Framework for Research Gaps in Pediatric Ventilator Liberation.

BACKGROUND: The 2023 International Pediatric Ventilator Liberation Clinical Practice Guidelines provided evidence-based recommendations to guide pediatric critical care providers on how to perform daily aspects of ventilator liberation. However, because of the lack of high-quality pediatric studies, most recommendations were conditional based on very low to low certainty of evidence. RESEARCH QUESTION: What are the research gaps related to pediatric ventilator liberation that can be studied to strengthen the evidence for future updates of the guidelines? STUDY DESIGN AND METHODS: We conducted systematic reviews of the literature in eight predefined Population, Intervention, Comparator, Outcome (PICO) areas related to pediatric ventilator liberation to generate recommendations. Subgroups responsible for each PICO question subsequently identified major research gaps by synthesizing the literature. These gaps were presented at an international symposium at the Pediatric Acute Lung Injury and Sepsis Investigators meeting in spring 2022 for open discussion. Feedback was incorporated, and final evaluation of research gaps are summarized herein. Although randomized controlled trials (RCTs) represent the highest level of evidence, the panel sought to highlight areas where alternative study designs also may be appropriate, given challenges with conducting large multicenter RCTs in children. RESULTS: Significant research gaps were identified in six broad areas related to pediatric ventilator liberation. Several of these areas necessitate multicenter RCTs to provide definitive results, whereas other gaps can be addressed with multicenter observational studies or quality improvement initiatives. Furthermore, a need for some physiologic studies in several areas remains, particularly regarding newer diagnostic methods to improve identification of patients at high risk of extubation failure. INTERPRETATION: Although pediatric ventilator liberation guidelines have been created, the certainty of evidence remains low and multiple research gaps exist that should be filled through high-quality RCTs, multicenter observational studies, and quality improvement initiatives.

Hospital Outcomes in Patients Who Developed Acute Respiratory Distress Syndrome After Community-Acquired Pneumonia.

Purpose: To identify risk factors for and outcomes in acute respiratory distress syndrome (ARDS) in patients hospitalized with community-acquired pneumonia (CAP). Methods: This is a retrospective study using the Premier Healthcare Database between 2016 and 2020. Patients diagnosed with pneumonia, requiring mechanical ventilation (MV), antimicrobial therapy, and hospital admission ≥2 days were included. Multivariable regression models were used for outcomes including in-hospital mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, and days on MV. Results: 1924 (2.7%) of 72 107 patients with CAP developed ARDS. ARDS was associated with higher mortality (33.7% vs 18.9%; adjusted odds ratio 2.4; 95% confidence interval [CI] 2.16-2.66), longer hospital LOS (13 vs 9 days; adjusted incidence risk ratio (aIRR) 1.24; 95% CI 1.20-1.27), ICU LOS (9 vs 5 days; aIRR 1.51; 95% CI 1.46-1.56), more MV days (8 vs 5; aIRR 1.54; 95% CI 1.48-1.59), and increased hospitalization cost ($46 459 vs $29 441; aIRR 1.50; 95% CI 1.45-1.55). Conclusion: In CAP, ARDS was associated with worse in-patient outcomes in terms of mortality, LOS, and hospitalization cost. Future studies are needed to explore outcomes in patients with CAP with ARDS and explore risk factors for development of ARDS after CAP.

Novel Method for Sealing Tracheostomies Immediately after Decannulation-An Acute Clinical Feasibility Study.

