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Example of lung CT scan of patients with high (upper panel) or low (lower panel) potential of lung recruitment
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Background
Acute respiratory distress syndrome (ARDS) is characterized by a noncardiogenic pulmonary edema with bilateral chest X-ray opacities and reduction in lung compliance, and the hallmark of the syndrome is hypoxemia refractory to oxygen therapy. Severe hypoxemia (PaO2/FiO2 < 100 mmHg), which defines severe ARDS, can be found in 20–30 % of t...
Context in source publication
Context 1
... role in the framework of the lung-protective strategy, avoiding intratidal opening and closing and de- creasing lung inhomogeneities [4,[16][17][18]. Owing to the different amounts of lung edema, the total lung recruit- ability (estimated by lung computed tomography (CT) scan) was found to range from 0 to 70 % of the total lung weight [19] (Fig. 1). Presently, although the lung CT scan requires the transport of patients outside the ICU and the use of X-ray radiation, it remains the gold standard to compute lung recruitability [20,21]. The use of a visual scale to estimate lung recruitment and the ap- plication of a low-dose protocol for CT scan acquisition have shown promising ...
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Background
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Background:
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Citations
... The present study indicated that laryngeal mask airway placement during general anesthesia could reduce the complications of general anesthesia, such as hypoxemia and postoperative cough; in addition, one-time implantation of the laryngeal mask airway exhibited a high success rate. Compared with endotracheal intubation, a laryngeal mask airway during general anesthesia may reduce hypoxemia following general anesthesia (34). Hypoxia can be induced by ventilation and/or ventilation dysfunction due to various causes, such as central nervous system disorders and bronchial and pulmonary diseases (29,30). ...
At present, there is no relevant expert consensus indicating which ventilation device is more efficient for general anesthesia. The present literature review and meta-analysis compared the effects of the laryngeal mask airway and endotracheal intubation on airway complications during general anesthesia. The keywords ‘laryngeal mask airway’, ‘endotracheal tube’, ‘tracheal tube’, ‘children’, ‘pediatric’, ‘anesthesia’, ‘randomized controlled trials’ (RCTs) and ‘randomized’ were used to perform the literature search in PubMed. Quality assessment was performed by two reviewers according to domains defined by the Cochrane Collaboration tool. Data extraction, risk of bias assessment and quality of evidence assessment were performed with the Cochrane tool. A total of 16 RCTs were included. The results indicated that the effects of the laryngeal mask airway group on heart rate variability [mean difference=-13.76; 95% CI, -18.19-(-9.33); P<0.00001], the incidence of hypoxemia [odds ratio (OR)=0.52; 95% CI, 0.28-0.97; P=0.04] and the incidence of postoperative cough (OR=0.22; 95% CI, 0.12-0.40; P<0.0001) were significantly lower than those of the endotracheal intubation group. The success rate of one-time implantation in the laryngeal mask airway group was significantly higher than that noted in the endotracheal intubation group (OR=0.20; 95% CI, 0.07-0.59; P=0.003). However, no significant differences were noted between the two groups in bronchospasm, sore throat, mucosal injury, nausea and vomiting and reflux aspiration. In conclusion, the results indicated that laryngeal mask airway application can reduce complications during general anesthesia compared with endotracheal intubation.
... Multiple serious injuries are often observed with chest injuries and cause impaired pulmonary ventilation or pulmonary exchange, leading to severe injuries complicated by respiratory failure and increased patient morbidity and mortality. 8 Previous studies have reported that bedside ultrasound allows investigators to make rapid diagnostic results, improving diagnostic accuracy and reducing the time for diagnosis confirmation. 9 In this study, we compared the diagnostic performance of different examination methods in patients with severe multiple injuries complicated by respiratory failure. ...
Background
To investigate the early application of pulmonary ultrasonography and arterial blood gas analysis in critical patients with severe multiple injuries exacerbated by respiratory failure.
Patients and Methods
The retrospective selection was performed on 81 patients admitted to our critical care unit between January 2020 and January 2021 with severe multiple injuries rendered worse by respiratory failure. Based on the different examination procedures, the patients were categorised into three groups (n=27): group A; diagnosed with pulmonary ultrasonography, group B; diagnosed with arterial blood gas; and group C; diagnosed with both pulmonary ultrasonography and arterial blood gas analyses. Patients were subsequently divided into a survival group (n = 65) and a death group (n = 16). On an annual basis, patients’ prognoses were examined in relation to the predictive value of pulmonary ultrasound.
