High-dimensional single-cell analysis of human natural killer cell heterogeneity.

Natural killer (NK) cells are innate lymphoid cells (ILCs) contributing to immune responses to microbes and tumors. Historically, their classification hinged on a limited array of surface protein markers. Here, we used single-cell RNA sequencing (scRNA-seq) and cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) to dissect the heterogeneity of NK cells. We identified three prominent NK cell subsets in healthy human blood: NK1, NK2 and NK3, further differentiated into six distinct subgroups. Our findings delineate the molecular characteristics, key transcription factors, biological functions, metabolic traits and cytokine responses of each subgroup. These data also suggest two separate ontogenetic origins for NK cells, leading to divergent transcriptional trajectories. Furthermore, we analyzed the distribution of NK cell subsets in the lung, tonsils and intraepithelial lymphocytes isolated from healthy individuals and in 22 tumor types. This standardized terminology aims at fostering clarity and consistency in future research, thereby improving cross-study comparisons.

Antagonistic Inflammatory Phenotypes Dictate Tumor Fate and Response to Immune Checkpoint Blockade.

Inflammation can support or restrain cancer progression and the response to therapy. Here, we searched for primary regulators of cancer-inhibitory inflammation through deep profiling of inflammatory tumor microenvironments (TMEs) linked to immune-dependent control in mice. We found that early intratumoral accumulation of interferon gamma (IFN-γ)-producing natural killer (NK) cells induced a profound remodeling of the TME and unleashed cytotoxic T cell (CTL)-mediated tumor eradication. Mechanistically, tumor-derived prostaglandin E2 (PGE2) acted selectively on EP2 and EP4 receptors on NK cells, hampered the TME switch, and enabled immune evasion. Analysis of patient datasets across human cancers revealed distinct inflammatory TME phenotypes resembling those associated with cancer immune control versus escape in mice. This allowed us to generate a gene-expression signature that integrated opposing inflammatory factors and predicted patient survival and response to immune checkpoint blockade. Our findings identify features of the tumor inflammatory milieu associated with immune control of cancer and establish a strategy to predict immunotherapy outcomes.

Fatty acid oxidation fuels natural killer cell responses against infection and cancer.

Natural killer (NK) cells are a vital part of the innate immune system capable of rapidly clearing mutated or infected cells from the body and promoting an immune response. Here, we find that NK cells activated by viral infection or tumor challenge increase uptake of fatty acids and their expression of carnitine palmitoyltransferase I (CPT1A), a critical enzyme for long-chain fatty acid oxidation. Using a mouse model with an NK cell-specific deletion of CPT1A, combined with stable 13C isotope tracing, we observe reduced mitochondrial function and fatty acid-derived aspartate production in CPT1A-deficient NK cells. Furthermore, CPT1A-deficient NK cells show reduced proliferation after viral infection and diminished protection against cancer due to impaired actin cytoskeleton rearrangement. Together, our findings highlight that fatty acid oxidation promotes NK cell metabolic resilience, processes that can be optimized in NK cell-based immunotherapies.

Prostaglandin E2 impacts multiple stages of the natural killer cell antitumor immune response.

Tumor immune escape is a major factor contributing to cancer progression and unresponsiveness to cancer therapies. Tumors can produce prostaglandin E2 (PGE2 ), an inflammatory mediator that directly acts on Natural killer (NK) cells to inhibit antitumor immunity. However, precisely how PGE2 influences NK cell tumor-restraining functions remains unclear. Here, we report that following PGE2 treatment, human NK cells exhibited altered expression of specific activating receptors and a reduced ability to degranulate and kill cancer targets. Transcriptional analysis uncovered that PGE2 also differentially modulated the expression of chemokine receptors by NK cells, inhibiting CXCR3 but increasing CXCR4. Consistent with this, PGE2-treated NK cells exhibited decreased migration to CXCL10 but increased ability to migrate toward CXCL12. Using live cell imaging, we showed that in the presence of PGE2 , NK cells were slower and less likely to kill cancer target cells following conjugation. Imaging the sequential stages of NK cell killing revealed that PGE2 impaired NK cell polarization, but not the re-organization of synaptic actin or the release of perforin itself. Together, these findings demonstrate that PGE2 affects multiple but select NK cell functions. Understanding how cancer cells subvert NK cells is necessary to more effectively harness the cancer-inhibitory function of NK cells in treatments.

