Week Of Mechanical Ventilation Research Articles

Multicentric investigations of the role in the disease severity of accelerated phospholipid changes in COVID-19 patient airway

ContextThe changes in host membrane phospholipids are crucial in airway infection pathogenesis. Phospholipase A2 hydrolyzes host cell membranes, producing lyso-phospholipids and free fatty acids, including arachidonic acid (AA), which contributes significantly to lung inflammation. AimFollow these changes and their evolution from day 1, day 3 to day 7 in airway aspirates of 89 patients with COVID-19-associated acute respiratory distress syndrome and examine whether they correlate with the severity of the disease. The patients were recruited in three French intensive care units. The analysis was conducted from admission to the intensive care unit until the end of the first week of mechanical ventilation. ResultsIn the airway aspirates, we found significant increases in the levels of host cell phospholipids, including phosphatidyl-serine and phosphatidyl-ethanolamine, and their corresponding lyso-phospholipids. This was accompanied by increased levels of AA and its inflammatory metabolite prostaglandin E2 (PGE2). Additionally, enhanced levels of ceramides, sphingomyelin, and free cholesterol were observed in these aspirates. These lipids are known to be involved in cell death and/or apoptosis, whereas free cholesterol plays a role in virus entry and replication in host cells. However, there were no significant changes in the levels of dipalmitoyl-phosphatidylcholine, the major surfactant phospholipid. A correlation analysis revealed an association between mortality risk and levels of AA and PGE2, as well as host cell phospholipids. ConclusionOur findings indicate a correlation between heightened cellular phospholipid modifications and variations in AA and PGE2 with the severity of the disease in patients. Nevertheless, there is no indication of surfactant alteration in the initial phases of the illness.

Utilization of mechanical power and associations with clinical outcomes in brain injured patients: a secondary analysis of the extubation strategies in neuro-intensive care unit patients and associations with outcome (ENIO) trial

BackgroundThere is insufficient evidence to guide ventilatory targets in acute brain injury (ABI). Recent studies have shown associations between mechanical power (MP) and mortality in critical care populations. We aimed to describe MP in ventilated patients with ABI, and evaluate associations between MP and clinical outcomes.MethodsIn this preplanned, secondary analysis of a prospective, multi-center, observational cohort study (ENIO, NCT03400904), we included adult patients with ABI (Glasgow Coma Scale ≤ 12 before intubation) who required mechanical ventilation (MV) ≥ 24 h. Using multivariable log binomial regressions, we separately assessed associations between MP on hospital day (HD)1, HD3, HD7 and clinical outcomes: hospital mortality, need for reintubation, tracheostomy placement, and development of acute respiratory distress syndrome (ARDS).ResultsWe included 1217 patients (mean age 51.2 years [SD 18.1], 66% male, mean body mass index [BMI] 26.3 [SD 5.18]) hospitalized at 62 intensive care units in 18 countries. Hospital mortality was 11% (n = 139), 44% (n = 536) were extubated by HD7 of which 20% (107/536) required reintubation, 28% (n = 340) underwent tracheostomy placement, and 9% (n = 114) developed ARDS. The median MP on HD1, HD3, and HD7 was 11.9 J/min [IQR 9.2–15.1], 13 J/min [IQR 10–17], and 14 J/min [IQR 11–20], respectively. MP was overall higher in patients with ARDS, especially those with higher ARDS severity. After controlling for same-day pressure of arterial oxygen/fraction of inspired oxygen (P/F ratio), BMI, and neurological severity, MP at HD1, HD3, and HD7 was independently associated with hospital mortality, reintubation and tracheostomy placement. The adjusted relative risk (aRR) was greater at higher MP, and strongest for: mortality on HD1 (compared to the HD1 median MP 11.9 J/min, aRR at 17 J/min was 1.22, 95% CI 1.14–1.30) and HD3 (1.38, 95% CI 1.23–1.53), reintubation on HD1 (1.64; 95% CI 1.57–1.72), and tracheostomy on HD7 (1.53; 95%CI 1.18–1.99). MP was associated with the development of moderate-severe ARDS on HD1 (2.07; 95% CI 1.56–2.78) and HD3 (1.76; 95% CI 1.41–2.22).ConclusionsExposure to high MP during the first week of MV is associated with poor clinical outcomes in ABI, independent of P/F ratio and neurological severity. Potential benefits of optimizing ventilator settings to limit MP warrant further investigation.

