Determinantes da pneumonia associada à ventilação invasiva numa unidade de cuidados intensivos de um hospital central / Determinants of invasive ventilator-associated pneumonia in an intensive care unit of a central hospital / Determinantes de la neumonía asociada a la ventilación invasiva en una unidad de cuidados intensivos de un hospital central

Resumo Enquadramento: As infeções associadas aos cuidados de saúde (IACS) são uma problemática atual dos sistemas de saúde variando a sua incidência, prevalência do contexto de cuidados. A pneumonia associada à ventilação (PAV) é disso um exemplo ocorrendo em unidades de cuidados intensivos (UCI). Objetivo: Analisar determinantes da PAV, em doentes internados numa UCI de um hospital central do norte de Portugal. Metodologia: Estudo descritivo-correlacional e retrospetivo, com base nos registos de 705 doentes internados na UCI. Resultados: Constituíram-se determinantes da PAV o sexo masculino, tratamento prévio com antibiótico, reintubação endotraqueal, nível de consciência, pressão de cuff, tempo de ventilação, diagnóstico de entrada lesões, envenenamento e algumas outras consequências de causas externas. A incidência de PAV foi de 4,5%. Conclusão: O uso criterioso de antibióticos, o menor tempo possível de ventilação invasiva, a implementação de protocolos de desmame ventilatório e auditorias ao cumprimento da bundle da PAV podem contribuir para melhores cuidados e intervenções de enfermagem mais eficazes e seguras.

Abstract Background: Healthcare-associated infections are a prevalent issue in health systems that affect everyone. The incidence and prevalence of healthcare-associated infections depend on the context in which they occur. An example of this is ventilator-associated pneumonia in intensive care units. Objective: To analyze the determinants of ventilator-associated pneumonia in an intensive care unit of a central hospital in northern Portugal. Methodology: A retrospective, descriptive-correlational quantitative study was conducted with 705 patients admitted to the ICU of the hospital under investigation. Results: The results show that male gender, previous antibiotic use, endotracheal reintubation, level of consciousness, cuff pressure, ventilation time, injury, poisoning, and certain other consequences of external causes as admitting diagnosis are among the determinants of ventilator-associated pneumonia. Moreover, the incidence of ventilator-associated pneumonia was of 4.5%. Conclusion: The study recommends the judicious use of antibiotics, limiting the duration of invasive ventilation, implementing ventilator weaning protocols, and auditing compliance with the care bundle for ventilator-associated pneumonia. This study sheds light on the prevention of ventilator-associated pneumonia and its recommendations contribute to better care and more effective and safer nursing interventions.

Resumen Marco contextual: Las infecciones asociadas a los cuidados sanitarios (IACS) son un problema actual en los sistemas sanitarios, y su incidencia y prevalencia varían en función del entorno asistencial. Un ejemplo de ello es la neumonía asociada a la ventilación mecánica (PAV), que se da en las unidades de cuidados intensivos (UCI). Objetivo: Analizar los determinantes de la PAV en pacientes ingresados en la UCI de un hospital central del norte de Portugal. Metodología: Estudio descriptivo-correlacional y retrospectivo, basado en los registros de 705 pacientes ingresados en la UCI. Resultados: Los factores determinantes de la PAV fueron el sexo masculino, el tratamiento antibiótico previo, la reintubación endotraqueal, el nivel de consciencia, la presión del manguito, el tiempo de ventilación, el diagnóstico de entrada de lesiones, la intoxicación y algunas otras consecuencias de causas externas. La incidencia de PAV fue del 4,5%. Conclusión: El uso prudente de antibióticos, el menor tiempo posible de ventilación invasiva, la aplicación de protocolos de destete del ventilador y las auditorías de cumplimiento del paquete de PAV pueden contribuir a mejorar los cuidados y a que las intervenciones de enfermería sean más eficaces y seguras.

Efficacy of noninvasive ventilator treatment in patients with severe chronic obstructive pulmonary disease (COPD) type II respiratory failure.

