Pathogenesis of sleep disordered breathing in the setting of opioid use: A multiple mediation analysis using physiology.

STUDY OBJECTIVES: Opioid medications are commonly used and are known to impact both breathing and sleep, and are linked with adverse health outcomes including death. Clinical data indicate that chronic opioid use causes central sleep apnea, and might also worsen obstructive sleep apnea. The mechanisms by which opioids influence sleep-disordered breathing pathogenesis are not established. METHODS: Patients who underwent clinically-indicated polysomnography confirming sleep-disordered breathing (SDB) (AHI≥5/hr) were included. Each patient using opioids was matched by sex, age, and BMI to three control individuals not using opioids. Physiology known to influence SDB pathogenesis were determined from validated polysomnography-based signal analysis. PSG and physiology paramters of interest were compared between opioid and control individuals, adjusted for covariates. Mediation analysis was used to evaluate the link between opioids, physiology, and polysomnographic metrics. RESULTS: 178 individuals using opioids were matched to 534 controls (median [IQR] age 59 [50,65] years, BMI 33 [29,41] kg/m2, 57% female, daily morphine equivalent 30 [20,80] mg). Compared with controls, opioids were associated with increased central apneas (2.8 vs 1.7 events/hr; p=0.001) and worsened hypoxemia (5 vs 3% sleep with SpO2<88%; p=0.013), with similar overall AHI. Use of opioids was associated with higher loop gain, a lower respiratory rate and higher respiratory rate variability. Higher loop gain and increased respiratory rate variability mediated the effect of opioids on central apnea, but did not mediate the effect on hypoxemia. CONCLUSIONS: Opioids have multi-level effects impacting SDB. Targeting these factors may help mitigate deleterious respiratory consequences of chronic opioid use.

The Effect of Obesity on Sleep Apnea Pathogenesis Differs in Women vs Men: Multiple Mediation Analyses in the Retrospective SNOOzzzE Cohort.

BACKGROUND AND OBJECTIVE: There are multiple mechanisms underlying obstructive sleep apnea (OSA) development. However, how classic OSA risk factors such as body mass index (BMI) and sex portend to OSA development have not been fully described. Thus, we sought to evaluate how obesity leads to OSA, and assess how these mechanisms differ between men and women. Methods The San Diego Multi-Outcome OSA Endophenotype (SNOOzzzE) cohort includes 3,319 consecutive adults who underwent a clinical in-laboratory polysomnography at the UCSD sleep clinic between 1/2017-12/2019. Using routine polysomnography signals, we determined OSA endotypes. We then performed mediation analyses stratified by sex to determine how BMI influenced apnea hypopnea index (AHI) using OSA endotypic traits as mediators. Results We included 2,146 patients of whom 919 (43%) were women and 1,227 (57%) were obese. BMI was significantly associated with AHI in both women and men. In men, the effect of BMI on AHI was partially mediated by a reduction in upper airway stiffness (31% of total effect, TE), by a reduction in circulatory delay (16%TE), and by an increase in arousal threshold (7%TE). In women, the effect of BMI on AHI was partially mediated by a reduction in circulatory delay (22%TE). Discussion BMI-related OSA pathogenesis differs by sex. An increase in upper airway collapsibility (in men) is consistent with prior studies. A reduction in circulatory delay may lead to shorter and thus more events per hour (i.e., higher AHI), while the association between a higher arousal threshold and higher AHI may reflect reverse causation.

Performance of a commercial smart watch compared to polysomnography reference for overnight continuous oximetry measurement and sleep apnea evaluation.