Results
Initial diagnosis, diagnosis, and initial correct treatment times were significantly shorter in groups B and C than group A (P<0.05). In contrast, initial diagnosis time, diagnosis time, and initial correct treatment times were potentially shorter in group C than in group B (P<0.05). Compared to groups B and C, group A had a considerably lower diagnosis rate for the examination methods (P<0.05). The right diaphragm displacement and left diaphragm displacement in the survival group were potentially higher than the LUS score (P < 0.05). In contrast, the survival group’s lung ultrasound score (LUS) was considerably lower than the death group’s. Statistical analysis showed that the predictive values of right diaphragm displacement, left diaphragm displacement, and mean diaphragm displacement were significant compared with the LUS score. The findings of the receiver operating characteristic curve demonstrated that the right, left, and average diaphragm displacements had high predictive values.
Conclusion
In the early evaluation of patients with severe multiple injuries complicated by respiratory failure, pulmonary ultrasonography combined with arterial blood gas analysis is crucial for the rapid diagnosis and prognosis prediction of patients.
... 1,2 IMV carries relatively higher mortality and complication rates compared to non-invasive respiratory support, however, delaying IMV causes excess mortality as well. [23][24][25] Therefore, timing is of utmost importance and several studies investigated predictors for intubation in COVID-19 patients with ARF. 14,26,27 Awake PP has been utilized more during the pandemic, however, predictors for intubation in patients who received PP are scarce. ...
COVID-19 pneumonia causes acute respiratory distress syndrome (ARDS). Prone positioning (PP) is beneficial to pulmonary physiology and improves oxygenation in patients with ARDS. We aimed to investigate the effect of the PP on oxygenation, respiratory rate (RR) and ROX index in non-intubated patients with COVID-19 associated respiratory failure and to determine whether ROX index predicts intubation. Awake critically-ill patients with confirmed diagnosis of COVID-19 who underwent PP were enrolled in the retrospective, single-center study. Oxygenation parameters were recorded 1 h before PP, during PP and 1 h after return to supine position (after PP). Intubation was defined as the endpoint. Seventy-one patients with a median age of 64 [55-73] years were enrolled in the study. PaO2/FiO2 and SpO2/FiO2 improved during PP, this improvement did not persist after PP. RR improved during and after PP in both intubated and non-intubated patients (for all P < .001). ROX index improved only in non-intubated patients (P < .001) but not in intubated patients (P = .07). Area under the curve (AUC) of ROX index for intubation before PP, during PP and after PP were 0.74 [0.61-0.88] (P = .002), 0.76 [0.62-0.91] (P = .001), and 0.76 [0.64-0.89] (P = .001), respectively. ROX index >6.83 before PP had a negative predictive value (NPV) of 0.85; ROX index >8.28 during PP had a NPV of 0.88 and ROX index >7.48 after PP had a NPV of 0.85. In logistic regression adjusted for APACHE II score, ROX index ≤6.83 before PP had an odds ratio (OR) 4.47 [1.39-14.38], ROX index ≤8.28 during PP had an OR 7.96 [2.29-27.64] and ROX index ≤7.48 had an OR 3.98 [1.25-12.61] for prediction of intubation. In conclusion, awake PP improves oxygenation and decreases RR. ROX index improved only in non- intubated patients and a higher ROX index predicts lower risk of progressing to mechanical ventilation with intubation.
... Acute respiratory distress syndrome (ARDS) ranks the top one of total number of deaths in acute respiratory failure worldwide [1][2][3][4][5][6] , especially in those of moderate to severe ARDS, with an estimated in-hospital death up to 25% to 77% 1-10 , particularly in those of the elderly ARDS who always have the poorest prognostic outcomes 7 . Of distinctive importance is that for those moderate-severe patients, even utilization of currently therapeutic standard method, such as extracorporeal membrane oxygenation, the in-hospital motility rate remains unacceptably high 8,[10][11][12][13] , suggesting that standard conventional therapy for ARDS is an unmet need 12,14 . Accordingly, to find a new modality with safety and efficacy for those of moderate-severe ARDS patients is urgent and utmost important. ...