PaCO2 trajectories in mechanically ventilated patients with COVID-19: A population-based cohort study.

To identify PaCO2 trajectories and assess their associations with mortality in critically ill patients with coronavirus disease 2019 (COVID-19) during the first and second waves of the pandemic in Denmark. A population-based cohort study with retrospective data collection. All COVID-19 patients were treated in eight intensive care units (ICUs) in the Capital Region of Copenhagen, Denmark, between March 1, 2020 and March 31, 2021. Data from the electronic health records were extracted, and latent class analyses were computed based on up to the first 3 weeks of mechanical ventilation to depict trajectories of PaCO2 levels. Multivariable Cox regression analyses were used to calculate adjusted hazard ratios (aHRs) for Simplified Acute Physiology Score 3, sex and age with 95% confidence intervals (CIs) for death according to PaCO2 trajectories. In latent class trajectory models, including 25,318 PaCO2 measurements from 244 patients, three PaCO2 latent class trajectories were identified: a low isocapnic (Class I; n=130), a high isocapnic (Class II; n=80), as well as a progressively hypercapnic (Class III; n=34) trajectory. Mortality was higher in Class II [aHR: 2.16 {1.26-3.68}] and Class III [aHR: 2.97 {1.63-5.40}]) compared to Class I (reference). Latent class analysis of arterial blood gases in mechanically ventilated COVID-19 patients identified distinct PaCO2 trajectories, which were independently associated with mortality.

Mapping peripheral and abdominal sarcopenia acquired in the acute phase of COVID-19 during 7 days of mechanical ventilation

Our aim was to map acquired peripheral and abdominal sarcopenia in mechanically ventilated adults with COVID-19 through ultrasound measurements. On Days 1, 3, 5 and 7 after admission to critical care, the muscle thickness and cross-sectional area of the quadriceps, rectus femoris, vastus intermedius, tibialis anterior, medial and lateral gastrocnemius, deltoid, biceps brachii, rectus abdominis, internal and external oblique, and transversus abdominis were measured using bedside ultrasound. A total of 5460 ultrasound images were analyzed from 30 patients (age: 59.8 ± 15.6 years; 70% men). Muscle thickness loss was found in the bilateral anterior tibial and medial gastrocnemius muscles (range 11.5–14.6%) between Days 1 and 3; in the bilateral quadriceps, rectus femoris, lateral gastrocnemius, deltoid, and biceps brachii (range 16.3–39.1%) between Days 1 and 5; in the internal oblique abdominal (25.9%) between Days 1 and 5; and in the rectus and transversus abdominis (29%) between Days 1 and 7. The cross-sectional area was reduced in the bilateral tibialis anterior and left biceps brachii (range 24.6–25.6%) between Days 1 and 5 and in the bilateral rectus femoris and right biceps brachii (range 22.9–27.7%) between Days 1 and 7. These findings indicate that the peripheral and abdominal muscle loss is progressive during the first week of mechanical ventilation and is significantly higher in the lower limbs, left quadriceps and right rectus femoris muscles in critically ill patients with COVID-19.

Ventilatory Parameters Measured After One Week of Mechanical Ventilation and Survival in COVID-19-Related ARDS.

Ventilatory parameters measured soon after initiation of mechanical ventilation have limited ability to predict outcome of COVID-19-related ARDS. We hypothesized that ventilatory parameters measured after one week of mechanical ventilation might differ between survivors and non-survivors. One hundred twenty-seven subjects with COVID-related ARDS had gas exchange and lung mechanics assessed on the day of intubation and one week later. The main parameters of interest were PaO2 /FIO2 , ventilatory ratio (VR), respiratory system compliance (CRS), and a composite score that was calculated as (PaO2 /FIO2 /100) × CRS/VR. The primary outcome was death in the ICU. Of the 127 subjects, 42 (33%) died in the ICU and 85 (67%) were successfully extubated. On the day of intubation, PaO2 /FIO2 , CRS, and composite score of survivors and non-survivors were similar, but survivors had a lower VR. At one week, as compared to survivors, non-survivors had a significantly higher VR (2.04 ± 0.76 vs 1.60 ± 0.43, P < .001), lower CRS (27.4 ± 6.4 mL/cm H2O vs 32.4 ± 9.3 mL/cm H2O, P = .002), and lower composite score (20.6 ± 11.9 vs 34.5 ± 18.6, P < .001), with no statistically significant difference in PaO2 /FIO2 (137 ± 49 vs 155 ± 48, P = .08). In subjects with COVID ARDS, parameters that reflect dead space (VR), lung mechanics (CRS), and a combined score that included PaO2 /FIO2 , VR, and CRS differed between survivors and non-survivors after one week of mechanical ventilation but with considerable overlap of values between survivors and non-survivors.

