Using synchronized brain rhythms to bias memory-guided decisions

Functional interactions between the prefrontal cortex and hippocampus, as revealed by strong oscillatory synchronization in the theta (6-11 Hz) frequency range, correlate with memory-guided decision-making. However, the degree to which this form of long-range synchronization influences memory-guided choice remains unclear. We developed a brain machine interface that initiated task trials based on the magnitude of prefrontal hippocampal theta synchronization, then measured choice outcomes. Trials initiated based on strong prefrontal-hippocampal theta synchrony were more likely to be correct compared to control trials on both working memory-dependent and -independent tasks. Prefrontal-thalamic neural interactions increased with prefrontal-hippocampal synchrony and optogenetic activation of the ventral midline thalamus primarily entrained prefrontal theta rhythms, but dynamically modulated synchrony. Together, our results show that prefrontal-hippocampal theta synchronization leads to a higher probability of a correct choice and strengthens prefrontal-thalamic dialogue. Our findings reveal new insights into the neural circuit dynamics underlying memory-guided choices and highlight a promising technique to potentiate cognitive processes or behavior via brain machine interfacing.

A Yet Unrealized Promise: Structured Advance Care Planning Elements in the Electronic Health Record

Background: Electronic health records (EHRs) may help enable reliable, rapid data management for many uses, such as facilitating communication of advance care planning (ACP). However, issues with validity and accuracy of EHRs hinder the use of ACP information for practical applications. Design: We present a cross-sectional pilot study of 433 older adults with cancer from three large health care systems, participating in an ongoing multisite pragmatic trial (4UH3AG060626-02). We compared data extracted from dedicated structured EHR fields for ACP to a chart review of corresponding ACP documentation contained in the medical chart. Results: Structured ACP data existed for 43.2% of patients and varied by site (25.7% -48.9%). Of the identified structured ACP data elements, 59.2% of recorded elements were correct, 23.7% were incorrect, and 17.1% were duplicates with heterogeneity across sites. Conclusion: Structured ACP data in EHRs were frequently incorrect. This represents a problem for patients and their families, as well as quality improvement and research efforts. Clinical Trials Registration: NCT03609177.

Incidence of Hypocapnia, Hypercapnia, and Acidosis and the Associated Risk of Adverse Events in Preterm Neonates

BACKGROUND

Permissive hypercapnia is a lung-protection strategy. We sought to review our current clinical practice for the range of permissive hypercapnia and identify the relationship between P_aCO2 and pH and adverse outcomes.

METHODS

A secondary analysis of a delayed cord-clamping clinical trial was performed on all arterial blood gas tests in the first 72 h in infants < 32 weeks gestational age. All arterial blood gas values were categorized into a clinical range to determine the percent likelihood of occurring in the total sample. The univariate and multivariate relationships of severe adverse events and the time-weighted P_aCO2 , fluctuation of P_aCO2 , maximal and minimal P_aCO2 , base excess, and pH were assessed.

RESULTS

147 infants with birthweight of 1,206 ± 395 g and gestational age of 28 ± 2 weeks were included. Of the 1,316 total samples, < 2% had hypocapnia (P_aCO2 <30 mm Hg), 47% were normocapnic (P_aCO2 35-45 mm Hg), 26.5% had mild hypercapnia (P_aCO2 45-55 mm Hg), 13% had moderate hypercapnia (P_aCO2 55-65 mm Hg), and 6.5% had severe hypercapnia (P_aCO2 ≥ 65 mm Hg). There were no adverse events associated with hypocapnia. Subjects with death/severe intraventricular hemorrhage had a higher mean P_aCO2 of 52.3 versus 44.7 (odds ratio [OR] 1.16, 95% CI 1.04-1.29, P = .006), higher variability of P_aCO2 with a standard deviation of 12.6 versus 7.8 (OR 1.15, 95% CI 1.03-1.27, P = .01), and a lower minimum pH of 7.03 versus 7.23 (OR 0, 95% CI 0-0.06, P = .003). There was no significant difference in any variables in subjects who developed other adverse events.

CONCLUSION

The routine targeting of higher than normal P_aCO2 goals may lead to a low incidence of hypocapnia and associated adverse events. Hypercapnia is common, and moderate hypercapnia may increase the risk of neurologic injury and provide little pulmonary benefit.

Expanded distribution of an investigational drug in parallel with ongoing controlled clinical trials: the didanosine model

The purpose of the didanosine Expanded Access Program was to provide a needed antiretroviral agent to individuals who were unable to tolerate other therapy for human immunodeficiency virus infection or in whom such therapy was failing. The logistics of establishing this program are described, and the results of on-site auditing that confirmed the validity of the data obtained through this program are presented.

An evaluation of the susceptibility patterns of gram-negative organisms isolated in cancer centres with aminoglycoside usage

This study in 12 cancer treatment centres across the United States was designed to evaluate the potential for increased resistance to amikacin with unrestricted use. An initial 3-month baseline period during which the use of amikacin was restricted and that of tobramycin and gentamicin unrestricted was followed by a period of at least 12 months when amikacin was the primary aminoglycoside. Resistance of Gram-negative bacilli to these aminoglycosides from hospitalized patients was monitored and compared for the two periods. Amikacin usage increased from a mean of 20.1% to a mean of 83.9% of aminoglycoside patient-days. A reduction in the use of tobramycin and gentamicin were observed with means of 66.1 and 10%, and 13.9 and 6.1%, respectively for the two periods. Resistance to amikacin was 0.85% at baseline and 1.3% at end-point which was not clinically significant (P = 0.614). Baseline resistance was 6.5 and 7.6%, while final resistance was 2.6 and 4.8%, respectively for tobramycin (P = 0.001) and gentamicin (P = 0.052).