Respiratory care最新文献

Background: Patients with interstitial lung disease (ILD) and hypoxemia often require long-term home-based oxygen therapy. A demand oxygen delivery system (DODS), which is particularly useful during outdoor activities, requires careful evaluation regarding its effectiveness for alleviating hypoxemia, particularly during exertion. OxyCube, a DODS with a built-in second tank, was designed to deliver precisely adjusted oxygen pressure during inspiration. This study aimed to quantitatively compare the efficacy of OxyCube with a nontank DODS in ILD subjects who experienced exertional hypoxemia.

Methods: In this randomized crossover trial, 9 ILD subjects with hypoxemia (S_pO2 < 90%) during a 6-min walk test (6MWT) performed ergometer exercise loads under a fixed flow setting 3 times. The initial test was used to determine the maximal oxygen uptake (V˙_O2max) of each subject. A subsequent comparative test used 80% of the maximum load, alternating between the OxyCube and a sham device. The primary end point was the change in S_pO2 from the baseline (ΔS_pO2).

Results: OxyCube consistently showed a significantly lower reduction in S_pO2 than the sham device during exercise, with the most considerable difference being at the 6MWT (6.3 ± 3.0% vs 9.7 ± 3.0%, P < .01). No significant differences in ΔHR and ΔBorg score between the devices underscored the quantitative approach of the study.

Conclusions: OxyCube improved exertional hypoxemia in subjects with ILD compared with the sham device. These findings suggest that OxyCube may offer benefits for patients with ILD showing hypoxemia during exertion, although a larger study is required to validate the efficacy.

Background: COPD is a significant public health issue that negatively impacts quality of life and is associated with high mortality and morbidity rates. Although pressurized metered dose inhalers (pMDIs) are widely used in the treatment of COPD, individuals with COPD often have errors in technique. Individuals' perceptions of the disease and their reactions can influence their health behaviors and medication adherence. This study was designed to investigate the relationship between pMDI use skill and COPD perception and reaction in individuals with COPD.

Methods: This descriptive and correlational study was conducted with 184 subjects treated at the Pulmonary Diseases Clinic. The Participants Information Form, the pMDI Skill Assessment Checklist, and the COPD Perception and Reaction Scale (COPD PRS) were used to collect data. Pearson correlation analysis was used to analyze the relationship between subjects' pMDI skill scores and their COPD PRS scores. The variables predicting COPD perception and reactions were identified using a multiple linear regression model. A P value < .05 was considered significant in all analyses.

Results: Most subjects (79%) were male with a mean age of 64.8 ± 9.6 years. The mean pMDI skill score was 3.3 ± 1.4, and the mean COPD PRS was 77.2 ± 19.5. There was a moderate, meaningful negative correlation between pMDI skill score and COPD PRS score (r = -0.69, P < .001). pMDI skill score (β = -0.36, P < .001), age (β = 0.21, P = .005), COPD duration (β = 0.19, P = .004), and systemic disease (β = 0.17, P = .004) were significant predictors of COPD perception and reaction.

Conclusions: This study suggests that assessing pMDI use skills, disease perception, and reaction in individuals with COPD should become routine practice, enabling the planning of personalized educational interventions.

Background: The new global definition of nonintubated subjects with ARDS can be applied to patients receiving high-flow nasal cannula (HFNC), but stratification with P_aO2/F_IO2 has not been validated. We aimed to investigate the differences in oxygenation assessment between HFNC and CPAP for predicting outcomes.

Methods: We performed a post hoc analysis of a multi-center randomized controlled trial conducted in Japan, focusing on oxygenation assessments in subjects receiving HFNC or CPAP. Subjects with P_aO2/F_IO2 < 300 on CPAP at 5 cm H₂O were assigned to receive either HFNC or CPAP. Subjects were stratified into mild (P_aO2/F_IO2 ≥ 200 but <300), moderate (P_aO2/F_IO2 ≥ 100 but < 200), or severe (P_aO2/F_IO2 < 100) hypoxemia categories based on oxygenation levels during CPAP at 5 cm H₂O. The primary outcome was treatment failure (intubation or in-hospital death). Discriminative performance for treatment failure was evaluated using the area under the receiver operating characteristic curve (AUROC) for each device.

