Project description:The efficacy of non-invasive ventilation (NIV) in acute respiratory failure secondary to SARS-CoV-2 infection remains controversial. Current literature mainly examined efficacy, safety and potential predictors of NIV failure provided out of the intensive care unit (ICU). On the contrary, the outcomes of ICU patients, intubated after NIV failure, remain to be explored. The aims of the present study are: (1) investigating in-hospital mortality in coronavirus disease 2019 (COVID-19) ICU patients receiving endotracheal intubation after NIV failure and (2) assessing whether the length of NIV application affects patient survival. This observational multicenter study included all consecutive COVID-19 adult patients, admitted into the twenty-five ICUs of the COVID-19 VENETO ICU network (February-April 2020), who underwent endotracheal intubation after NIV failure. Among the 704 patients admitted to ICU during the study period, 280 (40%) presented the inclusion criteria and were enrolled. The median age was 69 [60-76] years; 219 patients (78%) were male. In-hospital mortality was 43%. Only the length of NIV application before ICU admission (OR 2.03 (95% CI 1.06-4.98), p = 0.03) and age (OR 1.18 (95% CI 1.04-1.33), p < 0.01) were identified as independent risk factors of in-hospital mortality; whilst the length of NIV after ICU admission did not affect patient outcome. In-hospital mortality of ICU patients intubated after NIV failure was 43%. Days on NIV before ICU admission and age were assessed to be potential risk factors of greater in-hospital mortality.
Project description:PurposeLimited mechanical ventilators (MV) during the Coronavirus disease (COVID-19) pandemic have led to the use of non-invasive ventilation (NIV) in hypoxemic patients, which has not been studied well. We aimed to assess the association of NIV versus MV with mortality and morbidity during respiratory intervention among hypoxemic patients admitted with COVID-19.MethodsWe performed a retrospective multi-center cohort study across 5 hospitals during March-April 2020. Outcomes included mortality, severe COVID-19-related symptoms, time to discharge, and final oxygen saturation (SpO2) at the conclusion of the respiratory intervention. Multivariable regression of outcomes was conducted in all hypoxemic participants, 4 subgroups, and propensity-matched analysis.ResultsOf 2381 participants with laboratory-confirmed SARS-CoV-2, 688 were included in the study who were hypoxemic upon initiation of respiratory intervention. During the study period, 299 participants died (43%), 163 were admitted to the ICU (24%), and 121 experienced severe COVID-19-related symptoms (18%). Participants on MV had increased mortality than those on NIV (128/154 [83%] versus 171/534 [32%], OR = 30, 95% CI 16-60) with a mean survival of 6 versus 15 days, respectively. The MV group experienced more severe COVID-19-related symptoms [55/154 (36%) versus 66/534 (12%), OR = 4.3, 95% CI 2.7-6.8], longer time to discharge (mean 17 versus 7.1 days), and lower final SpO2 (92 versus 94%). Across all subgroups and propensity-matched analysis, MV was associated with a greater OR of death than NIV.ConclusionsNIV was associated with lower respiratory intervention mortality and morbidity than MV. However, findings may be liable to unmeasured confounding and further study from randomized controlled trials is needed to definitively determine the role of NIV in hypoxemic patients with COVID-19.
Project description:RNASeq technology is applied to study the gene expression affected by ventilation in diaphragm and intercostal. Groups under short-term (6 hours to 4 days) or long-term (4.5 to 9 days) ventilation are included besides the healthy control group.
Project description:It is recognized that diaphragm muscle plasticity occurs with mechanical overloads, yet less is known about synergistic parasternal intercostal muscle fiber remodeling. We conducted overload training with intrinsic transient tracheal occlusion (ITTO) exercises in conscious animals. We hypothesized that ITTO would yield significant fiber hypertrophy and myogenic activation that would parallel diaphragm fiber remodeling. Sprague-Dawley rats underwent placement of a tracheal cuff and were randomly assigned to receive daily 10 min sessions of conscious ITTO or observation (sham) over 2 wk. After training, fiber morphology, myosin heavy chain (MHC) isoform composition, cross-sectional area, proportion of Pax7-positive nuclei, and presence of embryonic MHC (eMHC) were quantified. Type IIx/b fibers were 20% larger after ITTO training than with sham training (ITTO: 4,431 +/– 676 μm2, sham: 3,689 +/– 400 μm2, p < 0.05), and type I fibers were more prevalent after ITTO (p < 0.01). Expression of Pax7 was increased in ITTO parasternals and diaphragm (p < 0.05). In contrast, the proportion of eMHC-positive fibers was increased only in ITTO parasternals (1.2% [3.4%–0.6%], sham: 0% [0.6%–0%], p < 0.05). Although diaphragm and parasternal type II fibers hypertrophy to a similar degree, myogenic remodeling appears to differ between the two muscles.