Tracheostomy decannulation leaves an iatrogenic passage in the upper airways. Inadequate sealing leads to pulmonary dysfunction and reduced voice quality. This study aimed to investigate the feasibility and impact of intratracheal tracheostomy sealing on laryngeal airflow and voice quality immediately after decannulation (ClinicalTrials.gov: NCT06138093). Fifteen adult, tracheostomized, intensive care unit patients were included from our hospital. A temporary, silicone-based sealing disc was inserted in the tracheostomy wound immediately after decannulation. Spirometry with measurement of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and peak expiratory flow (PEF) were performed as measures of airway flow. Voice recordings were assessed using an equal appearing interval scale from 1 to 5. Median FVC, FEV1, PEF, and voice quality score with interquartile range (IQR) was 883 (510-1910) vs. 1260 (1005-1723) mL (p < 0.001), 790 (465-1255) vs. 870 (617-1297) mL (p < 0.001), 103 (55-211) vs. 107 (62-173) mL (p = 0.720), and 2 (1-2.5) vs. 4 (3-5) points (p < 0.001), respectively, with open tracheostomy vs. after sealing the tracheostomy with the intratracheal sealing disc. This feasibility study showed that tracheostomy sealing with the intratracheal disc was safe and led to immediate improvements in FVC, FEV1, and voice quality.

Factors related to lung function outcomes in critically ill COVID-19 patients in South Korea.

BACKGROUND: New variants of the virus responsible for the coronavirus disease 2019 (COVID-19) pandemic continue to emerge. However, little is known about the effect of these variants on clinical outcomes. This study evaluated the risk factors for poor pulmonary lung function test (PFT). METHODS: The study retrospectively analyzed 87 patients in a single hospital and followed up by performing PFTs at an outpatient clinic from January 2020 to December 2021. COVID-19 variants were categorized as either a non-delta variant (November 13, 2020-July 6, 2021) or the delta variant (July 7, 2021-January 29, 2022). RESULTS: The median age of the patients was 62 years, and 56 patients (64.4%) were male. Mechanical ventilation (MV) was provided for 52 patients, and 36 (41.4%) had restrictive lung defects. Forced vital capacity (FVC) and diffusion capacity of the lung for carbon monoxide (DLCO ) were lower in patients on MV. Male sex (odds ratio [OR], 0.228) and MV (OR, 4.663) were significant factors for decreased DLCO . The duration of MV was associated with decreased FVC and DLCO . However, the type of variant did not affect the decrease in FVC (P=0.750) and DLCO (P=0.639). CONCLUSIONS: Among critically ill COVID-19 patients, 40% had restrictive patterns with decreased DLCO . The reduction of PFT was associated with MV, type of variants.

Prognosis of mechanically ventilated patients with COVID-19 after failure of high-flow nasal cannula: a retrospective cohort study.

BACKGROUND: There is an argument whether the delayed intubation aggravate the respiratory failure in Acute respiratory distress syndrome (ARDS) patients with coronavirus disease 2019 (COVID-19). We aimed to investigate the effect of high-flow nasal cannula (HFNC) failure before mechanical ventilation on clinical outcomes in mechanically ventilated patients with COVID-19. METHODS: This retrospective cohort study included mechanically ventilated patients who were diagnosed with COVID-19 and admitted to the intensive care unit (ICU) between February 2020 and December 2021 at Asan Medical Center. The patients were divided into HFNC failure (HFNC-F) and mechanical ventilation (MV) groups according to the use of HFNC before MV. The primary outcome of this study was to compare the worst values of ventilator parameters from day 1 to day 3 after mechanical ventilation between the two groups. RESULTS: Overall, 158 mechanically ventilated patients with COVID-19 were included in this study: 107 patients (67.7%) in the HFNC-F group and 51 (32.3%) in the MV group. The two groups had similar profiles of ventilator parameter from day 1 to day 3 after mechanical ventilation, except of dynamic compliance on day 3 (28.38 mL/cmH2O in MV vs. 30.67 mL/H2O in HFNC-F, p = 0.032). In addition, the HFNC-F group (5.6%) had a lower rate of ECMO at 28 days than the MV group (17.6%), even after adjustment (adjusted hazard ratio, 0.30; 95% confidence interval, 0.11-0.83; p = 0.045). CONCLUSIONS: Among mechanically ventilated COVID-19 patients, HFNC failure before mechanical ventilation was not associated with deterioration of respiratory failure.

Association between mechanical power and intensive care unit mortality in Korean patients under pressure-controlled ventilation.

