Course Of Mechanical Ventilation Research Articles

Comparison of Web-Based and On-Site Lung Simulators for Education in Mechanical Ventilation.

Training in mechanical ventilation is a key goal in critical care fellowship education. Web-based simulators offer a cost-effective and readily available alternative to traditional on-site simulators. However, it is unclear how effective they are as teaching tools. In this study, we evaluated the test scores of fellows who underwent mechanical ventilation training by using a web-based simulator compared with fellows who used an on-site simulator during a mechanical ventilation course. This was a nonrandomized controlled trial conducted as part of a mechanical ventilation course that involved 70 first-year critical care fellows. The course was identical except for the simulation technology used. One group of instructors used a traditional on-site simulator, the ASL 5000 Lung Solution (n = 39). The second group was instructed in using a web-based simulator, VentSim (n = 31). Each fellow completed a pre-course test and a post-course test by using a validated, case-based ventilator waveform examination that consisted of 5 questions with a total possible score of 100. The primary outcome was a comparison of the mean scores on the posttest between the 2 groups. The study was designed as a non-inferiority trial with a predetermined margin of 10 points. There was no significant difference in the mean ± SD pretest scores between the web-based and the on-site groups (21.1 ± 12.6 and 26.9 ± 13.6 respectively; P = .11). The mean ± SD posttest scores were 45.6 ± 25.0 for the web-based simulator and 43.4 ± 16.5 for on-site simulator (mean difference 2.2; one-sided 95% CI -7.0 to ∞; P non-inferiority = .02 [non-inferiority confirmed]). Changes in mean ± SD scores (posttest - pretest) were 25.9 ± 20.9 for the web-based simulator and 16.5 ± 15.9 for the on-site simulator (mean difference 9.4, one-sided 95% CI 0.9 to ∞; P non-inferiority < .001 [non-inferiority confirmed]). In the education of first-year critical care fellows on mechanical ventilation waveform analysis, a web-based mechanical ventilation simulator was non-inferior to a traditional on-site mechanical ventilation simulator.

A short duration of mechanical ventilation alters redox status in the diaphragm and aggravates inflammation in septic mice

BackgroundMechanical ventilation (MV) is a life support method used to treat patients with respiratory failure. High tidal volumes during MV can cause ventilator-induced lung injury (VILI), but also affect other organs, such as the diaphragm (Dia) causing ventilator-induced diaphragmatic dysfunction (VIDD). VIDD is often associated with a complicated course on MV. Sepsis can induce inflammation and oxidative stress, contributing to the impairment of the Dia and worsening of the prognosis. This study evaluated the additive or synergistic effects of a short course of mechanical ventilation on Dia in healthy and septic adult mice. Methods32 adult male C57BL/6 mice were randomly into four groups: Control (CG), non-ventilated animals instilled with saline solution (PBS1x); Lipopolysaccharide (LPS), non-ventilated animals instilled with PBS solution containing lipopolysaccharide; Mechanical Ventilation (MV) for 1 h, ventilated animals instilled with PBS solution; and Mechanical Ventilation and LPS (MV+LPS), ventilated animals instilled with PBS solution containing LPS. At the end of the experimental protocol, the animals were euthanized, then blood and diaphragm tissue samples were collected. ResultsEvaluation of leukocyte/blood parameters and diaphragm muscle showed that MV, LPS and the combination of both were able to increase neutrophil count, creatine kinase, inflammatory mediators and oxidative stress in all groups compared to the control. MV and sepsis combined had additive effects on inflammation and lipid peroxidation. ConclusionsA short course of Mechanical ventilation promotes inflammation and oxidative stress and, its combination with sepsis further increases local and systemic inflammation.

