Breathing In Patients Research Articles

Correlations between propofol concentration in exhaled breath and BIS in patients undergoing thyroid surgery

Several clinical studies have reported promising correlations between propofol concentration in exhaled breath (Ce-pro) and the bispectral index (BIS) in patients, suggesting the potential of exhaled propofol measurement as a non-invasive method for adjusting anesthesia depth. However, these studies are still in the validation phase of instrument effectiveness, often limited by small sample sizes or inappropriate instrument selection, and thus lack convincing results regarding these correlations. In this study, one hundred patients aged 18-65, undergoing elective thyroid surgery under general anesthesia were included. The vacuum ultraviolet photoionization and time-of-flight mass spectrometry was employed to monitor Ce-pro at 20 s intervals, alongside continuous BIS measurement. The association between Ce-pro and BIS was analyzed using linear mixed-effects models, with marginalR2used to assess the correlation. The threshold of Ce-pro at awakening was also explored. Additionally, the univariate and multifactorial diagnostic model, including end-of-surgery Ce-pro, were employed to assess the accuracy of predicting delayed recovery. A weak correlation was observed between intraoperative Ce-pro and BIS (marginalR2= 0.348). Predictive models utilizing end-of-surgery Ce-pro levels showed good accuracy (area under the curve (AUC) = 0.75, 95% CI: 0.62-0.89,P= 0.003) in predicting delayed recovery, while the model using end-of-surgery Ce-pro combined with gender, sufentanil dosage, the time from the last administration of sufentanil to the end of surgery, and anesthesia duration demonstrated stronger predicting accuracy (AUC = 0.91, 95% CI: 0.85-0.98,P< 0.001). This study suggests that Ce-pro alone may not reliably predict the depth of anesthesia in clinical practice, but shows promising accuracy in predicting delayed recovery from anesthesia.

Performance of questionnaires to predict sleep-disordered breathing in acute stroke patients.

Sleep-disordered breathing is common in stroke and may negatively affect its outcome. Screening for sleep-disordered breathing in this setting is of interest but poorly studied. We aimed to evaluate the performance of eight obstructive sleep apnea screening questionnaires to predict sleep-disordered breathing in acute stroke or transient ischaemic attack patients, and to assess the impact of stroke/transient ischaemic attack-specific factors on sleep-disordered breathing prediction. We analysed acute stroke/transient ischaemic attack patients (N = 195) from a prospective cohort ("Sleep Deficiency and Stroke Outcome study"). Assessments included anthropometrics, stroke-specific parameters, sleep history, an in-hospital respiratory polygraphy within the first week after stroke, and obstructive sleep apnea screening questionnaires (Berlin Questionnaire, Epworth Sleepiness Scale, STOP-BANG, NoSAS, Sleep Apnea Clinical Score, No-Apnea, Sleep Obstructive apnea score optimized for Stroke, SLEEP-IN). In a binary classification task for respiratory event index ≥ 15 per hr, we evaluated the performance of the above-mentioned questionnaires. We used logistic regression to identify predictors for sleep-disordered breathing in this cohort. The areas under the curve for respiratory event index ≥ 15 per hr were: Berlin Questionnaire 0.60; STOP-BANG 0.72; NoSAS 0.69; No-Apnea 0.69; Sleep Apnea Clinical Score 0.75; Epworth Sleepiness Scale 0.50; Sleep Obstructive apnea score optimized for Stroke 0.58; and SLEEP-IN 0.67. The No-Apnea had the lowest false omission rate (0.13), a sensitivity of 0.97 and a specificity of 0.12. In multiple logistic regression analysis (respiratory event index ≥ 15 per hr), age, neck circumference, National Institutes of Health Stroke Scale at admission, prior stroke, cardioembolic stroke aetiology and observed apneas were associated with sleep-disordered breathing. The logistic regression model performed similar (area under the curve 0.80) to Sleep Apnea Clinical Score (p = 0.402) and STOP-BANG (p = 0.127), but outperformed the other questionnaires. Neither existing questionnaires nor our statistical model are sufficient to accurately diagnose sleep-disordered breathing after stroke, thus requiring sleep study evaluation. The No-Apnea questionnaire may help to identify patients amenable to sleep testing.

