Background: Mechanical ventilators are essential life-support devices, yet evidence regarding device-related vulnerabilities remains limited compared with the extensive literature on human-factor–related adverse events. This study applied text-mining techniques to a large post-market surveillance database to examine ventilator malfunction reporting patterns and the effect of stratifying reports by device category. Methods: Adverse event reports related to mechanical ventilators submitted to the U.S. Food and Drug Administration’s Manufacturer and User Facility Device Experience database between January 2010 and December 2025 were stratified into life-supporting and noninvasive devices and analyzed using KH Coder. A random sample of the life-supporting reports was drawn for the primary analysis. Frequency analysis, co-occurrence network analysis, hierarchical cluster analysis, and correspondence analysis were performed. Device brand and year were used as external variables in the correspondence analysis. Results: A total of 193,926 reports met the eligibility criteria, of which 177,641 were classified as malfunctions. The analyses were restricted to reports classified as malfunctions. Among life-supporting ventilators, the reported malfunctions spanned several broad themes, including power and battery failures, circuit-board and electronic faults, breathing-circuit and gas-delivery problems, and issues involving monitoring and control functions. Among noninvasive devices, reports were concentrated in terms associated with a single foam-related recall, as well as connector corrosion and patient-reported symptoms. Nearly 1 in 5 malfunction reports did not document a confirmed device failure during patient use. Conclusions: Text mining of ventilator-related adverse event reports revealed distinct reporting patterns across life-supporting and noninvasive devices. These findings are exploratory and do not establish the frequency or causes of device failure. Stratification of reports by device category helped prevent the reporting patterns of individual devices from being obscured by a single recall. This study demonstrates the potential value of combining post-market surveillance data with text-mining methods to support medical device safety surveillance.
Pulmonary rehabilitation (PR) is a cornerstone of therapy for people with chronic lung disease. Over the years, there has been a tremendous amount of research in the field. Researchers have studied improved delivery methods for PR that improve patient outcomes. This article will review several important articles in the field over the last year.
Background: Negative-pressure ventilation (NPV) avoids a positive-pressure facial interface, but contemporary multi-center pediatric data comparing NPV with noninvasive positive-pressure ventilation (NIV) are limited. We describe modern NPV epidemiology and compare outcomes with NIV in children younger than 3 years with acute respiratory failure. Methods: We conducted a multi-center retrospective cohort study using the Virtual Pediatric Systems (VPS) database. Children younger than 3 years who received NPV or NIV during a pediatric ICU (PICU) admission for acute or acute-on-chronic respiratory failure were included; outpatient use of either modality was excluded. Subjects were categorized according to initial respiratory support modality. The primary outcome was endotracheal intubation after initiation of noninvasive respiratory support. The primary analysis used multivariable mixed-effects logistic regression with center included as a random intercept. Propensity-score matching using Pediatric Risk of Mortality III score, age, sex, weight, diagnostic variables, and center was performed as a sensitivity analysis. Results: Crude intubation rates were higher in the NPV group than in the NIV group (27.3% vs 10.4%, P < .001). After adjustment for measured subject-level factors and center-level clustering, ventilation modality was not independently associated with intubation (NIV vs NPV adjusted OR 0.675, 95% CI 0.393–1.158, P = .154). In the propensity-score-matched cohort, intubation remained numerically higher in the NPV group but was not statistically significant (NPV vs NIV OR 1.64, 95% CI 0.92–2.93, P = .12). Conclusions: In this multi-center retrospective cohort, NPV was used in a small minority of children younger than 3 years with acute respiratory failure. After adjustment for measured confounders and center-level clustering, ventilation modality was not independently associated with intubation. Prospective studies are needed to define optimal patient selection and the role of NPV in pediatric acute respiratory failure.
Background: Excess adipose tissue compresses dorsal lung regions that PEEP may not fully reverse in the supine position. Prone positioning, in combination with PEEP, can unload the lung, but whether regional responses differ by obesity is unknown. Methods: We measured regional lung compliance using electrical impedance tomography in 14 mechanically ventilated subjects with COVID-19 ARDS (6 with BMI >= 35 kg/m(2) and 8 with BMI <30 kg/m(2)). Measurements were taken during decremental PEEP titration in supine and prone positions, following recruitment maneuvers. Regional compliance was derived from pixel-level impedance change within each region of interest, divided by driving pressure and predicted body weight. Bayesian multilevel gamma regression models with patient-level random effects estimated the 3-way interaction between position, BMI group, and lung region on regional compliance, adjusted for age. Results: The overall cohort had a median P-aO2/F-IO2 of 108 mm Hg and median respiratory system compliance of 29 mL/cm H2O in the supine position. At the PEEP that produced the highest total respiratory system compliance in each position, the increase in dorsal regional compliance with prone positioning was greater in subjects with BMI >= 35 kg/m(2) compared with subjects with BMI <30 kg/m(2) (difference-in-differences: 0.16 mL/cm H2O/kg, 95% credible interval: 0.01 to 0.37; posterior probability: 98.0%). Regional compliance in ventral and central lung regions did not credibly differ between BMI groups. The direction and magnitude of the change in dorsal lung compliance between BMI groups were consistent across PEEP levels. Conclusions: Prone positioning was associated with a greater increase in dorsal lung compliance in subjects with BMI >= 35 kg/m(2) compared with subjects with BMI <30 kg/m(2). Our findings suggest that the response of regional compliance to prone positioning in ARDS differs by body mass index, identifying obesity as a population in whom positional unloading may be more effective.
Background: Aerosol delivery via high-flow nasal cannula (HFNC) is widely used. Although an asymmetrical cannula may improve clearance of gases within the anatomical dead space, its impact on aerosol delivery compared with the standard symmetrical cannula remains unclear. This study compared drug delivery efficiency between the symmetrical and asymmetrical cannulas under standardized conditions. Methods: An in vitro adult airway model, comprising a manikin and a ventilator-driven dual-chamber lung model, simulated spontaneous breathing to evaluate aerosol delivery. Filter-captured albuterol from a vibrating mesh nebulizer was quantified by spectrophotometry (230 nm) to determine delivery efficiency (the percentage of an inhaled dose of 2.5-mg nominal dose) for the symmetrical and asymmetrical cannulas over HFNC flows of 10-60 L/min with 4 breathing patterns combining quiet (15 breaths/min) or distressed breathing frequency (30 breaths/min) with low (300 mL) or high (600 mL) tidal volume (V-T). Results: During quiet breathing with low V-T, the maximum efficiency of albuterol delivery was higher for the asymmetrical versus the symmetrical cannula (mean +/- SD, 6.8 +/- 1.7% vs 3.3 +/- 1.7% at HFNC flow 20 L/min, respectively, P = .002) but not different with high V-T (17.4 +/- 1.1% vs 17.6 +/- 1.1% at HFNC flow 10 L/min, P = .89). Conversely, during distressed breathing, the maximum delivery efficiency was higher for the symmetrical versus the asymmetrical cannula with both low V-T (8.1 +/- 1% vs 4.8 +/- 0.4% at HFNC flow 10 L/min, respectively, P = .008) and high V-T (24.2 +/- 1.4% vs 16.2 +/- 1.4% at HFNC flow 20 L/min, P < .001). Conclusions: The asymmetrical cannula improved aerosol delivery compared with the symmetrical cannula during quiet breathing with low V-T. During distressed breathing, however, the symmetrical cannula was more efficient, regardless of V-T. Thus, the asymmetrical and symmetrical cannulas may be selected for drug delivery via a vibrating mesh nebulizer with an HFNC in patients with quiet and distressed breathing, respectively.