Effect of different courses and durations of invasive mechanical ventilation on respiratory outcomes in very low birth weight infants

This multicenter retrospective study was conducted to explore the effects of different courses and durations of invasive mechanical ventilation (MV) on the respiratory outcomes of very low birth weight infants (VLBWI) in China. The population for this study consisted of infants with birth weight less than 1500 g needing at least 1 course of invasive MV and admitted to the neonatal intensive care units affiliated with the Chinese Neonatal Network within 6 h of life from January 1st, 2019 to December 31st, 2020. Univariate and multivariate logistic regression analyses were performed to evaluate associations between invasive MV and respiratory outcomes. Adjusted odds ratios (ORs) were computed with the effects of potential confounders. (1) Among the 3183 VLBWs with a history of at least one course of invasive MV, 3155 (99.1%) met inclusion criteria and were assessed for the primary outcome. Most infants received one course (76.8%) and a shorter duration of invasive MV (62.16% with ventilation for 7 days or less). (2) In terms of the incidence of all bronchopulmonary dysplasia (BPD) (mild, moderate, and severe BPD), there were no significant differences between different invasive MV courses [For 2 courses, adjusted OR = 1.11 (0.88, 1.39); For 3 courses or more, adjusted OR = 1.07 (0.72, 1.60)]. But, with the duration of invasive MV prolonging, the OR of BPD increased [8–21 days, adjusted OR = 1.98 (1.59, 2.45); 22–35 days, adjusted OR = 4.37 (3.17, 6.03); ≥ 36 days, adjusted OR = 18.44 (10.98, 30.99)]. Concerning severe BPD, the OR increased not only with the course of invasive MV but also with the duration of invasive MV [For 2 courses, adjusted OR = 2.17 (1.07, 4.40); For 3 courses or more, adjusted OR = 2.59 (1.02, 6.61). 8–21 days, adjusted OR = 8.42 (3.22, 22.01); 22–35 days, adjusted OR = 27.82 (9.08, 85.22); ≥ 36 days, adjusted OR = 616.45 (195.79, > 999.999)]. (3) When the interaction effect between invasive MV duration and invasive MV course was considered, it was found that there were no interactive effects in BPD and severe BPD. Greater than or equal to three courses would increase the chance of severe BPD, death, and the requirement of home oxygen therapy. Compared with distinct courses of invasive MV, a longer duration of invasive MV (> 7 days) has a greater effect on the risk of BPD, severe BPD, death, and the requirement of home oxygen therapy.

Unplanned Extubation During Pediatric Cardiac Intensive Care: U.S. Multicenter Registry Study of Prevalence and Outcomes.

The epidemiology of unplanned extubations (UEs) and associated adverse outcomes in pediatric cardiac ICUs (CICU). Registry data (August 2014 to October 2020). Forty-five Pediatric Cardiac Critical Care Consortium hospitals. Patients receiving mechanical ventilation (MV) via endotracheal tube (ETT). None. Fifty-six thousand five hundred eight MV courses occurred in 36,696 patients, with a crude UE rate of 2.8%. In cardiac surgical patients, UE was associated with longer duration of MV, but we failed to find such association in medical patients. In both cohorts, UE was associated with younger age, being underweight, and airway anomaly. In multivariable logistic regression, airway anomaly was associated with UE in all patients. Younger age, higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery score category, longer duration of MV, and initial oral rather than nasal ETT are associated with UE in the surgical group, but we failed to find such associations in the medical group. UE was associated with a higher reintubation rate compared with elective extubation (26.8 vs 4.8%; odds ratio [OR], 7.35; 95% CI, 6.44-8.39; p < 0.0001) within 1 day of event. After excluding patients having redirection of care, UE was associated with at least three-fold greater odds for each of ventilator-associated pneumonia (VAP), cardiac arrest, and use of mechanical circulatory support (MCS). However, we failed to identify an association between UE and greater odds of mortality (1.2 vs 0.8%; OR, 1.48; 95% CI, 0.86-2.54; p = 0.15), but uncertainty remains. UE in CICU patients is associated with greater odds of cardiac arrest, VAP, and MCS. Cardiac medical and surgical patients in the CICU appear to have different explanatory factors associated with UE, and perhaps these may be modifiable and tested in future collaborative population research.

