Comparison of different types of ultrasound probes for lung ultrasound in neonates-A prospective randomized comparison study.

OBJECTIVE: To determine the effect of different types of probes for lung ultrasound in neonates. DESIGN: Prospective, blinded, randomized, comparative study between 2020 and 2022. SETTING: Single-center study at a third level neonatal unit. PATIENTS: Hemodynamically stable infants with either nasal continuous positive airway pressure, high flow nasal cannula or without respiratory support. INTERVENTION: Lung ultrasound using either an echo or microconvex probe. As control, the linear probe was used. MAIN OUTCOME MEASURES: Primary outcome measure was neonatologist performed lung ultrasound (NPLUS) score. Secondary outcome measures were number of B-Lines, thickness of the pleural line and subjective image quality. Furthermore, correlation between NPLUS results and clinical data was assessed. RESULTS: A total of 1584 video loops from 66 patients, with a mean corrected gestational age of 33.8 weeks (SD 4.23) and weight of 1950g (SD 910), respectively, were analyzed. NPLUS score was estimated lower with the echo- and microconvex probe compared to the linear probe, with a coefficient of -2.95 (p < 0.001) and -1.09 (p = 0.19), respectively. Correlation between the pulse oximetric saturation/fraction of inspired oxygen ratio and NPLUS score was moderately strong and best using the microconvex probe (Spearman's rho = -0.63, p<0.001). CONCLUSION: Our results not only confirm the current recommendations, but also demonstrate the extent of the varying results when different probes are used. The differences we discovered call for caution in interpreting scores, especially in the context of guiding therapies and communicating prognoses. Finally, the correlation between NPLUS score and clinical parameters contributes to validating the use of this diagnostic tool.

Continuous Positive Airway Pressure versus Differential Lung Ventilation during One Lung Ventilation for Thoracic Surgery.

INTRODUCTION: One lung ventilation (OLV) is a technique used during lung resection surgery to facilitate optimal surgical conditions. However, this may result in severe hypoxemia due to the right-to-left shunt created in the collapsed lung. Several techniques are used to overcome hypoxemia, one of which is continuous positive airway pressure (CPAP) to the non-dependent lung. Another technique is ventilating the non-dependent lung with a minimal volume, thus creating differential lung ventilation (DLV) or split lung ventilation (SLV). In this study, we compared the efficacy of CPAP to DLV during video-assisted thoracoscopic (VATS) lung resection. MATERIALS AND METHODS: In this single-center randomized controlled, cross-over study, each patient acted as his control as well as the study. Patients crossed over from SLV to CPAP (or vice versa) with an interval period during which only OLV was used (control period). The primary objective of the study was to observe the changes in oxygenation, ventilation, and the surgeons' perception of the surgical field using CPAP or SLV to the non-ventilated lung during the period of OLV in patients undergoing thoracic surgery. RESULTS: The study revealed that oxygenation was significantly better when using SLV to the non-ventilated lung during the period of OLV (P = 0.03). However, the surgeon found a significantly better surgical field when applying CPAP to the surgical field. CONCLUSIONS: The study showed that using SLV to the non-ventilated lung during the period of OLV was superior in terms of oxygenation, although it interfered more with the surgical field.

Respiratory support with standard low-flow oxygen therapy, high-flow oxygen therapy or continuous positive airway pressure in adults with acute hypoxaemic respiratory failure in a resource-limited setting: protocol for a randomised, open-label, clinical trial - the Acute Respiratory Intervention StudiEs in Africa (ARISE-AFRICA) study.