BACKGROUND: Mechanical power (MP) has been reported to be associated with clinical outcomes. Because the original MP equation is derived from paralyzed patients under volume-controlled ventilation, its application in practice could be limited in patients receiving pressure-controlled ventilation (PCV). Recently, a simplified equation for patients under PCV was developed. We investigated the association between MP and intensive care unit (ICU) mortality. METHODS: We conducted a retrospective analysis of Korean data from the Fourth International Study of Mechanical Ventilation. We extracted data of patients under PCV on day 1 and calculated MP using the following simplified equation: MPPCV = 0.098 ∙ respiratory rate ∙ tidal volume ∙ (ΔPinsp + positive end-expiratory pressure), where ΔPinsp is the change in airway pressure during inspiration. Patients were divided into survivors and non-survivors and then compared. Multivariable logistic regression was performed to determine association between MPPCV and ICU mortality. The interaction of MPPCV and use of neuromuscular blocking agent (NMBA) was also analyzed. RESULTS: A total of 125 patients was eligible for final analysis, of whom 38 died in the ICU. MPPCV was higher in non-survivors (17.6 vs. 26.3 J/min, P<0.001). In logistic regression analysis, only MPPCV was significantly associated with ICU mortality (odds ratio, 1.090; 95% confidence interval, 1.029-1.155; P=0.003). There was no significant effect of the interaction between MPPCV and use of NMBA on ICU mortality (P=0.579). CONCLUSIONS: MPPCV is associated with ICU mortality in patients mechanically ventilated with PCV mode, regardless of NMBA use.

Effect of additional dead space using end-tidal CO2 measurement on ventilating preterm infants: An experimental study.

BACKGROUND: Dead space is the part of the airway where no gas exchange takes place. Any increase in dead space volume has a proportional effect on the required tidal volume and thus on the risk of ventilation-induced lung injury. Inserts that increase dead space are therefore not used in small preterm infants. This includes end-tidal CO2 measurement. OBJECTIVE: The aim of this study was to investigate the effect of the end-tidal CO2 measurement adapter on ventilation. METHODS: In an experimental setup, an end-tidal CO2 measurement adapter, three different pneumotachographs (PNT-A, PNT-B, PNT-Neo), and a closed suction adapter were combined in varying set-ups. The time required for CO2 elimination by a CO2-flooded preterm infant test lung was measured. RESULTS: PNT-A prolonged CO2 elimination time by 0.9 s (+3.3%), Neo-PNT by 3.2 s (+11.6%) and PNT-B by 9.0 s (+32.7%). The end-tidal CO2 measurement adapter prolonged the elimination time by an additional second without the pneumotachograph (+3.6%) and in combination with PNT-A (+3.1%) and PNT-Neo (+3.1%). In conjunction with PNT-B, the end-tidal CO2 measurement adapter reduced the elimination time by 0.3 seconds (-1%). The use of a closed suction adaptor increased the CO2 elimination time by a further second with PNT-Neo (+3.1%) and by an additional two seconds with no flow sensor (+6.9%), with PNT-A (+6.4%) and with PNT-B (+5.5%). CONCLUSION: The flow sensor had the greatest influence on ventilatory effort, while end-tidal CO2 measurement had only a moderate effect. The increased ventilatory effort levied by the CO2 measurement was dependent on the flow sensor selected. The use of closed suctioning more negatively impacted ventilatory effort than did end-tidal CO2 measurement.

Effect of fourth hourly oropharyngeal suctioning on ventilator-associated events in patients requiring mechanical ventilation in intensive care units of a tertiary care center in South India: a randomized controlled trial.

