with reduced rates of primary graft dysfunction (PGD) after orthotopic heart transplantation. DESIGN: Retrospective cohort study. SETTING: Single-center, university hospital. PARTICIPANTS: Adult patients undergoing orthotopic heart transplantation. INTERVENTIONS: A total of 609 adult heart transplant recipients were divided into 2 cohorts: patients who did not receive T3 (no T3 group, from 2009 to 2014), and patients who received T3 (T3 group, from 2015 to 2019). Propensity-adjusted logistic regression was performed to assess the association between T3 supplementation and PGD. MEASUREMENTS AND MAIN RESULTS: After applying exclusion criteria and propensity-score analysis, the final cohort included 461 patients. The incidence of PGD was not significantly different between the groups (33.9% no T3 group v 40.8% T3 group; p = 0.32). Mortality at 30 days (3% no T3 group v 2% T3 group; p = 0.53) and 1 year (10% no T3 group v 12% T3 group; p = 0.26) were also not significantly different. When assessing the severity of PGD, there were no differences in the groups' rates of moderate PGD (not requiring mechanical circulatory support other than an intra-aortic balloon pump) or severe PGD (requiring mechanical circulatory support other than an intra-aortic balloon pump). However, segmented time regression analysis revealed that patients in the T3 group were less likely to develop severe PGD. CONCLUSIONS: These findings indicated that recipient single-dose thyroid hormone administration may not protect against the development of PGD, but may attenuate the severity of PGD.

Perioperative neurocognitive and functional neuroimaging trajectories in older APOE4 carriers compared with non-carriers: secondary analysis of a prospective cohort study.

BACKGROUND: Cognitive dysfunction after surgery is a major issue in older adults. Here, we determined the effect of APOE4 on perioperative neurocognitive function in older patients. METHODS: We enrolled 140 English-speaking patients ≥60 yr old scheduled for noncardiac surgery under general anaesthesia in an observational cohort study, of whom 52 underwent neuroimaging. We measured cognition; Aß, tau, p-tau levels in CSF; and resting-state intrinsic functional connectivity in six Alzheimer's disease-risk regions before and 6 weeks after surgery. RESULTS: There were no significant APOE4-related differences in cognition or CSF biomarkers, except APOE4 carriers had lower CSF Aß levels than non-carriers (preoperative median CSF Aß [median absolute deviation], APOE4 305 pg ml-1 [65] vs 378 pg ml-1 [38], respectively; P=0.001). Controlling for age, APOE4 carriers had significantly greater preoperative functional connectivity than non-carriers between several brain regions implicated in Alzheimer's disease, including between the left posterior cingulate cortex and left angular gyrus (ß [95% confidence interval, CI], 0.218 [0.137-0.230]; PFWE=0.016). APOE4 carriers, but not non-carriers, experienced significant connectivity decreases from before to 6 weeks after surgery between several brain regions including between the left posterior cingulate cortex and left angular gyrus (ß [95% CI], -0.196 [-0.256 to -0.136]; PFWE=0.001). Most preoperative and postoperative functional connectivity differences did not change after controlling for preoperative CSF Aß levels. CONCLUSIONS: Postoperative change trajectories for cognition and CSF Aß, tau or p-tau levels did not differ between community dwelling older APOE4 carriers and non-carriers. APOE4 carriers showed greater preoperative functional connectivity and greater postoperative decreases in functional connectivity in key Alzheimer's disease-risk regions, which occur via Aß-independent mechanisms.

Spaced learning using emails to integrate psychiatry into general medical curriculum: Keep psychiatry in mind.

OBJECTIVES: Traditionally, medical students on clinical rotations receive instruction on principles of mental health only during the psychiatry clerkship. We used emails to insert teaching of psychiatric concepts beyond the psychiatry clerkship into other rotations using the method of spaced learning, the delivery of brief morsels of information repeated over time intervals. We predicted that the intervention would improve attitudes and confidence towards the integration of psychiatry and knowledge retention. METHODS: We developed and distributed a series of emails relating key psychiatric concepts targeted to the other core clerkships. RESULTS: In a cluster-randomized trial over one academic year (intervention group n = 71, control group n = 61), scores on the Attitudes and Confidence in the Integration of Psychiatry scale and on the knowledge quiz did not differ significantly. Students who actively engaged with the emails demonstrated significantly higher scores on the knowledge test. Email users valued the timing, format of delivery and application of psychiatric principles outside the psychiatric setting. Participants recommended simplifying the format and previewing the benefits of spaced learning to increase utilization. CONCLUSION: Delivering spaced learning through emails, within a curriculum designed to foster engagement, may provide an efficient means of addressing the widely-recognized but elusive goal of integrating teaching across medical disciplines.

Textbook outcome in lung transplantation: Planned venoarterial extracorporeal membrane oxygenation versus off-pump support for patients without pulmonary hypertension.