RATIONALE: Acute hypoxaemic respiratory failure (AHRF) is associated with high mortality in sub-Saharan Africa. This is at least in part due to critical care-related resource constraints including limited access to invasive mechanical ventilation and/or highly skilled acute care workers. Continuous positive airway pressure (CPAP) and high-flow oxygen by nasal cannula (HFNC) may prove useful to reduce intubation, and therefore, improve survival outcomes among critically ill patients, particularly in resource-limited settings, but data in such settings are lacking. The aim of this study is to determine whether CPAP or HFNC as compared with standard oxygen therapy, could reduce mortality among adults presenting with AHRF in a resource-limited setting. METHODS: This is a prospective, multicentre, randomised, controlled, stepped wedge trial, in which patients presenting with AHRF in Uganda will be randomly assigned to standard oxygen therapy delivered through a face mask, HFNC oxygen or CPAP. The primary outcome is all-cause mortality at 28 days. Secondary outcomes include the number of patients with criteria for intubation at day 7, the number of patients intubated at day 28, ventilator-free days at day 28 and tolerance of each respiratory support. ETHICS AND DISSEMINATION: The study has obtained ethical approval from the Research and Ethics Committee, School of Biomedical Sciences, College of Health Sciences, Makerere University as well as the Uganda National Council for Science and Technology. Patients will be included after informed consent. The results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04693403. PROTOCOL VERSION: 8 September 2023; version 5.

Comparison of "IN-REC-SUR-E" and LISA in preterm neonates with respiratory distress syndrome: a randomized controlled trial (IN-REC-LISA trial).

BACKGROUND: Surfactant is a well-established therapy for preterm neonates affected by respiratory distress syndrome (RDS). The goals of different methods of surfactant administration are to reduce the duration of mechanical ventilation and the severity of bronchopulmonary dysplasia (BPD); however, the optimal administration method remains unknown. This study compares the effectiveness of the INtubate-RECruit-SURfactant-Extubate (IN-REC-SUR-E) technique with the less-invasive surfactant administration (LISA) technique, in increasing BPD-free survival of preterm infants. This is an international unblinded multicenter randomized controlled study in which preterm infants will be randomized into two groups to receive IN-REC-SUR-E or LISA surfactant administration. METHODS: In this study, 382 infants born at 24+0-27+6 weeks' gestation, not intubated in the delivery room and failing nasal continuous positive airway pressure (nCPAP) or nasal intermittent positive pressure ventilation (NIPPV) during the first 24 h of life, will be randomized 1:1 to receive IN-REC-SUR-E or LISA surfactant administration. The primary outcome is a composite outcome of death or BPD at 36 weeks' postmenstrual age. The secondary outcomes are BPD at 36 weeks' postmenstrual age; death; pulse oximetry/fraction of inspired oxygen; severe intraventricular hemorrhage; pneumothorax; duration of respiratory support and oxygen therapy; pulmonary hemorrhage; patent ductus arteriosus undergoing treatment; percentage of infants receiving more doses of surfactant; periventricular leukomalacia, severe retinopathy of prematurity, necrotizing enterocolitis, sepsis; total in-hospital stay; systemic postnatal steroids; neurodevelopmental outcomes; and respiratory function testing at 24 months of age. Randomization will be centrally provided using both stratification and permuted blocks with random block sizes and block order. Stratification factors will include center and gestational age (24+0 to 25+6 weeks or 26+0 to 27+6 weeks). Analyses will be conducted in both intention-to-treat and per-protocol populations, utilizing a log-binomial regression model that corrects for stratification factors to estimate the adjusted relative risk (RR). DISCUSSION: This trial is designed to provide robust data on the best method of surfactant administration in spontaneously breathing preterm infants born at 24+0-27+6 weeks' gestation affected by RDS and failing nCPAP or NIPPV during the first 24 h of life, comparing IN-REC-SUR-E to LISA technique, in increasing BPD-free survival at 36 weeks' postmenstrual age of life. TRIAL REGISTRATION: ClinicalTrials.gov NCT05711966. Registered on February 3, 2023.

Cardio-metabolic health effects of CPAP treatment for sleep apnoea during weight loss: A randomised controlled pilot trial.