This study tested whether human umbilical cord-derived mesenchymal stem cells (HUCDMSCs) treatment effectively protected the rat lung against acute respiratory distress syndrome (ARDS) injury, and benefits of early and dose-dependent treatment. Rat pulmonary epithelial cell line L2 (PECL2) were categorized into G1 (PECL2), G2 (PECL2 + healthy rat lung-derived extraction/50 mg/ml co-cultured for 24 h), G3 (PECL2 + ARDS rat lung-derived extraction/50 mg/ml co-cultured for 24 h), and G4 (condition as G3 + HUCDMSCs/1 × 105/co-cultured for 24 h). The result showed that the protein expressions of inflammatory (HMGB-1/TLR-2/TLR-4/MAL/TRAM/MyD88/TRIF/TRAF6/IkB/NF-κB/IL-1β/TNF-α), oxidative-stress/mitochondrial-damaged (NOX-1/NOX-2/ASK1/p-MKK4/p-MKK7/JNKs/JUN/cytosolic-cytochrome-C/cyclophilin-D/DRP1), and cell-apoptotic/fibrotic (cleaved-caspase 3/cleaved-PARP/TGF-β/p-Smad3) biomarkers were significantly increased in G3 than in G1/G2 and were significantly reversed in G4 (all P < 0.001), but they were similar between G1/G2. Adult male rats (n = 42) were equally categorized into group 1 (normal control), group 2 (ARDS only), group 3 [ARDS + HUCDMSCs/1.2 × 106 cells intravenous administration at 3 h after 48 h ARDS induction (i.e., early treatment)], group 4 [ARDS + HUCDMSCs/1.2 × 106 cells intravenous administration at 24 h after 48 h ARDS induction (late treatment)], and group 5 [ARDS + HUCDMSCs/1.2 × 106 cells intravenous administration at 3 h/24 h after-48 h ARDS induction (dose-dependent treatment)]. By day 5 after ARDS induction, the SaO2%/immune regulatory T cells were highest in group 1, lowest in group 2, significantly lower in group 4 than in groups 3/5, and significantly lower in group 3 than in group 5, whereas the circulatory/bronchioalveolar lavage fluid inflammatory cells (CD11b-c+/LyG6+/MPO+)/circulatory immune cells (CD3-C4+/CD3-CD8+)/lung-leakage-albumin level/lung injury score/lung protein expressions of inflammatory (HMGB-1/TLR-2/TLR-4/MAL/TRAM/MyD88/TRIF/TRAF6/IκB-β/p-NF-κB/IL-1β/TNF-α)/fibrotic (p-SMad3/TGF-β), apoptosis (mitochondrial-Bax/cleaved-caspase-3)/oxidative-cell-stress (NOX-1/NOX-2/ASK1/p-MKK4/p-MKK7/p-JNKs/p-cJUN)/mitochondrial damaged (cyclophilin-D/DRP1/cytosolic-cytochrome-C) biomarkers displayed an opposite pattern of SaO2% among the groups (all P < 0.0001). Early administration was superior to and two-dose counterpart was even more superior to late HUCDMSCs treatment for protecting the lung against ARDS injury.
... The results in this study suggest that it is possible to establish response-predicting scores. These findings support the early use of other rescue strategies, including more extensive prone positioning or extracorporeal membrane oxygenation in patients with ARDS of any etiology, (24) to manage refractory hypoxemia. ...
Objective
To identify risk factors for nonresponse to prone positioning in mechanically ventilated patients with COVID-19-associated severe acute respiratory distress syndrome and refractory hypoxemia in a tertiary care hospital in Colombia.
Methods
Observational study based on a retrospective cohort of mechanically ventilated patients with severe acute respiratory distress syndrome due to SARS-CoV-2 who underwent prone positioning due to refractory hypoxemia. The study considered an improvement ≥ 20% in the PaO2/FiO2 ratio after the first cycle of 16 hours in the prone position to be a ‘response’. Nonresponding patients were considered cases, and responding patients were controls. We controlled for clinical, laboratory, and radiological variables.
Results
A total of 724 patients were included (58.67 ± 12.37 years, 67.7% males). Of those, 21.9% were nonresponders. Mortality was 54.1% for nonresponders and 31.3% for responders (p < 0.001). Variables associated with nonresponse were time from the start of mechanical ventilation to pronation (OR 1.23; 95%CI 1.10 - 1.41); preintubation PaO2/FiO2 ratio (OR 0.62; 95%CI 0.40 - 0.96); preprone PaO2/FiO2 ratio (OR 1.88. 95%CI 1.22 - 2.94); and radiologic multilobe consolidation (OR 2.12; 95%CI 1.33 - 3.33) or mixed pattern (OR 1.72; 95%CI 1.07 - 2.85) compared with a ground-glass pattern.