BACKGROUND: Planned venoarterial extracorporeal membrane oxygenation (VA ECMO) is increasingly used during bilateral orthotopic lung transplantation (BOLT) and may be superior to off-pump support for patients without pulmonary hypertension. In this single-institution study, we compared rates of textbook outcome between BOLTs performed with planned VA ECMO or off-pump support for recipients with no or mild pulmonary hypertension. METHODS: Patients with no or mild pulmonary hypertension who underwent isolated BOLT between 1/2017 and 2/2021 with planned off-pump or VA ECMO support were included. Textbook outcome was defined as freedom from intraoperative complication, 30-day reintervention, 30-day readmission, post-transplant length of stay >30 days, 90-day mortality, 30-day acute rejection, grade 3 primary graft dysfunction at 48 or 72 hours, post-transplant ECMO, tracheostomy within 7 days, inpatient dialysis, reintubation, and extubation >48 hours post-transplant. Textbook outcome achievement was compared between groups using multivariable logistic regression. RESULTS: Two hundred thirty-seven BOLTs were included: 68 planned VA ECMO and 169 planned off-pump. 14 (20.6%) planned VA ECMO and 27 (16.0%) planned off-pump patients achieved textbook outcome. After adjustment for prior BOLT, lung allocation score, ischemic time, and intraoperative transfusions, planned VA ECMO was associated with higher odds of textbook outcome than planned off-pump support (odds ratio 3.89, 95% confidence interval 1.58-9.90, p = 0.004). CONCLUSIONS: At our institution, planned VA ECMO for isolated BOLT was associated with higher odds of textbook outcome than planned off-pump support among patients without pulmonary hypertension. Further investigation in a multi-institutional cohort is warranted to better elucidate the utility of this strategy.

Longitudinal Assessment of Critical Thinking Skills Across a Dental Curriculum.

Critical thinking and problem-solving are two of the most frequently desired goals for dental student learning, but greater understanding is needed of how students' critical thinking skills develop from the beginning to the end of the curriculum. The aim of this study was to use students' performance on critical thinking assessments at five time points from the first to the fourth years to longitudinally assess their critical thinking development across the curriculum. In 2014-16, the performance of students in two successive graduating classes at one U.S. dental school was collected from five assignments designed to, among other things, assess critical thinking. Those assignments ranged from a case study in the Cariology I course in fall of the first year to an OSCE completed before graduation. Students were divided into four quartiles from lowest- to highest-achieving based on the first (baseline) assessment, and those quartiles were tracked to determine each student's progress over the four years. The results showed that, for both cohorts, students who ranked in the top quartile remained in the top of the class for all subsequent assessments. Also in both cohorts, the students who had the lowest scores on the initial assessment of critical thinking skills showed statistically significant improvements over time, increasing their scores by 9.4% (cohort 1, p<0.001) and 4.6% (cohort 2, p=0.003) in each consecutive assessment. These results suggest that implementing critical thinking assessments early in the curriculum can assist in predicting students' future performance on critical thinking assessments. Furthermore, a dental curriculum intentionally designed to promote critical thinking capacities can help students improve these skills over time, whatever their level at the beginning.

Making sense of data: How public health graduate students build theory through qualitative research techniques.

Data interpretation and theory building are two key skills often taught in health sciences qualitative methods courses. However, little is known about how novice researchers make sense of data, as well as how their thought processes differ from those of expert researchers. In this classroom research project, the author explores how qualitative methods students in a public health graduate program describe their processes of making sense of data and building theory. She then compares these processes with "expert" guidelines to draw implications for how to enhance teaching in a qualitative research class.

Effects of image-based and text-based active learning exercises on student examination performance in a musculoskeletal anatomy course.

Research on the benefits of visual learning has relied primarily on lecture-based pedagogy, but the potential benefits of combining active learning strategies with visual and verbal materials on learning anatomy has not yet been explored. In this study, the differential effects of text-based and image-based active learning exercises on examination performance were investigated in a functional anatomy course. Each class session was punctuated with an average of 12 text-based and image-based active learning exercises. Participation data from 231 students were compared with their examination performance on 262 questions associated with the in-class exercises. Students also rated the helpfulness and difficulty of the in-class exercises on a survey. Participation in the active learning exercises was positively correlated with examination performance (r = 0.63, P < 0.001). When controlling for other key demographics (gender, underrepresented minority status) and prior grade point average, participation in the image-based exercises was significantly correlated with performance on examination questions associated with image-based exercises (P < 0.001) and text-based exercises (P < 0.01), while participation in text-based exercises was not. Additionally, students reported that the active learning exercises were helpful for seeing images of key ideas (94%) and clarifying key course concepts (80%), and that the image-based exercises were significantly less demanding, less hard and required less effort than text-based exercises (P < 0.05). The findings confirm the positive effect of using images and active learning strategies on student learning, and suggest that integrating them may be especially beneficial for learning anatomy. Anat Sci Educ 10: 444-455. © 2017 American Association of Anatomists.

Association Between Dental Student-Developed Exam Questions and Learning at Higher Cognitive Levels.

New dental accreditation standards emphasize that graduates must be competent in the use of critical thinking (a high cognitive-level skill). Despite this new standard, most written assessments in dental school courses are still based on low cognitive-level questions. The aim of this study was to determine if an exercise that allows students to collaboratively write exam questions would help cultivate higher cognitive levels of learning. To evaluate this exercise at one U.S. dental school, the cognitive level (according to Bloom's taxonomy) of multiple-choice exam questions and students' scores across two cohorts in a cariology course were compared. This evaluation took place using a control group in which questions were instructor-generated and an intervention group in which students worked in groups to develop questions. All students in one first-year class participated in the intervention group (n=104); all students in the first-year class two years earlier served as the control group (n=106). Among students in the intervention group, the response rate to a post-intervention survey measuring students' attitudes about the experience was 70% (N=73). The results showed that the students generating their own assessments developed higher cognitive-level exam questions than the instructor-generated assessments. The intervention group (with student-generated assessments) also performed as well or better on tests compared to the control group (with instructor-generated assessments). In the intervention group survey, the vast majority of students agreed that the exercise was helpful for their overall learning experience, but working in teams was said to be the least valuable component of the activity for their learning. This study suggests that student-driven, collaborative assessments can be an important tool for building critical thinking skills in dental classrooms and that it may be worthwhile to expand this type of exercise into other courses.