Barotrauma in a Previously Healthy and Young COVID-19 Patient: an Autopsy Case Report

Abstract Introduction/Objective Since the emergence of a novel SARS-CoV-2 virus caused coronavirus disease 2019 (COVID-19), a great number of autopsy studies have been published. However, histopathologic studies focused on pulmonary barotrauma are very rare. Here we report an autopsy confined to the lungs on a young COVID-19 patient. Methods/Case Report The patient was a 37-year-old male, non-smoker, with no significant past medical history, and a body mass index of 24.1, who presented with shortness of breath and cough. A computerized tomography (CT) showed features of atypical pneumonia. The main abnormal laboratory data included elevated partial thromboplastin time, fibrinogen, and D-Dimer. The patient had been on mechanical ventilation for 35 days, and was complicated by recurrent pneumothoraces, hypotension, and worsening hypoxia. An autopsy limited to the lungs was performed after the patient expired. Grossly, the lungs showed increased weight, adhesions on visceral pleural surface, patchy consolidation and dilated subpleural cysts. Histological examination revealed cystically dilated/remodeled airspaces with extensive coagulative necrosis, focal alveolar hemorrhage and edema, focal confluent fibrosis, and subpleural blebs. Fresh fibrinous thrombi were seen in small- and medium-sized vessels. Viral cytopathic changes or significant inflammation were not observed. The findings in the lungs were consistent with barotrauma in COVID-19. Results (if a Case Study enter NA) NA. Conclusion This case demonstrates various histopathologic changes of the lungs in a previously healthy and young COVID-19 patient with prolonged hospital course of mechanical ventilation. The features of diffuse alveolar damage with inflammation usually seen in the early stage of barotrauma are not identified. Our findings in the lungs may represent the histopathologic characteristics of the later stage of barotrauma in COVID-19.

Design a simulating lung in 36h or less

Background: During the COVID health crisis, intensive care units were quickly overwhelmed and had to call for help. The only solution was to call for this help among nurses, nursing auxiliaries, and physicians that were normally not working in the ICU units (consultations, operating room, medical units). These people needed mechanical ventilation courses before beginning their job in the ICU unit. Simulation appeared to be the best solution because of its safety and educational effectiveness. Approach: We developed an artificial lung during the 36 hours innovation marathon Crunch Maker Camp 2021. It included three main settings which were lung compliance, airways resistances, and diaphragmatic inspiratory trigger. These parameters seemed to be essential for us in order to simulate the mechanical ventilation characteristics of a COVID lung. The simulator was entirely made of physical components. Evaluation: The team composed of engineers and intensive care medical instructors developed the first proof of concept of the artificial lung. The different controllable modules were able to adjust compliance, and resistance on the respirator, and an inspiratory trigger was efficient. They reflected correctly a normal or a COVID lung, simulating a patient on a ventilator. The simulator was presented to the jury and after deliberation, the teams’ work was rewarded with the first innovation prize. Reflection: We designed a controlled simulation for COVID respiratory issues; the artificial lung was rewarded during this innovation marathon Crunch Maker Camp 2021. This allowed us to improve the simulator and we plan to start using this tool during training sessions soon. We will then measure Pedagogic impact, focusing on long-term memorization.

Impact of a Mechanical Ventilation Curriculum on Respiratory Therapist Recognition of Patient-Ventilator Asynchrony.

Respiratory therapists (RTs) play a crucial role in managing mechanically ventilated patients, such as addressing patient-ventilator asynchronies that may contribute to patient harm. Waveform analysis is integral to the evaluation of patient-ventilator asynchronies; despite this, no published studies have assessed the ability of practicing RTs to interpret ventilator waveform abnormalities. The study took place between June 2017-February 2019. Eighty-six RTs from 2 academic medical centers enrolled in a one-day mechanical ventilation course. The scores of 79 first-time attendees were included in the analysis. Prior to and following the course, RTs were asked to identify abnormalities on a 5-question, multiple-choice ventilator waveform exam. They were also asked to provide a self-assessment of their ventilator management skills on a 1 (complete novice) to 5 (expert) scale. Initial scores were low but improved after one day of ventilator instruction (19.4 ± 17.1 vs 29.6 ± 19.0, P < .001). No significant difference was noted in mean confidence levels between the pre- and post-course assessments (3.8 ± 0.9 vs 3.8 ± 1.0, P = .56). RTs with fewer years of clinical experience (0-10 y) had a statistically significant improvement in their post-course test scores relative to their pre-course scores (0-5 y: 12.5 ± 10.1 to 46.0 ± 10.8, P < .001; 6-10 y: 18.7 ± 15.8 to 32.1 ± 16.7, P = .02), whereas those with > 11 y of clinical experience did not (11-20 y: 22.4 ± 15.5 to 27.4 ± 19.0, P = .44; 21+ y: 19.6 ± 22.1 to 15.3 ± 13.8, P = .50). RTs may benefit from additional training in ventilator waveform interpretation, especially early in their clinical training. More work is needed to determine the optimal length and content of a mechanical ventilation curriculum for RTs.