Ablation of placental REST deregulates fetal brain metabolism and impacts gene expression of the offspring brain at the postnatal and adult stages.

In this study, the transcriptional repressor REST (Repressor Element 1 Silencing Transcription factor) was ablated in the mouse placenta to investigate molecular and cellular impacts on the offspring brain at different life stages. Ablation of placental REST deregulated several brain metabolites, including glucose and lactate that fuel brain energy, vitamin C (ascorbic acid) that functions in the epigenetic programming of the brain during postnatal development, and glutamate and creatine that help the brain to respond to stress conditions during adult life. Bulk RNA-seq analysis showed that a lack of placental REST persistently altered multiple transport genes, including those related to oxygen transportation in the offspring brain. While metabolic genes were impacted in the postnatal brain, different stress response genes were activated in the adult brain. DNA methylation was also impacted in the adult brain due to the loss of placental REST, but in a sex-biased manner. Single-nuclei RNA-seq analysis showed that specific cell types of the brain, particularly those of the choroid plexus and ependyma, which play critical roles in producing cerebrospinal fluid and maintaining metabolic homeostasis, were significantly impacted due to the loss of placental REST. These cells showed significant differential expression of genes associated with the metabotropic (G coupled protein) and ionotropic (ligand-gated ion channel) glutamate receptors, suggesting an impact of ablation of placental REST on the glutamatergic signaling of the offspring brain. The study expands our understanding of placental influences on the offspring brain.

Radiotherapy transiently reduces the sensitivity of cancer cells to lymphocyte cytotoxicity.

The impact of radiotherapy on the interaction between immune cells and cancer cells is important not least because radiotherapy can be used alongside immunotherapy as a cancer treatment. Unexpectedly, we found that X-ray irradiation of cancer cells induced significant resistance to natural killer (NK) cell killing. This was true across a wide variety of cancer-cell types as well as for antibody-dependent cellular cytotoxicity. Resistance appeared 72 h postirradiation and persisted for 2 wk. Resistance could also occur independently of radiotherapy through pharmacologically induced cell-cycle arrest. Crucially, multiple steps in NK-cell engagement, synapse assembly, and activation were unaffected by target cell irradiation. Instead, radiotherapy caused profound resistance to perforin-induced calcium flux and lysis. Resistance also occurred to a structurally similar bacterial toxin, streptolysin O. Radiotherapy did not affect the binding of pore-forming proteins at the cell surface or membrane repair. Rather, irradiation instigated a defect in functional pore formation, consistent with phosphatidylserine-mediated perforin inhibition. In vivo, radiotherapy also led to a significant reduction in NK cell-mediated clearance of cancer cells. Radiotherapy-induced resistance to perforin also constrained chimeric antigen receptor T-cell cytotoxicity. Together, these data establish a treatment-induced resistance to lymphocyte cytotoxicity that is important to consider in the design of radiotherapy-immunotherapy protocols.

The Ighmbp2D564N mouse model is the first SMARD1 model to demonstrate respiratory defects.

Spinal muscular atrophy with respiratory distress type I (SMARD1) is a neurodegenerative disease defined by respiratory distress, muscle atrophy and sensory and autonomic nervous system defects. SMARD1 is a result of mutations within the IGHMBP2 gene. We have generated six Ighmbp2 mouse models based on patient-derived mutations that result in SMARD1 and/or Charcot-Marie Tooth Type 2 (CMT2S). Here we describe the characterization of one of these models, Ighmbp2D564N (human D565N). The Ighmbp2D564N/D564N mouse model mimics important aspects of the SMARD1 disease phenotype, including motor neuron degeneration and muscle atrophy. Ighmbp2D564N/D564N is the first SMARD1 mouse model to demonstrate respiratory defects based on quantified plethysmography analyses. SMARD1 disease phenotypes, including the respiratory defects, are significantly diminished by intracerebroventricular (ICV) injection of ssAAV9-IGHMBP2 and the extent of phenotypic restoration is dose-dependent. Collectively, this model provides important biological insight into SMARD1 disease development.

