Severe Hypoxemia Research Articles

High mortality and morbidity among vaccinated residents infected with the SARS-CoV-2 Omicron variant during an outbreak in a nursing home in Kyoto City, Japan

BackgroundOutbreaks of coronavirus disease 2019 (COVID-19) in long-term care facilities are associated with mortality, although vaccination have contributed to improvements. This study reports clinical impacts of a COVID-19 outbreak in a nursing home for elderly individuals in Kyoto City, Japan.MethodsWe performed epidemiologic and molecular investigations of the outbreak and characterized outcomes of the nursing home residents.ResultsDuring the outbreak period, a total of 31 residents (39.2%) and 26 staff members (49.1%) were infected with COVID-19. All residents and staff received two doses of a vaccine approximately 7 months prior. Ten residents with severe hypoxemia could not be transferred to a hospital due to a shortage of beds for COVID-19 patients. Within 90 days of the onset of the outbreak, 8 residents with COVID-19 (25.8%) died. A total of 48.4% of residents with COVID-19 developed 1 or more comorbidities. Viral genome analysis showed that the outbreak was caused by the Omicron BA.1.1.2 variant.ConclusionsDespite vaccination, high mortality and morbidity were observed in the COVID-19 outbreak due to the Omicron variant. Limiting medical care for residents with COVID-19 in facilities that experience ongoing outbreaks may be needed to reduce the risk of mortality among nursing home residents.

Extracorporeal membrane oxygenation circuits in parallel for refractory hypoxemia in patients with COVID-19

ObjectivesRefractory hypoxemia can occur in patients with acute respiratory distress syndrome from COVID-19 despite support with venovenous (VV) extracorporeal membrane oxygenation (ECMO). Parallel ECMO circuits can be used to increase physiologic support. We report our clinical experience using ECMO circuits in parallel for select patients with persistent severe hypoxemia despite the use of a single ECMO circuit. MethodsWe performed a retrospective cohort study of all patients with COVID–19-related acute respiratory distress syndrome who received VV-ECMO with an additional circuit in parallel at Vanderbilt University Medical Center between March 1, 2020, and March 1, 2022. We report demographic characteristics and clinical characteristics including ECMO settings, mechanical ventilator settings, use of adjunctive therapies, and arterial blood gas results after initial cannulation, before and after receipt of a second ECMO circuit in parallel, and before removal of the circuit in parallel, and outcomes. ResultsOf 84 patients with COVID-19 who received VV-ECMO during the study period, 22 patients (26.2%) received a circuit in parallel. The median duration of ECMO was 40.0 days (interquartile range, 31.6-53.1 days), of which 19.0 days (interquartile range, 13.0-33.0 days) were spent with a circuit in parallel. Of the 22 patients who received a circuit in parallel, 16 (72.7%) survived to hospital discharge and 6 (27.3%) died before discharge. ConclusionsIn select patients, the additional use of an ECMO circuit in parallel can increase ECMO blood flow and improve oxygenation while allowing for lung-protective mechanical ventilation and excellent outcomes.

Response to the first awake prone positioning relates with intubation rate in SARS-CoV-2 patients suffering from acute respiratory failure with moderate to severe hypoxaemia: a retrospective study.