Respiratory Physiology of COVID-19 and Influenza Associated Acute Respiratory Distress Syndrome.

Background: There is ongoing debate whether lung physiology of COVID-19-associated acute respiratory distress syndrome (ARDS) differs from ARDS of other origin. Objective: The aim of this study was to analyze and compare how critically ill patients with COVID-19 and Influenza A or B were ventilated in our tertiary care center with or without extracorporeal membrane oxygenation (ECMO). We ask if acute lung failure due to COVID-19 requires different intensive care management compared to conventional ARDS. Methods: 25 patients with COVID-19-associated ARDS were matched to a cohort of 25 Influenza patients treated in our center from 2011 to 2021. Subgroup analysis addressed whether patients on ECMO received different mechanical ventilation than patients without extracorporeal support. Results: Compared to Influenza-associated ARDS, COVID-19 patients had higher ventilatory system compliance (40.7 mL/mbar [31.8-46.7 mL/mbar] vs. 31.4 mL/mbar [13.7-42.8 mL/mbar], p = 0.198), higher ventilatory ratio (1.57 [1.31-1.84] vs. 0.91 [0.44-1.38], p = 0.006) and higher minute ventilation at the time of intubation (mean minute ventilation 10.7 L/min [7.2-12.2 L/min] for COVID-19 vs. 6.0 L/min [2.5-10.1 L/min] for Influenza, p = 0.013). There were no measurable differences in P/F ratio, positive end-expiratory pressure (PEEP) and driving pressures (ΔP). Respiratory system compliance deteriorated considerably in COVID-19 patients on ECMO during 2 weeks of mechanical ventilation (Crs, mean decrease over 2 weeks -23.87 mL/mbar ± 32.94 mL/mbar, p = 0.037) but not in ventilated Influenza patients on ECMO and less so in ventilated COVID-19 patients without ECMO. For COVID-19 patients, low driving pressures on ECMO were strongly correlated to a decline in compliance after 2 weeks (Pearson's R 0.80, p = 0.058). Overall mortality was insignificantly lower for COVID-19 patients compared to Influenza patients (40% vs. 48%, p = 0.31). Outcome was insignificantly worse for patients requiring veno-venous ECMO in both groups (50% mortality for COVID-19 on ECMO vs. 27% without ECMO, p = 0.30/56% vs. 34% mortality for Influenza A/B with and without ECMO, p = 0.31). Conclusion: The pathophysiology of early COVID-19-associated ARDS differs from Influenza-associated acute lung failure by sustained respiratory mechanics during the early phase of ventilation. We question whether intubated COVID-19 patients on ECMO benefit from extremely low driving pressures, as this appears to accelerate derecruitment and consecutive loss of ventilatory system compliance.

The possible predictive value of muscle ultrasound in the diagnosis of ICUAW in long-term critically ill patients.

Intensive Care Unit acquired weakness (ICUAW) occurs commonly. Muscular ultrasonography allows visualization and classification of muscle characteristics. The aims of this study were to evaluate peripheral and respiratory muscles, their changes during long-term ICU stays, and the possible diagnostic predictive value of ICUAW as compared to the Medical Research Council strength score (MRC-SS). 50 mechanically ventilated patients were enrolled. Within 48 h after ICU admission (T1), patients underwent muscular ultrasound (rectus femoris cross sectional area (RFCSA), pennation angle, diaphragm, and parasternal intercostal). All the same measures were repeated at days 3 (T3) and 7 (T7). Muscle strength assessment was performed using the MRC-SS. No significant differences were found regarding age, sex, weight, height, or BMI values, in those who developed ICUAW according to MRC-SS. The RF pennation angle, however, significantly changed between T7-T1 in patients who developed ICUAW and was. Found to be the best predictor of ICUAW. Quadriceps and respiratory muscles were altered within the first week of mechanical ventilation. The loss of pennation angle offers high diagnostic accuracy for ICUAW, allowing for an earlier diagnosis before patients became able to perform volitional tests.