Modeling ventilation of patients with interstitial lung disease at rest and exercise: a bench study

BackgroundThe ventilatory physiopathology of patients with interstitial lung disease (ILD) remains poorly understood. We aimed to personalize a mechanical simulator to model healthy and ILD profiles ventilation, and to evaluate the effect of spontaneous breathing on respiratory mechanics at rest and during exercise.MethodsIn a 2-compartment lung simulator (ASL 5000®), we modeled 1 healthy and 3 ILD profiles, at rest and during exercise, based on physiological data from literature and patients. Measurements were: tidal volume, end-expiratory lung volume, driving pressure, transpulmonary driving pressure, dynamic alveolar strain, mechanical power, and time lag of inspiratory flow between compartments 1 and 2.ResultsHealthy and ILD models were validated: maximum differences between real and simulated tidal volume were 5% (96 ml) and 6% (54 ml) at rest and during exercise respectively, considered clinically negligible. When we simulated lung inhomogeneity (compliance in compartment 1 > compartment 2), tidal volume, end-expiratory lung volume, driving pressure and mechanical power increased in compartment 1 and decreased in compartment 2. Driving transpulmonary pressure and dynamic alveolar strain increased in compartment 2 and decreased in compartment 1. Time lag of inspiratory flow between compartments 1 and 2 was positively correlated with a difference of compliance between compartments (r = 0.98, CI95% (0.9106; 0.9962), p < 0.0001).ConclusionIn this bench study, we personalized a mechanical simulator thatmodels the lung inhomogeneity and spontaneous breathing of healthy subjects and ILD patients at rest and during exercise. Our results suggest that lung inhomogeneity could increase lung vulnerability to volo-atelec-trauma mechanisms in ILD. Further physiological studies are needed to evaluate the impact of this vulnerability on acute or chronic ILD worsening.

Personalized positive end-expiratory pressure in spontaneously breathing patients with acute respiratory distress syndrome by simultaneous electrical impedance tomography and transpulmonary pressure monitoring: a randomized crossover trial

PurposePersonalized positive end-expiratory pressure (PEEP) might foster lung and diaphragm protection in patients with acute respiratory distress syndrome (ARDS) who are undergoing pressure support ventilation (PSV). We aimed to compare the physiologic effects of personalized PEEP set according to synchronized electrical impedance tomography (EIT) and driving transpulmonary pressure (∆PL) monitoring against a classical lower PEEP/FiO2 table in intubated ARDS patients undergoing PSV.MethodsA cross-over randomized multicenter study was conducted in 30 ARDS patients with simultaneous recording of the airway, esophageal and transpulmonary pressure, together with EIT during PSV. Following a decremental PEEP trial (18 cmH2O to 4 cmH2O), PEEPEIT-∆PL was identified as the level with the smallest difference between lung overdistension and collapse. A low PEEP/FiO2 table was used to select PEEPTABLE. Each PEEP strategy was applied for 20 min, and physiologic data were collected at the end of each step.ResultsThe PEEP trial was well tolerated. Median PEEPEIT-∆PL was higher than PEEPTABLE (10 [8–12] vs. 8 [5–10] cmH2O; P = 0.021) and, at the individual patient level, PEEPEIT-∆PL level differed from PEEPTABLE in all patients. Overall, PEEPEIT-∆PL was associated with lower dynamic ∆PL (P < 0.001) and pressure–time product (P < 0.001), but there was variability among patients. PEEPEIT-∆PL also decreased respiratory drive and effort (P < 0.001), improved regional lung mechanics (P < 0.05) and reversed lung collapse (P = 0.007) without increasing overdistension (P = 0.695).ConclusionPersonalized PEEP selected using synchronized EIT and transpulmonary pressure monitoring could be associated with reduced dynamic lung stress and metabolic work of breathing in ARDS patients undergoing PSV.

Noninvasive, Multimodal Inflammatory Biomarker Discovery for Systemic Inflammation (NOVA Study): Protocol for a Cross-Sectional Study.

Prolonged systemic inflammation is recognized as a major contributor to the development of various chronic inflammatory diseases. Daily measurements of inflammatory biomarkers can significantly improve disease monitoring of systemic inflammation, thus contributing to reducing the burden on patients and the health care system. There exists, however, no scalable, cost-efficient, and noninvasive biomarker for remote assessment of systemic inflammation. To this end, we propose a novel, multimodal, and noninvasive approach for measuring inflammatory biomarkers. This study aimed to evaluate the relationship between the levels of inflammatory biomarkers in serum (gold standard) and those measured noninvasively in urine, sweat, saliva, exhaled breath, stool, and core body temperature in patients with systemic inflammation. This study is a single-center, cross-sectional study and includes a total of 20 participants (10 patients with systemic inflammation and 10 control patients). Eligible participants provide serum, urine, sweat, saliva, exhaled breath, and stool samples for biomarker analyses. Core body temperature is measured using a sensor. The primary end point is the level of C-reactive protein (CRP). The secondary end points are interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α levels. The tertiary end points are fractional exhaled nitric oxide, calprotectin, and core body temperature. Samples will be collected in 2 batches, enabling preliminary analysis of the first batch (patients 1-5 from each group). The full analysis will include both batches. CRP and cytokine levels will be measured using enzyme-linked immunosorbent assay and electrochemiluminescence immunoassay. For statistical analysis, the Shapiro-Wilk test will be used to evaluate the normality of the distribution in each variable. We will perform the 2-tailed t test or Wilcoxon rank sum test to compare the levels of inflammatory biomarkers between patients with systemic inflammations and control patients. Pearson and Spearman correlation coefficients will assess the relationship between inflammatory biomarkers from noninvasive methods and serum biomarkers. Using all-subset regression analysis, we will determine the combination of noninvasive methods yielding the highest predictive accuracy for serum CRP levels. Participants' preferences for sampling methods will be assessed through a questionnaire. The study received ethics approval from the independent research ethics committee of Canton Zurich on October 28, 2022. A total of 20 participants participated in the study measurements. Data collection started on February 22, 2023, and was completed on September 22, 2023. Participants were on average 52.8 (SD 14.4; range 24-82) years of age, and 70% (14/20) of them were women. The analysis results reporting findings are expected to be published in 2025. This study aims to evaluate the feasibility of noninvasive, multimodal assessment of inflammatory biomarkers in patients with systemic inflammation. Promising results could lead to the creation of noninvasive and potentially digital biomarkers for systemic inflammation, enabling continuous monitoring and early diagnosis of inflammatory activity in a remote setting. DERR1-10.2196/62877.