High Yield Pedagogy and FOAM as Dynamic Drivers of Building Human Capital and Successful Pandemic Rapid Responses in a Low Middle Income Country

PurposeWe hypothesized that utilizing a High Yield Pedagogy Model of our own design would result in a successful self-sufficient pandemic response capacity in a Resource Limited Environment by promoting rapid upscaling of skilled clinician-educators and complex knowledge translation into clinical practice.Methods & MaterialsIn response to the eruption of SARS-CoV2 in Guyana, which resulted in a surge of patients combined with a paucity of trained Critical-Care Medicine / Pulmonology Providers, we developed a blended learning Mechanical Ventilation course to rapidly upscale Human Capital and Critical-Care Medicine capacity. Our course primarily utilizes U.S. Special Operations Medicine Force Multiplier Train the Trainer strategies combined with a dynamic flipped classroom High Yield Pedagogy approach based in cognitive neuroscience to optimize rapid knowledge acquisition, retention and translation into clinical practice. We incorporated two on-line Free Open Access Meducation (FOAM) resources (one purely didactic and the other a ventilator simulator), several novel self-study clinical scenarios that dynamically progressed in tandem with assigned learning, and we culminated with an in person clinician-student driven intensive scenario based training (SBT) exercise in which each student was not only required to present a variety of complex cases, but also to effectively conduct training in an environment emphasizing Psychological Safety, Dynamic Process Improvement and a continuum of 360 degree feedback mechanisms.ResultsOur High Yield Pedagogy model rapidly and successfully produced a sustainable and self-sufficient Critical-Care Medicine Capacity. We were able to provide comprehensive just in time, turnkey SARS-CoV2 Mechanical Ventilation didactic and clinical training for Guyana's Ministry of Health, which in turn allowed them to dynamically pivot, rapidly upscale human capital, and successfully manage their initial surge of COVID-19 patients.ConclusionHigh Yield Pedagogy with a focus on sustainable self-sufficiency utilizing a flipped classroom, FOAM, and Psychological Safety is an effective mechanism to promote rapid knowledge translation and upscaling to increase critical-care capacity and optimize complex clinical outcomes under pandemic surge conditions in Low Middle Income Countries and severely Resource Limited Environments.

Mechanical ventilation promotes lung tumour spread by modulation of cholesterol cell content.

Mechanical stretch of cancer cells can alter their invasiveness. During mechanical ventilation, lungs may be exposed to an increased amount of stretch, but the consequences on lung tumours have not been explored. To characterise the influence of mechanical ventilation on the behaviour of lung tumours, invasiveness assays and transcriptomic analyses were performed in cancer cell lines cultured in static conditions or under cyclic stretch. Mice harbouring lung melanoma implants were submitted to mechanical ventilation and metastatic spread was assessed. Additional in vivo experiments were performed to determine the mechanodependent specificity of the response. Incidence of metastases was studied in a cohort of lung cancer patients that received mechanical ventilation compared with a matched group of nonventilated patients. Stretch increases invasiveness in melanoma B16F10luc2 and lung adenocarcinoma A549 cells. We identified a mechanosensitive upregulation of pathways involved in cholesterol processing in vitro, leading to an increase in pro-protein convertase subtilisin/kexin type 9 (PCSK9) and LDLR expression, a decrease in intracellular cholesterol and preservation of cell stiffness. A course of mechanical ventilation in mice harbouring melanoma implants increased brain and kidney metastases 2 weeks later. Blockade of PCSK9 using a monoclonal antibody increased cell cholesterol and stiffness and decreased cell invasiveness in vitro and metastasis in vivo. In patients, mechanical ventilation increased PCSK9 abundance in lung tumours and the incidence of metastasis, thus decreasing survival. Our results suggest that mechanical stretch promote invasiveness of cancer cells, which may have clinically relevant consequences. Pharmacological manipulation of cholesterol endocytosis could be a novel therapeutic target in this setting.