BACKGROUND: Mechanical ventilation (MV) is a necessary life-saving measure for critically ill patients. Ventilator-associated events (VAEs) are potentially avoidable complications associated with MV that can double the rate of death. Oral care and oropharyngeal suctioning, although neglected procedures, play a vital role in the prevention of VAE. METHODS: A randomized controlled trial was conducted in the intensive care units to compare the effect of fourth hourly oropharyngeal suctioning with the standard oral care protocol on VAE among patients on MV. One hundred twenty mechanically ventilated patients who were freshly intubated and expected to be on ventilator support for the next 72 hours were randomly allocated to the control or intervention groups. The intervention was fourth hourly oropharyngeal suctioning along with the standard oral care procedure. The control group received standard oral care (i.e., thrice a day) and on-demand oral suctioning. On the 3rd and 7th days following the intervention, endotracheal aspirates were sent to rule out ventilator-associated pneumonia. RESULTS: Both groups were homogenous at baseline with respect to their clinical characteristics. The intervention group had fewer VAEs (56.7%) than the control group (78.3%) which was significant at P<0.01. A significant reduction in the status of "positive culture" on ET aspirate also been observed following the 3rd day of the intervention (P<0.001). CONCLUSIONS: One of the most basic preventive strategies is providing oral care. Oropharyngeal suctioning is also an important component of oral care that prevents microaspiration. Hence, fourth-hourly oropharyngeal suctioning with standard oral care significantly reduces the incidence of VAE.

Exploring factors affecting the timely transition of ventilator assisted individuals in Ontario from acute to long-term care: Perspectives of healthcare professionals.

Rationale: Ventilator Assisted Individuals (VAIs) frequently remain in intensive care units (ICUs) for a prolonged period once clinically stable due to a lack of transition options. These VAIs occupy ICU beds and resources that patients with more acute needs could better utilize. Moreover, VAIs experience improved outcomes and quality of life in long-term and community-based environments. Objective: To better understand the perspectives of healthcare providers (HCPs) working in an Ontario ICU regarding barriers and facilitators to referral and transition of VAIs from the ICU to a long-term setting. Methods: We conducted semi-structured interviews with ten healthcare providers involved in VAI transitions. Main Results: Perceived barriers included long wait times for long-term care settings, insufficient bed availability at discharge locations, medical complexity of patients, long waitlists, and a lack of transparency of waitlists. Facilitators included strong partnerships and trusting relationships between referring and discharge locations, a centralized referral system, and utilization of community partnerships across care sectors. Conclusions: Insufficient resourcing of long-term care is a key barrier to transitioning VAIs from ICU to long-term settings; strong partnerships across care sectors are a facilitator. System-level approaches, such as a single-streamlined referral system, are needed to address key barriers to timely transition.

Enablers and barriers to adopt the locally developed Masi mechanical ventilator amid COVID-19 pandemic in Peru.

Background: Limited supply of resources during the COVID-19 emergency encouraged the local development of the Masi mechanical ventilator (MV). Despite the efforts to promote Masi, adopting this innovation faced multiple obstacles, regardless of its performance. We explored the perceptions among healthcare personnel towards incorporating Masi to provide ventilatory support to COVID-19 patients during the second wave in Peru (January to June 2021). Methods: We conducted twelve in-depth virtual interviews. Topics included experience when handling Masi, the impact of the training received, confidence in the device, barriers perceived, and enablers identified. All participants provided verbal informed consent. Results: Most of the participants were male physicians. Participants belonged to seven hospitals that exhibited a wide range of healthcare capacities. Globally, the adoption of Masi MV was driven by the scarcity of ventilatory devices in the wards and reinforced by appropriate training and prompt technical support. Participants reported that Masi's structural and operational features played both advantages and disadvantages. Hospital infrastructure readiness, availability of commercial MVs, mistrust in its simple appearance, and resistance to change among healthcare personnel were perceived as barriers, while low-cost, prompt technical support and user-friendliness were valuable enablers. The first two enablers were observed in participants regardless of their attitude towards Masi. Despite the small number of participants for this qualitative study, it is important to note that the sample size was sufficient to reach saturation, as the topics discussed with participants became redundant and did not yield new information. Conclusions: The perceptions among healthcare personnel to incorporate Masi as a mechanical ventilator for COVID-19 patients showed that communication, training and experience, and peer encouragement were essential to secure its use and sustainability of the technology. A priori judgments and perceptions unrelated to the performance of the novel device were observed, and its proper management may define its further implementation. Altogether our study suggests that along with strengthening local technological development, strategies to improve their adoption process must be considered as early as possible in medical innovations.

