Daily Anesthesiology Research Analysis

Chronic pain is a complex clinical problem comprising multiple conditions that may share a common genetic profile. Genome-wide association studies (GWAS) have identified many risk loci whose cell-type context remains unclear. Here, we integrated GWAS data on chronic pain (N = 1,235,695) with single-cell RNA sequencing (scRNA-seq) data from human brain and dorsal root ganglia (hDRG), and single-cell chromatin accessibility data from human brain and mouse dorsal horn. Pain-associated variants were enriched in glutamatergic neurons; mainly in prefrontal cortex, hippocampal CA1-3, and amygdala. In hDRG, the hPEP.TRPV1/A1.2 neuronal subtype showed robust enrichment. Chromatin accessibility analyses revealed variant enrichment in excitatory and inhibitory neocortical neurons in brain and in midventral neurons and oligodendrocyte precursor cells in the mouse dorsal horn. Gene-level heritability in the brain highlighted roles for kinase activity, GABAergic synapses, axon guidance, and neuron projection development. In hDRG, implicated genes related to glutamatergic signaling and neuronal projection. In cervical DRG of patients with acute or chronic pain (N = 12), scRNA-seq data from neuronal or non-neuronal cells were enriched for chronic pain-associated genes (e.g., EFNB2, GABBR1, NCAM1, SCN11A). This cell-type-specific genetic architecture of chronic pain across central and peripheral nervous system circuits provides a foundation for targeted translational research.

BACKGROUND: Perioperative hyperoxia may be associated with increased long-term mortality, whereas perioperative antioxidants may be associated with reduced long-term mortality. This study aimed to determine if high perioperative inspiratory oxygen fraction (FiO METHODS: This was the preplanned 1-year follow-up of 600 patients with cardiovascular risk factors, scheduled for noncardiac surgery. They were randomized in a 2 × 2 factorial design to perioperative FiO RESULTS: Follow-up was completed for 594 patients (99%). Twenty-five of 298 patients (8.4%) allocated to FiO CONCLUSIONS: Differences in all-cause mortality, hospital admission, or MI were not statistically significant at 1-year follow-up for either oxygen fractions or antioxidant administration in patients undergoing major noncardiac surgery. EDITORIAL COMMENT: In this preplanned long-term study of the VIXIE trial, no differences in total mortality, hospitalization, or myocardial infarction were found for oxygen fractions of 0.80 compared to 0.30 or antioxidant administration compared to placebo. Interestingly, the study showed a higher rate of fatalities with 80% oxygen which appeared only to be present in patients not given the antioxidant intervention, but this is hypothesis-generating and needs to be further investigated in new clinical trials. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03494387.

It has been demonstrated that patient-specific intracranial pressure (ICP) thresholds are possible to derive using the function intersectionality between ICP and cerebrovascular reactivity (CVR). Such individualized ICP (iICP) thresholds represent a potential personalized medicine approach to neurocritical care management. However, it is currently unknown how various CVR thresholds compare in regard to deriving iICP. Here we attempt to identify the CVR thresholds that are best suited for iICP derivation. Leveraging 365 patient data sets from the CAnadian High-Resolution TBI (CAHR-TBI) Research Collaborative, iICP was derived using three ICP-based CVR indices: the pressure reactivity index (PRx); the pulse amplitude index (PAx); and the RAC index, and thresholds ranging from - 1 to + 1, in 0.05 increments. Patients were dichotomized based on 6-month outcome scores into Alive vs. Dead and Favorable vs. Unfavorable outcome. 2 × 2 tables were created for each threshold, grouping patients by outcome and whether their mean ICP was greater or less than their calculated iICP. Chi-squares were calculated for each table and subsequently plotted. The thresholds that produced the largest Chi-square values were identified as those able to derive the iICP with the greatest ability to predict outcomes. Next, Spearman rank correlation testing was used to evaluate associations between iICP, for each threshold, and measures of cerebral physiologic insult burden. With consideration of yield data, ability to predict outcome, and association with cerebral physiologic insult burden, a threshold of + 0.05 was identified for PRx. No optimal threshold could be identified for PAx or RAC.