Awake prone positioning (aPP) in non-intubated patients with severe SARS-CoV-2-related pneumonia improves oxygenation and reduces the intubation rate, but no early predictors for success or failure of the strategy have been described. The main objective of this study was to assess whether response to the first aPP in terms of PaO2/FiO2, alveolar-arterial gradient (Aa-O2), respiratory rate and PaCO2 could predict the need for intubation. As secondary objective, we assessed the effects of aPP on the same parameters for all the sessions considered together. Retrospective analysis of consecutive SARS-CoV-2 pneumonia patients suffering from acute respiratory failure with moderate to severe hypoxaemia for whom aPP was performed for at least 45 minutes based on the prescription of the clinician in charge according to predefined criteria. Respiratory rate, blood gases and oxygenation parameters (PaO2/FiO2 and Aa-O2), before and after the first aPP were compared between patients who were subsequently intubated or not. Effects of all the aPP sessions together were also analysed. One hundred and sixty-six patients were admitted for SARS-CoV-2 pneumonia during the study period. Among them, 50 received aPP lasting at least 45 minutes. Because 17 denied consent for data analysis and 2 were excluded because of a "do not intubate order", 31 patients (for a total of 116 aPP sessions without any severe adverse events reported) were included. Among them, 10 (32.3%) were intubated. Mean age ± standard deviation (SD) was 60 ± 12 years. At ICU admission, respiratory rate was 26 ± 7/minute, median PaO2/FiO2 94 (interquartile range [IQR] 74-116) mm Hg and median Aa-O2 412 (IQR 286-427) mm Hg (markedly increased). Baseline characteristics did not statistically differ between patients who subsequently needed intubation or not. During the first aPP, PaO2/FiO2 increased and Aa-O2 decreased. When comparing patients who later where intubated or not, we observed, in the non intubated group only, a clinically significant decrease in median Aa-O2, from 294 (280-414) to 204 (107-281) mm Hg, corresponding to a 40% (26-56%) reduction, and a PaO2/FiO2 increase, from 103 (84-116) to 162 (138-195), corresponding to an increase of 48% (11-93%). The p value is <0.005 for both. When all the aPP sessions (n = 80) were considered together, aPP was associated with a significant increase in PaO2/FiO2 from 112 (80-132) to 156 (86-183) mm Hg (p <0.001) and Aa-O2 decrease from 304 (244-418) to 224 (148-361) mm Hg (p = 0.001). Awake pronation in spontaneously breathing patients is feasible, and improves PaO2/FiO2 and Aa-O2. Response to the first session seems to be associated with lower intubation rate.

Prevalence and impact of early prone position on 30-day mortality in mechanically ventilated patients with COVID-19: a nationwide cohort study

BackgroundCOVID-19 ARDS shares features with non-COVID ARDS but also demonstrates distinct physiological differences. Despite a lack of strong evidence, prone positioning has been advocated as a key therapy for COVID-19 ARDS. The effects of prone position in critically ill patients with COVID-19 are not fully understood, nor is the optimal time of initiation defined. In this nationwide cohort study, we aimed to investigate the association between early initiation of prone position and mortality in mechanically ventilated COVID-19 patients with low oxygenation on ICU admission.MethodsUsing the Swedish Intensive Care Registry (SIR), all Swedish ICU patients ≥ 18 years of age with COVID-19 admitted between March 2020, and April 2021 were identified. A study-population of patients with PaO2/FiO2 ratio ≤ 20 kPa on ICU admission and receiving invasive mechanical ventilation within 24 h from ICU admission was generated. In this study-population, the association between early use of prone position (within 24 h from intubation) and 30-day mortality was estimated using univariate and multivariable logistic regression models.ResultsThe total study cohort included 6350 ICU patients with COVID-19, of whom 46.4% were treated with prone position ventilation. Overall, 30-day mortality was 24.3%. In the study-population of 1714 patients with lower admission oxygenation (PaO2/FiO2 ratio ≤ 20 kPa), the utilization of early prone increased from 8.5% in March 2020 to 48.1% in April 2021. The crude 30-day mortality was 27.2% compared to 30.2% in patients not receiving early prone positioning. We found no significant association between early use of prone positioning and survival.ConclusionsDuring the first three waves of the COVID-19 pandemic, almost half of the patients in Sweden were treated with prone position ventilation. We found no association between early use of prone positioning and survival in patients on mechanical ventilation with severe hypoxemia on ICU admission. To fully elucidate the effect and timing of prone position ventilation in critically ill patients with COVID-19 further studies are desirable.

Correlation and validity of imputed PaO2/FiO2 and SpO2/FiO2 in patients with invasive mechanical ventilation at 2600m above sea level.

To establish the correlation and validity between PaO2/FiO2 obtained on arterial gases versus noninvasive methods (linear, nonlinear, logarithmic imputation of PaO2/FiO2 and SpO2/FiO2) in patients under mechanical ventilation living at high altitude. Ambispective descriptive multicenter cohort study. Two intensive care units (ICU) from Colombia at 2600m a.s.l. Consecutive critically ill patients older than 18 years with at least 24h of mechanical ventilation were included from June 2016 to June 2019. None. Variables analyzed were demographic, physiological messures, laboratory findings, oxygenation index and clinical condition. Nonlinear, linear and logarithmic imputation formulas were used to calculate PaO2 from SpO2, and at the same time the SpO2/FiO2 by severe hypoxemia diagnosis. The intraclass correlation coefficient, area under the ROC curve, sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were calculated. The correlation between PaO2/FiO2 obtained from arterial gases, PaO2/FiO2 derived from one of the proposed methods (linear, non-linear, and logarithmic formula), and SpO2/FiO2 measured by the intraclass correlation coefficient was high (greater than 0.77, p<0.001). The different imputation methods and SpO2/FiO2 have a similar diagnostic performance in patients with severe hypoxemia (PaO2/FiO2 <150). PaO2/FiO2 linear imputation AUC ROC 0,84 (IC 0.81-0.87, p<0.001), PaO2/FiO2 logarithmic imputation AUC ROC 0.84 (IC 0.80-0.87, p<0.001), PaO2/FiO2 non-linear imputation AUC ROC 0.82 (IC 0.79-0.85, p<0.001), SpO2/FiO2 oximetry AUC ROC 0.84 (IC 0.81-0.87, p<0.001). At high altitude, the SaO2/FiO2 ratio and the imputed PaO2/FiO2 ratio have similar diagnostic performance in patients with severe hypoxemia ventilated by various pathological conditions.