Conclusion
This study identified factors associated with nonresponse to prone positioning in patients with refractory hypoxemia and acute respiratory distress syndrome due to SARS-CoV-2 receiving mechanical ventilation. Recognizing such factors helps identify candidates for other rescue strategies, including more extensive prone positioning or extracorporeal membrane oxygenation. Further studies are needed to assess the consistency of these findings in populations with acute respiratory distress syndrome of other etiologies.
... It has been reported [53] that for patients with ARDS who are still considered severe cases even after ECMO treatment, improvement as observed by lung imaging is hardly noticeable, and the effect of lung recruitment is poor. Combined with PPV treatment, the physiological function of the lungs can be maximized, making up for ECMO's inability to improve gas redistribution. ...
Approximately 2% of the global population lives above 1500 m, where low atmospheric pressure, decreased oxygen levels, harsh cold and dry conditions, strong radiation, and the effects of climate change present significant health challenges. Residents of these high-altitude areas display physiological adaptions, including smaller body size, enlarged ribs, improved oxygen delivery in hypoxic conditions, and adjustments in oxygen utilization and metabolism. Both acute and chronic hypoxia prevalent in such regions can trigger various diseases by stimulating hypoxia-inducible factors, boosting inflammatory responses, and impairing mitochondrial function.Acute Respiratory Distress Syndrome (ARDS) - a critical respiratory condition associated with high morbidity and mortality - occurs more frequently among the health risks in these environments. Hypoxia is a critical predisposing and aggravating factor for high-altitude ARDS. Despite similarities with its low-altitude counterpart, ARDS in high-altitude areas displays unique pathophysiology and clinical manifestations due to the specific environmental conditions.This review aims to shed light on how high-altitude environments influence the diagnosis and treatment of ARDS, providing a comprehensive understanding of the distinct challenges inherent to these regions.
... Hypoxemia is usually defined by a SpO 2 range of 88-92%. [ 19 ] In a prospective ARDS cohort, refractory hypoxemia (defined by a PaO 2 of less than 60 mmHg with an FiO 2 of 1) occurred in 21% of patients. [ 20 ] In view of the risk associated with several interventions aimed at increasing oxygenation (e.g. ...
Determining oxygenation targets in acute respiratory distress syndrome (ARDS) remains a challenge. Although oxygenation targets have been used since ARDS was first described, they have not been investigated in detail. However, recent retrospective and prospective trials have evaluated the optimal oxygenation threshold in patients admitted to the general intensive care unit. In view of the lack of prospective data, clinicians continue to rely on data from the few available trials to identify the optimal oxygenation strategy. Assessment of the cost-benefit ratio of the fraction of inspired oxygen (FiO2) to the partial pressure of oxygen in the arterial blood (PaO2) is an additional challenge. A high FiO2 has been found to be responsible for respiratory failure and deaths in numerous animal models. Low and high PaO2 values have also been demonstrated to be potential risk factors in experimental and clinical situations. The findings from this literature review suggest that PaO2 values ranging between 80 mmHg and 90 mmHg are acceptable in patients with ARDS. The costs of rescue maneuvers needed to reach these targets have been discussed. Several recent papers have highlighted the risk of disagreement between arterial oxygen saturation (SaO2) and peripheral oxygen saturation (SpO2) values. In order to avoid discrepancies and hidden hypoxemia, SpO2 readings need to be compared with those of SaO2. Higher SpO2 values may be needed to achieve the recommended PaO2 and SaO2 values.
... Hypoxemia is caused by a range of common conditions-including childhood pneumonia, newborn conditions (4,5), and obstetric emergencies (6,7). The body of the sufferer will experience severe detrimental consequences from hypoxemia on the cells that carry out crucial biological functions (8). The atmospheric air with a 21% O 2 concentration and when its percentage is below 19.5% by volume and/or highly elevated CO 2 level in air is called an oxygen-deficient condition (9). ...