Focal Peripheral Neuropathies Observed in Patients Diagnosed With COVID-19: A Case Series.

A growing number of studies have documented a wide variety of neurological manifestations associated with the novel SARS-CoV-2 (COVID-19). Of the available literature, cranial neuropathies and central nervous system disorders, such as encephalopathy and ischemic strokes, remain the predominant discussion. Limited investigations exist examining peripheral neuropathies of those with COVID-19. This case series discusses eight patients who tested positive for COVID-19 and presented with localized weakness after a prolonged course of mechanical ventilation (>21 days). We retrospectively reviewed all patients' charts who received electrodiagnostic evaluation between March and November 2020 in the outpatient clinic or in the acute care hospital at the JFK Medical Center/JFK Johnson Rehabilitation Institute and Saint Peter's University Hospital of New Jersey. A total of eight COVID-19-positive patients were identified to have a clinical presentation of localized weakness after a prolonged course of mechanical ventilation. All patients were subsequently found to have a focal peripheral neuropathy of varying severity that was confirmed by electrodiagnostic testing. Patient demographics, clinical, and electrodiagnostic findings were documented. The findings of local weakness and focal peripheral neuropathies after diagnosis of COVID-19 raise significant questions regarding underlying pathophysiology and overall prognosis associated with COVID-19.

COVID-19 ARDS: Points to Be Considered in Mechanical Ventilation and Weaning.

The COVID-19 disease can cause hypoxemic respiratory failure due to ARDS, requiring invasive mechanical ventilation. Although early studies reported that COVID-19-associated ARDS has distinctive features from ARDS of other causes, recent observational studies have demonstrated that ARDS related to COVID-19 shares common clinical characteristics and respiratory system mechanics with ARDS of other origins. Therefore, mechanical ventilation in these patients should be based on strategies aiming to mitigate ventilator-induced lung injury. Assisted mechanical ventilation should be applied early in the course of mechanical ventilation by considering evaluation and minimizing factors associated with patient-inflicted lung injury. Extracorporeal membrane oxygenation should be considered in selected patients with refractory hypoxia not responding to conventional ventilation strategies. This review highlights the current and evolving practice in managing mechanically ventilated patients with ARDS related to COVID-19.

A low-cost field ventilator: An urgent global need.

Modern ventilators are increasingly compact and able to deliver a wide range of ventilator modes and sophisticated monitoring capabilities. However, the global availability of ventilators is woefully short of demand. Data on intensive care units (ICUs), a proxy measure for hospital ventilator capacity in low and middle‐income countries (LMIC's), suggest that capacity is extremely limited where it exists at all. In LMIC's, the four most common indications for mechanical ventilation (MV) in ICUs are post‐surgical care, sepsis, trauma, and maternal peripartum or neonatal complications. A significant majority of these cases can be managed with intervention involving a short course of MV. Widespread and timely access to MV can thus effectively be used to help patients in these settings and improve outcomes. This paper implores this need and highlights the requirements for a low‐cost ventilator or a respiratory support device.

Risk factors for adverse outcomes during mechanical ventilation of 1152 COVID-19 patients: a multicenter machine learning study with highly granular data from the Dutch Data Warehouse