STUDY OBJECTIVES: To evaluate the accuracy and precision of continuous overnight oxygen saturation (SpO2) measurement by a commercial wrist device (WD) incorporating high-grade sensors, and investigate WD estimation of sleep-disordered breathing by quantifying overnight oxygen desaturation index (ODI) compared to polysomnography (PSG) ODI and apnea-hypopnea index (AHI) with and without sleep questionnaire data, to assess WD ability to detect obstructive sleep apnea (OSA) and determine its severity. METHODS: Participants completed sleep questionnaires, had a WD (Samsung Galaxy Watch 4) placed on their wrist, and underwent attending, in-lab overnight PSG (Nihon Kohden) with pulse oximetry probe secured either to a finger or ear lobe. PSG data was scored by a single experienced registered PSG technologist. Statistical analysis included demographic characteristics, continuous SpO2 measurement WD vs PSG root mean square error (RMSE) with Bland Altman plot and linear regression associations. Predictive models for PSG ODI and AHI severity were built using logistic regression with probability cutoffs determined via receiver operating curve (ROC) characteristics. RESULTS: The 51 participants analyzed had median age of 49 (range 22-78) years, 66.7% were male, with median body mass index (BMI) 28.1 (range 20.1, 47.3) kg/m2 with race/ethnicity distribution of 49.0% Caucasian, 25.5% Hispanic, 9.8% African-American, 9.8% Asian, and 5.9% Middle Eastern. WD vs PSG continuous SpO2 measurement in percentage points demonstrated bias of 0.91 (CI95 0.38, 1.45), standard deviation 2.37 (CI95 2.36, 2.38), and RMSE 2.54 (CI95 2.34, 2.73). WD area under the curve (AUC) ROC characteristics for predicting PSG were 0.882 ODI>15/h, 0.894 AHI>30/h, 0.800 AHI>15/h, and 0.803 AHI>5/h. WD plus select sleep questionnaire AUCs for predicting PSG were 0.943 AHI>30/h, 0.868 AHI>15/h, and 0.863 AHI>5/h. CONCLUSIONS: The WD conducted reliable overnight continuous SpO2 monitoring with RMSE <3% vs PSG. Predictive models of PSG AHI based on WD measurements alone, or plus sleep questionnaires, demonstrated excellent to outstanding discrimination for OSA identification and severity. Longitudinal WD use should be evaluated promptly based on WD potential to improve accessibility and accuracy of OSA testing, as well as support treatment follow-up.

Growth of Complex Syntax: Coordinate and Subordinate Clause Use in Elementary School-Aged Children.

PURPOSE: Production of complex syntax is a hallmark of later language development; however, most of the research examining age-related changes has focused on adolescents or analyzed narrative language samples. Research documenting age-related changes in the production of complex syntax in elementary school-aged children in conversational language samples is limited. Therefore, the purpose of this article is to examine age-related changes in the production of coordinate and subordinate clauses in children between 5 and 10 years of age obtained from 50-utterance conversational language samples. METHOD: The analytic sample included 196 children with typical language development, who ranged in age from 5;0 to 10;11 (years;months; girls = 103; boys = 96; three cases were excluded). Fifty-utterance conversational language samples were examined for use of coordinate and subordinate clauses. RESULTS: Results of regression analyses indicated that the production of coordinate and subordinate clauses could be predicted from age. The proportion of utterances that included subordinate clauses increased 0.20% for every month increase in age (p < .001). Coordinate clauses also continued to grow, although at a slower rate (0.10% increase for every month increase in age, p < .001). Finally, the proportion of simple utterances (i.e., utterances without coordinate or subordinate clauses) decreased with age (0.40% decrease for every month increase in age, p < .001). CONCLUSIONS: This study indicated that as children's age increased, they used fewer, simple, one-clause sentences and more utterances that included subordinate clauses, with or without coordinate clauses. These results were obtained from 50-utterance language samples, further supporting use of language sampling to develop intervention goals and monitor progress in therapy. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25262725.

Temporal Trends in Methamphetamine Use in Patients Admitted to the Hospital: A Retrospective Cohort Study.