Sleep and Respiratory Parameters After Lung Transplantation in Adult Patients With Cystic Fibrosis.

We aimed to explore the prevalence and predictive factors of sleep-disordered breathing (SDB) in patients with cystic fibrosis (pwCF) after lung transplantation (LTX). We prospectively recruited adult pwCF who underwent LTX in our hospital from 2013 to 2022 and invited them for an attended overnight polysomnography (PSG) 1year after transplantation. The apnea-hypopnea index (AHI) was the primary outcome, and SDB was defined as an AHI≥5. Demographic, anthropometric, cardiometabolic, drug treatment, and pulmonary function variables were compared between pwCF with and without SDB. Multiple regression analysis was used to identify significant predictors of SDB. For a subset of participants who had available PSG before transplantation, sleep parameters were compared pre-post transplantation. Sixty-two pwCF (31 females) were enrolled. Thirty participants had SDB, but only 11 of them had moderate-to-severe SDB (AHI≥15). The average Epworth Sleepiness Scale (ESS) score indicated the absence of excessive daytime sleepiness. Older age (p<0.001), male sex (p<0.001), and smaller thoracic gas volume (p=0.002) significantly predicted higher AHI. Comparison between pre- and post-transplantation polysomnographic data showed a significant increase in the percentage of slow wave sleep (p=0.047), as well as a significant improvement in mean nocturnal oxygen saturation (p=0.007). A statistically significant increase in the AHI was also observed (p=0.047), but its clinical importance is uncertain (p=0.476 for the increase in the ESS score). We may conclude that SDB is prevalent in pwCF after LTX, but its severity is mild. Older male pwCF with greater improvement in lung hyperinflation after transplantation might be at risk for SDB and should be followed for symptoms or signs of sleep apnea.

Effects of phrenic nerve magnetic stimulation on respiratory function in stroke patients: study protocol for a randomised controlled trial.

Respiratory dysfunction is a notable complication in stroke patients, in which the diaphragm, as the primary respiratory muscle, directly influences lung function. Repetitive peripheral magnetic stimulation (rPMS) is a new, non-invasive approach that is used to treat brain and nerve problems. Few studies have examined the effect of magnetic stimulation on the phrenic nerve, breathing and diaphragm in stroke patients. This study aims to assess the effect of magnetic phrenic nerve stimulation on respiratory muscle function and lung function in adults with stroke. The results of this study may provide a promising approach to managing respiratory dysfunction in stroke patients. This randomised controlled trial is designed to compare the effectiveness of bilateral magnetic phrenic nerve stimulation (rPMS) and conventional rehabilitation training in enhancing respiratory muscle strength, lung function indicators, diaphragmatic excursion and diaphragm thickness in patients with respiratory muscle weakness. Thirty patients admitted to the First Hospital of Fujian Medical University will be included in this study. Participants in the intervention group will undergo daily bilateral magnetic phrenic nerve stimulation for 2 weeks. Stimulation will be administered at a frequency of 25 Hz, with a pulse duration of 1.1 s and an inter-pulse interval of 5.9 s, for 5 days each week. Primary outcome measures will be assessed at baseline and after 2 weeks (end of the intervention) to evaluate the efficacy of rPMS compared with conventional rehabilitation techniques. Before commencing the study, all participants will receive a comprehensive explanation of the study procedures, including the assessments. They will also be provided informed consent forms for review, completion and signing. This study was approved by the Ethics Committee for Research at the First Affiliated Hospital of Fujian Medical University (No.: MRCTA, ECFAH of FMU [2021]641, dated 10 November 2023) (Appendix Ⅰ & Ⅱ). The trial protocol will strictly adhere to the Uniform Standards for Reporting of Trials (CONSORT) statement. The trial has been registered with the Chinese Clinical Trial Registry.Dissemination of individual findings for each participant will be available at the end of the study. The findings will be disseminated to different interest groups, participants or other patients with respiratory dysfunction through journal papers and/or conference presentations. The results of the primary trial will be submitted for publication in a peer-reviewed journal. ChiCTR2300075669, registered on 12 September 2023.