BackgroundThe identification of risk factors for adverse outcomes and prolonged intensive care unit (ICU) stay in COVID-19 patients is essential for prognostication, determining treatment intensity, and resource allocation. Previous studies have determined risk factors on admission only, and included a limited number of predictors. Therefore, using data from the highly granular and multicenter Dutch Data Warehouse, we developed machine learning models to identify risk factors for ICU mortality, ventilator-free days and ICU-free days during the course of invasive mechanical ventilation (IMV) in COVID-19 patients.MethodsThe DDW is a growing electronic health record database of critically ill COVID-19 patients in the Netherlands. All adult ICU patients on IMV were eligible for inclusion. Transfers, patients admitted for less than 24 h, and patients still admitted at time of data extraction were excluded. Predictors were selected based on the literature, and included medication dosage and fluid balance. Multiple algorithms were trained and validated on up to three sets of observations per patient on day 1, 7, and 14 using fivefold nested cross-validation, keeping observations from an individual patient in the same split.ResultsA total of 1152 patients were included in the model. XGBoost models performed best for all outcomes and were used to calculate predictor importance. Using Shapley additive explanations (SHAP), age was the most important demographic risk factor for the outcomes upon start of IMV and throughout its course. The relative probability of death across age values is visualized in Partial Dependence Plots (PDPs), with an increase starting at 54 years. Besides age, acidaemia, low P/F-ratios and high driving pressures demonstrated a higher probability of death. The PDP for driving pressure showed a relative probability increase starting at 12 cmH2O.ConclusionAge is the most important demographic risk factor of ICU mortality, ICU-free days and ventilator-free days throughout the course of invasive mechanical ventilation in critically ill COVID-19 patients. pH, P/F ratio, and driving pressure should be monitored closely over the course of mechanical ventilation as risk factors predictive of these outcomes.

120 A Survey of Burn Care Professionals to Characterize Patterns of Early Mobility in ICU Burn Patients

Abstract Introduction Early mobility in intensive care unit (ICU) patients has been demonstrated effective in improving functional status, range of motion, preventing complications, and decreasing length of stay. There is limited data regarding the early mobilization of burn ICU patients. The purpose of this study was to survey burn care providers to better understand their experience with early mobilization and explore perceived barriers and contraindications. Methods An internet-based 21-item survey was distributed to burn professionals at North American burn centers and units. Descriptive statistics were performed. Results There were a total of 63 respondents. Most respondents were physical therapists (33%), occupational therapists (33%), or nurses (25%), with &amp;gt;5 years of burn care experience (71%). Early mobility was characterized as both in bed and out of bed activities within 24 hours of ICU admission, up to any time during the course of mechanical ventilation or ICU stay. The majority of respondents (54%) indicated they mobilize patients on ventilators in bed and out of bed, while there was an even split on whether or not patients on vasopressor support were mobilized. Of those respondents (46%) who use the Richmond Agitation-Sedation Scale (RASS) to guide mobility, 14% mobilize patients with a RASS of -4 or -5 and 41% mobilize patients with a RASS of -3 to -2. The highest appropriate score for mobilization was +1 to +2 (76%). Hgb/Hct, line presence, ventilator mode, mental status, and vital signs were viewed as precautions to discuss with the medical team, rather than a contraindication to mobility. Respiratory rate &amp;lt; 6 and presence of ECMO were the areas of most concern, with the majority respondents indicating they would likely hold mobility. Most respondents indicated that they would mobilize any burn ICU patients after discussion with the medical team if necessary. The majority of respondents (72%) indicated that they did not have an early mobilization protocol for burn ICU patients. Conclusions There is a paucity of evidence available for early mobility in burn ICU patients. This survey demonstrates a lack of consensus regarding what constitutes early mobility and when patients should be mobilized. A multi-center observational trial is needed to inform the development of an evidence-based mobility protocol.

Factors associated with progression to infection in methicillin-resistant Staphylococcus aureus-colonized, critically ill neonates.

ObjectiveTo identify factors associated with development of symptomatic infection in infants colonized with methicillin-resistant Staphylococcus aureus (MRSA) in the Neonatal Intensive Care Unit (NICU).Study designThis case-control study was performed at St. Louis Children’s Hospital NICU from 2009 to 2019. The MRSA-colonized infants who developed symptomatic MRSA infection (cases) were matched 1:3 with MRSA-colonized infants who did not develop infection (controls). Demographics and characteristics of NICU course were compared between groups. Longitudinal information from subsequent hospitalizations was also obtained.ResultsForty-two infected cases were compared with 126 colonized-only controls. Cases became colonized earlier in their NICU stay, were less likely to have received mupirocin for decolonization, and had a longer course of mechanical ventilation than controls. Longitudinally, cases had a more protracted NICU course and were more likely to require hospital readmission.ConclusionProgression from MRSA colonization to symptomatic infection is associated with increased morbidity and may be mitigated through decolonization.