Oxygen Delivery Devices in Hypoxemic Respiratory Failure

Oxygen therapy by appropriate oxygen delivery device (ODD) at different stages is an essential part of hypoxemic respiratory failure management. The choice of ODDs depends on the degree of hypoxemia, precision of delivery, patient comfort, risk of transmission of infection to Health Care Worker (HCW), and the cost. Management of hypoxemic respiratory failure depends on underlying etiology and pathophysiology of the disease process. Study from the current global pandemic of novel coronavirus disease 2019 (COVID-19) showed that the severity of hypoxemia is independently associated with in-hospital mortality and can be an important predictor risk of admission to intensive care unit. In this review, we will discuss the different ODDs, their indication for use along with the advantages and disadvantages.

The efficacy of high-frequency jet ventilation on intraoperative oxygen saturation compared to cross-field ventilation in patients undergoing carinal resection and reconstruction.

BackgroundCross-field ventilation is used as a conventional choice during carinal resection and anastomosis, but may interfere with surgical procedures. High-frequency jet ventilation (HFJV) allows for control of oxygenation in the open airways; nevertheless, there is a paucity of data to support its benefits versus cross-field ventilation. Herein, we aimed to investigate the efficacy of HFJV on intraoperative oxygen saturation compared with cross-field ventilation in patients undergoing carinal surgeries.MethodsWe conducted a retrospective analysis of 82 adults who underwent carinal resection and reconstruction (CRR) for benign or malignant diseases and received cross-field ventilation or HFJV at Shanghai Chest Hospital between January 2018 and September 2021. Patients were excluded when they had emergency surgeries or critical airway stenosis requiring extracorporeal life support, or limited resection without the need for cross-field ventilation or HFJV. Patients were classified into two groups based on the airway approach: cross-field ventilation group and HFJV group. The primary outcome was the area under the curve (AUC) of intraoperative hypoxemia defined as peripheral oxygen saturation (SpO2) below 90% lasting at least 1 minute. The secondary outcomes included cumulative time of SpO2 below 90%, AUC and cumulative time of severe intraoperative hypoxemia (defined as SpO2 below 80% lasting at least 1 minute), and AUC and cumulative time of suboptimal SpO2 (defined as SpO2 below 95% lasting at least 1 minute).ResultsThirty-two patients were included in the final analysis, with 22 patients in cross-field ventilation group and 10 patients in HFJV group. The two groups did not differ in the severity and duration of intraoperative hypoxemia (P=0.366). The median (IQR) AUC of SpO2 below 90% was 21.92 (4.28, 54.48) min in cross-field ventilation group and 28.93 (10.78, 199.89) min in HFJV group. The cumulative time of SpO2 <90% was 16.67 (4.46, 37.11) min in cross-field ventilation group and 19.32 (7.50, 121.24) min in HFJV group, without statistical difference between groups (P>0.05). Severe intraoperative hypoxemia did not occur in either group.ConclusionsThis retrospective case series demonstrates that HFJV can be adopted to maintain oxygenation in CRR, without the interruption of surgical procedure.