Longitudinal trajectories of sedation level and clinical outcomes in patients who are mechanically ventilated based on a group-based trajectory model: a prospective, multicentre, longitudinal and observational study in Korea.

OBJECTIVES: Changes in sedation levels over a long time in patients who are mechanically ventilated are unknown. Therefore, we investigated the long-term sedation levels of these patients by classifying them into different longitudinal patterns. DESIGN: This was a multicentre, prospective, longitudinal, and observational study. SETTING: Twenty intensive care units (ICUs) spanning several medical institutions in Korea. PARTICIPANTS: Patients who received mechanical ventilation and sedatives in ICU within 48 hours of admission between April 2020 and July 2021. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary objective of this study was to identify the pattern of sedation practice. Additionally, we analysed the associations of trajectory groups with clinical outcomes as the secondary outcome. RESULTS: Sedation depth was monitored using Richmond Agitation-Sedation Scale (RASS). A group-based trajectory model was used to classify 631 patients into four trajectories based on sedation depth: persistent suboptimal (13.2%, RASS ≤ -3 throughout the first 30 days), delayed lightening (13.9%, RASS ≥ -2 after the first 15 days), early lightening (38.4%, RASS ≥ -2 after the first 7 days) and persistent optimal (34.6%, RASS ≥ -2 during the first 30 days). 'Persistent suboptimal' trajectory was associated with delayed extubation (HR: 0.23, 95% CI: 0.16 to 0.32, p<0.001), longer ICU stay (HR: 0.36, 95% CI: 0.26 to 0.51, p<0.001) and hospital mortality (HR: 13.62, 95% CI: 5.99 to 30.95, p<0.001) compared with 'persistent optimal'. The 'delayed lightening' and 'early lightening' trajectories showed lower extubation probability (HR: 0.30, 95% CI: 0.23 to 0.41, p<0.001; HR: 0.72, 95% CI: 0.59 to 0.87, p<0.001, respectively) and ICU discharge (HR: 0.44, 95% CI: 0.33 to 0.59, p<0.001 and HR: 0.80, 95% CI: 0.65 to 0.97, p=0.024) compared with 'persistently optimal'. CONCLUSIONS: Among the four trajectories, 'persistent suboptimal' trajectory was associated with higher mortality.

Usability-Tests of Mechanical Ventilators: A Systematic Review.

The usability of ventilators is critical for patient safety. This systematic review shows the methods used in usability studies on ventilators, if those are similar in methodology. Furthermore, the usability tasks are compared to the requirements for manufactures during approval. Results show that the methodology and procedure of the studies are similar, but only cover part of the primary operating functions from their corresponding ISO Norm. Therefore optimisation of aspects of the study design, e.g., scope of tested scenarios, is possible.

Mechanical hyperinflation maneuver and intracranial compliance of critical neurological patients: protocol for a randomized controlled equivalence trial.

BACKGROUND: Mechanical hyperinflation maneuver (MHM) is a technique known for optimizing bronchial hygiene and respiratory mechanics; however, its effects on intracranial compliance are not known. METHODS: Sixty patients aged ≥ 18 years, with clinical diagnosis of acute stroke, confirmed by neuroimaging examination, with onset of symptoms within 72 h, under mechanical ventilation through tracheal tube, will participate in this study. Participants will be randomly allocated into 2 groups: experimental group (n = 30)-MHM plus tracheal aspiration-and control group (n = 30)-tracheal aspiration only. Intracranial compliance will be measured by a non-invasive technique using Brain4care BcMM-R-2000 sensor. This will be the primary outcome. Results will be recorded at 5 times: T0 (start of monitoring), T1 (moment before MHM), T2 (moment after the MHM and before tracheal aspiration), T3 (moment after tracheal aspiration), T4, and T5 (monitoring 10 and 20 min after T3). Secondary outcomes are respiratory mechanics and hemodynamic parameters. DISCUSSION: This study will be the first clinical trial to examine the effects and safety of MHM on intracranial compliance measured by non-invasive monitoring. Limitation includes the impossibility of blinding the physical therapist who will supervise the interventions. It is expected with this study to demonstrate that MHM can improve respiratory mechanics and hemodynamic parameters and provide a safe intervention with no changes in intracranial compliance in stroke patients.