BACKGROUND AND AIMS: This study assessed whether the addition of continuous positive airway pressure (CPAP) during weight loss would enhance cardiometabolic health improvements in patients with obesity and Obstructive Sleep Apnoea (OSA). METHODS AND RESULTS: Patients with overweight or obesity, pre-diabetes and moderatesevere OSA were randomised to receive CPAP therapy with a weight loss programme (CPAP+WL) or a weight loss programme alone (WL alone). PRIMARY OUTCOME: 2-hour glucose assessed by an oral glucose tolerance test. SECONDARY OUTCOMES: 24 hr blood pressure, body composition (DEXA) and fasting blood markers. 17 patients completed 3-month follow-up assessments (8 CPAP+WL and 9 WL alone). Overall, participants in both groups lost ∼12 kg which reduced polysomnography determined OSA severity by ∼45 %. In the CPAP+WL group, CPAP use (compliance 5.29 hrs/night) did not improve any outcome above WL alone. There was no improvement in 2-hour glucose in either group. However, in the pooled (n = 17) analysis there were overall improvements in most outcomes including insulin sensitivity (.000965 units, p = .008), sleep systolic BP (- 16.2 mmHg, p = .0003), sleep diastolic BP (-9.8 mmHg, p = 0.02), wake diastolic BP (- 4.3 mmHg, p = .03) and sleepiness (Epworth Sleepiness Score -3.2, p = .0003). In addition, there were reductions in glucose area under the curve (-230 units, p = .009), total (-0.86 mmol/L, p = 0.006) and LDL cholesterol (-0.58 mmol/L, p = 0.007), triglycerides (-0.75 mmol/L, p = 0.004), fat mass (-7.6 kg, p < .0001) and abdominal fat (-310 cm3, p < .0001). CONCLUSION: Weight loss reduced OSA and improved sleepiness and cardiometabolic health. These improvements were not further enhanced by using CPAP. Results suggest weight loss should be the primary focus of treatment for patients with OSA and obesity.

Obstructive Sleep Apnea in Adults: Common Questions and Answers.

Obstructive sleep apnea (OSA) is a common disorder that affects quality of life and is associated with comorbidities such as hypertension, atrial fibrillation, heart failure, coronary heart disease, type 2 diabetes mellitus, and stroke. OSA is characterized by a reduction or cessation of breathing during sleep, resulting in intermittent hypoxemia, autonomic fluctuation, and sleep fragmentation. The U.S. Preventive Services Task Force states that there is insufficient evidence to recommend routine screening for OSA in the absence of symptoms. OSA should be considered in patients with excessive daytime fatigue, unrestful sleep, persistent snoring, and nocturnal awakenings with gasping or choking. The STOP-BANG questionnaire is the most sensitive screening tool for OSA, and the diagnostic standard is polysomnography with an observed apnea-hypopnea index greater than 5 in the presence of symptoms or greater than 15 without symptoms. Home sleep apnea testing is a useful diagnostic option in patients who have symptoms consistent with moderate to severe OSA without significant cardiopulmonary comorbidities. Positive airway pressure, with a humidified nasal or facial mask, is the first-line treatment for adults with OSA. Weight loss is a beneficial adjunct to treatment through intensive lifestyle modification, medications, or bariatric surgery. Alternatives for patients intolerant of or nonadherent to positive airway pressure include changing the type of mask used, mandibular advancement devices, hypoglossal nerve stimulation, and other surgical interventions. Although many OSA therapies effectively improve daytime sleepiness and blood pressure, none have demonstrated a mortality benefit in randomized controlled trials.

Neonatal respiratory complications in twins at 36-38 weeks of gestation.

BACKGROUND: Twin pregnancies are associated with a high risk of perinatal mortality and morbidity. Late preterm or early term delivery is frequently performed to avoid unexpected fetal death in uncomplicated twin pregnancies. Nonetheless, delivery before full term is associated with neonatal respiratory complications. This study aimed to evaluate perinatal respiratory complications in twins delivered between 36 and 38 weeks of gestation. METHODS: A retrospective cohort study was conducted on twins delivered between 36 and 38 weeks of gestation from January 2008 to June 2020. The primary outcomes were the incidence of composite neonatal respiratory morbidity, which included respiratory distress syndrome, transient tachypnea of the newborn, meconium aspiration syndrome, mechanical ventilation or continuous positive airway pressure according to gestational age at delivery, and chorionicity. The relationship between gestational age at delivery and composite neonatal respiratory morbidity was evaluated using multivariate logistic regression analysis adjusted for potential confounders. RESULTS: This study included 1608 twins (614 monochorionic diamniotic twins, 994 dichorionic diamniotic twins). At 36, 37, and 38 weeks of gestation, the frequencies of composite neonatal respiratory morbidity were 19.4%, 10.7%, and 9.2% in dichorionic diamniotic twins and 13.6%, 8.7%, and 9.4% in monochorionic diamniotic twins, respectively. In dichorionic diamniotic twins, the composite neonatal respiratory morbidity rate was higher for twins delivered at 36 weeks of gestation than for those delivered at 37 weeks. No significant differences between monochorionic diamniotic twins were detected. CONCLUSIONS: In uncomplicated dichorionic diamniotic twin pregnancies, delivery should be considered after 37 weeks of gestation to reduce neonatal respiratory complications.