Society of Critical Care Medicine Guidelines on Recognizing and Responding to Clinical Deterioration Outside the ICU: 2023.

RATIONALE: Clinical deterioration of patients hospitalized outside the ICU is a source of potentially reversible morbidity and mortality. To address this, some acute care hospitals have implemented systems aimed at detecting and responding to such patients. OBJECTIVES: To provide evidence-based recommendations for hospital clinicians and administrators to optimize recognition and response to clinical deterioration in non-ICU patients. PANEL DESIGN: The 25-member panel included representatives from medicine, nursing, respiratory therapy, pharmacy, patient/family partners, and clinician-methodologists with expertise in developing evidence-based Clinical Practice Guidelines. METHODS: We generated actionable questions using the Population, Intervention, Control, and Outcomes (PICO) format and performed a systematic review of the literature to identify and synthesize the best available evidence. We used the Grading of Recommendations Assessment, Development, and Evaluation Approach to determine certainty in the evidence and to formulate recommendations and good practice statements (GPSs). RESULTS: The panel issued 10 statements on recognizing and responding to non-ICU patients with critical illness. Healthcare personnel and institutions should ensure that all vital sign acquisition is timely and accurate (GPS). We make no recommendation on the use of continuous vital sign monitoring among unselected patients. We suggest focused education for bedside clinicians in signs of clinical deterioration, and we also suggest that patient/family/care partners' concerns be included in decisions to obtain additional opinions and help (both conditional recommendations). We recommend hospital-wide deployment of a rapid response team or medical emergency team (RRT/MET) with explicit activation criteria (strong recommendation). We make no recommendation about RRT/MET professional composition or inclusion of palliative care members on the responding team but suggest that the skill set of responders should include eliciting patients' goals of care (conditional recommendation). Finally, quality improvement processes should be part of a rapid response system. CONCLUSIONS: The panel provided guidance to inform clinicians and administrators on effective processes to improve the care of patients at-risk for developing critical illness outside the ICU.

Executive Summary: Society of Critical Care Medicine Guidelines on Recognizing and Responding to Clinical Deterioration Outside the ICU.

RATIONALE: Clinical deterioration of patients hospitalized outside the ICU is a source of potentially reversible morbidity and mortality. To address this, some acute care facilities have implemented systems aimed at detecting and responding to such patients. OBJECTIVES: To provide evidence-based recommendations for hospital clinicians and administrators to optimize recognition and response to clinical deterioration in non-ICU patients. PANEL DESIGN: The 25-member panel included representatives from medicine, nursing, respiratory therapy, pharmacy, patient/family partners, and clinician-methodologists with expertise in developing evidence-based clinical practice guidelines. METHODS: We generated actionable questions using the Population, Intervention, Control, and Outcomes format and performed a systematic review of the literature to identify and synthesize the best available evidence. We used the Grading of Recommendations Assessment, Development, and Evaluation approach to determine certainty in the evidence and to formulate recommendations and good practice statements (GPSs). RESULTS: The panel issued 10 statements on recognizing and responding to non-ICU patients with critical illness. Healthcare personnel and institutions should ensure that all vital sign acquisition is timely and accurate (GPS). We make no recommendation on the use of continuous vital sign monitoring among "unselected" patients due to the absence of data regarding the benefit and the potential harms of false positive alarms, the risk of alarm fatigue, and cost. We suggest focused education for bedside clinicians in signs of clinical deterioration, and we also suggest that patient/family/care partners' concerns be included in decisions to obtain additional opinions and help (both conditional recommendations). We recommend hospital-wide deployment of a rapid response team or medical emergency team (RRT/MET) with explicit activation criteria (strong recommendation). We make no recommendation about RRT/MET professional composition or inclusion of palliative care members on the responding team but suggest that the skill set of responders should include eliciting patients' goals of care (conditional recommendation). Finally, quality improvement processes should be part of a rapid response system (GPS). CONCLUSIONS: The panel provided guidance to inform clinicians and administrators on effective processes to improve the care of patients at-risk for developing critical illness outside the ICU.