Theoretical Study of Gas Sensing toward Acetone by a Single-Atom Transition Metal (Sc, Ti, V, and Cr)-Doped InP3 Monolayer.

Acetone (C3H6O) gas in the exhaled breath of diabetic patients can be used as an important biomarker for the painless and noninvasive diagnosis of diabetes mellitus. In this paper, based on the density functional theory (DFT), the adsorption behaviors of pristine and single-atom transition metal (X = Sc, Ti, V, and Cr)-doped InP3 surfaces (denoted as X-InP3) toward C3H6O molecule were examined to explore the potential of these two-dimensional (2D) materials as a sensitive sensor for acetone gas. The calculation results indicate the unfavorable detection property for the pristine 2D-InP3 surface upon acetone with an unsatisfied gas response (12.4%). The introduction of a single-atom transition metal (Sc, Ti, V, and Cr) into the InP3 layer has significantly improved the adsorption capacity toward the C3H6O molecule. Owing to the high gas response values (-98.0%, 393.3%, and 393.3%), the Ti-InP3, V-InP3, and Cr-InP3 layers show their superiority in C3H6O detection at room temperature, in which Ti-InP3 achieves recycle use through heating at 698 K. Sc-InP3 is unsuitable for C3H6O sensing with a poor response (8.1%). Our work first gives a theoretical predication about the adsorption and sensitive detection performance of pristine and single-atom transition metal (Sc, Ti, V, and Cr)-doped InP3 upon acetone, which may provide an emerging kind of sensing material for the noninvasive diagnosis of diabetes mellitus indicated by acetone gas.

Bispectral Index Guidance Reduced Target Plasma Propofol Concentration During ERCP in Patients with Liver Cirrhosis.

The primary aim of this study was to investigate the guidance effect of the bispectral index (BIS) on the target plasma concentration (TPC) of propofol required for deep sedation during endoscopic retrograde cholangiopancreatography (ERCP). Second, to identify propofol consumption, recovery time, and adverse events. A total of 42 consecutive patients with liver cirrhosis and 43 consecutive patients with healthy livers were enrolled. Propofol was administered via a target control infusion (TCI) syringe pump (Marsh Model) at BIS 60-70. Patients were not intubated, were placed in the prone position, and underwent spontaneous breathing. Propofol TPCs (μg mL-1) and BIS values were recorded at T0 (baseline), T1 (5 min after induction), T2 (5 min into ERCP), T3 (15 min), T4 (30 min), and T5 (recovery). TPCs and propofol consumption were lower in patients with cirrhosis than in those without cirrhosis (T4: 2.7±0.5 vs. 3.3±0.4 μg mL-1), P=0.001, and 270.4±6.9 mg vs. 390.8±13.4 mg, P=0.001), respectively. Patients with cirrhosis required more time to recover (8.5±2 vs. 6.2±0.9 min, P=0.001), despite comparable ERCP durations (31.1±11.1 vs. 34±12.5 min, P=0.28). A significant decline in TPC values among patients with cirrhosis with time (T1: 3.3±0.3, T2: 3.1±0.3, T3: 2.9±0.4, T4: 2.7±0.5 μg mL-1, P=0.001), indicating a cumulative effect. One patient with cirrhosis required bag-mask ventilation, while three patients without cirrhosis were converted to general anaesthesia. Combining the TCI Marsh pharmacokinetic model with BIS monitoring lowered the TPC levels required for deep sedation in patients with cirrhosis compared with healthy patients and allowed for individual variations. The prone position in deeply sedated and non-intubated spontaneous breathing patients is not without the risk of hypoxia.

Sleep disordered breathing and in-hospital prognosis in acute myocardial infarction patients: a subset of the AMI-Sleep study