OBJECTIVES: Although methamphetamine use is common, the scope of methamphetamine use and outcomes for patients admitted to the hospital is unclear. This study aims to identify the prevalence of methamphetamine use from January 2012 to January 2022, coingestions, hospital course, and readmission rate of admitted patients. METHODS: This was a retrospective cohort study conducted on patients admitted to our center with the following inclusions: age older than 18 years, positive/"pending confirm" value for methamphetamine on urine drug screen, and/or an International Classification of Diseases, Tenth Revision, code related to stimulant use disorder as an active issue. Urine drug screen data are reported as methamphetamine +/- and polysubstance (PS) +/-. Patient demographics, admission diagnosis, and hospital course were extracted. Statistical tests used included t tests and Mann-Whitney U tests. RESULTS: A total of 19,159 encounters were included, representing 12,057 unique patients. The median (interquartile range) age was 43 (33-54) years. Of all encounters, 35.3% were methamphetamine + and PS -, and 46.3% were methamphetamine + and PS +. Hospitalizations increased from 883 in 2012 to 2532 in 2021. The median (IQR) hospital stay was 48 (48-120) hours. Of all encounters, 16.8% included an intensive care unit (ICU) admission, and the median ICU stay was 42 (21-87) hours. A total of 2988 patients (24.7%) were readmitted within the study period, and 4988 (71.5%) returned within 1 year of the previous encounter. In context of all emergency department admissions from 2013 to 2022, 13.1% had a urine drug screen + for methamphetamine. CONCLUSIONS: Hospitalizations with recent methamphetamine use doubled at our institution from 2012 to 2022. In addition, 1 in 4 is readmitted (typically within 1 year), and a minority requires ICU care.

Objectively measured peri-vaccination sleep does not predict COVID-19 breakthrough infection.

Prior studies have shown that sleep duration peri-vaccination influences an individual's antibody response. However, whether peri-vaccination sleep affects real-world vaccine effectiveness is unknown. Here, we tested whether objectively measured sleep around COVID-19 vaccination affected breakthrough infection rates. DETECT is a study of digitally recruited participants who report COVID-19-related information, including vaccination and illness data. Objective sleep data are also recorded through activity trackers. We compared the impact of sleep duration, sleep efficiency, and frequency of awakenings on reported breakthrough infection after the 2nd vaccination and 1st COVID-19 booster. Logistic regression models were created to examine if sleep metrics predicted COVID-19 breakthrough infection independent of age and gender. Self-reported breakthrough COVID-19 infection following 2nd COVID-19 vaccination and 1st booster. 256 out of 5265 individuals reported a breakthrough infection after the 2nd vaccine, and 581 out of 2583 individuals reported a breakthrough after the 1st booster. There was no difference in sleep duration between those with and without breakthrough infection. Increased awakening frequency was associated with breakthrough infection after the 1st booster with 3.01 ± 0.65 awakenings/hour in the breakthrough group compared to 2.82 ± 0.65 awakenings/hour in those without breakthrough (P < 0.001). Cox proportional hazards modeling showed that age < 60 years (hazard ratio 2.15, P < 0.001) and frequency of awakenings (hazard ratio 1.17, P = 0.019) were associated with breakthrough infection after the 1st booster. Sleep duration was not associated with breakthrough infection after COVID vaccination. While increased awakening frequency during sleep was associated with breakthrough infection beyond traditional risk factors, the clinical implications of this finding are unclear.

Impact of a deep learning sepsis prediction model on quality of care and survival.