Hypoxemia Destabilizes The Neurovascular Unit During Extreme Apnea In Humans

To what extent voluntary asphyxia imposed by static apnea challenges the functional-structural limits of the neurovascular unit (NVU) in humans characterized by extremes of hypertension, hypoxemia and hypercapnia remains unclear. PURPOSE: To document the transcerebral exchange kinetics of NVU-specific proteins during extreme apnea and independent contributory influence of hypoxemia. METHODS: Ten world class breath-hold divers (6♂, 4♀) performed two maximal dry apneas preceded by normoxic normoventilation (NX: severe hypoxemia and hypercapnia) and hyperoxic hyperventilation (HX: absence of hypoxemia with exacerbating hypercapnia) with measurements obtained before and after apnea. Transcerebral exchange of NVU proteins (ELISA, Single Molecule Array) were calculated as the product of global cerebral blood flow (gCBF, duplex ultrasound) and radial arterial to internal jugular venous concentration gradients. RESULTS: Apnea duration increased from 5 m 6 s in NX to 15 m 59 s in HX (P = < 0.001) resulting in marked elevations in gCBF and venous S100B, glial fibrillary acidic protein, ubiquitin carboxy-terminal hydrolase-L1 and total tau (all P < 0.05 vs. baseline). This culminated in net cerebral output reflecting increased blood-brain barrier permeability and neuro-glio-vascular dysfunction that was more pronounced in NX due to more severe systemic and intracranial hypertension (P < 0.05 vs. HX). CONCLUSION: These findings identify the hemodynamic stress to which the apneic brain is exposed, highlighting the critical contribution of hypoxemia and not just hypercapnia to NVU destabilization.

The Characteristics of Sleep Apnea in Tibetans and Han Long-Term High Altitude Residents.

PurposeObstructive sleep apnea (OSA) is common both at low and high altitude. Since adaptations to high altitude and respiratory control may differ among Tibetans and Hans, we compared characteristics of sleep-disordered breathing in the two ethnic groups at high altitude.Materials and MethodsThis was a prospective observational study including 86 Tibetan and Han long-term (>5 years) high altitude residents with chief complaints of snoring and/or witnessed apnea underwent clinical evaluation and polysomnography at 3200 meters in Shangri-La, China.ResultsIn 42 Tibetans, 38 men, median (quartiles) age was 50.0 (41.0; 56.0)y, total apnea/hypopnea index (AHI) 53.9 (32.0; 77.5)/h, obstructive AHI 51.0 (28.0; 72.2)/h and central AHI 1.5 (0.2; 3.1)/h. In 44 Hans, 32 men, median (quartiles) age was 47.0 (43.5; 51.0)y, total AHI 22.2 (12.8; 39.2)/h, obstructive AHI 17.7 (12.0; 33.0)/h and central AHI 2.4 (0.5; 3.4)/h (p < 0.001 total and obstructive AHI vs Tibetans). In Tibetans, mean nocturnal oxygen saturation was lower [median 85.0 (83.0; 88.0)% vs 88.5 (87.0; 90.0)%] and obstructive apnea and hypopnea duration was longer [22.0 (19.6; 24.8) sec vs 18.3 (16.7; 20.6) sec] than in Hans (all p < 0.001). In regression analysis, Tibetan ethnicity, neck circumference and high-altitude living duration were the predictors of total AHI. We also found that with every 10/h increase in total AHI, there were an approximately 0.9 beat/min and 0.8 beat/min increase in mean heart rate during rapid eye movement (REM) and non-REM sleep and 1.9 mmHg and 2.0 mmHg increase in evening and morning systolic blood pressure.ConclusionOur data suggest that Tibetans presented more severe obstructive sleep apnea, hypoxemia and longer apnea duration compared to Hans at 3200 meters, which was correlated with higher heart rate and blood pressure suggesting a greater cardiovascular risk.

Correlation and validity of imputed PaO2/FiO2 and SpO2/FiO2 in patients with invasive mechanical ventilation at 2600 m above sea level