Abstract Background Despite its high prevalence in patients with coronary artery disease (CAD), the association between sleep disordered breathing (SDB) and in-hospital prognosis is not well determined. Purpose We aimed to study in-hospital prognosis depending on the presence of SDB in patient hospitalized for acute myocardial infarction (AMI). Methods We prospectively enrolled a subset of patients hospitalized for AMI of the French Cohort of Myocardial Infarction Evaluation (FRENCHIE) registry included from January 2019 and December 2022 in the 16 AMI-Sleep-trained centers. Baseline and in-hospital information were collected through the FRENCHIE registry. A simplified polygraphy through ApneaLink Air+ was performed overnight during the initial hospitalization before discharge. Data were scored in centralized manner at a single center where trained physicians ascertained SDB severity based on Apnea-Hypopnea index (AHI). SDB screening was considered as positive for patients who have at least moderate SDB, defined by an AHI≥15/h. Results Among 1752 patients, 955 (54.5 [52.1;56.9] %) had at least moderate SDB. Compared with patients without SDB, SDB patients have major cardiac impairment including more 3-vessel CAD (26.8% vs 20.8%) and a lower admission left ventricular ejection fraction (52.2% vs 50.4%) associated with a higher use of non-invasive ventilation (3.8% vs 1.6% in non-SDB patients). SDB patients had also more in-hospital complications in particular more transfer to hospital intensive care (0.1% vs 0.9%) and an increased length of stay (4.8 vs 5.9 days). Conclusion More than half of the patients hospitalized for AMI had at least moderate SDB and presence of SDB was associated with more in-hospital morbidity. SDB screening should be considered to identify high risk sub-group of AMI patients.

Prevalence, type, severity and determinants of sleep disordered breathing in acute myocardial infarction patients: the AMI-Sleep study

Abstract Background Sleep Disordered Breathing (SDB) is highly prevalent in patients with ischemic heart disease and often remains undiagnosed. Purpose We aimed to assess the prevalence, type, severity and determinants of SDB in patient hospitalized for acute myocardial infarction (AMI). Methods We prospectively enrolled a subset of patients hospitalized for AMI of the French Cohort of Myocardial Infarction Evaluation (FRENCHIE) registry included from January 2019 and December 2022 in the 16 AMI-Sleep-trained centers. Baseline and in-hospital information were collected through the FRENCHIE registry. A simplified polygraphy through ApneaLink Air+ was performed overnight during the initial hospitalization before discharge. Data were scored in centralized manner at a single center where trained physicians ascertained SDB characteristics (central or obstructive) and severity based on Apnea-Hypopnea index (AHI). SDB was defined by an AHI≥15/h. Multivariable logistic regression (adjusted for age, sex, diabetes, hypertension, smoking, body mass index, severity of the coronary artery disease, left ventricular ejection fraction [LVEF] at admission [or at discharge if missing] and use of Ticagrelor) was used to analyze the associations between characteristics of the patients at inclusion and SDB. Results Among 1752 patients, 955 (54.5 [52.1;56.9] %) had an AHI≥15/h. The prevalences of mild (AHI= 5-14.9), moderate (AHI=15-29.9) and severe (AHI≥30) SDB were 30.9%, 24.2% and 30.3% respectively. SDB characterization was technically possible in 712 patients (74.6%), and was found central in 72.2% of cases, obstructive in 12.9% and mixed in 15.4%. Male sex, age, BMI, diabetes, degree of severity of CAD, LVEF≤40% and treatment with Ticagrelor were independently associated with SDB. Conclusion More than half of the patients hospitalized for AMI had at least moderate SDB with a majority of them characterized as central. SDB diagnosis should be considered in this setting and particularly in very high cardiovascular risk patients with severe CAD.SDB determinants in AMI patients

Semi-automatic robotic puncture system based on deformable soft tissue point cloud registration.

Traditional surgical puncture robot systems based on computed tomography (CT) and infrared camera guidance have natural disadvantages for puncture of deformable soft tissues such as the liver. Liver movement and deformation caused by breathing are difficult to accurately assess and compensate by current technical solutions. We propose a semi-automatic robotic puncture system based on real-time ultrasound images to solve this problem. Real-time ultrasound images and their spatial position information can be obtained by robot in this system. By recognizing target tissue in these ultrasound images and using reconstruction algorithm, 3D real-time ultrasound tissue point cloud can be constructed. Point cloud of the target tissue in the CT image can be obtained by using developed software. Through the point cloud registration method based on feature points, two point clouds above are registered. The puncture target will be automatically positioned, then robot quickly carries the puncture guide mechanism to the puncture site and guides the puncture. It takes about just tens of seconds from the start of image acquisition to completion of needle insertion. Patient can be controlled by a ventilator to temporarily stop breathing, and patient's breathing state does not need to be the same as taking CT scan. The average operation time of 24 phantom experiments is 64.5 s, and the average error between the needle tip and the target point after puncture is 0.8mm. Two animal puncture surgeries were performed, and the results indicated that the puncture errors of these two experiments are 1.76mm and 1.81mm, respectively. Robot system can effectively carry out and implement liver tissue puncture surgery, and the success rate of phantom experiments and experiments is 100%. It also shows that the puncture robot system has high puncture accuracy, short operation time, and great clinical value.