Disparities in Adult Patient Selection for Extracorporeal Membrane Oxygenation in the United States: A Population-Level Study.

Rationale: Disparities in patient selection for advanced therapeutics in health care have been identified in multiple studies, but it is unclear if disparities exist in patient selection for extracorporeal membrane oxygenation (ECMO), a rapidly expanding critical care resource. Objectives: To determine if disparities exist in patient selection for ECMO based on sex, primary insurance, and median income of the patient's neighborhood. Methods: In a retrospective cohort study using the Nationwide Readmissions Database 2016-2019, we identified patients treated with mechanical ventilation (MV) and/or ECMO with billing codes. Patient sex, insurance, and income level for patients receiving ECMO were compared with the patients treated with MV only, and hierarchical logistic regression with the hospital as a random intercept was used to determine odds of receiving ECMO based on patient demographics. Results: We identified 2,170,752 MV hospitalizations with 18,725 cases of ECMO. Among patients treated with ECMO, 36.1% were female compared with 44.5% of patients treated with> MV only (adjusted odds ratio [aOR] for ECMO, 0.73; 95% confidence interval [CI], 0.70-0.75). Of patients treated with ECMO, 38.1% had private insurance compared with 17.4% of patients treated with MV only. Patients with Medicaid were less likely to receive ECMO than patients with private insurance (aOR, 0.55; 95% CI, 0.52-0.57). Patients treated with ECMO were more likely to live in the highest-income neighborhoods compared with patients treated with MV only (25.1% vs. 17.3%). Patients living in the lowest-income neighborhoods were less likely to receive ECMO than those living in the highest-income neighborhoods (aOR, 0.63; 95% CI, 0.60-0.67). Conclusions: Significant disparities exist in patient selection for ECMO. Female patients, patients with Medicaid, and patients living in the lowest-income neighborhoods are less likely to be treated with ECMO. Despite possible unmeasured confounding, these findings were robust to multiple sensitivity analyses. On the basis of previous work describing disparities in other areas of health care, we speculate that limited access in some neighborhoods, restrictive/biased interhospital transfer practices, differences in patient preferences, and implicit provider bias may contribute to the observed differences. Future studies with more granular data are needed to identify and modify drivers of observed disparities.

A novel approach in understanding the basic modes of ventilation in a recent generation mechanical ventilator- A review of the underlying principles.

Understanding the basic concepts and the dynamics of the equation of motion will help the anaesthesiologist and the intensive care physician in gaining an insight into the basics of modern mechanical ventilation. An equation of the type Vt = V0 × (1-e-kt) is often encountered while studying the concepts of mechanical ventilation. This leaves one wondering about the meaning of 'e'. It is explained as the base of a natural logarithm, and the base e as an irrational constant approximately equal to 2. 7182. In medical literature, various physiological mechanisms are explained by using the exponential function e. However, the explanations do not sufficiently help the learner to demystify the enigmatic term e. In this article, an effort is made to explain this function with the help of simple analogies and relevant mathematical concepts. The process of volume build-up in the lungs during mechanical ventilation is used as a model for the explanations.

Challenging Diagnosis of a Congenital Tracheal Malformation: Considerations From an Intensive Care Perspective.