Gelsolin Attenuates Neonatal Hyperoxia-Induced Inflammatory Responses to Rhinovirus Infection and Preserves Alveolarization.

Prematurity and bronchopulmonary dysplasia (BPD) increase the risk of asthma later in life. Supplemental oxygen therapy is a risk factor for chronic respiratory symptoms in infants with BPD. Hyperoxia induces cell injury and release of damage-associated molecular patterns (DAMPs). Cytoskeletal filamentous actin (F-actin) is a DAMP which binds Clec9a, a C-type lectin selectively expressed on CD103+ dendritic cells (DCs). Co-stimulation of Clec9a and TLR3 induces maximal proinflammatory responses. We have shown that neonatal hyperoxia (a model of BPD) increases lung IL-12+Clec9a+CD103+ DCs, pro-inflammatory responses and airway hyperreactivity following rhinovirus (RV) infection. CD103+ DCs and Clec9a are required for these responses. Hyperoxia increases F-actin levels in bronchoalveolar lavage fluid (BALF). We hypothesized that the F-actin severing protein gelsolin attenuates neonatal hyperoxia-induced Clec9a+CD103+ DC-dependent pro-inflammatory responses to RV and preserves alveolarization. We exposed neonatal mice to hyperoxia and treated them with gelsolin intranasally. Subsequently we inoculated the mice with RV intranasally. Alternatively, we inoculated normoxic neonatal mice with BALF from hyperoxia-exposed mice (hyperoxic BALF), RV and gelsolin. We analyzed lung gene expression two days after RV infection. For in vitro studies, lung CD11c+ cells were isolated from C57BL/6J or Clec9agfp-/- mice and incubated with hyperoxic BALF and RV. Cells were analyzed by flow cytometry. In neonatal mice, gelsolin blocked hyperoxia-induced Il12p40, TNF-α and IFN-γ mRNA and protein expression in response to RV infection. Similar effects were observed when gelsolin was co-administered with hyperoxic BALF and RV. Gelsolin decreased F-actin levels in hyperoxic BALF in vitro and inhibited hyperoxia-induced D103lo DC expansion and inflammation in vivo. Gelsolin also attenuated hyperoxia-induced hypoalveolarization. Further, incubation of lung CD11c+ cells from WT and Clec9agfp-/- mice with hyperoxic BALF and RV, showed Clec9a is required for maximal hyperoxic BALF and RV induced IL-12 expression in CD103+ DCs. Finally, in tracheal aspirates from mechanically ventilated human preterm infants the F-actin to gelsolin ratio positively correlates with FiO2, and gelsolin levels decrease during the first two weeks of mechanical ventilation. Collectively, our findings demonstrate a promising role for gelsolin, administered by inhalation into the airway to treat RV-induced exacerbations of BPD and prevent chronic lung disease.

Prognostic factors and outcomes in COVID-19 patients requiring prolonged mechanical ventilation: a retrospective cohort study.

Background:Mechanical ventilation (MV) in coronavirus disease 2019 (COVID-19) patients is associated with high mortality and extensive resource utilization. The aim of this study was to investigate prognostic factors and outcomes associated with prolonged mechanical ventilation (PMV) in COVID-19 patients.Methods:This was a retrospective cohort study of COVID-19 patients requiring invasive MV who were hospitalized between 1 March 2020 and 30 June 2021 in the intensive care units (ICUs) of three referral hospitals belonging to a single health system. Data were extracted from electronic health records. PMV was defined as > 17 days of MV.Results:Of 355 patients studied, 86 (24%) required PMV. PMV patients had lower PaO2/FiO2 ratio, higher PCO2, and higher plateau and driving pressures during the first 2 weeks of MV than their short MV (SMV; ⩽ 17 days) counterparts. PMV patients received more proning, neuromuscular blockade, and tracheostomy, had longer ICU and hospital length of stay (LOS), and required discharge to an inpatient rehabilitation facility more frequently (all p < 0.001). Overall 30-day mortality was 43.9%, with no statistically significant difference between PMV and SMV groups. In PMV patients, smoking, Charlson comorbidity index > 6, and week 2 PaO2/FiO2 ratio < 150 and plateau pressure ⩾ 30 were positively associated with 30-day mortality. In a multivariate model, results were directionally consistent with the univariate analysis but did not reach statistical significance.Conclusion:PMV is commonly required in COVID-19 patients with respiratory failure. Despite the higher need for critical care interventions and LOS, more than half of the PMV cohort survived to hospital discharge. Higher PaO2/FiO2 ratio, lower plateau pressure, and fewer comorbidities appear to be associated with survival in this group.