OBJECTIVE: To investigate the efficacy of noninvasive ventilator usage for type II respiratory failure in patients with severe chronic obstructive pulmonary disease (COPD). METHODS: A total of 124 patients with COPD complicated with type II respiratory failure were divided into an observation group (n = 63) and a control group (n = 61) according to their intervention protocols. The patients in the observation group received noninvasive ventilator intervention, and the patients in the control group received bronchodilators, cough suppressants, oxygen therapy, anti-infection medications, nutritional support, and correction of electrolyte imbalances. Lung function indexes, arterial blood gas index, and inflammatory indicators were collected to assess the efficacy of noninvasive ventilator treatment in patients with severe COPD and type II respiratory failure. RESULTS: The levels of FEV1, FEV1/FVC and FEV1% of the two groups after treatment were significantly higher than those before treatment (P<0.05), with significantly higher levels in the observation group than the control group (all P<0.05). Post-treatment levels of PaCO2 decreased significantly while the post-treatment levels of PaO2 increased significantly (all P<0.05). Additionally, the levels of WBC, CRP and PCT of the control group was significantly higher than that of the observation group after treatment (all P<0.05). CONCLUSION: Noninvasive ventilator treatment can improve hypoxemia, improve lung function and reduce inflammatory responses in patients with COPD complicated with type II respiratory failure, suggesting its potential for wider clinical application.

Tissue-Compatible and Lubricated Hydrogel Catheter with Promising Activity Against Polymicrobial Infections for Ventilator-Associated Pneumonia Prevention.

Endotracheal intubation is a vital means of saving critically ill patients. However, the inserted catheter often causes tissue damage and the formation of tenacious biofilms containing drug-resistant bacteria and fungi, leading to severe ventilator-associated pneumonia (VAP). Currently, the resolution of VAP is usually based on antibiotic treatment and lacks targeted prophylaxis. Here, a quaternary phosphonium salts functionalized hydrogel catheter that enhances tissue compatibility yet inhibits complex and tenacious pathogens in the catheter, thus preventing VAP is reported. By copolymerizing the quaternary phosphonium electrolyte and acrylic acid monomers, the hydrogel catheter demonstrates good shape-supporting ability, and its strength and modulus can be adjusted over a wide range to meet the needs of different ages. Moreover, it possesses good tissue compatibility, antifouling properties, stable lubrication capability, and superior hydrophilicity, which may mitigate tissue damage caused by contact. Importantly, the hydrogel catheter demonstrates potent broad-spectrum intrinsic antimicrobial activity, eradicating nearly 99% of multi-drug resistant bacteria and 80% of fungi. To validate its role in preventing VAP, the real VAP pathogenesis process is mimicked, establishing a polymicrobial infections model considering time effects. The results prove that the hydrogel catheter effectively inhibits the invasion of various drug-resistant pathogens and prevents biofilm formation.

Nebulized Dexmedetomidine Alleviates Oxidative Stress in Ventilator-induced Lung Injury via Keap1-Nrf2-ARE Pathway.

This study aimed to explore the underlying mechanism of nebulized dexmedetomidine (DEX) in ameliorating ventilator-induced lung injury (VILI)-induced oxidative stress in rats. Forty 7 to 8-week-old Sprague-Dawley rats at the specific pathogen-free level were randomized into the control group, model group, nebulized dexmedetomidine (WH-YM) group, and dexmedetomidine intravenous infusion (JM-YM) group, each containing 10 rats. Except for the control group, rats in the other groups underwent mechanical ventilation (tidal volume,  40 mL/kg; respiratory rate, 70 breaths per minute; inspiratory-to-expiratory ratio, 1:2; fraction of inspired oxygen, 21%; positive end-expiratory pressure, 0 cmH2O). Nebulized DEX (6.3 µg/kg), and isodose intravenous DEX  were given to rats of WH-YM and JM-YM groups prior to ventilation. Post 4-hour ventilation, rats were euthanized. Lung tissue wet-to-dry weight ratio, H&E staining for assessing diffuse alveolar damage (DAD), and expression levels of Nrf2 and Keap1 detected by qRT-PCR and Western blot were compared. Inflammatory markers TNF-α, IL-2, and IL-6, and oxidative stress indices malondialdehyde (MDA) and superoxide dismutase (SOD), were quantified in lung tissues and serum samples using commercial kits.  Rats in the WH-YM and JM-YM groups demonstrated significant ameliorations in the wet-to-dry weight ratio and DAD score, decreased Keap1, TNF-α, IL-2, and IL-6 levels in lung tissues and serum samples, but increased Nrf2 and SOD level than those of controls. These changes were more pronounced in the WH-YM group than in the JM-YM group. DEX effectively alleviates VILI-induced oxidative stress and inflammation via the Keap1-Nrf2-ARE signaling pathway., especially in the nebulized administration.

Polymyxin B Peptide Hydrogel Coating: A Novel Approach to Prevent Ventilator-Associated Pneumonia.