Congenital tracheal stenosis is a rare airway malformation. A high index of suspicion is fundamental. The authors report a case of congenital tracheal stenosis in a 13-month-old male infant, with a challenging diagnosis from the intensive care perspective. At birth, the patient presented an anorectal malformation with a recto-urethral fistula so a colostomy with mucous fistula was performed in the neonatal period. At the age of seven months, he was admitted due to a respiratory infection, treated with steroids and bronchodilators, and discharged after three days without any complications. He underwent complete repair of tetralogy of Fallot when he was 11 months old, which was performed without any reported perioperative complications. However, at the age of 13 months, due to another respiratory infection, he presented more severe symptoms and required admission to the pediatric intensive care unit (PICU) for invasive mechanical ventilation. He was intubated on the first attempt. While monitoring the difference between peak inspiratory and plateau pressures, we observed a sustained elevated difference between pressures suggestive of increased airway resistance, thus raising the possibility of an anatomical obstruction. Laryngotracheoscopy confirmed distal tracheal stenosis (grade II) with four complete tracheal rings. In our case, the absences of perioperative challenges or complications in previous respiratory infections were not suggestive of a tracheal malformation. Furthermore, no difficulties were encountered during intubation due to the distal location of the tracheal stenosis. A careful appreciation of respiratory mechanics on the ventilator at rest and during tracheal aspirations was essential to suspect an anatomical defect.

Electric impedance tomography-guided PEEP titration reduces mechanical power in ARDS: a randomized crossover pilot trial.

BACKGROUND: In patients with acute respiratory distress syndrome undergoing mechanical ventilation, positive end-expiratory pressure (PEEP) can lead to recruitment or overdistension. Current strategies utilized for PEEP titration do not permit the distinction. Electric impedance tomography (EIT) detects and quantifies the presence of both collapse and overdistension. We investigated whether using EIT-guided PEEP titration leads to decreased mechanical power compared to high-PEEP/FiO2 tables. METHODS: A single-center, randomized crossover pilot trial comparing EIT-guided PEEP selection versus PEEP selection using the High-PEEP/FiO2 table in patients with moderate-severe acute respiratory distress syndrome. The primary outcome was the change in mechanical power after each PEEP selection strategy. Secondary outcomes included changes in the 4 × driving pressure + respiratory rate (4 ΔP, + RR index) index, driving pressure, plateau pressure, PaO2/FiO2 ratio, and static compliance. RESULTS: EIT was consistently associated with a decrease in mechanical power compared to PEEP/FiO2 tables (mean difference - 4.36 J/min, 95% CI - 6.7, - 1.95, p = 0.002) and led to lower values in the 4ΔP + RR index (- 11.42 J/min, 95% CI - 19.01, - 3.82, p = 0.007) mainly driven by a decrease in the elastic-dynamic power (- 1.61 J/min, - 2.99, - 0.22, p = 0.027). The elastic-static and resistive powers were unchanged. Similarly, EIT led to a statistically significant change in set PEEP (- 2 cmH2O, p = 0.046), driving pressure, (- 2.92 cmH2O, p = 0.003), peak pressure (- 6.25 cmH2O, p = 0.003), plateau pressure (- 4.53 cmH2O, p = 0.006), and static respiratory system compliance (+ 7.93 ml/cmH2O, p = 0.008). CONCLUSIONS: In patients with moderate-severe acute respiratory distress syndrome, EIT-guided PEEP titration reduces mechanical power mainly through a reduction in elastic-dynamic power. Trial registration This trial was prospectively registered on Clinicaltrials.gov (NCT03793842) on January 4th, 2019.

Infection-Related Ventilator-Associated Complications in Critically Ill Patients with Trauma: A Retrospective Analysis.

BACKGROUND: Trauma is a leading cause of death and disability. Patients with trauma undergoing invasive mechanical ventilation (IMV) are at risk for ventilator-associated events (VAEs) potentially associated with a longer duration of IMV and increased stay in the intensive care unit (ICU). METHODS: We conducted a retrospective cohort study aimed to evaluate the incidence of infection-related ventilator-associated complications (IVACs), possible ventilator-associated pneumonia (PVAP), and their characteristics among patients experiencing severe trauma that required ICU admission and IMV for at least four days. We also determined pathogens implicated in PVAP episodes and characterized the use of antimicrobial therapy. RESULTS: In total, 88 adult patients were included in the main analysis. In this study, we observed that 29.5% of patients developed a respiratory infection during ICU stay. Among them, five patients (19.2%) suffered from respiratory infections due to multi-drug resistant bacteria. Patients who developed IVAC/PVAP presented lower total GCS (median value, 7; (IQR, 9) vs. 12.5, (IQR, 8); p = 0.068) than those who did not develop IVAC/PVAP. CONCLUSIONS: We observed that less than one-third of trauma patients fulfilling criteria for ventilator associated events developed a respiratory infection during the ICU stay.