SARS-CoV-2 infection perturbs enhancer mediated transcriptional regulation of key pathways.

Despite extensive studies on the effects of SARS-CoV-2 infection, there is still a lack of understanding of the downstream epigenetic and regulatory alterations in infected cells. In this study, we investigated changes in enhancer acetylation in epithelial lung cells infected with SARS-CoV-2 and their influence on transcriptional regulation and pathway activity. To achieve this, we integrated and reanalyzed data of enhancer acetylation, ex-vivo infection and single cell RNA-seq data from human patients. Our findings revealed coordinated changes in enhancers and transcriptional networks. We found that infected cells lose the WT1 transcription factor and demonstrate disruption of WT1-bound enhancers and of their associated target genes. Downstream targets of WT1 are involved in the regulation of the Wnt signaling and the mitogen-activated protein kinase cascade, which indeed exhibit increased activation levels. These findings may provide a potential explanation for the development of pulmonary fibrosis, a lethal complication of COVID-19. Moreover, we revealed over-acetylated enhancers associated with upregulated genes involved in cell adhesion, which could contribute to cell-cell infection of SARS-CoV-2. Furthermore, we demonstrated that enhancers may play a role in the activation of pro-inflammatory cytokines and contribute to excessive inflammation in the lungs, a typical complication of COVID-19. Overall, our analysis provided novel insights into the cell-autonomous dysregulation of enhancer regulation caused by SARS-CoV-2 infection, a step on the path to a deeper molecular understanding of the disease.

Updating the study protocol: Insight 46 - a longitudinal neuroscience sub-study of the MRC National Survey of Health and Development - phases 2 and 3.

BACKGROUND: Although age is the biggest known risk factor for dementia, there remains uncertainty about other factors over the life course that contribute to a person's risk for cognitive decline later in life. Furthermore, the pathological processes leading to dementia are not fully understood. The main goals of Insight 46-a multi-phase longitudinal observational study-are to collect detailed cognitive, neurological, physical, cardiovascular, and sensory data; to combine those data with genetic and life-course information collected from the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort); and thereby contribute to a better understanding of healthy ageing and dementia. METHODS/DESIGN: Phase 1 of Insight 46 (2015-2018) involved the recruitment of 502 members of the NSHD (median age = 70.7 years; 49% female) and has been described in detail by Lane and Parker et al. 2017. The present paper describes phase 2 (2018-2021) and phase 3 (2021-ongoing). Of the 502 phase 1 study members who were invited to a phase 2 research visit, 413 were willing to return for a clinic visit in London and 29 participated in a remote research assessment due to COVID-19 restrictions. Phase 3 aims to recruit 250 study members who previously participated in both phases 1 and 2 of Insight 46 (providing a third data time point) and 500 additional members of the NSHD who have not previously participated in Insight 46. DISCUSSION: The NSHD is the oldest and longest continuously running British birth cohort. Members of the NSHD are now at a critical point in their lives for us to investigate successful ageing and key age-related brain morbidities. Data collected from Insight 46 have the potential to greatly contribute to and impact the field of healthy ageing and dementia by combining unique life course data with longitudinal multiparametric clinical, imaging, and biomarker measurements. Further protocol enhancements are planned, including in-home sleep measurements and the engagement of participants through remote online cognitive testing. Data collected are and will continue to be made available to the scientific community.

Extremes of baseline cognitive function determine the severity of delirium: a population study.