[Factors affecting adherence to CPAP therapy in patients with obstructive sleep apnea syndrome]. / Faktory, vliyayushchie na priverzhennost' CPAP-terapii patsientov s sindromom obstruktivnogo apnoe sna.

OBJECTIVE: Analysis of factors affecting adherence to continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea (OSA). MATERIAL AND METHODS: The literature search was carried out using the databases PubMED, Google Scholar, E-library, Cyberleninka for the period 2013-2023 and included reviews and original articles. RESULTS: The main groups of factors affecting adherence to CPAP therapy in patients with OSA have been established. These include sociodemographic and socioeconomic factors, the severity of OSA and the severity of clinical symptoms, and psychosocial factors. Strategies that can improve adherence were identified (educational technologies for patients, telemedicine technologies, behavioral therapy, modern technical interventions). CONCLUSION: Factors that improve adherence to CPAP therapy are high levels of education and income, more severe OSA forms accompanied by daytime sleepiness, support from the patient's spouse and social support. Factors such as low levels of education and income, smoking, symptoms of depression and hypochondria, as well as side-effects worsen adherence to CPAP therapy, including refusal to continue treatment. It should be noted that all the identified factors are very closely associated with each other, so it is necessary to evaluate them comprehensively in each patient with OSA.

Comparison of the effect of two recruitment manoeuvres to conventional ventilation on lung atelectasis in paediatric laparoscopic surgery- a prospective randomised controlled trial.

BACKGROUND: There is a high incidence of pulmonary atelectasis during paediatric laparoscopic surgeries. The authors hypothesised that utilising a recruitment manoeuvre or using continuous positive airway pressure may prevent atelectasis compared to conventional ventilation. OBJECTIVE: The primary objective was to compare the degree of lung atelectasis diagnosed by lung ultrasound (LUS) using three different ventilation techniques in children undergoing laparoscopic surgeries. DESIGN: Randomised, prospective three-arm trial. SETTING: Single institute, tertiary care, teaching hospital. PATIENTS: Children of ASA PS 1 and 2 up to the age of 10 years undergoing laparoscopic surgery with pneumoperitoneum lasting for more than 30 min. INTERVENTION: Random allocation to one of the three study groups: CG group: Inspiratory pressure adjusted to achieve a TV of 5-8 ml/kg, PEEP of 5 cm H2O, respiratory rate adjusted to maintain end-tidal carbon dioxide (ETCO2) between 30-40 mm Hg with manual ventilation and no PEEP at induction. RM group: A recruitment manoeuvre of providing a constant pressure of 30 cm H2O for ten seconds following intubation was applied. A PEEP of 10 cm H2O was maintained intraoperatively. CPAP group: Intraoperative maintenance with PEEP 10 cm H2O with CPAP of 10 cm H2O at induction using mechanical ventilation was done. OUTCOME MEASURES: Lung atelectasis score at closure assessed by LUS. RESULTS: Post induction, LUS was comparable in all three groups. At the time of closure, the LUS for the RM group (8.6 ± 4.9) and the CPAP group (8.8 ± 6.8) were significantly lower (p < 0.05) than the CG group (13.3 ± 3.8). In CG and CPAP groups, the score at closure was significantly higher than post-induction. The PaO2/FiO2 ratio was significantly higher (p < 0.05) for the RM group (437.1 ± 44.9) and CPAP group (421.6 ± 57.5) than the CG group (361.3 ± 59.4) at the time of pneumoperitoneum. CONCLUSION: Application of a recruitment manoeuvre post-intubation or CPAP during induction and maintenance with a high PEEP leads to less atelectasis than conventional ventilation during laparoscopic surgery in paediatric patients. TRIAL REGISTRY: CTRI/2019/08/02058.