Ventilator-associated pneumonia (VAP) remains one of the most common hospital-acquired infections (HAI). Considering the complicated diagnosis and the lack of effective treatment, prophylactic measures are suggested as the new standard to prevent the disease. Although VAP often manifests a polymicrobial nature, Pseudomonas aeruginosa remains one of the pathogens associated with the highest morbidity and mortality rates within these mechanically ventilated patients. In this paper, we report on the development of an antibacterial hydrogel coating using the polymyxin B (PMB) peptide to prevent bacterial adhesion to the polymeric substrate. We fully characterized the properties of the coating using atomic force microscopy (AFM), scanning electron microscopy (SEM), wettability analyses and Fourier-transform infrared (FTIR) and Raman spectroscopy. Furthermore, several biological assays confirmed the antibacterial and anti-biofilm effect of the tubing for at least 8 days against P. aeruginosa. On top of that, the produced coating is compliant with the requirements regarding cytocompatibility stated in the ISO (International Organization for Standardization) 10993 guidelines and an extended release of PMB over a period of at least 42 days was detected. In conclusion, this study serves as a foundation for peptide-releasing hydrogel formulas in the prevention of VAP.

Fiberoptic bronchoscopy for the prevention of ventilator-associated pneumonia: a meta-analysis of randomized controlled trials.

INTRODUCTION: Ventilator-associated pneumonia (VAP) causes increased time of mechanical ventilation (MV), prolonged intensive care unit (ICU) stay, and a higher mortality risk. The systematic review and meta-analysis aimed to compare the efficacies between fiberoptic bronchoscopy (FOB) and general sputum suction for the prevention of VAP in patients with invasive MV. METHODOLOGY: Relevant randomized controlled trials (RCTs) were obtained via a search of PubMed, Embase, Cochrane Library, Wanfang, and CNKI databases. A random-effects model was used to pool the results if significant heterogeneity was observed. Otherwise, a fixed-effects model was used. RESULTS: Sixteen RCTs were included. Compared to general sputum suction, sputum suction with FOB was associated with a significantly reduced risk of VAP (risk ratio [RR]: 0.56, 95% CI: 0.47 to 0.67, p < 0.001; I2 = 0%). Subgroup analyses showed that the combination of FOB-assisted sputum suction with bronchoalveolar lavage (BAL) further reduced the risk of VAP as compared to FOB-assisted sputum suction alone (p for subgroup difference = 0.04). In addition, FOB-assisted treatment was also associated with a reduced MV time (mean difference [MD]: -2.19 days, 95% CI: -2.69 to -1.68, p < 0.001; I2 = 18%), a shorter ICU stay (MD: 2.9 days, 95% CI: -3.68 to -2.13, p < 0.001; I2 = 34%), and a reduced mortality risk (RR: 0.46, 95% CI: 0.24 to 0.90, p = 0.02; I2 = 0%) in patients with invasive MV. CONCLUSIONS: FOB for sputum suction and BAL in patients with invasive MV is effective in reducing the incidence of VAP.

Features Associated With the Presence of Specific Bacterial Strains in Pediatric Tracheostomy.

BACKGROUND: Tracheostomy bypasses physical barriers that decrease microbial access to the lower airway, which can lead to changes to the lung microbiota. Patients often become chronically colonized with potential pathogens. This study described the incidence and prevalence of specific organisms in a 5-y cohort of children with tracheostomy. METHODS: This retrospective cohort of children aged 0-18 y with tracheostomy identified associations between microbial species and subject characteristics including reason for tracheostomy, gastrostomy tube (G-tube), fundoplication, and ventilator use using chi-square test or Fisher exact test. RESULTS: Of 113 eligible patients, 79 (57% male) met study inclusion criteria. Reasons for tracheostomy included airway obstruction secondary to craniofacial anomalies in 16 children (20%), upper-airway obstruction in 14 subjects (17.3%), neuromuscular disorder in 19 subjects (24%), bronchopulmonary dysplasia with or without pulmonary hypertension in 17 subjects (21%), and congenital heart disease in 13 subjects (16%). Most (69%) used a ventilator for at least 6 h/d; 63% had a G-tube; 41% also had a Nissen fundoplication. Of the 20% with upper-airway obstruction, one third were ventilator dependent, unlike other diagnoses where 57% used a ventilator. Staphylococcus aureus (52/113), Pseudomonas aeruginosa (43/113), and Stenotrophomonas species (39/113) were the most frequently identified bacterial species. Most microbes identified were not associated with subjects underlying diagnoses, ventilator use, or feeding type. However, there was a significant association between upper-airway obstruction and group B Streptococcus species and G-tube with P. aeruginosa. CONCLUSIONS: This retrospective single-site descriptive cohort analysis of pediatric subjects with long-term tracheostomy identified trends in microbial prevalence. The presence of specific bacterial strains was more likely to follow individual subject trajectories than sequential appearance of species. P. aeruginosa was associated with G-tube and Streptococcus species with upper-airway obstruction. Ventilator dependence was not associated with specific microbial profiles.