Sepsis remains a major cause of mortality and morbidity worldwide. Algorithms that assist with the early recognition of sepsis may improve outcomes, but relatively few studies have examined their impact on real-world patient outcomes. Our objective was to assess the impact of a deep-learning model (COMPOSER) for the early prediction of sepsis on patient outcomes. We completed a before-and-after quasi-experimental study at two distinct Emergency Departments (EDs) within the UC San Diego Health System. We included 6217 adult septic patients from 1/1/2021 through 4/30/2023. The exposure tested was a nurse-facing Best Practice Advisory (BPA) triggered by COMPOSER. In-hospital mortality, sepsis bundle compliance, 72-h change in sequential organ failure assessment (SOFA) score following sepsis onset, ICU-free days, and the number of ICU encounters were evaluated in the pre-intervention period (705 days) and the post-intervention period (145 days). The causal impact analysis was performed using a Bayesian structural time-series approach with confounder adjustments to assess the significance of the exposure at the 95% confidence level. The deployment of COMPOSER was significantly associated with a 1.9% absolute reduction (17% relative decrease) in in-hospital sepsis mortality (95% CI, 0.3%-3.5%), a 5.0% absolute increase (10% relative increase) in sepsis bundle compliance (95% CI, 2.4%-8.0%), and a 4% (95% CI, 1.1%-7.1%) reduction in 72-h SOFA change after sepsis onset in causal inference analysis. This study suggests that the deployment of COMPOSER for early prediction of sepsis was associated with a significant reduction in mortality and a significant increase in sepsis bundle compliance.

Assessment of Family Medicine Obstetrics Fellowship Websites in the United States: Content and Usability.

INTRODUCTION: The United States is experiencing maternity care shortages. Family physicians can play a role in addressing these shortages. Family medicine obstetrics fellowships train family physicians in obstetrics care. Fellowship websites are important for promoting programs and attracting applicants. However, whether websites provide sufficient program information is unknown. This study aimed to assess completeness and utility of family medicine obstetrics fellowship websites across the United States. METHOD: The study analyzed 46 family medicine obstetrics fellowship websites. The component analysis evaluated the presence of 17 components related to orientation, curriculum, program, personnel, and additional content. The qualitative analysis included ratings for navigation and application, information quality, and esthetics. Analysis included percentages for websites and components and average qualitative ratings. RESULTS: Common components included overviews, training requirements, and contact information. Description of the patient population was the least common component. Usability ratings varied across programs, with higher ratings observed for navigation and application, and information quality. Esthetics and visual appeal received lower ratings. Regional analysis indicated that websites from fellowships in the West and Southwest tended to include more components compared to those in the Southeast. DISCUSSION: Family medicine obstetrics fellowship websites serve as valuable sources of program information for prospective applicants. However, not all websites include essential program details. Some information is rarely provided. Given the shortage of maternity care providers, it is crucial to develop informative and functional websites to attract applicants. Improving website content and design could prove to be a cost-effective strategy to increase the number of applicants.

Loop Gain as a Predictor of Blood Pressure Response in Patients Treated for Obstructive Sleep Apnea: Secondary Analysis of a Clinical Trial.

Rationale: Randomized trials have shown inconsistent cardiovascular benefits from obstructive sleep apnea (OSA) therapy. Intermittent hypoxemia can increase both sympathetic nerve activity and loop gain ("ventilatory instability"), which may thus herald cardiovascular treatment benefit. Objectives: To test the hypothesis that loop gain predicts changes in 24-hour mean blood pressure (MBP) in response to OSA therapy and compare its predictive value against that of other novel biomarkers. Methods: The HeartBEAT (Heart Biomarker Evaluation in Apnea Treatment) trial assessed the effect of 12 weeks of continuous positive airway pressure (CPAP) versus oxygen versus control on 24-hour MBP. We measured loop gain and hypoxic burden from sleep tests and identified subjects with a sleepy phenotype using cluster analysis. Associations between biomarkers and 24-h MBP were assessed in the CPAP/oxygen arms using linear regression models adjusting for various covariates. Secondary outcomes and predictors were analyzed similarly. Results: We included 93 and 94 participants in the CPAP and oxygen arms, respectively. Overall, changes in 24-hour MBP were small, but interindividual variability was substantial (mean [standard deviation], -2 [8] and 1 [8] mm Hg in the CPAP and oxygen arms, respectively). Higher loop gain was significantly associated with greater reductions in 24-hour MBP independent of covariates in the CPAP arm (-1.5 to -1.9 mm Hg per 1-standard-deviation increase in loop gain; P ⩽ 0.03) but not in the oxygen arm. Other biomarkers were not associated with improved cardiovascular outcomes. Conclusions: To our knowledge, this is the first study suggesting that loop gain predicts blood pressure response to CPAP therapy. Eventually, loop gain estimates may facilitate patient selection for research and clinical practice. Clinical trial registered with www.clinicaltrials.gov (NCT01086800).