Diaphragm echodensity in mechanically ventilated patients: a description of technique and outcomes.

BackgroundAcute increases in muscle sonographic echodensity reflect muscle injury. Diaphragm echodensity has not been measured in mechanically ventilated patients. We undertook to develop a technique to characterize changes in diaphragm echodensity during mechanical ventilation and to assess whether these changes are correlated with prolonged mechanical ventilation.MethodsDiaphragm ultrasound images were prospectively collected in mechanically ventilated patients and in 10 young healthy subjects. Echodensity was quantified based on the right-skewed distribution of grayscale values (50th percentile, ED50; 85th percentile, ED85). Intra- and inter-analyzer measurement reproducibility was determined. Outcomes recorded included duration of ventilation and ICU complications (including reintubation, tracheostomy, prolonged ventilation, or death).ResultsEchodensity measurements were obtained serially in 34 patients comprising a total of 104 images. Baseline (admission) diaphragm ED85 was increased in mechanically ventilated patients compared to younger healthy subjects (median 56, interquartile range (IQR) 42–84, vs. 39, IQR 36–52, p = 0.04). Patients with an initial increase in median echodensity over time (≥ + 10 in ED50 from baseline) had fewer ventilator-free days to day 60 (n = 13, median 46, IQR 0–52) compared to patients without this increase (n = 21, median 53 days, IQR 49–56, unadjusted p = 0.03). Both decreases and increases in diaphragm thickness during mechanical ventilation were associated with increases in ED50 over time (adjusted p = 0.03, conditional R2 = 0.80) and the association between increase in ED50 and outcomes persisted after adjusting for changes in diaphragm thickness.ConclusionsMany patients exhibit increased diaphragm echodensity at the outset of mechanical ventilation. Increases in diaphragm echodensity during the early course of mechanical ventilation are associated with prolonged mechanical ventilation. Both decreases and increases in diaphragm thickness during mechanical ventilation are associated with increased echodensity.

Subglottic suction frequency and adverse ventilator-associated events during critical illness.

Tracheal intubation and mechanical ventilation provide essential support for patients with respiratory failure, but the course of mechanical ventilation may be complicated by adverse ventilator-associated events (VAEs), which may or may not be associated with infection. We sought to understand how the frequency of subglottic suction, an indicator of the quantity of sputum produced by ventilated patients, relates to the onset of all VAEs and infection-associated VAEs. We performed a case-crossover study including 87 patients with VAEs, and we evaluated 848 days in the pre-VAE period at risk for a VAE. Critically ill patients were recruited from the medical intensive care unit of an academic medical center. We used the number of as-needed subglottic suctioning events performed per calendar day to quantify sputum production, and we compared the immediate pre-VAE period to the preceding period. We used CDC surveillance definitions for VAE and to categorize whether events were infection associated or not. Sputum quantity measured by subglottic suction frequency is greater in the period immediately prior to VAE than in the preceding period. However, it does not discriminate well between infection-associated VAEs and VAEs without associated infection. Subglottic suction frequency may serve as a valuable marker of sputum quantity, and it is associated with risk of a VAE. However, our results require validation in a broader population of mechanically ventilated patients and intensive care settings.

Duration of diaphragmatic inactivity after endotracheal intubation of critically ill patients

BackgroundIn patients intubated for mechanical ventilation, prolonged diaphragm inactivity could lead to weakness and poor outcome. Time to resume a minimal diaphragm activity may be related to sedation practice and patient severity.MethodsProspective observational study in critically ill patients. Diaphragm electrical activity (EAdi) was continuously recorded after intubation looking for resumption of a minimal level of diaphragm activity (beginning of the first 24 h period with median EAdi > 7 µV, a threshold based on literature and correlations with diaphragm thickening fraction). Recordings were collected until full spontaneous breathing, extubation, death or 120 h. A 1 h waveform recording was collected daily to identify reverse triggering.ResultsSeventy-five patients were enrolled and 69 analyzed (mean age ± standard deviation 63 ± 16 years). Reasons for ventilation were respiratory (55%), hemodynamic (19%) and neurologic (20%). Eight catheter disconnections occurred. The median time for resumption of EAdi was 22 h (interquartile range 0–50 h); 35/69 (51%) of patients resumed activity within 24 h while 4 had no recovery after 5 days. Late recovery was associated with use of sedative agents, cumulative doses of propofol and fentanyl, controlled ventilation and age (older patients receiving less sedation). Severity of illness, oxygenation, renal and hepatic function, reason for intubation were not associated with EAdi resumption. At least 20% of patients initiated EAdi with reverse triggering.ConclusionLow levels of diaphragm electrical activity are common in the early course of mechanical ventilation: 50% of patients do not recover diaphragmatic activity within one day. Sedatives are the main factors accounting for this delay independently from lung or general severity.Trial Registration ClinicalTrials.gov (NCT02434016). Registered on April 27, 2015. First patients enrolled June 2015.