Influence of compliance and resistance of the test lung on the accuracy of the tidal volume delivered by the ventilator.

BACKGROUND: Large variations in respiratory system compliance and resistance may cause the accuracy of tidal volume (VT) delivery beyond the declared range. This study aimed at evaluating the accuracy of VT delivery using a test lung model to simulate pulmonary mechanics under normal or disease conditions. METHODS: In vitro assessment of the VT delivery accuracy was carried out on two commercial ventilators. Measurements of the inspired and expired VT from the ventilator and FlowAnalyser were compared to evaluate the separated and combined influences of compliance and resistance on the delivered VT accuracy. To do this, the errors of five delivered volumes (30 ml, 50 ml, 100 ml, 300 ml, and 500 ml) were checked under 29 test conditions involving a total of 27 combinations of resistance and compliance. RESULTS: For the tested ventilator S1 with a flow sensor near the expiratory valve, the average of expired VT errors (ΔVTexp) in three measurements (4 test conditions for each measurement) correlated to test lung compliance (r=-0.96, p = 0.044), and the average of inspired VT errors (ΔVTins) correlated to compliance (r = 0.89, p = 0.106); for the tested ventilator S2 with a flow sensor located at the Y piece, no clear relationship between compliance and ΔVTexp or ΔVTins was found. Furthermore, on two ventilators tested, the current measurements revealed a poor correlation between test lung resistance and ΔVTins or ΔVTexp, and the maximum values of ΔVTexp and ΔVTins correspond to the maximum resistance of 200 cmH2O/(L/s), at which the phenomenon of the flap fluttering in the variable orifice flow senor was observed, and the recorded peak inspiratory pressure (Ppeak) was much higher than the Ppeak estimated by the classical equation of motion. In contrast, at the lower resistance values of 5, 20, 50 and 100 cmH2O/(L/s), the recorded Ppeak was very close to the estimated Ppeak. Overall, the delivered VT errors were in the range of ± 14% on two ventilators studied. CONCLUSIONS: Depending on the placement site of the flow sensor in the ventilator circuit, the compliance and resistance of the test lung have different influences on the accuracy of VT delivery, which is further attributed to different fluid dynamics effects of the compliance and resistance. The main influence of compliance is to raise the peak inspiratory pressure Ppeak, thereby increasing the compression volume within the ventilator circuit; whereas a high resistance not only contributes to elevating Ppeak, but more importantly, it governs the gas flow conditions. Ppeak is a critical predictive indicator for the accuracy of the VT delivered by a ventilator.

Impact of sleep disturbances on outcomes in intensive care units.

BACKGROUND: Sleep deprivation is common in intensive care units (ICUs) and may alter respiratory performance. Few studies have assessed the role of sleep disturbances on outcomes in critically ill patients. OBJECTIVES: We hypothesized that sleep disturbances may be associated with poor outcomes in ICUs. METHODS: Post-hoc analysis pooling three observational studies assessing sleep by complete polysomnography in 131 conscious and non-sedated patients included at different times of their ICU stay. Sleep was assessed early in a group of patients admitted for acute respiratory failure while breathing spontaneously (n = 34), or under mechanical ventilation in patients with weaning difficulties (n = 45), or immediately after extubation (n = 52). Patients admitted for acute respiratory failure who required intubation, those under mechanical ventilation who had prolonged weaning, and those who required reintubation after extubation were considered as having poor clinical outcomes. Durations of deep sleep, rapid eye movement (REM) sleep, and atypical sleep were compared according to the timing of polysomnography and the clinical outcomes. RESULTS: Whereas deep sleep remained preserved in patients admitted for acute respiratory failure, it was markedly reduced under mechanical ventilation and after extubation (p < 0.01). Atypical sleep was significantly more frequent in patients under mechanical ventilation than in those breathing spontaneously (p < 0.01). REM sleep was uncommon at any time of their ICU stay. Patients with complete disappearance of REM sleep (50% of patients) were more likely to have poor clinical outcomes than those with persistent REM sleep (24% vs. 9%, p = 0.03). CONCLUSION: Complete disappearance of REM sleep was significantly associated with poor clinical outcomes in critically ill patients.