Medical-grade oxygen is the basic need for all medical complications, especially in respiratory-based discomforts. There was a drastic increase in the demand for medical-grade oxygen during the current pandemic. The non-availability of medical-grade oxygen led to several complications, including death. The oxygen concentrator was only the last hope for the patient during COVID-19 pandemic around the globe. The demands also are everlasting during other microbial respiratory infections. The yield of oxygen using conventional molecular zeolites in the traditional oxygen concentrator process is less than the yield noticed when its nano-form is used. Nanotechnology has enlightened hope for the efficient production of oxygen by such oxygen concentrators. Here in the current review work, the authors have highlighted the basic structural features of oxygen concentrators along with the current working principle. Besides, it has been tried to bridge the gap between conventional oxygen concentrators and advanced ones by using nanotechnology. Nanoparticles being usually within 100 nm in size have a high surface area to volume ratio, which makes them suitable adsorbents for oxygen. Here authors have suggested the use of nano zeolite in place of molecular zeolites in the oxygen concentrator for efficient delivery of oxygen by the oxygen concentrators.
... While it was reduced to <10 cm H2O in five studies, and below 14 cm H2O in all reporting studies, TV remained slightly above 4 mL/kg in the majority. [20][21][22][23][24][25] ECCO2R is rightly referred to as a low-flow ECMO. [26] ECCO2R was originally developed to reduce the intensity of mechanical ventilation in patients with acute hypercarbic respiratory failure. ...
Protective lung ventilation is the mainstay ventilation strategy for patients on extracorporeal membrane oxygenation (ECMO), as prolonged mechanical ventilation increases morbidity and mortality; the technicalities of ventilation with ECMO have evolved in the last decade. ECMO on the other end of the spectrum is a complete or total extracorporeal support, which supplies complete physiological blood gas exchanges, normally performed by the native lungs and thus is capable of delivering oxygen (O2) and removing CO equal to the metabolic needs of the patient, it requires higher flows, is more complex, and uses bigger cannulas, higher dose of heparin and higher blood volume for priming. This review describes in detail carbon dioxide removal on ECMO.
... Proning posture during invasive mechanical ventilation is used for ARDS 2 patients and is almost the standard procedure. Prone posture improved oxygenation in severe ARDS, and 8,9 considerable mortality benefits were demonstrated. On the basis of previous studies done on ARDS patients due to different etiologies, it was speculated that proning of awake patients would improve patients' oxygenation and prevent or delay more invasive procedures like Introduction Apart from routine guidelines practices of Covid-19 patients management, we applied 2 interventions like PP and NIV and observed 120 patients for 4 weeks duration for primary outcome of SpO2 improvement, and secondary outcomes like, mortality, mean ICU/HDU hospital stay among those who survived, and rate of Intubation among those who deteriorated during the course of proning and NIV intervention. ...
Results: The study included 68% males and 32% female patients with median age of 60 years (IQR-18-80). After initiation of the standard PP, 80% of 120 subjects, the SpO2 values improved from median 70% (IQR 60-80) to median 93% (IQR 89-97) and P/F ratio from 100 (IQR 77-123) to 150 (IQR 123-177) within median 6 days (IQR 2-8) of admission. PP was adopted for median 12 hours/24 hours (IQR 4-16), and 90% were applied NIV for 12 hours/24 hours (IQR 6-18) with median 12 days (IQR 7-28). Mortality rate was 27% and 18% were intubated for invasive ventilators. Total hospital stay was 16 days (median-IQR 10-28). Background: Before Covid-19 Pandemic, few studies speculated that early initiation of proning position in combination with NIV increases the probability of improved oxygenation in patients with ARDS. Methodology: We studied 120 Covid-19 positive patients admitted in ICU/HDU, F.J Institute of Chest Diseases, Quetta-Pakistan. They were subjected to PP combined NIV and observed for 4 weeks duration for primary outcome of improvement in SpO2 and PaO2/FiO2 (P/F) ratio. Data for secondary outcomes like intubation rate, median stay in hospital and mortality rate were also noted. Conclusions: Early awake self-proning combined with NIV application demonstrated improved oxygen saturation (SpO2 & P/F ratio) and avoided intubation in our Covid19 related ARDS/Pneumonia Patients. Objective: We conducted an observational study to look for the beneficial effect of proning position combined with NIV in awake, non-intubated ICU/HDU patients presented with Covid19 associated ARDS and Pneumonia.