Treating sleep-disordered breathing of idiopathic pulmonary fibrosis patients with CPAP and nocturnal oxygen treatment. A pilot study : Sleep-disordered breathing treatment in IPF.

INTRODUCTION: Sleep-disordered breathing (SDB) is a major comorbidity in idiopathic pulmonary fibrosis (IPF) and is associated with a poor outcome. There is a lack of knowledge regarding the impact of SDB treatment on IPF. We assessed at one year: (1) the effect of CPAP and/or nocturnal oxygen therapy on IPF regarding lung function, blood mediators, and quality of life; (2) adherence to SDB treatment and SDB changes. METHODOLOGY: This is a prospective study of consecutive newly diagnosed IPF patients initiating anti-fibrotic treatment. Lung function, polysomnography, blood tests and quality of life questionnaires were performed at inclusion and after one year. Patients were classified as obstructive sleep apnoea (OSA), central sleep apnoea (CSA), and sleep-sustained hypoxemia (SSH). SDB therapy (CPAP and/or nocturnal oxygen therapy) was initiated if needed. RESULTS: Fifty patients were enrolled (36% had OSA, 22% CSA, and 12% SSH). CPAP was started in 54% of patients and nocturnal oxygen therapy in 16%. At one-year, polysomnography found improved parameters, though 17% of patients had to add nocturnal oxygen therapy or CPAP, while 33% presented SDB onset at this second polysomnography. CPAP compliance at one year was 6.74 h/night (SD 0.74). After one year, matrix metalloproteinase-1 decreased in OSA and CSA (p = 0.029; p = 0.027), C-reactive protein in OSA (p = 0.045), and surfactant protein D in CSA group (p = 0.074). There was no significant change in lung function. CONCLUSIONS: Treatment of SBD with CPAP and NOT can be well tolerated with a high compliance. IPF patients may exhibit SDB progression and require periodic re-assessment. Further studies to evaluate the impact of SDB treatment on lung function and serological mediators are needed.

Automated oxygen titration with non-invasive ventilation in hypoxaemic adults with cardiorespiratory disease: a randomised cross-over trial.

BACKGROUND: Closed-loop oxygen control systems automatically adjust the fraction of inspired oxygen (FiO2) to maintain oxygen saturation (SpO2) within a predetermined target range. Their performance with low and high-flow oxygen therapies, but not with non-invasive ventilation, has been established. We compared the effect of automated oxygen on achieving and maintaining a target SpO2 range with nasal high flow (NHF), bilevel positive airway pressure (bilevel) and continuous positive airway pressure (CPAP), in stable hypoxaemic patients with chronic cardiorespiratory disease. METHODS: In this open-label, three-way cross-over trial, participants with resting hypoxaemia (n=12) received each of NHF, bilevel and CPAP treatments, in random order, with automated oxygen titrated for 10 min, followed by 36 min of standardised manual oxygen adjustments. The primary outcome was the time taken to reach target SpO2 range (92%-96%). Secondary outcomes included time spent within target range and physiological responses to automated and manual oxygen adjustments. RESULTS: Two participants were randomised to each of six possible treatment orders. During automated oxygen control (n=12), the mean (±SD) time to reach target range was 114.8 (±87.9), 56.6 (±47.7) and 67.3 (±61) seconds for NHF, bilevel and CPAP, respectively, mean difference 58.3 (95% CI 25.0 to 91.5; p=0.002) and 47.5 (95% CI 14.3 to 80.7; p=0.007) seconds for bilevel and CPAP versus NHF, respectively. Proportions of time spent within target range were 68.5% (±16.3), 65.6% (±28.7) and 74.7% (±22.6) for NHF, bilevel and CPAP, respectively.Manually increasing, then decreasing, the FiO2 resulted in similar increases and then decreases in SpO2 and transcutaneous carbon dioxide (PtCO2) with NHF, bilevel and CPAP. CONCLUSION: The target SpO2 range was achieved more quickly when automated oxygen control was initiated with bilevel and CPAP compared with NHF while time spent within the range across the three therapies was similar. Manually changing the FiO2 had similar effects on SpO2 and PtCO2 across each of the three therapies. TRIAL REGISTRATION NUMBER: ACTRN12622000433707.