Evaluation of ventilator-associated pneumonia care practice in the intensive care units of a comprehensive specialized hospital in Northwest Ethiopia: a 1.5-year prospective observational study.

BACKGROUND: Nosocomial infections pose a global health threat, with Ventilator-Associated Pneumonia (VAP) emerging as a prominent hospital-acquired infection, particularly in intensive care units (ICU).VAP is the commonest form of pneumonia in ICUs, contributing significantly to morbidity and mortality rates, which can reach around 30%. Despite the substantial impact of VAP on healthcare, there is a lack of data on adherence to VAP prevention protocols in our hospital. Consequently, this study aims to assess the adherence to ventilator-associated pneumonia care bundles in critical care units at a comprehensive specialized hospital in northwest Ethiopia. METHODS: A hospital-based prospective observational study was conducted from July 3, 2022, to January 7, 2024. All adult patients who were on mechanical ventilators for more than 48 h during the study period were included. Data were collected using the Institute of Healthcare Improvement VAP prevention standards as checklists via direct observation and chart review. The data were entered and analyzed using SPSS version 20. RESULTS: A total of 300 surgical and medical ICU patients were observed. Among the patients, 66.3% were from the medical ICU. In terms of admission reasons, 22.3%, 15.7% and, 12% were attributed to infections excluding respiratory origin, respiratory disorders, and other causes, respectively. The rate of compliance with all components of the bundle was 70%. A 100% adherence rate was observed for the prophylaxis for peptic ulcer and deep vein thrombosis (DVT). The lowest adherence rate was observed in the practice of oral hygiene with 0.5% chlorhexidine solution (0%) followed by humidification with heat and moisture exchangers (23.3%). Endotracheal tube cuff pressure measurement and use of endotracheal tubes with subglottic suction were not applicable. CONCLUSION: The study revealed suboptimal compliance with the VAP care bundle, indicating unsatisfactory overall practice. Specific attention is warranted for subglottic suction, cuff pressure measurement, humidification, oral care with chlorhexidine, and sedation vacation.

Atelectrauma can be avoided if expiration is sufficiently brief: evidence from inverse modeling and oscillometry during airway pressure release ventilation.

BACKGROUND: Airway pressure release ventilation (APRV) has been shown to be protective against atelectrauma if expirations are brief. We hypothesize that this is protective because epithelial surfaces are not given enough time to come together and adhere during expiration, thereby avoiding their highly damaging forced separation during inspiration. METHODS: We investigated this hypothesis in a porcine model of ARDS induced by Tween lavage. Animals were ventilated with APRV in 4 groups based on whether inspiratory pressure was 28 or 40 cmH2O, and whether expiration was terminated when end-expiratory flow reached either 75% (a shorter expiration) or 25% (a longer expiration) of its initial peak value. A mathematical model of respiratory system mechanics that included a volume-dependent elastance term characterized by the parameter E 2 was fit to airway pressure-flow data obtained each hour for 6 h post-Tween injury during both expiration and inspiration. We also measured respiratory system impedance between 5 and 19 Hz continuously through inspiration at the same time points from which we derived a time-course for respiratory system resistance ( R rs ). RESULTS: E 2 during both expiration and inspiration was significantly different between the two longer expiration versus the two shorter expiration groups (ANOVA, p < 0.001). We found that E 2 was most depressed during inspiration in the higher-pressure group receiving the longer expiration, suggesting that E 2 reflects a balance between strain stiffening of the lung parenchyma and ongoing recruitment as lung volume increases. We also found in this group that R rs increased progressively during the first 0.5 s of inspiration and then began to decrease again as inspiration continued, which we interpret as corresponding to the point when continuing derecruitment was reversed by progressive lung inflation. CONCLUSIONS: These findings support the hypothesis that sufficiently short expiratory durations protect against atelectrauma because they do not give derecruitment enough time to manifest. This suggests a means for the personalized adjustment of mechanical ventilation.

Korean Guidelines for the Management and Antibiotic Therapy in Adult Patients with Hospital-Acquired Pneumonia.