Although delirium is a significant clinical and public health problem, little is understood about how specific vulnerabilities underlie the severity of its presentation. Our objective was to quantify the relationship between baseline cognition and subsequent delirium severity. We prospectively investigated a population-representative sample of 1510 individuals aged ≥70 years, of whom 209 (13.6%) were hospitalized across 371 episodes (1999 person-days assessment). Baseline cognitive function was assessed using the modified Telephone Interview for Cognitive Status, supplemented by verbal fluency measures. We estimated the relationship between baseline cognition and delirium severity [Memorial Delirium Assessment Scale (MDAS)] and abnormal arousal (Observational Scale of Level of Arousal), adjusted by age, sex, frailty and illness severity. We conducted further analyses examining presentations to specific hospital settings and common precipitating aetiologies. The median time from baseline cognitive assessment to admission was 289 days (interquartile range 130 to 47 days). In admitted patients, delirium was present on at least 1 day in 45% of admission episodes. The average number of days with delirium (consecutively positive assessments) was 3.9 days. Elective admissions accounted for 88 bed days (4.4%). In emergency (but not elective) admissions, we found a non-linear U-shaped relationship between baseline global cognition and delirium severity using restricted cubic splines. Participants with baseline cognition 2 standard deviations below average (z-score = -2) had a mean MDAS score of 14 points (95% CI 10 to 19). Similarly, those with baseline cognition z-score = + 2 had a mean MDAS score of 7.9 points (95% CI 4.9 to 11). Individuals with average baseline cognition had the lowest MDAS scores. The association between baseline cognition and abnormal arousal followed a comparable pattern. C-reactive protein ≥20 mg/l and serum sodium <125 mM/l were associated with more severe delirium. Baseline cognition is a critical determinant of the severity of delirium and associated changes in arousal. Emergency admissions with lowest and highest baseline cognition who develop delirium should receive enhanced clinical attention.

Drug-induced orthostatic hypotension: Cluster analysis of co-prescription patterns in older people in UK primary care.

PURPOSE: Over 250 medications are reported to cause orthostatic hypotension, associated with serious adverse outcomes in older adults. Studies suggest a harmful cumulative risk of orthostatic hypotension with multiple medication use. However, there is limited evidence on the potential for harm in practice, particularly which drugs is co-prescribed and may increase risk of orthostatic hypotension. METHODS: Retrospective cohort study and cluster analysis using general practice data from IQVIA Medical Research Data (IMRD) in patients aged ≥50 contributing data between 1 January 2018 and 31 December 2018. Thirteen drug groups known to be associated with orthostatic hypotension by mechanism, were analyzed and clusters generated by sex and age-band. RESULTS: A total of 602 713 individuals aged ≥50 with 283 912 (47%) men and 318 801 (53%) women were included. The most prevalent prescriptions that might contribute to orthostatic hypotension were ACE inhibitors, calcium-channel blockers, beta-blockers, selective serotonin reuptake inhibitors and uroselective alpha-blockers. We identified distinct clusters of cardiovascular system (cardiovascular system) drugs in men and women at all ages. cardiovascular system plus psychoactive drug clusters were common in women at all ages, and in men aged ≤70. cardiovascular system plus uroselective alpha-blockers were identified in men aged ≥70. CONCLUSIONS: Distinct clusters of drugs associated with orthostatic hypotension exist in practice, which change over the life course. Our findings highlight potentially harmful drug combinations that may cause cumulative risk of orthostatic hypotension in older people. This may guide clinicians about the potential of synergistic harm and to monitor for orthostatic hypotension if using combinations of cardiovascular system drugs, cardiovascular system plus psychoactive drugs and/or alpha-blockers-particularly in patients aged ≥70 or at high-risk due to comorbidity. Future research should consider quantifying the risk of drug-induced orthostatic hypotension with such drug combinations.

Delirium is more common and associated with worse outcomes in Parkinson's disease compared to older adult controls: results of two prospective longitudinal cohort studies.