Project description:The use of non-invasive ventilation in patients with community-acquired pneumonia is controversial since this is associated with high rates of treatment failure, compared with other causes of severe acute respiratory failure. The populations of patients with community-acquired pneumonia who have demonstrated better response to non-invasive ventilation are those with previous cardiac or respiratory disease, particularly chronic obstructive pulmonary disease. By contrast, the use of non-invasive ventilation in patients with community-acquired pneumonia without these pre-existing diseases should be very cautious and under strict monitoring conditions, since there are increasing evidences that the unnecessary delay in intubation of those patients who fail treatment with non-invasive ventilation is associated with lower survival. Pulmonary complications of immunosuppressed patients are associated with high rates of intubation and mortality. The use of non-invasive ventilation in these patients may decrease the need for intubation and improve the poor outcome associated with these complications. Continuous positive airway pressure has been used to treat acute respiratory failure in several conditions characterised by alveolar collapse. While this is extremely useful in patients with acute cardiogenic pulmonary oedema, the efficacy in pneumonia seems limited to immunosuppressed patients with pulmonary complications. Conversely, there are no sufficient evidences on the efficacy of continuous positive airway pressure in immunocompetent patients with pneumonia and severe acute respiratory failure.
Project description:AIMS: To make non-invasive measurements of right to left (R-L) shunt and reduced ventilation/perfusion ratio (V(A)/Q) in neonates with pulmonary failure and to examine sequential changes in these variables after treatment. METHODS: Twelve neonates with pulmonary failure were studied. They ranged in gestational age from 24 to 37 (median 27) weeks and were 1-39 (median 4) days old. Shunt and reduced V(A)/Q were derived from their effects on the relation between inspired oxygen pressure (PIO(2)) and arterial oxygen saturation measured with a pulse oximeter (SpO(2)). Pairs of PIO(2) v. SpO(2) data points were obtained by varying PIO(2) in a stepwise fashion. A computer algorithm based on a model of pulmonary gas exchange fitted a curve to these data. With PIO(2) on the abscissa, an increase in shunt produced a downward movement of the curve, whereas reducing V(A)/Q to < 0.8 shifted the curve to the right. The right shift gives a variable that is inversely related to V(A)/Q, the PIO(2) - PO(2) difference, where PO(2) is mixed capillary oxygen pressure. RESULTS: Ten of the 12 infants on the first study day had large shunts (range 5.9-31.0%, median 19.9%, normal < 8%) and large PIO(2) - PO(2) differences (range 9.7-64.4 kPa, median 19.8 kPa, normal < 7 kPa) equivalent to a median V(A)/Q of 0.2 (normal median V(A)/Q = 0.8). Sequential improvement in shunt and V(A)/Q were shown in most infants after treatment. Sudden large changes in these variables were shown in two infants. CONCLUSION: This simple non-invasive method distinguishes between shunt and reduced V(A)/Q in neonates with pulmonary failure.
Project description:Acute respiratory failure (RF) is a life-threatening syndrome. This study investigated the application of two major clinical strategies, non-invasive mechanical ventilation (NIV) and invasive mechanical ventilation (IMV), in the first episode of acute RF. Data from the longitudinal health insurance database, which included 1,000,000 insured citizens, were used. The NIV group consisted of 1201 patients and the IMV group consisted of 16,072 patients. Chi-square test and t test were applied to determine the differences in categorical and continuous variables. Further analysis was performed by using univariate and multivariable logistic regression and Poisson regression. There was a significant increase of 733% in the number of NIV users from 2000 to 2012. NIV use was frequently observed in old-age persons (aOR 3.99, 95% CI 3.06-5.21 for those aged???80 years), women (aOR 1.33, 95% CI 1.18-1.50), patients admitted to a high-level hospital (aOR 1.95, 95% CI 1.63-2.34 for those admitted to a medical center), and patients with a higher Charlson comorbidity index (CCI, aOR 1.38-1.66 for those CCI???2). In addition, patients with chronic pulmonary disease, cancer, and congestive heart failure were predominant in NIV users and were significantly associated with NIV use. Overall, the use of NIV has markedly increased over the past few years. Persons of advanced age, women, patients admitted to a high-level hospital, and patients with multiple comorbidities were associated with more frequent NIV use. Chronic pulmonary disease, cancer, and congestive heart failure were most important comorbidities for NIV use.