Upper airway imaging and function in obstructive sleep apnea in people with and without HIV.

Obstructive sleep apnea (OSA) is common in people living with human immunodeficiency virus (HIV) (PLWH), but the underlying mechanisms are unclear. With improved long-term survival among PLWH, aging and obesity are increasingly prevalent in this population. These are also strong risk factors for the development of obstructive sleep apnea. We used magnetic resonance imaging (MRI) to measure upper airway (UA) anatomy and tongue fat content in PLWH with OSA (PLWH + OSA, n = 9) and in age-, sex-, and body mass index (BMI)-matched OSA controls (OSA, n = 11). We also quantified change in UA dimension during tidal breathing (during wakefulness and natural sleep) at four anatomical levels from the hard palate to the epiglottis along with synchronous MRI-compatible electroencephalogram and nasal flow measurements. All participants underwent on a separate night a baseline polysomnogram to assess OSA severity and an additional overnight physiological sleep study to measure OSA traits. We found no difference between the PLWH + OSA and the OSA control group in UA volume [PLWH + OSA: 12.8 mL (10.1-17.0), OSA: 14.0 mL (13.3-17.9), median (IQR)] or tongue volume [PLWH + OSA: 140.2 mL (125.1-156.9), OSA: 132.4 mL (126.8-154.7)] and a smaller tongue fat content in PLWH + OSA [11.2% (10.2-12.4)] than in the OSA controls [14.8% (13.2-15.5), P = 0.046]. There was no difference in the dynamic behavior of the UA between the two groups. When pooled together, both static and dynamic imaging metrics could be correlated with measures of UA mechanical properties. Our data suggest similar underlying UA physiology in OSA in subjects with and without HIV.NEW & NOTEWORTHY Obstructive sleep apnea is common in people living with human immunodeficiency virus (HIV), but the underlying mechanisms are unclear. We did not find differences in upper airway morphology using magnetic resonance imaging (MRI) during wake and natural sleep between people living with HIV (PLWH) with obstructive sleep apnea (OSA) and age, gender, and body mass index (BMI)-matched people with OSA but without HIV. Nor were there differences in tongue volume or changes in airway size during inspiration and expiration. MRI-derived anatomy was correlated with measures of airway collapse.

Evaluating maternal health capacity building in rural and underserved areas: a research protocol.

INTRODUCTION: The US is currently experiencing a maternal health crisis. Maternal morbidity and mortality in the US are higher than in other developed nations and continue to rise. Infant mortality, likewise, is higher in the US than in other developed nations. Limited availability of maternal health services, particularly in rural areas, contributes to this crisis. Maternal health outcomes are poorer, and maternal care workforce shortages are more severe in rural areas of the US. In rural areas where obstetric specialists are rare, many patients rely on family medicine physicians for maternity care. However, the number of family medicine physicians who provide maternal care services is decreasing, aggravating shortages. Calls have been made to build maternal care capacity in rural areas. The role family medicine will play in addressing the maternal health crisis is not clear. Maternal care shortages are complex issues resulting from multiple factors; likewise, efforts to build maternal health capacity are challenging and require multifaceted approaches. METHODS: With funding from the Health Resources and Services Administration (HRSA), the University of Utah seeks to address the shortage of quality maternity care in rural and underserved areas of Utah by strengthening partnerships, enhancing maternal care training of family medicine residents and obstetrics fellows, and improving the transition from training to rural practice for residents and fellows. This protocol describes the evaluation of the HRSA-funded project. The evaluation includes three components. Component 1 consists of qualitative interviews with a diverse group of maternal health providers, administrators, educators and academics, patients, and others. Interviews will be analyzed using qualitative content analysis. Component 2 is a survey of family medicine residents and obstetrics fellows, which aims to increase understanding of the factors and circumstances influencing intention to practice in rural or underserved areas and to provide maternal health services. Component 3 involves surveying fellowship alumni and tracking graduates to assess effectiveness of training programs in producing physicians who provide maternal health services in rural and underserved areas. Surveys will be analyzed with descriptive statistics including means, frequencies, and cross-tabulations. If sample size and participation provide sufficient power, statistical tests will be included in analyses. RESULTS: Evaluation results will help to fill an important gap in research literature concerning outcomes of projects and initiatives designed to build maternal care capacity in rural areas of the US. In addition, results will provide valuable information regarding effective practices for building capacity, which can be adopted elsewhere to address maternal care shortages. Finally, results will help to define the role of family medicine in addressing the maternal health crisis. Amid maternal care shortages, fewer and fewer family medicine physicians are providing maternal care in their practice. Evaluation results will clarify the role of training and preparation of family medicine residents in addressing workforce shortages. CONCLUSION: This evaluation will provide important contributions, but additional research is needed, including research protocols and studies of project outcomes, to understand how best to resolve the maternal care crisis in the US.