ObjectiveTo establish the correlation and validity between PaO2/FiO2 obtained on arterial gases versus noninvasive methods (linear, nonlinear, logarithmic imputation of PaO2/FiO2 and SpO2/FiO2) in patients under mechanical ventilation living at high altitude. DesignAmbispective descriptive multicenter cohort study. SettingTwo intensive care units (ICU) from Colombia at 2600m a.s.l. Patients or participantsConsecutive critically ill patients older than 18 years with at least 24h of mechanical ventilation were included from June 2016 to June 2019. InterventionsNone. VariablesVariables analyzed were demographic, physiological messures, laboratory findings, oxygenation index and clinical condition. Nonlinear, linear and logarithmic imputation formulas were used to calculate PaO2 from SpO2, and at the same time the SpO2/FiO2 by severe hypoxemia diagnosis. The intraclass correlation coefficient, area under the ROC curve, sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were calculated. ResultsThe correlation between PaO2/FiO2 obtained from arterial gases, PaO2/FiO2 derived from one of the proposed methods (linear, non-linear, and logarithmic formula), and SpO2/FiO2 measured by the intraclass correlation coefficient was high (greater than 0.77, p<0.001). The different imputation methods and SpO2/FiO2 have a similar diagnostic performance in patients with severe hypoxemia (PaO2/FiO2 <150). PaO2/FiO2 linear imputation AUC ROC 0,84 (IC 0.81–0.87, p<0.001), PaO2/FiO2 logarithmic imputation AUC ROC 0.84 (IC 0.80–0.87, p<0.001), PaO2/FiO2 non-linear imputation AUC ROC 0.82 (IC 0.79–0.85, p<0.001), SpO2/FiO2 oximetry AUC ROC 0.84 (IC 0.81–0.87, p<0.001). ConclusionsAt high altitude, the SaO2/FiO2 ratio and the imputed PaO2/FiO2 ratio have similar diagnostic performance in patients with severe hypoxemia ventilated by various pathological conditions.

Automatic oxygen control for reducing extremes of oxygen saturation: a randomised controlled trial

ObjectiveThe objective of this study was to evaluate the efficacy of the automatic oxygen control (A-Fio2) in reducing the percentage of time spent in severe hypoxaemia (Spo2 <80%) in preterm...

Effectiveness of Bubble Continuous Positive Airway Pressure (BCPAP) for Treatment of Children Aged 1–59 Months with Severe Pneumonia and Hypoxemia in Ethiopia: A Pragmatic Cluster Randomized Controlled Clinical Trial

Despite the beneficial effect of bubble continuous positive airway pressure (BCPAP) oxygen therapy for children with severe pneumonia under the supervision of physicians that has been shown in different studies, effectiveness trials in developing country settings where low-flow oxygen therapy is the standard of care are still needed. Thus, the aim of this study is to assess the effectiveness of bubble CPAP oxygen therapy compared to the WHO standard low-flow oxygen therapy among children hospitalized with severe pneumonia and hypoxemia in Ethiopia. This is a cluster randomized controlled trial where six district hospitals are randomized to BCPAP and six to standard WHO low-flow oxygen therapy. The total sample size is 620 per arm. Currently, recruitment of the patients is still ongoing where the management and follow-up of the enrolled patients are performed by general physicians and nurses under the supervision of pediatricians. The primary outcome is treatment failure and main secondary outcome is death. We anticipate to complete enrollment by September 2022 and data analysis followed by manuscript writing by December 2022. Findings will also be disseminated in December 2022. Our study will provide data on the effectiveness of BCPAP in treating childhood severe pneumonia and hypoxemia in a real-world setting.

A Comparison of Inhaled Epoprostenol in Patients With Acute Respiratory Distress Syndrome and COVID-19-Associated Acute Respiratory Distress Syndrome.

IntroductionAcute respiratory distress syndrome (ARDS) and coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (CARDS) are both characterized by non-cardiogenic pulmonary edema and severe hypoxemia that leads to a high percentage of patients suffering in-hospital mortality. Mechanistically, inhaled epoprostenol (iEPO) has shown a role in the treatment of ARDS and CARDS but little data are available directly comparing the two disease processes. Due to the lack of evidence of iEPO in ARDS and CARDS, the authors sought to compare the pulmonary effects of iEPO for mechanically ventilated patients with CARDS against a case match control of those with ARDS.MethodsA retrospective cohort of all patients receiving iEPO between January 1, 2020, and February 22, 2022, was reviewed. Patients with ARDS were case-matched in a 2:1 allocation ratio of CARDS to ARDS by the number of medical comorbidities and age +/- 5 years. Clinical data collected included patient demographics, laboratory values, ventilator settings, length of hospitalization, and 28-day mortality. Comparisons of the effectiveness of iEPO between ARDS and CARDS were conducted using the chi-squared statistic for categorical variables and the Mann-Whitney statistic for continuous variables.ResultsA total of 72 patients were included in the final analysis, with 24 having ARDS and 48 CARDS. The number of medical comorbidities was no different for patients with ARDS or CARDs (p = 0.18), though the frequency of patients diagnosed with coronary artery disease (p=0.007), congestive heart failure (p=0.003), chronic obstructive pulmonary disease (p=0.004), and pulmonary hypertension (p=0.004) did vary between the two groups. A moderate but non-significant difference in pre-iEPO partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ratio was noted between the groups (0.74 vs 0.65; p=0.33). Following iEPO treatment, patients with ARDS showed a greater PaO2/FiO2 ratio than those with CARDS (0.87 vs 0.70; p=0.02). CARDS patients who received iEPO had a longer length of stay as compared to those with ARDS (17.5 vs 12.5 days; p=0.01). However, no difference was noted in 28-day mortality between the two groups (14 vs 34; p=0.29).ConclusionIn this small sample from a single community hospital, a statistically significant improvement in the PaO2/FiO2 ratio was noted for both those with ARDS and CARDS. However, those with CARDS who were given iEPO had a longer length of stay without a significant difference in mortality as compared to those with traditional ARDS.