Prolonged progressive hypermetabolism during COVID-19 hospitalization undetected by common predictive energy equations.

Background & aimsIndirect calorimetry (IC) is the gold-standard for determining measured resting energy expenditure (mREE) in critical illness. When IC is not available, predicted resting energy expenditure (pREE) equations are commonly utilized, which often inaccurately predict metabolic demands leading to over- or under-feeding. This study aims to longitudinally assess mREE via IC in critically ill patients with SARS-CoV-2 (COVID-19) infection throughout the entirety of, often prolonged, intensive care unit (ICU) stays and compare mREE to commonly utilized pREE equations.MethodsThis single-center prospective cohort study of 38 mechanically ventilated COVID-19 patients from April 1, 2020 to February 1, 2021. The Q-NRG® Metabolic Monitor was used to obtain IC data. The Harris-Benedict (HB), Mifflin St-Jeor (MSJ), Penn State University (PSU), and weight-based equations from the American Society of Parenteral and Enteral Nutrition – Society of Critical Care Medicine (ASPEN-SCCM) Clinical Guidelines were utilized to assess the accuracy of common pREE equations and their ability to predict hypo/hypermetabolism in COVID-19 ICU patients.ResultsThe IC measures collected revealed a relatively normometabolic or minimally hypermetabolic mREE at 21.3 kcal/kg/d or 110% of predicted by the HB equation over the first week of mechanical ventilation (MV). This progressed to significant and uniquely prolonged hypermetabolism over successive weeks to 28.1 kcal/kg/d or 143% of HB predicted by MV week 3, with hypermetabolism persisting to MV week 7. Obese individuals displayed a more truncated response with significantly lower mREE versus non-obese patients in MV week 1 (19.5 ± 1.0 kcal/kg/d vs 25.1 ± 1.8 kcal/kg/d, respectively; p < 0.01), with little change in weeks 2–3 (19.5 ± 1.5 kcal/kg/d vs 28.0 ± 2.0 kcal/kg/d; p < 0.01). Both ASPEN-SCCM upper range and PSU pREE equations provided close approximations of mREE yet, like all pREE equations, occasionally over- and under-predicted energy needs and typically did not predict late hypermetabolism.ConclusionsStudy results show a truly unique metabolic response in COVID-19 ICU patients, characterized by significant and prolonged, progressive hypermetabolism peaking at 3 weeks’ post-intubation, persisting for up to 7 weeks in ICU. This pattern was more clearly demonstrated in non-obese versus obese patients. This response is unique and distinct from any previously described model of ICU stress response in its prolonged hypermetabolic nature. This data reaffirms the need for routine, longitudinal IC measures to provide accurate energy targets in COVID-19 ICU patients. The PSU and ASPEN-SCCM equations appear to yield the most reasonable estimation to IC-derived mREE in COVID-19 ICU patients, yet still often over-/under-predict energy needs. These findings provide a practical guide for caloric prescription in COVID-19 ICU patients in the absence of IC.

Expiratory Muscles, Neglected No More.

Expiratory Muscles, Neglected No More.

Changes in Respiratory Muscle Thickness during Mechanical Ventilation: Focus on Expiratory Muscles.