Impact of low dose inhaled nitric oxide treatment in spontaneously breathing and intubated COVID-19 patients: a retrospective propensity-matched study

BackgroundThe benefit of Inhaled nitric oxide (iNO) therapy in the setting of COVID-19-related ARDS is obscure. We performed a multicenter retrospective study to evaluate the impact of iNO on patients with COVID-19 who require respiratory support.MethodsThis retrospective multicenter study included COVID-19 patients enrolled in the SCCM VIRUS COVID-19 registry who were admitted to different Mayo Clinic sites between March 2020 and June 2022 and required high-flow nasal cannula (HFNC), non-invasive ventilation (NIV), or invasive mechanical ventilation (IMV). Patients were included in the ‘spontaneously breathing’ group if they remained non-intubated or were initiated on an HFNC (± NIV) before intubation. Patients who got intubated without prior use of an HFNC (± NIV) were included in the ‘intubated group.’ They were further divided into categories based on their iNO usage. Propensity score matching (PSM) and inverse propensity of treatment weighting (IPTW) were performed to examine outcomes.ResultsAmong 2767 patients included in our analysis, 1879 belonged to spontaneously breathing (153 received iNO), and 888 belonged to the intubated group (193 received iNO). There was a consistent improvement in FiO2 requirement, P/F ratio, and respiratory rate within 48 h of iNO use among both spontaneously breathing and intubated groups. However, there was no significant difference in intubation risk with iNO use among spontaneously breathing patients (PSM OR 1.08, CI 0.71–1.65; IPTW OR 1.10, CI 0.90–1.33). In a time-to-event analysis using Cox proportional hazard model, spontaneously breathing patients initiated on iNO had a lower hazard ratio of in-hospital mortality (PSM HR 0.49, CI 0.32–0.75, IPTW HR 0.40, 95% CI 0.26–0.62) but intubated patients did not (PSM HR: 0.90; CI 0.66–1.24, IPTW HR 0.98, 95% CI 0.73–1.31). iNO use was associated with longer in-hospital stays, ICU stays, ventilation duration, and a higher incidence of creatinine rise.ConclusionsThis retrospective propensity-score matched study showed that spontaneously breathing COVID-19 patients on HFNC/ NIV support had a decreased in-hospital mortality risk with iNO use in a time-to-event analysis. Both intubated and spontaneously breathing patients had improvement in oxygenation parameters with iNO therapy but were associated with longer in-hospital stays, ICU stays, ventilation duration, and higher incidence of creatinine rise.

Waveguide-Based Microwave Nitric Oxide Sensor for COVID-19 Screening: Mass Transfer Modulation Effect on Hollow Confined WO3 Structures.

Serious acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses a tremendous threat to global public health. Recently, the Food and Drug Administration approved the emergency use of volatile organic components as detection biomarkers for COVID-19, ushering in a new era of portable, simple, and rapid epidemiological screening based on breath diagnosis. Nitric oxide (NO) is an important biomarker indicating the degree of inflammation in the respiratory tract. In this study, a hollow multishelled structured WO3 (HoMSs-WO3)-based waveguide microwave gas sensor (MGS) was fabricated to detect trace levels of NO in exhaled breath for the preliminary diagnosis of COVID-19. The sensor showed excellent reusability and selectivity and efficiently detected NO in the 10-100 ppb, with a sensitivity of 39.27 dB/ppm and a detection limit of 2.52 ppb. In addition, a sound correlation was observed in the measurement results between the MGS and the Sunvou detector for detecting NO from the exhaled breath of clinical COVID-19 patients. The difference between the two measurements was within 1.96 standard bias, and the consistency range was -12 to 17 ppb, thus fully demonstrating the significant potential of the sensor in COVID-19 screening.

Prehospital Trauma Compendium: Traumatic Pneumothorax Care – a position statement and resource document of NAEMSP