Outcome of acute hypoxaemic respiratory failure: insights from the LUNG SAFE Study.

Current incidence and outcome of patients with acute hypoxaemic respiratory failure requiring mechanical ventilation in the intensive care unit (ICU) are unknown, especially for patients not meeting criteria for acute respiratory distress syndrome (ARDS). An international, multicentre, prospective cohort study of patients presenting with hypoxaemia early in the course of mechanical ventilation, conducted during four consecutive weeks in the winter of 2014 in 459 ICUs from 50 countries (LUNG SAFE). Patients were enrolled with arterial oxygen tension/inspiratory oxygen fraction ratio ≤300 mmHg, new pulmonary infiltrates and need for mechanical ventilation with a positive end-expiratory pressure of ≥5 cmH2O. ICU prevalence, causes of hypoxaemia, hospital survival and factors associated with hospital mortality were measured. Patients with unilateral versus bilateral opacities were compared. 12 906 critically ill patients received mechanical ventilation and 34.9% with hypoxaemia and new infiltrates were enrolled, separated into ARDS (69.0%), unilateral infiltrate (22.7%) and congestive heart failure (CHF; 8.2%). The global hospital mortality was 38.6%. CHF patients had a mortality comparable to ARDS (44.1% versus 40.4%). Patients with unilateral-infiltrate had lower unadjusted mortality, but similar adjusted mortality compared to those with ARDS. The number of quadrants on chest imaging was associated with an increased risk of death. There was no difference in mortality comparing patients with unilateral-infiltrate and ARDS with only two quadrants involved. More than one-third of patients receiving mechanical ventilation have hypoxaemia and new infiltrates with a hospital mortality of 38.6%. Survival is dependent on the degree of pulmonary involvement whether or not ARDS criteria are reached.

A Respiratory Therapist-Driven Pathway Improves Timeliness of Extubation Readiness Assessment in a Single PICU.

Our smart aim was to decrease the time between when a mechanically ventilated patient was eligible for and when they underwent their first extubation readiness test (delta time) by 50% within 3 months through the development and implementation of a respiratory therapist-driven extubation readiness test pathway. Quality improvement project. Single, tertiary care, 24-bed, academic PICU. Pediatric patients admitted to the PICU and requiring mechanical ventilation for a primary pulmonary process. We developed an extubation readiness test pathway that consisted of an eligibility screen and a standard testing process. Patients were screened every 3 hours. Upon passing the screen and being cleared by a prescriber, a test was initiated. No clinical management was dictated to prescribers. The preintervention and intervention cohorts included 109 and 43 mechanical ventilation courses, respectively. The mean delta time decreased from 33.77 hours to 2.92 hours after pathway implementation (p = 0.000). The medical length of stay decreased from 196.6 to 177.2 hours (p = 0.05). There were no statistically significant changes in duration of mechanical ventilation until first extubation (112.9 vs 122.3 hr; p = 0.651) and 48-hour extubation failure rate (16.5% vs 4.8%; p = 0.056). The sensitivity and positive predictive value for the extubation readiness test were 89.5% and 94.4%, respectively. The mean for all process compliance measures was 91.5%. A respiratory therapist-driven extubation readiness test pathway can be safely implemented in a large, academic PICU. The pathway resulted in earlier extubation readiness testing without increasing key balancing measures-the duration of mechanical ventilation, PICU length of stay, or the extubation failure rate.