BACKGROUND: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are correlated with high morbidity and mortality rates. Guidelines that consider local epidemiologic data are fundamental for identifying optimal treatment strategies. However, Korea has no HAP/VAP guidelines. METHODS: This study was conducted by a committee of nine experts from the Korean Academy of Tuberculosis and Respiratory Diseases Respiratory Infection Study Group using the results of Korean HAP/VAP epidemiologic studies. Eleven key questions for HAP/VAP diagnosis and treatment were addressed. The Convergence of Opinion on Suggestions and Evidence (CORE) process was used to derive suggestions, and evidence levels and recommendation grades were in accordance with the Grading of Recommendations Assessment Development and Evaluation (GRADE) methodology. RESULTS: Suggestions were made for the 11 key questions pertinent to diagnosis, biomarkers, antibiotics, and treatment strategies for adult patients with HAP/VAP. CONCLUSION: Using the CORE process and GRADE methodology, the committee generated a series of recommendations for HAP/VAP diagnosis and treatment in the Korean context.

Predictive Value of Diaphragm Muscle Ultrasound for Ventilator Weaning Outcomes After Cervical Spinal Cord Injury: A Retrospective Case Series.

OBJECTIVES: Neuromuscular respiratory failure after cervical spinal cord injury (cSCI) can lead to dependence on an invasive mechanical ventilator. Ventilator-free breathing after cSCI is associated with improved morbidity, mortality, and quality of life. We investigated the use of diaphragm muscle ultrasound to predict ventilator weaning outcomes after cSCI. METHODS: This is a retrospective case series conducted at a university-affiliated freestanding inpatient rehabilitation facility. We identified patients with cSCI who had a tracheostomy and were dependent on an invasive mechanical ventilator at the time of admission to inpatient rehabilitation. A diaphragm muscle ultrasound was performed, which included measurements of the thickness of the diaphragm and a calculation of the thickening ratio (TR), which reflects diaphragm muscle contraction. The primary outcome measure was the need for mechanical ventilation at time of discharge from the inpatient rehabilitation facility. Successful ventilator weaning was defined as either daytime or full 24-hour ventilator-free breathing. RESULTS: Of the 21 patients enrolled, 11 (52%) were able to wean successfully (partially or fully) from the ventilator. Of the ultrasound measurements that were taken, the TR was the optimal predictor for ventilator weaning outcomes. A threshold of TR ≥ 1.2 as the maximum hemidiaphragm measurement had a sensitivity of 1.0 and specificity of 0.90 for predicting ventilator weaning. CONCLUSION: Normal diaphragm contractility (TR ≥ 1.2) as determined by diaphragm muscle ultrasound is a strong positive predictor for successful ventilator weaning in patients with cSCI. Utilizing diaphragm ultrasound, rehabilitation physicians can set precision rehabilitation goals regarding ventilator weaning for inpatients with respiratory failure after cSCI, potentially improving both outcomes and quality of life.

Induction of subject-ventilator asynchrony by variation of respiratory parameters in a lung injury model in pigs.

BACKGROUND: Subject-ventilator asynchrony (SVA) was shown to be associated with negative clinical outcomes. To elucidate pathophysiology pathways and effects of SVA on lung tissue histology a reproducible animal model of artificially induced asynchrony was developed and evaluated. METHODS: Alterations in ventilator parameters were used to induce the three main types of asynchrony: ineffective efforts (IE), auto-triggering (AT), and double-triggering (DT). Airway flow and pressure, as well as oesophageal pressure waveforms, were recorded, asynchrony cycles were manually classified and the asynchrony index (AIX) was calculated. Bench tests were conducted on an active lung simulator with ventilator settings altered cycle by cycle. The developed algorithm was evaluated in three pilot experiments and a study in pigs ventilated for twelve hours with AIX = 25%. RESULTS: IE and AT were induced reliably and fail-safe by end-expiratory hold and adjustment of respiratory rate, respectively. DT was provoked using airway pressure ramp prolongation, however not controlled specifically in the pilots. In the subsequent study, an AIX = 28.8% [24.0%-34.4%] was induced and maintained over twelve hours. CONCLUSIONS: The method allows to reproducibly induce and maintain three clinically relevant types of SVA observed in ventilated patients and may thus serve as a useful tool for future investigations on cellular and inflammatory effects of asynchrony.

Risk factors and outcomes of ventilator-associated pneumonia in patients with traumatic brain injury: A systematic review and meta-analysis.

