Although they take care of the vast majority of critically ill patients worldwide, intensive care units (ICUs) from low and middle income countries (LMICs) are confronted with huge challenges ...including medication, disposable and device shortage, in addition to human and material resource limitations. The following thoughts were driven by clinical observations during a cooperation mission in Sub-Saharan African ICUs. They aim at favoring a new approach in critical care research and innovation.
Zika Virus Associated with Meningoencephalitis Carteaux, Guillaume; Maquart, Marianne; Bedet, Alexandre ...
New England journal of medicine/The New England journal of medicine,
2016-Apr-21, Volume:
374, Issue:
16
Journal Article
Rationale
Increased right ventricle (RV) afterload during acute respiratory distress syndrome (ARDS) may induce acute cor pulmonale (ACP).
Objectives
To determine the prevalence and prognosis of ACP ...and build a clinical risk score for the early detection of ACP.
Methods
This was a prospective study in which 752 patients with moderate-to-severe ARDS receiving protective ventilation were assessed using transesophageal echocardiography in 11 intensive care units. The study cohort was randomly split in a derivation (
n
= 502) and a validation (
n
= 250) cohort.
Measurements and main results
ACP was defined as septal dyskinesia with a dilated RV end-diastolic RV/left ventricle (LV) area ratio >0.6 (≥1 for severe dilatation). ACP was found in 164 of the 752 patients (prevalence of 22 %; 95 % confidence interval 19–25 %). In the derivation cohort, the ACP risk score included four variables pneumonia as a cause of ARDS, driving pressure ≥18 cm H
2
O, arterial oxygen partial pressure to fractional inspired oxygen (PaO
2
/FiO
2
) ratio <150 mmHg, and arterial carbon dioxide partial pressure ≥48 mmHg. The ACP risk score had a reasonable discrimination and a good calibration. Hospital mortality did not differ between patients with or without ACP, but it was significantly higher in patients with severe ACP than in the other patients 31/54 (57 %) vs. 291/698 (42 %);
p
= 0.03. Independent risk factors for hospital mortality included severe ACP along with male gender, age, SAPS II, shock, PaO
2
/FiO
2
ratio, respiratory rate, and driving pressure, while prone position was protective.
Conclusions
We report a 22 % prevalence of ACP and a poor outcome of severe ACP. We propose a simple clinical risk score for early identification of ACP that could trigger specific therapeutic strategies to reduce RV afterload.
To the Editor, Continuous anterior chest compression (CACC) may have protective effects in patients with the Acute Respiratory Distress Syndrome (ARDS) by decreasing the anterior chest wall ...compliance, thus decreasing the anterior transpulmonary pressure and the resulting risk of overdistension 1 along with promoting redistribution of ventilation through the dependent regions. Regional effects of CACC were the followings: * A decrease in anterior (ventral) lung regions distension: the positive stress index pattern disappeared, the end-inspiratory transpulmonary pressure decreased and the regional lung compliance in the anterior half increased. * A recruitment of the posterior (dorsal) lung regions: the number of pixels showing positive ∆Z in the posterior half of EIT matrix increased by 10% and the regional lung compliance in the posterior half increased. * A homogenization of tidal ventilation: the ratio between ventilation distributions of the anterior and posterior halves went from 60%/40% to 50%/50%. Discussion The dramatic increase in respiratory system compliance during CACC in this ARDS patient may result from several combined mechanisms: 1-In the part of the lung already aerated but subject to intra-tidal overdistension, the noticeable decrease in the end expiratory lung volume resulted in a leftward shift of the pressure–volume curve below the upper inflexion point 3, 2-the concomitant recruitment in the posterior regions resulted in an increase in the number of aerated lung units 4.
Data on incidence of ventilator-associated pneumonia (VAP) and invasive pulmonary aspergillosis in patients with severe SARS-CoV-2 infection are limited.
We conducted a monocenter retrospective study ...comparing the incidence of VAP and invasive aspergillosis between patients with COVID-19-related acute respiratory distress syndrome (C-ARDS) and those with non-SARS-CoV-2 viral ARDS (NC-ARDS).
We assessed 90 C-ARDS and 82 NC-ARDS patients, who were mechanically ventilated for more than 48 h. At ICU admission, there were significantly fewer bacterial coinfections documented in C-ARDS than in NC-ARDS: 14 (16%) vs 38 (48%), p < 0.01. Conversely, significantly more patients developed at least one VAP episode in C-ARDS as compared with NC-ARDS: 58 (64%) vs. 36 (44%), p = 0.007. The probability of VAP was significantly higher in C-ARDS after adjusting on death and ventilator weaning sub-hazard ratio = 1.72 (1.14-2.52), p < 0.01. The incidence of multi-drug-resistant bacteria (MDR)-related VAP was significantly higher in C-ARDS than in NC-ARDS: 21 (23%) vs. 9 (11%), p = 0.03. Carbapenem was more used in C-ARDS than in NC-ARDS: 48 (53%), vs 21 (26%), p < 0.01. According to AspICU algorithm, there were fewer cases of putative aspergillosis in C-ARDS than in NC-ARDS 2 (2%) vs. 12 (15%), p = 0.003, but there was no difference in Aspergillus colonization.