Results: Of the 85 subjects analyzed, 31, 48, and 6 were classified as having mild, moderate, and severe hypoxemia, respectively. Treatment failure occurred more frequently in subjects with moderate and severe hypoxemia than in those with mild hypoxemia (mild 1/31 [3.2%], moderate: 12/48 [25.0%], severe: 3/6 [50.0%], P = .004). Compared with 1 of 38 subjects (2.6%) treated with CPAP, 21 of 47 subjects (44.7%) with HFNC experienced worsened oxygenation even after 30 min of treatment (P < .001). Subjects with HFNC had a lower AUROC of P_aO2/F_IO2 for treatment failure (0.66, 95% CI 0.54-0.79) than those with CPAP (0.82, 95% CI 0.74-0.90, P = .041).

Conclusions: P_aO2/F_IO2-based stratification may help predict treatment failure in patients with nonintubated subjects with ARDS. However, a thorough oxygenation assessment is necessary because of the variability introduced by different respiratory support devices. CPAP might be superior to HFNC when predicting treatment failure.

Background: Unplanned extubations (UEs) are a common adverse event among neonatal patients and can be associated with significant morbidity. Our level IV neonatal intensive care unit (NICU) UE rate was 1.33 events/100 ventilator days, which exceeded published rates. In response, our interdisciplinary quality improvement (QI) team developed targeted interventions aiming to reduce the institutional UE rate to be in alignment with the published Solutions for Patient Safety centerline (0.6 events/100 ventilator days).

Methods: Baseline UE events in the pre-intervention period (2020 and 2021) were compared with events after implementation of interventions (2022 and 2023). Targeted interventions were implemented via Plan-Do-Study-Act cycles and included a formalized UE huddle process, leadership rounding, Kamishibai cards to measure UE bundle adherence, standardized endotracheal tube (ETT) securement process, and annotated ETT depth on chest radiographs. The primary outcome measure was UE rate (events/100 ventilator days). Additional process measures included tracking UE bundle adherence and contributing cause event analysis.

Results: In the preintervention period, 2020 and 2021, 100 and 87 UE events were recorded, respectively. One year after implementation of the first interventions (2022), events decreased to 48 with an additional decrease to 35 in 2023. When comparing 2023 with 2020, a 65% reduction in annual UE events was noted with a centerline shift from 1.33 to 0.77/100 ventilator days.

Conclusions: Utilizing QI methodology to drive interventions significantly reduced annual UE events and rate in a level IV NICU. Standardized practices, interdisciplinary collaboration, and thorough discussion highlighting the preventability of UE events were critical to this project's success.

Background: Neurally Adjusted Ventilatory Assist (NAVA) is a patient-triggered ventilatory mode requiring intact respiratory drive. We compared 2 intravenous morphine infusion doses in infants with acute viral bronchiolitis receiving NAVA. The objectives were, to evaluate (1) impact on neural respiratory drive, measured by electrical activity of the diaphragm (EA_di) and estimated airway occlusion pressure (P_0.1) and (2) tolerability, via the COMFORT behavioral scale and physiological variables.

Methods: Randomized, nonblinded, crossover (morphine dose), feasibility trial. Infants likely requiring mechanical ventilation for >48 h at enrollment received intravenous morphine infusion rates of 5 μg/kg/h (low dose) and 20 μg/kg/h (standard dose) on alternate days, via a randomized crossover design. On each day, a combination of 16 ventilatory settings were used, incorporating differing NAVA, PEEP and pressure support levels.

