Predicting early recovery of consciousness after cardiac arrest supported by quantitative electroencephalography.

OBJECTIVE: To determine the ability of quantitative electroencephalography (QEEG) to improve the accuracy of predicting recovery of consciousness by post-cardiac arrest day 10. METHODS: Unconscious survivors of cardiac arrest undergoing daily clinical and EEG assessments through post-cardiac arrest day 10 were studied in a prospective observational cohort study. Power spectral density, local coherence, and permutation entropy were calculated from daily EEG clips following a painful stimulus. Recovery of consciousness was defined as following at least simple commands by day 10. We determined the impact of EEG metrics to predict recovery when analyzed with established predictors of recovery using partial least squares regression models. Explained variance analysis identified which features contributed most to the predictive model. RESULTS: 367 EEG epochs from 98 subjects were analyzed in conjunction with clinical measures. Highest prediction accuracy was achieved when adding QEEG features from post-arrest days 4-6 to established predictors (area under the receiver operating curve improved from 0.81 ± 0.04 to 0.86 ± 0.05). Prediction accuracy decreased from 0.84 ± 0.04 to 0.79 ± 0.04 when adding QEEG features from post-arrest days 1-3. Patients with recovery of command-following by day 10 showed higher coherence across the frequency spectrum and higher centro-occipital delta-frequency spectral power by days 4-6, and globally-higher theta range permutation entropy by days 7-10. CONCLUSIONS: Adding quantitative EEG metrics to established predictors of recovery allows modest improvement of prediction accuracy for recovery of consciousness, when obtained within a week of cardiac arrest. Further research is needed to determine the best strategy for integration of QEEG data into prognostic models in this patient population.

Serial block-face scanning electron microscopy reveals novel intercellular connections in human term placental microvasculature.

The placental microvasculature is a conduit for fetal blood allowing solute exchange between the mother and the fetus. Serial block-face scanning electron microscopy (SBF SEM) allows ultrastructure to be viewed in three dimensions and provides a new perspective on placental anatomy. This study used SBF SEM to study endothelial cells within the human placental microvasculature from uncomplicated pregnancies. Term human placental villi were aldehyde-fixed and processed for imaging by SBF SEM. Manual segmentation was carried out on a terminal villous capillary and an intermediate villous arteriole and venule. Twenty-seven SBF SEM stacks from terminal villi were analysed using stereological approaches to determine the volumes of microvascular components and the proportions of pericyte coverage. SBF SEM analysis of capillary endothelial cells revealed the presence of interendothelial protrusions (IEPs) originating from the donor cell at the endothelial junction and forming deep thin projections up to 7 µm into the adjacent endothelial cells. IEP density was estimated to be in the order of 35 million cm-3 placental tissue. Pericytes cover 15% of the fetal capillary surface area in terminal villi. In comparison, the cytotrophoblast covered 24% of the syncytiotrophoblast basal membrane. A trans-endothelial channel was observed in a region of the vasculo-syncytial capillary. Pericyte coverage was extensive in both arteriole and venule. Three-dimensional imaging of the placental microvasculature identified novel ultrastructural features and provided an insight into factors that may influence capillary permeability and placental function. We hypothesise that the IEPs may allow mechanosensing between adjacent endothelial cells to assist in the maintenance of vessel integrity. The numbers of endothelial junctions, the presence of trans-endothelial channels and the extent of pericyte coverage all provide an insight into the factors determining capillary permeability.

Speak-up culture in an intensive care unit in Hong Kong: a cross-sectional survey exploring the communication openness perceptions of Chinese doctors and nurses.

OBJECTIVES: Despite growing recognition of the importance of speaking up to protect patient safety in critical care, little research has been performed in this area in an intensive care unit (ICU) context. This study explored the communication openness perceptions of Chinese doctors and nurses and identified their perceptions of issues in ICU communication, their reasons for speaking up and the possible factors and strategies involved in promoting the practice of speaking up. DESIGN: A mixed-methods design with quantitative and sequential qualitative components was used. SETTING AND PARTICIPANTS: Eighty ICU staff members from a large public hospital in Hong Kong completed a questionnaire regarding their perceptions of communication openness. Ten clinicians whose survey responses indicated support for open communication were then interviewed about their speak-up practices. RESULTS: The participating ICU staff members had similar perceptions of their openness to communication. However, the doctors responded more positively than the nurses to many aspects of communication openness. The two groups also had different perceptions of speaking up. The interviewed ICU staff members who indicated a high level of communication openness reported that their primary reasons for speaking up were to seek and clarify information, which was achieved by asking questions. Other factors perceived to influence the motivation to speak up included seniority, relationships and familiarity with patient cases. CONCLUSIONS: Creating an atmosphere of safety and equality in which team members feel confident in expressing their personal views without fear of reprisal or embarrassment is necessary to encourage ICU staff members, regardless of their position, to speak up. Because harmony and saving face is valued in Chinese culture, training nurses and doctors to speak up by focusing on human factors and values rather than simply addressing conflict management is desirable in this context.

How can we improve targeting of frail elderly patients to a geriatric day-hospital rehabilitation program?

BACKGROUND: The optimal patient selection of frail elderly persons undergoing rehabilitation in Geriatric Day Hospital (GDH) programs remains uncertain. This study was done to identify potential predictors of rehabilitation outcomes for these patients. METHODS: This study is a retrospective cohort analysis of patients admitted to the rehabilitation program of our GDH, in Montreal, Canada, over a five year period. The measures considered were: Barthel Index, Older Americans Resources and Services, Folstein Mini Mental Status Exam, Timed Up & Go (TUG), 6-minute walk test (6 MWT), Gait speed, Berg Balance, grip strength and the European Quality of life - 5 Dimensions. Successful improvement with rehabilitation was defined as improvement in three or more tests of physical function. Logistic regression analysis using the Bayesian Information Criterion (BIC) was employed to select the optimal model for making predictions of rehabilitation success. RESULTS: A total of 335 patients were studied, but only 233 patients had a complete data set suitable for the predictive model. Average age was 81 years and patients attended the GDH an average of 24 visits. Significant changes were found in several measures of physical performance for many patients ranging from improved gait speed in 21.3% to improved TUG in 62.7% of the cohort. Fifty-eight percent of patients attained successful improvement with rehabilitation by our criteria. This group was characterized by lower test scores on admission. Using BIC, the best predictor model was the 6 MWT [OR: 0.994 per meter walked (95% CI: 0.990-0.997)]. CONCLUSIONS: The GDH rehabilitation program is effective in improving patients' physical performance. Although no single measure was found to be sufficiently predictive to help target candidates appropriately, the 6 MWT showed a trend to significance. Further research will be done to elucidate the utility of a composite 'rehab appropriateness index' and the role of International Classification of Function concepts for targeting frail elderly to GDH rehabilitation services.

From the facts to the screen: a blended model of teaching basic hospital skills to 2nd year medical students.

We report an interactive course design which simulated the clinical setting for practicing basic hospital skills. The two-part course included (1) instructor-led, Flash-based interactive lectures; and (2) web-based case using interactive hospital forms. Our program evaluation showed that integrated sessions complemented with web-based interactive cases and hospital forms offered a better student preparation for the Geriatric Medicine clerkship and improved tutor perceptions of student performance during early rotations in the academic year.