BACKGROUND: Ventilator-associated pneumonia (VAP) is a common complication in traumatic brain injury (TBI) patients, which increases morbidity and negatively affects outcomes. Risk factors and outcomes in these patients remain controversial. The aim of the present study is to explore the risk factors and clinical outcomes of patients with VAP and TBI. METHODS: Two researchers conducted independent systematic literature searches of Pubmed, Cochrane Database, Scopus, Medline Ovid, Science Direct databases, published from inception to January 2024. The Newcastle-Ottawa scale was used to assess study quality. A meta-analysis was performed using a random-effects model when heterogeneity I2 > 50 % and a fixed-effects model when I2 < 50 %; in addition, a subgroup analysis was performed to explore VAP risk factors, and publication bias was assessed with the funnel plot and Begg's and Egger's tests. All results were considered statistically significant when p < 0.05. The certainty of the evidence was evaluated using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology. RESULTS: Twelve studies were included in the meta-analysis with a total of 2883 patients. Male gender [OR 1.58 (95 % CI 1.23, 2.02) p < 0.05 I2 0 %] and abbreviated injury scale (head: H-AIS) [≥ 3 OR 2.79 (95 % CI 1.58, 4.93) p < 0.05 I2 0 %] increased the risk of VAP. After subgroup analysis, blood transfusion on admission [OR 1.97 (95 % CI 1.16-3.35) p ≤0.05 I2 5 %] and barbiturate infusion [OR 3.55 (95 % CI 2.01-6.30) p ≤0.05 I2 0 %] became risk factors. Prophylactic antibiotic use [OR 0.67 (95 % CI 0.51-0.88) p ≤0.05 I2 0 %] and younger age MD -3.29 (95 % CI -5.18, -1.40) p ≤0.05 I2 41 %] emerged as significant protective factors. In VAP patients ICU stay [MD 7.02 (95 % CI 6.05-7.99) p ≤0.05 I2 37 %], duration of mechanical ventilation [MD 5.79 (95 % CI 4.40, 7.18) p ≤0.05 I2 79 %] and hospital stay [MD 11.88 (95 % CI 8.71-15.05) p ≤0.05 I2 0 %] were significantly increased. The certainty of the evidence was moderate-high for the outcomes studied. CONCLUSIONS: Male gender, H-AIS ≥ 3, blood transfusion on admission, and barbiturate infusion were risk factors for VAP. In patients with VAP, ICU stay, duration of mechanical ventilation, hospital stay were significantly increased.

Ability of the SMART-COP score to predict the need for intensive care unit admission and mortality in older patients with non-ventilator-associated hospital-acquired pneumonia: A retrospective observational study.

AIM: To evaluate the ability of SMART-COP (systolic blood pressure, multilobar infiltrates, albumin, respiratory rate, tachycardia, confusion, oxygen and pH) score to predict the need for intensive care unit (ICU) admission and mortality among patients with non-ventilator-associated hospital-acquired pneumonia (NV-HAP) and to compare ICU-hospitalized patients with those followed-up in the clinic, as well as the patients who survived with those who died in the ICU, in terms of clinical and laboratory parameters. METHODS: A total of 203 patients (aged > 65 years) who were diagnosed with NV-HAP while staying in the geriatric clinic were enrolled in this retrospective observational study. Patient information was retrieved from hospital files. RESULTS: In a total of 203 patients with NV-HAP, the rate of ICU admission was 77.3% and the rate of mortality was 40.9%. The SMART-COP score was significantly higher in those admitted to the ICU and those died in the ICU (ICU nonsurvivors). The rate of ICU mortality was 52.9%. The SMART-COP score had significantly poor to moderate ability to predict the need for ICU admission (area under the curve [AUC] = 0.583) and both in-hospital mortality (AUC = 0.633) and ICU mortality (AUC = 0.617) with low sensitivity. The regression analysis revealed that a one-unit increase in SMART-COP score resulted in a 1.2-fold increase in both the hospital and ICU mortality (P < 0.05 for both) and 1.1-fold increase in ICU admission (P = 0.154). CONCLUSION: The SMART-COP score has poor to moderate ability to predict the need for ICU admission, in-hospital mortality and ICU mortality, and a one-unit increase in the SMART-COP score significantly increases the risk of both hospital and ICU mortality. Geriatr Gerontol Int 2024; ••: ••-••.

Predicting nosocomial pneumonia risk in level-1 trauma patients: An external validation study using the trauma quality improvement program.