Distribuição da COVID-19 e dos recursos de saúde na Amazônia Legal: uma análise espacial / Distribution of COVID-19 cases and health resources in Brazil's Amazon region: a spatial analysis

Resumo O método de análise espacial permite mensurar a acessibilidade espacial dos serviços de saúde para alocação dos recursos de forma eficiente e eficaz. Diante disso, o objetivo deste estudo foi analisar a distribuição espacial das taxas de COVID-19 e dos recursos de saúde na Amazônia Legal. Estudo ecológico realizado com casos de COVID-19 e os recursos de saúde nos 772 municípios em dois picos da pandemia. Utilizou-se o método bayesiano global e local para elaboração de mapas coropléticos, com cálculo do índice de Moran para análise da dependência espacial e utilização do Moran map para identificação dos clusters da doença. Os índices de Moran calculados para os dois períodos demonstraram autocorrelação espacial positiva dessa distribuição e dependência espacial entre os municípios nos dois períodos, sem muita diferença entre os dois estimadores. Evidenciaram-se maiores taxas da doença nos estados do Amapá, Amazonas e Roraima. Em relação aos recursos de saúde, observou-se alocação de forma ineficiente, com maior concentração nas capitais.

Abstract Spatial analysis can help measure the spatial accessibility of health services with a view to improving the allocation of health care resources. The objective of this study was to analyze the spatial distribution of COVID-19 detection rates and health care resources in Brazil's Amazon region. We conducted an ecological study using data on COVID-19 cases and the availability of health care resources in 772 municipalities during two waves of the pandemic. Local and global Bayesian estimation were used to construct choropleth maps. Moran's I was calculated to detect the presence of spatial dependence and Moran maps were used to identify disease clusters. In both periods, Moran's I values indicate the presence of positive spatial autocorrelation in distributions and spatial dependence between municipalities, with only a slight difference between the two estimators. The findings also reveal that case rates were highest in the states of Amapá, Amazonas, and Roraima. The data suggest that health care resources were inefficiently allocated, with higher concentrations of ventilators and ICU beds being found in state capitals.

Disinfection efficacy of ozone on ESKAPE bacteria biofilms: Potential use in difficult-to-access medical devices.

BACKGROUND: Medical devices can be reservoirs of multidrug-resistant bacteria that may be involved in the acquisition of infections since bacteria with the ability to form biofilms that are difficult to eradicate, mainly in mechanical ventilators. The aim of this work was to evaluate the efficacy of O3 against biofilms of bacteria ESKAPE group through disinfection studies. METHODS: The formation of biofilms of ESKAPE group bacteria was induced in vitro. O3 was injected at different exposure times at a constant dose of 600 mg/h. The recovery of surviving bacteria after O3 treatment was assessed by bacterial counts and biofilm disruption was analyzed. Finally, the viability and integrity of biofilms after O3 treatment was determined by confocal laser scanning microscopy (CLSM). RESULTS: O3 showed bactericidal activity on biofilms from 12 min/7.68 ppm for A. baumannii and C. freundii. P. aeruginosa, K. pneumoniae and S. aureus were killed after 15 min/9.60 ppm. Correlation analyses showed inversely proportional relationships between the variables "disruption versus O3". CLSM revealed that death was time-dependent of biofilms upon O3 exposure. Orthogonal plane analysis showed that bacteria located in the outer region of the biofilms were the ones that initially suffered damage from O3 exposure. CONCLUSIONS: Our findings suggest that this method could be an alternative for the disinfection in mechanical ventilators colonized by bacteria biofilm forming.