Electronic Health Record-Driven Approaches in Primary Care to Strengthen Hypertension Management Among Racial and Ethnic Minoritized Groups in the United States: Systematic Review.

BACKGROUND: Managing hypertension in racial and ethnic minoritized groups (eg, African American/Black patients) in primary care is highly relevant. However, evidence on whether or how electronic health record (EHR)-driven approaches in primary care can help improve hypertension management for patients of racial and ethnic minoritized groups in the United States remains scarce. OBJECTIVE: This review aims to examine the role of the EHR in supporting interventions in primary care to strengthen the hypertension management of racial and ethnic minoritized groups in the United States. METHODS: A search strategy based on the PICO (Population, Intervention, Comparison, and Outcome) guidelines was utilized to query and identify peer-reviewed articles on the Web of Science and PubMed databases. The search strategy was based on terms related to racial and ethnic minoritized groups, hypertension, primary care, and EHR-driven interventions. Articles were excluded if the focus was not hypertension management in racial and ethnic minoritized groups or if there was no mention of health record data utilization. RESULTS: A total of 29 articles were included in this review. Regarding populations, Black/African American patients represented the largest population (26/29, 90%) followed by Hispanic/Latino (18/29, 62%), Asian American (7/29, 24%), and American Indian/Alaskan Native (2/29, 7%) patients. No study included patients who identified as Native Hawaiian/Pacific Islander. The EHR was used to identify patients (25/29, 86%), drive the intervention (21/29, 72%), and monitor results and outcomes (7/29, 59%). Most often, EHR-driven approaches were used for health coaching interventions, disease management programs, clinical decision support (CDS) systems, and best practice alerts (BPAs). Regarding outcomes, out of 8 EHR-driven health coaching interventions, only 3 (38%) reported significant results. In contrast, all the included studies related to CDS and BPA applications reported some significant results with respect to improving hypertension management. CONCLUSIONS: This review identified several use cases for the integration of the EHR in supporting primary care interventions to strengthen hypertension management in racial and ethnic minoritized patients in the United States. Some clinical-based interventions implementing CDS and BPA applications showed promising results. However, more research is needed on community-based interventions, particularly those focusing on patients who are Asian American, American Indian/Alaskan Native, and Native Hawaiian/Pacific Islander. The developed taxonomy comprising "identifying patients," "driving intervention," and "monitoring results" to classify EHR-driven approaches can be a helpful tool to facilitate this.

Effectiveness of long-term noninvasive ventilation measured by remote monitoring in neuromuscular disease.