BACKGROUND: Early identification of patients at risk of nosocomial pneumonia enables the opportunity for preventative measures, which may improve survival and reduce costs. Therefore, this study aimed to externally validate an existing prediction model (issued by Croce et al.) to predict nosocomial pneumonia in patients admitted to US level-1 trauma centers. METHODS: A retrospective cohort study including patients admitted to level-1 trauma centers and registered in the TQIP, a US nationwide trauma registry, admitted between 2013-2015 and 2017-2019. The main outcome was total nosocomial pneumonia for the first period and ventilator-associated pneumonia (VAP) for the second. Model discrimination and calibration were assessed before and after recalibration. RESULTS: The study comprised 902,231 trauma patients (N2013-2015 â€‹= â€‹180,601; N2017-2019 â€‹= â€‹721,630), with a median age of 52 in both periods, 64-65 â€‹% male, and approximately 90 â€‹% sustaining blunt traumatic injury. The median Injury Severity Scores were 13 (2013-2015) versus 9 (2017-2019); median Glasgow Coma Scale scores were 15. Nosocomial pneumonia incidence was 4.4 â€‹%, VAP incidence was 0.7 â€‹%. The original model demonstrated good to excellent discrimination for both periods (c-statistic2013-2015 0.84, 95%CI 0.83-0.84; c-statistic2017-2019 0.92, 95%CI 0.91-0.92). After recalibration, discriminatory capacity and calibration for the lower predicted probabilities improved. CONCLUSIONS: The Croce model can identify patients admitted to US level-1 trauma centers at risk of total nosocomial pneumonia and VAP. Implementing (modified) Croce models in route trauma clinical practice could guide judicious use of preventative measures and prescription of additional non-invasive preventative measures (e.g., increased monitoring, pulmonary physiotherapy) to decrease the occurrence of nosocomial pneumonia in at-risk patients.

Family-Led Coaching of Patients During Weaning From Sedation and Mechanical Ventilation in the ICU.

BACKGROUND: ICU patients are weaned from sedation and mechanical ventilation through spontaneous awakening trials (SATs) and spontaneous breathing trials (SBTs). Weaning can be distressing for patients and their families. Family-led coaching could reassure patients and reduce stress for families by engaging them in patient care. This study developed and piloted a family-led coaching tool to support patients undergoing SATs/SBTs. METHODS: Patient and family member dyads were recruited from 2 medical-surgical ICUs in Calgary, Canada (February 3-August 1, 2023). Surveys were administered to collect family (1) demographics, (2) anxiety and satisfaction with ICU care, (3) feedback on the tool, and (4) attitudes about family presence during SATs/SBTs (also collected from clinicians). Tool feasibility was determined by calculating the proportions of (1) eligible patients who were recommended for participation in the study by clinicians and (2) families approached who consented to participate in the study. RESULTS: One thousand one hundred fifty patients were admitted to the study ICUs during the study period of which 819 received mechanical ventilation, and 42 were recommended by bedside clinicians for participation in the study. Twenty-five dyads were approached, 21 dyads consented to participate, and one withdrew consent before data collection. Of the enrolled families, 12 (60%) reported the coaching tool to be useful, and 5 (25%) recommended minor suggestions such as "shortening" the tool. Fourteen (70%) families reported positive experiences (through open-ended feedback) with being present for the SAT/SBT. State-Trait Anxiety Inventory (Y1) scores (scale range 20-80 points) significantly decreased in families from the first (pre coaching) to the second (post coaching) measures (mean decrease 8.2 points, SD 10.3, P = .001). All clinicians indicated they were comfortable with family presence and/or coaching during SATs/SBTs. CONCLUSION: Family-led coaching of patients during SATs/SBTs appears to be feasible, favorably perceived by families and clinicians, and potentially associated with lower family anxiety.

School adjustment experiences of ventilator-dependent children: A phenomenological study of mothers' perspectives.

PURPOSE: This study aimed to describe the experiences of ventilator-dependent children (VDC) in adjusting to school life from the perspectives of their mothers. DESIGN AND METHOD: This study employed a descriptive phenomenological approach. From July 2021 to September 2022, ten mothers of VDC were recruited via purposive sampling and underwent in-depth individual interviews. Data were analyzed using Colaizzi's phenomenological method. This study adheres to the COREQ guidelines for qualitative study. FINDINGS: Four themes emerged: (1) the transition and burden of the mother's role; (2) positive adjustment and assessment of resources; (3) develop strategies to meet health and learning needs; (4) expectations for accessible school environments. CONCLUSIONS: The mothers extensively assessed and adjusted their coping strategies on a rolling basis to ensure that their children received the resources that met their individual needs, promoted peer interactions, and helped adjustment to school life. The children's improvement and progress surpassed their mothers' expectations and demonstrated the benefits of a school education. Future educational settings should focus on building accessible school environments for special needs children. PRACTICE IMPLICATIONS: These findings allow healthcare professionals to assess the needs of VDC at different educational levels and create care plans that meet their healthcare and educational needs. This study also provides a reference for amending policies and regulations on individualized educational programs for VDC and developing guidelines for realizing accessible school environments to help them adjust to school life.