BACKGROUND: Inpatient prevalence of Parkinson's disease (PD) delirium varies widely across the literature. Delirium in general older populations is associated with adverse outcomes, such as increased mortality, dementia, and institutionalisation. However, to date there are no comprehensive prospective studies in PD delirium. This study aimed to determine delirium prevalence in hospitalised PD participants and the association with adverse outcomes, compared to a control group of older adults without PD. METHODS: Participants were hospitalised inpatients from the 'Defining Delirium and its Impact in Parkinson's Disease' and the 'Delirium and Cognitive Impact in Dementia' studies comprising 121 PD participants and 199 older adult controls. Delirium was diagnosed prospectively using the Diagnostic and Statistical Manual of Mental Disorders 5th Edition criteria. Outcomes were determined by medical note reviews and/or home visits 12 months post hospital discharge. RESULTS: Delirium was identified in 66.9% of PD participants compared to 38.7% of controls (p < 0.001). In PD participants only, delirium was associated with a significantly higher risk of mortality (HR = 3.3 (95% confidence interval [CI] = 1.3-8.6), p = 0.014) and institutionalisation (OR = 10.7 (95% CI = 2.1-54.6), p = 0.004) 12 months post-discharge, compared to older adult controls. However, delirium was associated with an increased risk of developing dementia 12 months post-discharge in both PD participants (OR = 6.1 (95% CI = 1.3-29.5), p = 0.024) and in controls (OR = 13.4 (95% CI = 2.5-72.6), p = 0.003). CONCLUSION: Delirium is common in hospitalised PD patients, affecting two thirds of patients, and is associated with increased mortality, institutionalisation, and dementia. Further research is essential to understand how to accurately identify, prevent and manage delirium in people with PD who are in hospital.

Factors associated with self-rated health in people with late-stage parkinson's and cognitive impairment.

PURPOSE: To investigate the contributors to self-rated health in people with late-stage Parkinson's disease (PD) and cognitive impairment. METHODS: A secondary analysis of baseline data from the international Care of Late-Stage Parkinsonism (CLaSP) cohort study was conducted. Participants with PD and either dementia or mild cognitive impairment or MMSE < 24/30 in the absence of major depression were included if they had completed the EQ-5D-3L assessment (n = 277). Factors associated with self-rated health (EQ-5D-3L Index and Visual Analogue Scale) were investigated through multivariable linear regression. RESULTS: More severe PD (motor and non-motor) was associated with worse self-rated health. The EQ-5D-3L dimensions of Mobility, Self-Care and Usual Activities were almost universally affected; the latter two particularly severely. Being unable to perform usual activities or having moderate to extreme anxiety or depression were significantly associated with EQ-5D-3L Visual Analogue Scale, suggesting these are particularly valued. Worse motor impairment and function and the non-motor symptom domains of mood, perception, sexual function, and miscellaneous (e.g., pain) were associated with worse self-rated health, whereas greater burden of gastrointestinal symptoms was associated with better self-rated health in multivariate analysis. Better self-rated health was associated with recent PD nurse consultation, and higher doses of dopaminergic medication. CONCLUSION: Improvement of activities of daily living, mood and anxiety should be prioritised in clinical practice, with consideration of perception and sexual function in this population. Recent nurse consultations and higher antiparkinsonian doses are associated with better self-rated health, suggesting there is no room for a therapeutic nihilism in this population of people within a complex phase of PD.

Chest Decompressions - The Driver of CPR Efficacy: Exploring the Relationship Between Compression Rate, Depth, Recoil Velocity, and End-Tidal CO2.

OBJECTIVE: Cardiopulmonary arrest survival is dependent on optimization of perfusion via high quality cardiopulmonary resuscitation (CPR), defined by a complex dynamic between rate, depth, and recoil velocity. Here we explore the interaction between these metrics and create a model that explores the impact of these variables on compression efficacy. METHODS: This study was performed in a large urban/suburban fire-based emergency medical services (EMS) system over a nine-month period from 2019 to 2020. Manual chest compression parameters [rate/depth/recoil velocity] from a cohort of out-of-hospital cardiac arrest (OOHCA) victims were abstracted from monitor defibrillators (ZOLL X-series) and end-tidal carbon dioxide (ETCO2) from sensors. The mean values of these parameters were modeled against each other using multiple regression and structural equation modeling with ETCO2 as a dependent variable. RESULTS: Data from a total of 335 patients were analyzed. Strong linear relationships were observed between compression depth/recoil velocity (r = .87, p < .001), ETCO2/depth (r = .23, p < .001) and ETCO2/recoil velocity (r = .61, p < .001). Parabolic relationships were observed between rate/depth (r = .39, p < .001), rate/recoil velocity (r = .26, p < .001), and ETCO2/rate (r = .20, p = .003). Rate, depth, and recoil velocity were modeled as independent variables and ETCO2 as a dependent variable with excellence model performance suggesting the primary driver of stroke volume to be recoil velocity rather than compression depth. CONCLUSIONS: We used manual CPR metrics from out of hospital cardiac arrests to model the relationship between CPR metrics. These results consistently support the importance of chest recoil on CPR hemodynamics, suggesting that guidelines for optimal CPR should emphasize the importance of maximum chest recoil.