Background and objective: Patients with neuromuscular disease are often treated with home noninvasive ventilation (NIV) with devices capable of remote patient monitoring. We sought to determine whether long-term NIV data could provide insight into the effectiveness of ventilation over time. Methods: We abstracted available longitudinal data for adults with neuromuscular disease in monthly increments from first available to most recent. Generalised linear mixed-effects modelling with subject-level random effects was used to evaluate trajectories over time. Results: 1799 months of data across 85 individuals (median age 61, interquartile range (IQR) 46-71 years; 44% female; 49% amyotrophic lateral sclerosis (ALS)) were analysed, with a median (IQR) of 17 (8-35) months per individual. Over time, tidal volume increased and respiratory rate decreased. Dynamic respiratory system compliance decreased, accompanied by increased pressure support. Compared to volume-assured mode, fixed-pressure modes were associated with lower initial tidal volume, higher respiratory rate and lower pressures, which did not fully equalise with volume-assured mode over time. Compared with non-ALS patients, those with ALS had lower initial pressure support, but faster increases in pressure support over time, and ALS was associated wtih a more robust increase in respiratory rate in response to low tidal volume. Nonsurvivors did not differ from survivors in ventilatory trajectories over time, but did exhibit decreasing NIV use prior to death, in contrast with stable use in survivors. Conclusion: NIV keeps breathing patterns stable over time, but support needs are dynamic and influenced by diagnosis and ventilation mode. Mortality is preceded by decreased NIV use rather than inadequate support during use.

The Remarkable Legacy of Theodor O. Diener (1921-2023): Preeminent Plant Pathologist and the Discoverer of Viroids.

Theodor ("Ted") Otto Diener, the discoverer of viroids, died on 28 March 2023 at his home in Beltsville, Maryland, USA [...].

Using Cardiohelp, Quadrox, and Nautilus Extracorporeal Membrane Oxygenators as Vascular Access for Hemodialysis, Continuous Renal Replacement Therapy, and Plasmapheresis: A Brief Technical Report.

The use of intermittent hemodialysis (iHD), and continuous renal replacement therapy (CRRT), along with extracorporeal membrane oxygenation (ECMO) in patients with acute kidney injury (AKI) and end-stage renal disease (ESRD) is very common. In this technical report, we describe the methods to perform these dialytic therapies safely and effectively using the ECMO circuit in lieu of a separate dialysis catheter. Specifically, we describe in detail how to connect these kidney replacement therapy modalities to a Quadrox, Nautilus, and Cardiohelp HLS (combined oxygenator and pump) oxygenator. The dialysis (iHD or CRRT) inlet is attached to the post-oxygenators Luer-Lock, whereas the return is attached to the pre-oxygenator Luer-Lock, both with a dual lumen pigtail. We also discuss the technical aspects of performing plasmapheresis in conjunction with ECMO and iHD or CRRT. Finally, we highlight the fact that the reported technique does not require modifying the ECMO cannulas/tubing which helps maximize safety.

Supplemental oxygen and noninvasive ventilation.

The respiratory system attempts to maintain normal levels of oxygen and carbon dioxide. However, airflow limitation, parenchymal abnormalities and dysfunction of the respiratory pump may be compromised in individuals with advanced COPD, eventually leading to respiratory failure, with reduced arterial oxygen tension (hypoxaemia) and/or increased arterial carbon dioxide tension (P aCO2 ; hypercapnia). Hypoxaemia may persist in individuals with severe COPD despite smoking cessation and optimisation of pharmacotherapy. Long-term oxygen therapy (LTOT) can improve survival in those with severe daytime hypoxaemia, whereas those with less severe hypoxaemia may only have improved exercise capacity and dyspnoea. Changes in respiratory physiology that occur during sleep further predispose to hypoxaemia, particularly in individuals with COPD. However, the major cause of hypoxaemia is hypoventilation. Noninvasive ventilation (NIV) may reduce mortality and need for intubation in individuals with COPD and acute hypercapnic respiratory failure. However, NIV may also improve survival and quality of life in individuals with stable, chronic hypercapnia and is now suggested for those with prolonged hypercapnia (e.g. P aCO2 >55 mmHg 2-6 weeks after hospital discharge) when clinically stable and after optimisation of medical therapy including LTOT if indicated. Many questions remain about the optimal mode, settings and goal of NIV therapy.