ABSTRACT Emergency Medical Services (EMS) clinicians manage patients with traumatic pneumothoraces. These may be simple pneumothoraces that are less clinically impactful, or tension pneumothoraces that disturb perfusion, lead to shock, and impart significant risk for morbidity and mortality. Needle thoracostomy is the most common EMS treatment of tension pneumothorax, but despite the potentially life-saving value of needle thoracostomy, reports indicate frequent misapplication of the procedure as well as low rates of successful decompression. This has led some to question the value of prehospital needle thoracostomy and has prompted consideration of alternative approaches to management (e.g., simple thoracostomy, tube thoracostomy). EMS clinicians must determine when pleural decompression is indicated and optimize the safety and effectiveness of the procedure. Further, there is also ambiguity regarding EMS management of open pneumothoraces. To provide evidence-based guidance on the management of traumatic pneumothoraces in the EMS setting, NAEMSP performed a structured literature review and developed the following recommendations supported by the evidence summarized in the accompanying resource document. NAEMSP recommends: EMS identification of a tension pneumothorax must be guided by a combination of risk factors and physical findings, which may be augmented by diagnostic technologies. EMS clinicians should recognize the differences in the clinical presentation of a tension pneumothorax in spontaneously breathing patients and in patients receiving positive pressure ventilation. EMS clinicians should not perform pleural decompression in patients with simple pneumothoraces but should perform pleural decompression in patients with tension pneumothorax, if within the clinician’s scope of practice. When within scope of practice, EMS clinicians should use needle thoracostomy as the primary strategy for pleural decompression of tension pneumothorax in most cases. EMS clinicians should take a patient-individualized approach to performing needle thoracostomy, influenced by factors known to impact chest wall thickness and risk for iatrogenic injury. Simple thoracostomy and tube thoracostomy may be used by highly trained EMS clinicians in select clinical settings with appropriate medical oversight and quality assurance. EMS systems must investigate and adopt strategies to confirm successful pleural decompression at the time thoracostomy is performed. Pleural decompression should be performed for patients with traumatic out-of-hospital circulatory arrest (TOHCA) if there are clinical signs of tension pneumothorax or suspicion thereof due to significant thoraco-abdominal trauma. Empiric bilateral decompression, however, is not routinely indicated in the absence of such findings. EMS clinicians should not routinely perform pleural decompression of suspected or confirmed simple pneumothorax prior to air-medical transport in most situations. EMS clinicians may consider placement of a vented chest seal in spontaneously breathing patients with open pneumothoraces. In patients receiving positive pressure ventilation who have open pneumothoraces, chest seals may be harmful and are not recommended. EMS physicians play an important role in developing curricula and leading quality management programs to both ensure that EMS clinicians are properly trained in the recognition and management of tension pneumothorax and to ensure that interventions for tension pneumothorax are performed appropriately, safely, and effectively.

Prevalence and assessment of sleep-disordered breathing in head and neck cancer patients: a systematic review.

Sleep-disordered breathing (SDB) is a very common and underdiagnosed condition in head and neck cancers (HNC) patients. If untreated, SDB can lead to negative health consequences. The identification of SDB in HNC patients is crucial to ensure appropriate treatment and to improve outcomes. The purpose of the study was to investigate the incidence of coexisting SDB in HNC patients and to evaluate methods of assessing SDB in the population. A systematic search of PubMed, Embase, CINAHL, Cochrane Database, the Web of Science, and Scopus was performed for studies related to SDB in HNC patients. In total, 1713 articles were identified. 19 articles were selected for qualitative synthesis. The studies involved 584 subjects. The prevalence of SDB ranged from 57 to 90% before cancer treatment and from 12 to 96% after. When using an apnea-hypopnea index (AHI) cut-off ≥ 5/h to diagnosis SDB, the prevalence of SDB was 57-90% before cancer treatment and 12-94% after treatment. Sleep studies using polysomnography are the most commonly used assessment tools, but thresholds for diagnosis have been inconsistent. There is a high prevalence of SDB in HNC patients. However, the diagnostic and thresholds methods used for detecting SDB vary widely. To determine the accurate prevalence of SDB, prospective, systematic studies of SDB in unselected cohorts of HNC participants are required.

Upper airway resistance during use of a laryngeal mask airway is flow-dependent and dominated by the laryngeal resistance

During use of a laryngeal mask airway, resistance of the device and larynx contribute to the upper airway resistance. Detailed understanding of this combined resistance is crucial to support spontaneously breathing patients appropriately or to take the right measures during respiratory problems. However, their resistive behavior and which of these components determine the upper airway resistance predominantly, has not been characterized systematically. Pressure-flow-relationships of different sizes of a laryngeal mask airway, of a laryngeal model with vocal cord angles between 10° and 60° and of the combination of a laryngeal mask airway size 4 and the laryngeal model were measured. Results were fitted to the expanded Rohrer’s equation and resistances were calculated. The laryngeal mask airway and the laryngeal model showed a nonlinear flow-dependent resistive behavior. Decreasing size of the laryngeal mask airway, decreasing vocal cord angles, and increasing flow rates resulted in increased resistances (all p < 0.001). Resistance of the laryngeal mask and the laryngeal model added up to the combined resistance in a summative way, where the vocal cord angle determines 59–98% of the combined resistance in adults. The upper airway resistance during the use of a laryngeal mask airway is a summative resistance with a flow-dependent, nonlinear behavior. Upper airway resistance in adults is primarily determined by the vocal cord angle during use of a laryngeal mask.

Tachypnea in response to hypoxemia decreases with age in older patients.