Surgeon Factors and Trends Associated With the Use of Subacromial Decompression at the Time of Rotator Cuff Repair.

PURPOSE: Subacromial decompression (SAD) has historically been described as an essential part of the surgical treatment of rotator cuff disorders. However, investigations throughout the 21st century have increasingly questioned the need for routine SAD during rotator cuff repair (RCR). Our purpose was to assess for changes in the incidence of SAD performed during RCR over a 12-year period. In addition, we aimed to characterize surgeon and practice factors associated with SAD use. METHODS: Records from two large tertiary referral systems in the United States from 2010 to 2021 were reviewed. All cases of RCR with and without SAD were identified. The outcome of interest was the proportion of SAD performed during RCR across years and by surgeon. Surgeon-specific characteristics included institution, fellowship training, surgical volume, academic practice, and years in practice. Yearly trends were assessed using binomial logistic regression modeling, with a random effect accounting for surgeon-specific variability. RESULTS: During the study period, 37,165 RCR surgeries were performed by 104 surgeons. Of these cases, 71% underwent SAD during RCR. SAD use decreased by 11%. The multivariable model found that surgeons in academic practice, those with lower surgical volume, and those with increasing years in practice were significantly associated with increased odds of performing SAD. Surgeons with fellowship training were significantly more likely to use SAD over time, with the greatest odds of SAD noted for sports medicine surgeons (odds ratio = 3.04). CONCLUSIONS: Although SAD use during RCR appears to be decreasing, multiple surgeon and practice factors (years in practice, fellowship training, volume, and academic practice) are associated with a change in SAD use. CLINICAL RELEVANCE: These data suggest that early-career surgeons entering practice are likely driving the trend of declining SAD. Despite evidence suggesting limited clinical benefits, SAD remains commonly performed; future studies should endeavor to determine factors associated with practice changes among surgeons.

The impact of preoperative benzodiazepine use on postoperative opioid use in total shoulder arthroplasty.

BACKGROUND: As the rate of total shoulder arthroplasty (TSA) and preoperative benzodiazepine use rise, there is an increased need to understand the impact of preoperative benzodiazepine use on postoperative opioid consumption following TSA, especially amid the current opioid epidemic. The relationship between preoperative benzodiazepine use and chronic opioid use postoperatively has been well described following other orthopedic procedures; however, the impact on patients undergoing TSA remains unclear. This study aims to identify the impact of preoperative benzodiazepine use on opioid use following TSA. METHODS: A retrospective chart review of 4488 patients undergoing primary TSA (Current Procedural Terminology code 23472) at a single institution from 2014 to 2022 was performed. Patient demographics, surgical variables, comorbidities, Distressed Communities Index (DCI), and clinical outcomes, including readmission and revision, were collected. The Charlson Comorbidity Index (CCI) was used to assess preoperative health status. Opioid use in morphine milligram equivalents (MMEs) and benzodiazepine use were also recorded using the Prescription Drug Monitoring Program Database. Opioid use was collected at 30-, 60-, and 90-day intervals both before and after each patient's date of surgery. Statistical analysis included stepwise logistic regression to identify variables independently affecting benzodiazepine use pre- and postoperatively. RESULTS: Overall, 16% of patients used benzodiazepines within 90 days before their date of surgery. Of those patients, 46.4% were also using preoperative opioids, compared with just 30.0% of patients who were benzodiazepine-naïve (P < .001). Preoperative benzodiazepine use was also associated with increased pre- and postoperative total opioid use in MMEs and the number of opioid prescriptions across all time points when compared to benzodiazepine-naïve patients (P < .001). Furthermore, 37.4% of preoperative benzodiazepine users went on to prolonged opioid use (filled prescriptions >30 days after surgery) compared to 19.0% of those who were benzodiazepine-naïve (P < .001). CONCLUSION: This study demonstrates a significant association between preoperative benzodiazepine use and increased and prolonged opioid use following TSA. Further exploration of risk factors contributing to preoperative benzodiazepine use may help to reduce overall opioid use in patients undergoing TSA.