In our experience, we evidenced a higher incidence of VAP and MDR-VAP in C-ARDS than in NC-ARDS and a lower risk for invasive aspergillosis in the former group.
Purpose
Hypercapnia is frequent during mechanical ventilation for acute respiratory distress syndrome (ARDS), but its effects on morbidity and mortality are still controversial. We conducted a ...systematic review and meta-analysis to explore clinical consequences of acute hypercapnia in adult patients ventilated for ARDS.
Methods
We searched Medline, Embase, and the Cochrane Library via the OVID platform for studies published from 1946 to 2021. “Permissive hypercapnia” defined hypercapnia in studies where the group with hypercapnia was ventilated with a protective ventilation (PV) strategy (lower
V
T
targeting 6 ml/kg predicted body weight) while the group without hypercapnia was managed with a non-protective ventilation (NPV); “imposed hypercapnia” defined hypercapnia in studies where hypercapnic and non-hypercapnic patients were managed with a similar ventilation strategy.
Results
Twenty-nine studies (10,101 patients) were included. Permissive hypercapnia, imposed hypercapnia under PV, and imposed hypercapnia under NPV were reported in 8, 21 and 1 study, respectively. Studies testing permissive hypercapnia reported lower mortality in hypercapnic patients receiving PV as compared to non-hypercapnic patients receiving NPV: OR = 0.26, 95% CI 0.07–0.89. By contrast, studies reporting imposed hypercapnia under PV reported increased mortality in hypercapnic patients receiving PV as compared to non-hypercapnic patients also receiving PV: OR = 1.54, 95% CI 1.15–2.07. There was a significant interaction between the mechanism of hypercapnia and the effect on mortality.
Conclusions
Clinical effects of hypercapnia are conflicting depending on its mechanism. Permissive hypercapnia was associated with improved mortality contrary to imposed hypercapnia under PV, suggesting a major role of PV strategy on the outcome.
A low or moderate expired tidal volume can be difficult to achieve during noninvasive ventilation for de novo acute hypoxemic respiratory failure (i.e., not due to exacerbation of chronic lung ...disease or cardiac failure). We assessed expired tidal volume and its association with noninvasive ventilation outcome.
Prospective observational study.
Twenty-four bed university medical ICU.
Consecutive patients receiving noninvasive ventilation for acute hypoxemic respiratory failure between August 2010 and February 2013.
Noninvasive ventilation was uniformly delivered using a simple algorithm targeting the expired tidal volume between 6 and 8 mL/kg of predicted body weight.
Expired tidal volume was averaged and respiratory and hemodynamic variables were systematically recorded at each noninvasive ventilation session.
Sixty-two patients were enrolled, including 47 meeting criteria for acute respiratory distress syndrome, and 32 failed noninvasive ventilation (51%). Pneumonia (n = 51, 82%) was the main etiology of acute hypoxemic respiratory failure. The median (interquartile range) expired tidal volume averaged over all noninvasive ventilation sessions (mean expired tidal volume) was 9.8 mL/kg predicted body weight (8.1-11.1 mL/kg predicted body weight). The mean expired tidal volume was significantly higher in patients who failed noninvasive ventilation as compared with those who succeeded (10.6 mL/kg predicted body weight 9.6-12.0 vs 8.5 mL/kg predicted body weight 7.6-10.2; p = 0.001), and expired tidal volume was independently associated with noninvasive ventilation failure in multivariate analysis. This effect was mainly driven by patients with PaO2/FIO2 up to 200 mm Hg. In these patients, the expired tidal volume above 9.5 mL/kg predicted body weight predicted noninvasive ventilation failure with a sensitivity of 82% and a specificity of 87%.
A low expired tidal volume is almost impossible to achieve in the majority of patients receiving noninvasive ventilation for de novo acute hypoxemic respiratory failure, and a high expired tidal volume is independently associated with noninvasive ventilation failure. In patients with moderate-to-severe hypoxemia, the expired tidal volume above 9.5 mL/kg predicted body weight accurately predicts noninvasive ventilation failure.
Purpose
Ultrasonography allows the direct observation of the diaphragm. Its thickness variation measured in the zone of apposition has been previously used to diagnose diaphragm paralysis. We ...assessed the feasibility and accuracy of this method to assess diaphragmatic function and its contribution to respiratory workload in critically ill patients under non-invasive ventilation.
Methods
This was a preliminary physiological study in the intensive care unit of a university hospital. Twelve patients requiring planned non-invasive ventilation after extubation were studied while spontaneously breathing and during non-invasive ventilation at three levels of pressure support (5, 10 and 15 cmH
2
O). Diaphragm thickness was measured in the zone of apposition during tidal ventilation and the thickening fraction (TF) was calculated as (thickness at inspiration − thickness at expiration)/thickness at expiration. Diaphragmatic pressure–time product per breath (PTP
di
) was measured from oesophageal and gastric pressure recordings.
Results
PTP
di
and TF both decreased as the level of pressure support increased. A significant correlation was found between PTP
di
and TF (ρ = 0.74,
p
< 0.001). The overall reproducibility of TF assessment was good but the coefficient of repeatability reached 18 % for inter-observer reproducibility.
Conclusions
Ultrasonographic assessment of the diaphragm TF is a non-invasive method that may prove useful in evaluating diaphragmatic function and its contribution to respiratory workload in intensive care unit patients.
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