Results: Thirteen participants received the intervention. The primary outcome, peak EA_di did not differ between morphine groups (P = .27), with an overall average of 12.2 ± 7.0 μV. The mean P_0.1 was higher during low-dose morphine (1.14 vs 0.89 cm H₂O, mean difference .25 cm H₂O, 95% CI 0.12-0.39, P = .002). The low-dose group exhibited higher mean heart rates (123 vs 113 beats/min, mean difference 9.9 beats/min, 95% CI 5.2-14.6, P < .001), systolic blood pressures (90 vs 86 mm Hg, mean difference 3.9 mm Hg, 95% CI 0.4-7.5, P < .001), and COMFORT-B scores, (13.7 vs 13.2, mean difference 0.5, 95% CI 0.1-1.0, P = .03). Low-dose morphine was associated with lower transcutaneous CO₂ levels (37 vs 43 mm Hg, mean difference 6 mm Hg, 95% CI 3.9-8.4 mm Hg, P < .001), despite no difference in between-group breathing frequency (P = .11), tidal volume (P = .16) or minute ventilation (P = .33).

Conclusions: Intravenous morphine at 20 μg/kg/h did not blunt neural respiratory drive during NAVA and appeared more favorable than 5 μg/kg/h in terms of tolerability. This may inform a larger trial evaluating NAVA in bronchiolitis.

Mechanical ventilation management remains one of the most complex and critical interventions in intensive care medicine. As ventilation strategies continue to evolve from gas exchange optimization to comprehensive lung and diaphragm protection, the cognitive burden on clinicians has increased substantially. Decision assist systems represent a promising technological advancement that can help bridge the gap between evidence-based protocols and individualized patient care. Unlike fully automated closed-loop systems, decision assist tools maintain clinician oversight while providing real-time, data-driven recommendations to optimize ventilator management. This narrative review examines the current landscape of decision assist systems in mechanical ventilation, exploring their potential benefits in improving health equity, reducing practice variation, and enhancing adherence to protective ventilation strategies. We discuss the technical challenges, implementation barriers, and future directions for these systems, with particular emphasis on balancing the competing priorities of lung protection and diaphragm preservation. We illustrate these principles using examples from the development and implementation of a decision assist system called REDvent (real-time effort driven ventilator management) which was recently tested in a phase 2 clinical trial. While fully automated ventilation remains challenging due to the complexity of clinical decision-making and the need for contextual judgment, decision assist systems offer a pragmatic approach to improving ventilator management in the contemporary intensive care unit.

Background: Community-based pulmonary rehabilitation (PR) programs preserve essential PR elements such as exercise, disease education, and social support while addressing barriers to cost and transportation by offering low equipment options and flexible location delivery. We evaluated the feasibility of a 10-week community-based PR program, COPD Wellness, with and without Health Advocates (HA), who assist with unmet social needs in patients with COPD receiving care within a safety-net health care setting.

Methods: In this single-center feasibility study (September 2017 to January 2020), participants with moderate-to-severe COPD were randomized to COPD Wellness alone or with HA support. The program included 10 weekly supervised 90-min sessions. Feasibility outcomes included recruitment rates, attendance, and adherence (≥6 sessions). Clinical outcomes included COPD Assessment Test (CAT) scores, 6-min walk distance (6MWD), depressive symptoms (PHQ-8), and exacerbation, analyzed using paired t-tests for within-group comparisons and independent t-tests for exploratory between-group analyses.

Results: In total, 39 participants were enrolled (61% acceptance rate), with 19 randomized to COPD Wellness alone and 20 to COPD Wellness with HA. Median session attendance was higher in the HA group (6 vs 4 sessions), with greater adherence (53% vs 37%). CAT scores improved significantly overall (mean improvement 3.2, P = .01), with greater improvements among participants in the HA group (5.6-point reduction, P = .01). No significant changes were observed in the 6MWD, D-12 score, PHQ-8, or exacerbation rates. No adverse events were reported.