The lateral abdominal wall muscles are recruited with active expiration, as may occur with high breathing effort, inspiratory muscle weakness, or pulmonary hyperinflation. The effects of critical illness and mechanical ventilation on these muscles are unknown. This study aimed to assess the reproducibility of expiratory muscle (i.e., lateral abdominal wall muscles and rectus abdominis muscle) ultrasound and the impact of tidal volume on expiratory muscle thickness, to evaluate changes in expiratory muscle thickness during mechanical ventilation, and to compare this to changes in diaphragm thickness. Two raters assessed the interrater and intrarater reproducibility of expiratory muscle ultrasound (n = 30) and the effect of delivered tidal volume on expiratory muscle thickness (n = 10). Changes in the thickness of the expiratory muscles and the diaphragm were assessed in 77 patients with at least two serial ultrasound measurements in the first week of mechanical ventilation. The reproducibility of the measurements was excellent (interrater intraclass correlation coefficient: 0.994 [95% CI, 0.987 to 0.997]; intrarater intraclass correlation coefficient: 0.992 [95% CI, 0.957 to 0.998]). Expiratory muscle thickness decreased by 3.0 ± 1.7% (mean ± SD) with tidal volumes of 481 ± 64 ml (P < 0.001). The thickness of the expiratory muscles remained stable in 51 of 77 (66%), decreased in 17 of 77 (22%), and increased in 9 of 77 (12%) patients. Reduced thickness resulted from loss of muscular tissue, whereas increased thickness mainly resulted from increased interparietal fasciae thickness. Changes in thickness of the expiratory muscles were not associated with changes in the thickness of the diaphragm (R2 = 0.013; P = 0.332). Thickness measurement of the expiratory muscles by ultrasound has excellent reproducibility. Changes in the thickness of the expiratory muscles occurred in 34% of patients and were unrelated to changes in diaphragm thickness. Increased expiratory muscle thickness resulted from increased thickness of the fasciae.

Prescription practice and clinical utility of chest radiographs in a pediatric intensive care unit: a prospective observational study

BackgroundChest radiograph (CXR) prescribing pattern and practice vary widely among pediatric intensive care units (PICU). ‘On demand’ approach is increasingly recommended as against daily ‘routine’ CXRs; however, the real-world practice is largely unknown.MethodsThis was a prospective observational study performed in children younger than 12 years admitted to PICU of a tertiary care teaching hospital in India. Data were collected on all consecutive CXRs performed between December 2016 and April 2017. The primary outcome was to assess the factors that were associated with higher chest radiograph prescriptions in PICU. Secondary outcomes were to study the indications, association with mechanical ventilation, image quality and avoidable radiation exposure.ResultsOf 303 children admitted during the study period, 159 underwent a total of 524 CXRs in PICU. Median (IQR) age of the study cohort was 2 (0.6–5) years. More than two thirds [n = 115, 72.3%] were mechanically ventilated. Most CXRs (n = 449, 85.7%) were performed on mechanically ventilated patients, amounting to a median (IQR) of 3 (2–5) radiographs per ventilated patient. With increasing duration of ventilation, the number of CXRs proportionately increased in the first two weeks of mechanical ventilation. In non-ventilated children, about two thirds (68%) underwent only one CXR. Majority of the prescriptions were on demand (n = 461, 88%). Most common indications were peri-procedure prescriptions (37%) followed by evaluation for respiratory disease status (24%). About 40% CXRs resulted in interventions; adjustment in ventilator settings (13.5%) was the most frequent intervention. In 26% (n = 138) of radiographs, image quality required improvement. One or more additional body part exposure other than chest and upper abdomen were noted 336 (64%) images. Children with > 3 CXR had higher PRISM III score, more often mechanically ventilated, had higher number of indwelling devices [mean (SD) 2.6 (1.2) vs. 1.7 (1.0)] and stayed longer in PICU [median (IQR) 11(7.5–18.5) vs. 6 (3–9)].ConclusionOn demand prescription was the prevalent practice in our PICU. Most non-ventilated children underwent only one CXR while duration of PICU stay and the number of devices determined the number of CXRs in mechanically ventilated children. Quality improvement strategies should concentrate on the process of acquisition of images and limiting the radiation exposure to unwanted body parts.

Predictors of Mortality and Effect of Drug Therapies in Mechanically Ventilated Patients With Coronavirus Disease 2019: A Multicenter Cohort Study.

We conducted a multicenter cohort study to determine the effect of drug therapies on survival in mechanically ventilated patients with coronavirus disease 2019. All consecutive adult patients admitted to ICU for coronavirus disease 2019 from March 1, 2020, to April 25, 2020, and under invasive mechanical ventilation for more than 24 hours were included. Out of 2,003 patients hospitalized for coronavirus disease 2019, 361 were admitted to ICU, 257 were ventilated for more than 24 hours, and 247 were included in the study. Simple and multiple time-dependent Cox regression models were used to assess the effects of factors on survival. Methylprednisolone administration during the first week of mechanical ventilation was associated with a decrease in mortality rate from 48% to 34% (p = 0.01). Mortality was significantly associated with older age, higher creatinine, lower lymphocyte count, and mean arterial pressure lower than 70 mm Hg on the day of admission.