Project description:Record keeping for patients on non-invasive ventilation (NIV) at St. Georges Hospital is poor. The initial NIV prescription is often not recorded, and changes to the NIV prescription or the rationale for the changes (ABG results) are also poorly documented. This leads to confusion for nurses/doctors as to what the correct settings are, meaning patients could receive ineffective ventilation. The use of NIV is also poorly recorded by nursing staff meaning that doctors are unsure if the prescribed NIV is being achieved. This can lead to treatment being escalated unnecessarily in the event of treatment failure. Non-invasive ventilation (NIV) is the provision of ventilatory support in the form of positive pressure via the patient's upper airway using a mask or similar device. NIV is indicated for treatment of acute hypercapnic respiratory failure, of which there are many causes, though COPD is the indication in up to 70% of cases.[1] British Thoracic Society (BTS) guidelines for NIV suggest that the rationale for commencing a patient on NIV and the proposed settings should be clearly documented.[2] Clinicians cannot effectively tailor changes to the patients NIV settings if this information is not clearly recorded, which could lead to increased time requiring NIV or NIV failure. Three main areas were considered important to measure for this project. The initial prescription of the NIV, changes to the NIV settings, and nursing documentation surrounding NIV. A baseline measurement of NIV documentation for two weeks found NIV documentation to globally very poor. NIV was formally prescribed 29% of the time, full detail of intended settings were documented 57% of the time, the decision to commence NIV was discussed with the respiratory consultant/SpR just 29% of the time and on no occasion was a decision regarding escalation of treatment recorded. Eighteen changes were made to the NIV settings. These were formally prescribed 22% of the time and detail of the intended settings was recorded 44% of the time. Nursing documentation included detail on the length of NIV use just 21% of the time, and comments on the NIV use were left just 33% of the time. The intervention was a unified four page NIV prescription chart. Page 1: An area for the NIV to be initially prescribed with reminder questions for important considerations. Page 2: An area for changes to be made to the NIV settings. Page 3: An area for the most up to date NIV/respiratory plan to be documented. Page 4: Nursing documentation, with prompts for the time NIV was put on/off and for comments. The chart was printed at St Georges print services and paid for by the respiratory ward. A further two weeks of monitoring followed after implementation of the new chart. Improvements were seen in all areas of documentation surrounding NIV. The NIV was formally prescribed 86% of the time compared to 29% pre-intervention. The NIV settings were stated 100% of the time in the initial prescription. An escalation decision was recorded 71% of the time. Changes to the NIV settings improved to 92%. Nursing documentation improved greatly. The length of the NIV use was recorded for 91% of NIV days compared to 21% previously (p<0.001), and comments on the use of NIV improved from from 33% to 98% (p<0.001). Cases where the documentation remained poor were in those patients for whom the new chart had not been used. The implementation of a unified NIV prescription chart to be kept in the bedside notes on the respiratory ward greatly improved documentation surrounding NIV. Further work must be done to ensure that the chart is used 100% of the time. This will include adjusting the chart to reduce the workload to use it, rolling the chart out on the acute medical ward, and submitting the chart to the trust board for its acceptance as an official trust chart.
Project description:ObjectiveGuidelines from different regions on the use of non-invasive ventilation in COVID-19 have generally been inconsistent. The aim of this systematic review was to appraise the quality and availability of guidelines, and whether non-invasive ventilation in the early stages of the pandemic is of importance.Design and methodDatabases, including PubMed, Web of Science, and Cochrane Library, as well as websites of international organizations and gray literature, were searched up to June 23, 2020. The reference lists of eligible papers were also hand-searched.ResultsA total of 26 guidelines met the inclusion criteria. According to the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument, the guidelines' methodological quality was low. Among six domains, Rigour of Development and Editorial Independence were of the lowest quality. Given the lack of evidence from randomized clinical trials and the great variation between different regions, recommendations for non-invasive ventilation have generated considerable debate regarding the early stages of COVID-19.ConclusionsImproving the methodological quality of the guidelines should be a goal with regard to future pandemics. Additionally, better-designed randomized clinical trials are needed to resolve contradictions regarding the impact of non-invasive ventilation.Prospero registration numberCRD42020198410.