To investigate if tachypneic response to hypoxia is decreased in older patients. We included all patients ≥65 years of age attending 52 Spanish emergency departments (EDs) for whom peripheral arterial oxygen saturation (SatO2) measured by pulsioxymetry and respiratory rate (RR) were registered at ED arrival. We assessed the relationship between SatO2 and RR in different models, and with the best-fitting model, we independently analyzed this relationship in four subgroups according to patient age (65-69, 70-79, 80-89, and ≥90 years). Five sensitivity analyses using different subsets of patients were carried out to check for the consistency of the results. We included 7126 patients, with medians for SatO2 and RR of 97% (interquartile range [IQR]: 94-98) and 15 bpm (IQR: 15-16), respectively. We found significant associations (P < 0.001) between SatO2 and RR in every model tested (P < 0.001 for all), with the quadratic model obtaining the best fit (R2: 0.098) over those obtained with linear (R2: 0.096) and logarithmic (R2: 0.092) models. The same was observed in sensitivity analyses, with R2 for quadratic models ranging from 0.069 in patients with low comorbidity and 0.102 in patients breathing room air. The mean RR for 100% SatO2 was 15 bpm and increased as SatO2 decreased, although with a progressive slowing of the slope, with a mean RR of 27 at 50% SatO2. We detected a decreased RR response to increasing hypoxemia according to age and, while the RR curve was higher and with a progressively steepening slope in the 972 patients aged 65-69 (mean RR of 42 bpm with 50% SatO2), a progressive slowing of slope was observed in the 2693 patients aged 70-79 (mean RR of 28 with 50% SatO2), the 2582 aged 80-89 (mean RR of 25) and the 879 aged ≥90 (mean RR of 23). Sensitivity analyses provided very similar results. Tachypneic response to hypoxemia in older patients decreases as age advances, regardless of the reason leading to hypoxemia. Geriatr Gerontol Int 2024; 24: 1120-1129.

Estimation of transpulmonary driving pressure using a lower assist maneuver (LAM) during synchronized ventilation in patients with acute respiratory failure: a physiological study

BackgroundWe previously showed in animals that transpulmonary driving pressure (PL) can be estimated during Neurally Adjusted Ventilatory Assist (NAVA) and Neural Pressure Support (NPS) using a single lower assist maneuver (LAM). The aim of this study was to test the LAM-based estimate of PL (PL_LAM) in patients with acute respiratory failure.MethodsThis was a prospective, physiological, and interventional study in intubated patients with acute respiratory failure. During both NAVA and simulated NPS (high and low levels of assist), a LAM was performed every 3 min by manually reducing the assist to zero for one single breath (by default, ventilator still provides 2 cmH2O). Following NAVA and NPSSIM periods, patients were sedated and passively ventilated in volume control and pressure control ventilation, to obtain PL during controlled mechanical ventilation (PL_CMV). PL using an esophageal balloon (PL_Pes) was also compared to PL_LAM and PL_CMV. We measured diaphragm electrical activity (Edi), ventilator pressure (PVent), esophageal pressure (Pes) and tidal volume. PL_LAM and PL_Pes were compared to themselves, and to PL_CMV for matching flows and volumes.ResultsTen patients were included in the study. For the group, PL_LAM was closely similar to PL_CMV, with a high correlation (R2 = 0.88). Bland–Altman analysis revealed a low Bias of 0.28 cmH2O, and 1.96SD of 5.26 cmH2O. PL_LAM vs PL_Pes were also tightly related (R2 = 0.77).ConclusionThis physiological study in patients confirms our previous pre-clinical data that PL_LAM is as good an estimate as PL_Pes to determine PL, in spontaneously breathing patients on assisted mechanical ventilation.Trial registration The study was registered at clinicaltrials.gov (ID NCT05378802) on November 6, 2021

Volatile Organic Compounds (VOC) and Serum Leukotriene B4 between COPD Patients and COPD with Lung Cancer Patients

Introduction: Chronic obstructive pulmonary disease (COPD) is estimated to become the third leading cause of death worldwide in 2030. COPD can affect the lungs and cause chronic systemic inflammation. Leukotriene B4 (LTB4) is involved in COPD and lung cancer pathogenesis. There has been the development of non-invasive methods for detecting lung disease in the last few decades, such as the examination of volatile organic compounds (VOC). This study aimed to analyze the serum LTB4 and the difference of VOCs in exhaled breath of stable COPD patients and COPD with lung cancer patients. Methods: This case-control study recruited 20 stable COPD patients and 20 patients with COPD and lung cancer. An exhaled breath sample was collected in Tedlar bags and analyzed using an arrayed sensor breath analyzer to check the concentration of VOCs. Meanwhile, a venous blood sample was collected to examine the level of LTB4 using an ELISA kit. Independent t-test and Mann-Whitney test were used to analyze the data. Results: The carbon dioxide (CO2), nitrogen dioxide (NO2), carbon monoxide (CO), benzene (C6H6), and propane (C3H8) levels were significantly different (p &lt;0.05) in COPD-only patients compared to COPD with lung cancer patients. Serum LTB4 increased in both groups. Conclusion: CO2, CO, and C3H8 levels increased, but the NO2 level decreased in COPD patients with lung cancer compared to COPD-only patients. Serum LTB4 increased in COPD with lung cancer patients.