Management of neonates with respiratory distress syndrome in resource-limited settings.

In South Africa, prematurity stands as one of the foremost causes of neonatal mortality. A significant proportion of these deaths occur because of respiratory distress syndrome of prematurity. The implementation of non-invasive respiratory support, such as continuous positive airway pressure (CPAP), has demonstrated both safety and efficacy in reducing mortality rates and decreasing the need for mechanical ventilation. Given the absence of blood gas analysers and limited radiological services in many district hospitals, the severity of respiratory distress is often assessed through observation of the infant's work of breathing and the utilisation of bedside scoring systems. Based on the work of breathing, non-invasive therapy can be commenced timeously. While evidence supporting the use of high-flow nasal cannula as a primary treatment for respiratory distress syndrome remains limited, it may be considered as an alternative, provided that CPAP machines are available. The purpose of this article is to advocate the use of non-invasive therapy in low resource-limited settings and describe the indications, contraindications, complications, and application of CPAP therapy. This would benefit healthcare workers, especially in low-care settings and district hospitals.

Sleep health primary care clinical resource.

BACKGROUND: Obstructive sleep apnoea (OSA) and insomnia are the two most common sleep disorders and are frequent reasons for presentation in Australian general practice. OBJECTIVE: This article describes the development, content and suggested uses of the online sleep health primary care clinical resource, which provides general practitioners and other primary healthcare professionals with evidence-based information on the aetiology, assessment, management, referral and ongoing care for OSA and chronic insomnia. DISCUSSION: The Royal Australian College of General Practitioners-accepted clinical resource for the management of OSA and chronic insomnia in primary care was developed by the Australian National Centre for Sleep Health Services Research. The resource is designed to be used during consultations (eg following the steps in assessment and management and the use of online questionnaires for the assessment of OSA [Epworth Sleepiness Scale/OSA50/STOP-Bang] and insomnia [Sleep Condition Indicator/and Insomnia Severity Index]) and as an education/training tool (eg evidence on the role of continuous positive airway pressure/mandibular advancement splints for management of OSA and brief behavioural therapy for insomnia/cognitive behavioural therapy for insomnia for the management of insomnia).

Management of obstructive sleep apnoea in primary care.

BACKGROUND: Obstructive sleep apnoea (OSA) is common in the community and is increasing in prevalence. Primary care plays a pivotal role in the diagnosis and management of OSA. OBJECTIVE: This article focuses on the management options for a patient with an established diagnosis of OSA and provides a guide for driving licensing requirements. Indications for continuous positive airway pressure (CPAP) are discussed and tips provided to consider when conducting a review appointment, including trouble shooting. DISCUSSION: There are several treatment options available for patients with an established diagnosis of OSA. Selecting the optimal therapy involves aligning the symptoms and severity of OSA with the presence of comorbidities. CPAP is a highly effective therapy for symptomatic adults with moderate-to-severe OSA and for some symptomatic patients with mild OSA. Early trouble shooting of side effects and using supportive interventions increases the probability of long-term adherence, which is key to symptomatic improvement.

Exploring Heterogeneity in Cost-Effectiveness Using Machine Learning Methods: A Case Study Using the FIRST-ABC Trial.