Effects of Socioeconomic Burden on Opioid Use Following Total Shoulder Arthroplasty.

BACKGROUND: Preoperative opioid users (POU) experience worse outcomes and higher complication rates compared to opioid naïve patients (ONP) following shoulder arthroplasty. This study evaluates the effects of socioeconomic status (SES), as measured by the distressed communities index (DCI), on pre- and postoperative opioid use and its influence on clinical outcomes such as readmission and revision surgery. METHODS: A retrospective review of patients who underwent primary shoulder arthroplasty (CPT code 23472) from 2014-2022 at a single academic institution was performed. Exclusion criteria included arthroplasty for fracture, active malignancy, and revision arthroplasty. Demographics, Charlson Comorbidity Index (CCI), DCI, and clinical outcomes including 90-day readmission and revision surgery were collected. Patients were classified according to the DCI score of their zip code. Using the Prescription Drug Monitoring Program database, patient pre- and postoperative opioid use in morphine milligram equivalents (MME) was gathered. RESULTS: Individuals from distressed communities utilized more opioids within 90 days preoperatively compared to patients from prosperous, comfortable, mid-tier, and at-risk populations respectively. Patients from distressed communities also used significantly more opioids within 90 days postoperatively compared to prosperous, comfortable, and mid-tier respectively. Of patients from distressed communities, 35.1% developed prolonged opioid use (filling prescriptions >30 days after surgery), significantly more than all other cohorts. Among all patients, 3.5% were readmitted within 90 days and were more likely to be prolonged opioid users (38.9 vs 21.3%, p<0.001). Similarly, 1.5% of patients underwent revision surgery. Those who underwent revision were significantly more likely to be prolonged opioid users (38.2 vs 21.7%, p=0.002). CONCLUSIONS: Shoulder arthroplasty patients from distressed communities use more opioids within 90 days before and after their surgery and are more likely to become prolonged opioid users placing them at risk for readmission and revision surgery. Identifying patients at an increased risk for excess opioid use is essential to employ appropriate strategies that minimize the detrimental effects of prolonged use following surgery.

A Descriptive Analysis of Air Medical Pediatric Rapid Sequence Intubation: Successes and Opportunities.

OBJECTIVE: Advanced airway management, including the use of rapid sequence intubation (RSI), is fundamental in resuscitation. However, the reported experience with pediatric airway management is limited because of the relatively low number of emergency RSI procedures in children. The aim of this study was to document the experience with pediatric RSI in a large air medical database and explore opportunities for improvement. METHODS: All pediatric patients (age < 18 years) undergoing RSI by air medical crews between 2015 and 2019 were included in this analysis. Subjects were divided a priori into 3 age subgroups (0-2 years, 3-8 years, and 9-17 years). The primary variables of interest included overall intubation success, first-attempt intubation success, and first-attempt intubation success without desaturation. The rates of positive-pressure ventilation (PPV) use for preoxygenation and oxygen desaturation were also explored. RESULTS: A total of 1,091 pediatric RSI patients were included. The overall intubation success rate was 98% (0-2 years = 96%, 3-8 years = 97%, and 9-17 years = 98%), with 91% intubated on the first attempt (0-2 years = 86%, 3-8 years = 90%, and 9-17 years = 92%) and 87% intubated on the first attempt without oxygen desaturation (0-2 years = 80%, 3-8 years = 88%, and 9-17 years = 90%). A sharp decline in intubation success was observed with preoxygenation SpO2 values < 97% across all patients. Younger patients (0-2 years) had lower initial SpO2 values and decreased first-attempt success rates with and without desaturation. These patients were less likely to receive PPV during preoxygenation attempts and had lower use of video laryngoscopy or a bougie on the initial intubation attempt. CONCLUSION: In this study, we documented high success rates for air medical pediatric RSI. Higher target SpO2 values may be justified during preoxygenation. Intubation success, PPV use for preoxygenation, video laryngoscopy, and the use of a bougie were lower for younger patients.