Diaphragmatic atrophy and dysfunction in critically ill mechanically ventilated children.

The extent of diaphragmatic atrophy and dysfunction in critically ill children from developing countries is not established. To estimate changes in ultrasound measurements of diaphragmatic thickness over the first week of mechanical ventilation. To assess magnitude and risk factors of diaphragmatic atrophy. In an observational cohort study, children aged 1-18 years, requiring mechanical ventilation were included. Ultrasound measurements of diaphragmatic thickness at end-expiration (DTe) and end-inspiration (DTi), and diaphragmatic thickening fraction (DTF) were performed daily during the first week of admission, and pre- and post-extubation. Diaphragmatic atrophy (%) and atrophy rate (rate of decline in DTe, % per day) were calculated. Of 55 children (74.6% boys) enrolled, 20 (36.4%) died. Of 35 children with planned extubation, 5 (14.3%) required reintubation. Baseline median (interquartile range [IQR]) DTe, DTi, and DTF were 1.27 mm (1, 1.6), 1.76 mm (1.35, 2.10),and 33.75% (26.90, 44.60), respectively. There was a significant reduction in DTe over the first week of mechanical ventilation (p < .001), median (IQR) diaphragmatic atrophy and atrophy rate of 9.91% (5.26, 17.35) and 2.01% (1.08, 3.04)per day, respectively. Diaphragmatic atrophy rate was lower in pressure targeted ventilation (n = 44; 1.79%[1.03, 2.87])than volume targeted ventilation (n = 11; 3.10% [1.31, 5.49]), p = .038. There was no difference in diaphragmatic parameters (atrophy rate, and peri-extubation DTe and DTF) in extubation success versus failure. The diaphragm undergoes progressive atrophy during the first week of mechanical ventilation in critically ill children. Future studies should evaluate ventilation strategies to reduce the diaphragmatic atrophy.

Prognostic risk factors for respiratory failure after esophagectomy.

BackgroundEsophagectomy is a high-risk surgical procedure with significant postoperative morbidity and mortality. Respiratory failure is one of the most common complications after esophageal cancer surgery. The purpose of this study was to explore risk factors that affect the recovery of respiratory failure in this kind of patients.MethodsTotally 2,360 patients underwent esophagectomies with cervical anastomosis or intrathoracic anastomosis in our center from January 2012 to December 2017. Among them, 130 patients with respiratory failure requiring mechanical ventilation were included in the study. The Spearman’s rank correlation test and Mann-Whitney U test were performed to identify the influential factors for the duration of mechanical ventilation.ResultsMost patients (81.5%) in this study recovered in the first two weeks of mechanical ventilation, the average duration of mechanical ventilation was 10.1 days. Statistical analysis indicated that lung function test parameters such as FEV1/FVC ratio and RV/TLC ratio could have significant influence on the duration of mechanical ventilation. The abnormally increased FEV1/FVC ratio and RV/TLC ratio could obviously prolong the ventilation duration. Old age, thrombocytopenia, the elevated creatinine, C-reactive protein (CRP) and lactate could also significantly lengthen the duration of mechanical ventilation.ConclusionsAbnormally increased FEV1/FVC ratio and RV/TLC ratio as well as old age, thrombocytopenia, elevated creatinine, CRP and blood lactate were found to be risk factors for the recovery of patients with respiratory failure after esophagectomies.