OBJECTIVE: The aim of this study was to explore heterogeneity in the cost-effectiveness of high-flow nasal cannula (HFNC) therapy compared with continuous positive airway pressure (CPAP) in children following extubation. DESIGN: Using data from the FIRST-line support for Assistance in Breathing in Children (FIRST-ABC) trial, we explore heterogeneity at the individual and subgroup levels using a causal forest approach, alongside a seemingly unrelated regression (SUR) approach for comparison. SETTINGS: FIRST-ABC is a noninferiority randomized controlled trial (ISRCTN60048867) including children in UK paediatric intensive care units, which compared HFNC with CPAP as the first-line mode of noninvasive respiratory support. PATIENTS: In the step-down FIRST-ABC, 600 children clinically assessed to require noninvasive respiratory support were randomly assigned to HFNC and CPAP groups with 1:1 treatment allocation ratio. In this analysis, 118 patients were excluded because they did not consent to accessing their medical records, did not consent to follow-up questionnaire or did not receive respiratory support. MEASUREMENTS AND MAIN RESULTS: The primary outcome of this study is the incremental net monetary benefit (INB) of HFNC compared with CPAP using a willingness-to-pay threshold of £20,000 per QALY gain. INB is calculated based on total costs and quality adjusted life years (QALYs) at 6 months. The findings suggest modest heterogeneity in cost-effectiveness of HFNC compared with CPAP at the subgroup level, while greater heterogeneity is detected at the individual level. CONCLUSIONS: The estimated overall INB of HFNC is smaller than the INB for patients with better baseline status suggesting that HFNC can be more cost-effective among less severely ill patients.

The different roles of homocysteine metabolism in hypertension among normal-weight and obese patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea (OSA) is associated with hypertension. However, the differential mechanisms underlying OSA-related hypertension between normal-weight vs. obese patients is limited. METHODS: We studied 92 patients with OSA and 24 patients with continuous positive airway pressure (CPAP) treatment. Blood pressure (BP) was measured twice during awake and continuously monitored during sleep. Obesity was defined as body mass index ≥28 kg/m2. Serum metabolite levels were assessed by metabolomics. RESULTS: Among 59 normal-weight and 33 obese patients, 651 and 167 metabolites showed differences between hypertension and normotension or were associated with systolic and diastolic BP (SBP, DBP) after controlling confounders. These metabolites involved 16 and 12 Kyoto Encyclopedia of Genes and Genomes enrichment pathways in normal-weight and obese patients respectively, whereas 6 pathways overlapped. Among these 6 overlapping pathways, 4 were related to homocysteine metabolism and 2 were non-specific pathways. In homocysteine metabolism pathway, 13 metabolites were identified. Interestingly, the change trends of 7 metabolites associated with SBP (all interaction-p≤0.083) and 8 metabolites associated with DBP (all interaction-p≤0.033) were opposite between normal-weight and obese patients. Specifically, increased BP was associated with down-regulated folate-dependent remethylation and accelerated transsulfuration in normal-weight patients, whereas associated with enhanced betaine-dependent remethylation and reduced transsulfuration in obese patients. Similar findings were observed in ambulatory BP during sleep. After CPAP treatment, baseline low homocysteine levels predicted greater decrease in DBP among normal-weight but not obese patients. CONCLUSIONS: Mechanisms in OSA-related hypertension differ between normal-weight and obese patients, which are explained by different changes in homocysteine metabolism.

Validity, reliability, and responsiveness of the Brazilian version of the instrument World Health Organization Disability Assessment Schedule (WHODAS 2.0) for individuals with obstructive sleep apnoea.

BACKGROUND: Obstructive sleep apnoea (OSA) is a disabling health condition, and there is no disease-specific patient-reported outcome instrument to assess individuals with OSA. OBJECTIVES: To evaluate the psychometric properties of the Brazilian version of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) in individuals with OSA. METHODS: One hundred individuals with OSA responded to the WHODAS 2.0 version of 36 items, the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index (PSQI), and the 12-item health survey (SF-12). Internal consistency, convergent and discriminative validity, and responsiveness to continuous positive airway pressure (CPAP) were the psychometric properties tested. RESULTS: Cronbach's α values indicate good internal consistency (0.91 - 0.73), except for the self-care domain (α = 0.52). Convergent validity indicated an excellent correlation (r = -0.80) between the domains of functioning and quality of life. Discriminative validity showed no association between OSA severity and functioning (p = 0.90). The responsiveness to CPAP treatment showed a large effect size (r = 0.82; p < 0.05) CONCLUSIONS: The WHODAS 2.0 instrument is valid, reliable, and responsive for assessing individuals with OSA.