Conclusions: The COPD Wellness program demonstrated feasibility, safety, and acceptability within a safety-net health care setting. The integration of HA addressed key social barriers, improving adherence and leading to greater improvements in COPD symptom burden compared with the COPD Wellness program alone. Future studies should explore scaling this model and assessing its long-term benefits in resource-limited environments.

Background: The exhaled breath of infected, mechanically ventilated patients poses an infection risk to health care workers. Proper expiratory gas filtration with heat and moisture exchanger filters (HMEF) or filters could reduce that phenomenon. Current laboratory means of assessing the filtration efficiency are limited to the use of monodisperse aerosols at a single humidity level and flow. This study aims to examine the filtration efficiency of various devices under simulated clinical conditions, namely against a broad range of particle sizes containing viruses at different levels of gas humidity and flow.

Methods: A wind tunnel was adapted to evaluate the filtration efficiency of 4 devices (HME, HMEF, filters, and HEPA-HMEF) against viral aerosols. Bacteriophages PhiX174 and MS2 were used as a proxy for human viruses.

Results: In general, particulate filtration was significantly increased under dry versus humid conditions and with low versus high flows (P < .05). The HEPA filter significantly outperformed all other devices under all tested conditions in filtration efficiency. Both HMEF and filter showed approximately a 1% decrease in absolute differences compared with the reference method (∼99% vs 99.99%). This difference could represent an emission of as many as 10² SARS-CoV-2 copies per hour by an ICU patient, which is enough to spread the infection.

Conclusions: Accurate testing of filtration function has long gone unexamined, and in preparation for the next respiratory pandemic, better evaluation of devices that filter potentially dangerous pathogens is vital for health care professionals and systems. Standard filtration testing should be adapted to mimic the clinical usage of HMEs and filters.

Background: The interaction between nebulizer technology and mechanical ventilation can be confusing. Mesh technology has recently been quantified using the mass balance, a technique that measures all aerosol delivered and lost in ventilator circuits. Data for jet nebulizers are limited, and ventilator technology has changed over time. The present study was designed to better define aerosol behavior during jet nebulization by testing device position, gas source, humidification, inspiratory time (T_I), and circuit compliance.

Methods: Using radiolabeled particles, mass balance and output rate were measured for the AeroTech nebulizer placed close to the ventilator (IP), Y-piece (YP), and proximal to ETT (DY) in aerosol HME or humidified settings. The nebulizer was driven continuously (8 L/m, 50 PSIG) or by breath actuation (BA) during volume control ventilation at two inspiratory times (T_I 0.7 and 0.55 s). Five ventilators and two circuits with different tubing compliance were tested. Radiolabeled saline (3 mL, Tc^99m) was nebulized. A well counter measured filters inhaled and expiratory mass (IM, EM), and nebulizer residual (NR). Tubing deposition was measured with a gamma camera. A shielded ratemeter measured output rate and treatment time.

Results: Mass balance ranged from 96 to 104% (no. = 66). IM obtained with IP, HME circuit, continuous nebulization (29.8 ± 5%), IP, and BA (26.8 ± 4%); with humidification, continuous (15 ± 1%), BA (27.1 ± 4). Lowest IM at YP position, HME (8.8 ± .6%). Circuit losses ≤20%. EM was lowest for IP (19.2 ± 2%) and highest for YP and DY (46 ± 3%). NR was higher with BA (43.1 ± 6 vs 37.1 ± 3, P = .002). Higher tubing compliance lowered IM (21.8 ± .7% vs 28.3 ± 3% [no. = 9], P = .01). Treatment time for IP, continuous, HME circuit (10 min), and BA circuit (50 min). Changing T_I (0.55 s) reduced IM and further increased treatment time.

Conclusions: Optimal conditions for jet nebulization were IP position, HME circuit, continuous nebulization, and stiff tubing. Humidification should be supplied with an aerosol HME. If active humidification, IP breath-actuated was most efficient but with marked increase in treatment time.