Effect of acute kidney injury on weaning from mechanical ventilation in chronic obstructive pulmonary diseases patients with respiratory failure

BackgroundAcute kidney injury (AKI) worsens the outcome in mechanically ventilated patients. The occurrence of AKI may have an effect on weaning from mechanical ventilation (MV). The purpose of this work is to study the effect of AKI on weaning from MV for chronic obstructive pulmonary disease (COPD) patients with respiratory failure (RF). The study included 100 mechanically ventilated COPD patients with RF. Patients were classified into group 1, mechanically ventilated COPD patients with type 2 RF who developed AKI, and group 2, mechanically ventilated COPD patients with type 2 RF, who did not develop AKI.ResultsThe age of the studied group ranged between 46 and 80 years, and serum creatinine on admission was within normal. There is a significant difference in a serum creatinine level after 2 days and after 1 week of MV in an intensive care unit (ICU) among AKI cases. There is a significant difference in weaning success between AKI and non-AKI patients with much higher weaning success in non-AKI group. Also, there is a significant reduction in glomerular filtration rate (GFR) in AKI patients after 48 h of admission.ConclusionsAKI is frequent in COPD patients within 48 h of ICU admission and MV increases the risk of AKI in COPD patients.

A View from the Frontline: Palliative and Ethical Considerations of the COVID-19 Pandemic.

A View from the Frontline: Palliative and Ethical Considerations of the COVID-19 Pandemic.

Surrogates and Physician Preferences regarding the Continuation of Mechanical Ventilation among Critically Ill Adults.

Rationale: For an incapacitated patient who is difficult to liberate from mechanical ventilation, surrogates and physicians will decide to continue life support if they believe doing so is consistent with the patient's prognosis and values. Little is known about the factors that surrogates and physicians prioritize during this decision-making process, in part because there is not a validated method to assess their preferences.Objectives: To evaluate trends in surrogate and physician preferences for continuing mechanical ventilation.Methods: One hundred surrogates and respective physicians of patients requiring mechanical ventilation for at least 7 days were prospectively enrolled at an academic, tertiary care medical center. During the second and third week of mechanical ventilation, participant preferences for continuing mechanical ventilation were assessed in two ways, the first emphasizing patient survival and the second emphasizing patient comfort as the primary goal.Results: During the patient's second week of mechanical ventilation, surrogates agreed more strongly than did physicians that mechanical ventilation should be continued to maximize the chance for patient survival (73% vs. 63%, respectively, P = 0.02 for difference). In contrast, at this same point in time, surrogates and physicians agreed similarly that mechanical ventilation should be discontinued to maximize patient comfort (37% vs. 38%, respectively, P = 0.34 for difference). Both surrogates and physicians agreed less strongly during week 3 than they did during week 2 that mechanical ventilation should be continued with a goal of maximizing patient survival, with preferences to limit the use of mechanical ventilation for patients with the poorest prognoses according to physiological variables. In contrast, only physicians agreed more strongly during week 3 than they did during week 2 that mechanical ventilation should be discontinued to maximize patient comfort.Conclusions: Level of surrogate and physician agreement that mechanical ventilation should be continued to maximize the chance for patient survival reflected their preferences more accurately than level of surrogate and physician agreement that mechanical ventilation should be discontinued to maximize patient comfort. Over time, surrogates and physicians were less likely to agree that mechanical ventilation should be continued, particularly when patients had poor prognoses.

Multicenter Experience with Neurally Adjusted Ventilatory Assist in Infants with Severe Bronchopulmonary Dysplasia.

The aim of this study is to determine patterns of neurally adjusted ventilatory assist (NAVA) use in ventilator-dependent preterm infants with evolving or established severe bronchopulmonary dysplasia (sBPD) among centers of the BPD Collaborative, including indications for its initiation, discontinuation, and outcomes. Retrospective review of infants with developing or established sBPD who were placed on NAVA after ≥4 weeks of mechanical ventilation and were ≥ 30 weeks of postmenstrual age (PMA). Among the 13 sites of the BPD collaborative, only four centers (31%) used NAVA in the management of infants with evolving or established BPD. A total of 112 patients met inclusion criteria from these four centers. PMA, weight at the start of NAVA and median number of days on NAVA, were different among the four centers. The impact of NAVA therapy was assessed as being successful in 67% of infants, as defined by the ability to achieve respiratory stability at a lower level of ventilator support, including extubation to noninvasive positive pressure ventilation or support with a home ventilator. In total 87% (range: 78-100%) of patients survived until discharge. We conclude that NAVA can be used safely and effectively in selective infants with sBPD. Indications and current strategies for the application of NAVA in infants with evolving or established BPD, however, are highly variable between centers. Although this pilot study suggests that NAVA may be successfully used for the management of infants with BPD, sufficient experience and well-designed clinical studies are needed to establish standards of care for defining the role of NAVA in the care of infants with sBPD.