How to improve intubation in the intensive care unit. Update on knowledge and devices.

Tracheal intubation in the critically ill is associated with serious complications, mainly cardiovascular collapse and severe hypoxemia. In this narrative review, we present an update of interventions aiming to decrease these complications. MACOCHA is a simple score that helps to identify patients at risk of difficult intubation in the intensive care unit (ICU). Preoxygenation combining the use of inspiratory support and positive end-expiratory pressure should remain the standard method for preoxygenation of hypoxemic patients. Apneic oxygenation using high-flow nasal oxygen may be supplemented, to prevent further hypoxemia during tracheal intubation. Face mask ventilation after rapid sequence induction may also be used to prevent hypoxemia, in selected patients without high-risk of aspiration. Hemodynamic optimization and management are essential before, during and after the intubation procedure. All these elements can be integrated in a bundle. An airway management algorithm should be adopted in each ICU and adapted to the needs, situation and expertise of each operator. Videolaryngoscopes should be used by experienced operators.

COVID-19-Related ARDS: Key Mechanistic Features and Treatments.

Acute respiratory distress syndrome (ARDS) is a heterogeneous syndrome historically characterized by the presence of severe hypoxemia, high-permeability pulmonary edema manifesting as diffuse alveolar infiltrate on chest radiograph, and reduced compliance of the integrated respiratory system as a result of widespread compressive atelectasis and fluid-filled alveoli. Coronavirus disease 19 (COVID-19)-associated ARDS (C-ARDS) is a novel etiology caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that may present with distinct clinical features as a result of the viral pathobiology unique to SARS-CoV-2. In particular, severe injury to the pulmonary vascular endothelium, accompanied by the presence of diffuse microthrombi in the pulmonary microcirculation, can lead to a clinical presentation in which the severity of impaired gas exchange becomes uncoupled from lung capacity and respiratory mechanics. The purpose of this review is to highlight the key mechanistic features of C-ARDS and to discuss the implications these features have on its treatment. In some patients with C-ARDS, rigid adherence to guidelines derived from clinical trials in the pre-COVID era may not be appropriate.

What are the main factors affecting the outcome of tocilizumab therapy in COVID-19-induced cytokine release syndrome?

Recommendations for the treatment of cytokine release syndrome/macrophage activation syndrome (MAS) associated with coronavirus disease-2019 (COVID-19) are still of poor quality. IL-6 is an important therapeutic target as a main mediator of cytokine storm. The aim of our study was to evaluate the tocilizumab (TCZ) efficacy and factors affecting the therapy outcome. This retrospective study included 27 patients treated with TCZ for COVID-19-MAS. All patients in this study were treated with TCZ (intravenously, at a dose of 8 mg kg1 ) in addition to standard therapy. Clinical improvement (survival and decreased oxygen demand) on the 10-14th days and secondary infection rate were assessed. In our 27 treated patients, 14 (51.8%) received TCZ in the intensive care unit (ICU) and seven (25.9%) were need to invasive mechanical ventilation (IMV). Fifteen (55.6%) of these patients revealed a good clinical response (four patients discharge from the ICU and 11 patients who followed-up in nonICU beds showed a decrease in oxygen demand). TCZ was significantly less effective in patients having high Murray lung injury score, low PO2/FiO2 ratio, IMV, and ICU admission (P < .05). Severity of hypoxemia was found as a single independent risk factor in the multivariable analysis (P < .05). Secondary bacterial infections rate was significantly higher in intubated patients (P < .01) or treated in the ICU (P ¼ .01). TCZ was showed limited efficacy for COVID-19-related MAS. The most important predictive indicator for therapy outcome was found as the severity of hypoxemia. In addition, IMV and/or ICU was associated with the poor outcome and high side effect. So, controlled trials are still needed to confirm the indications and timing of TCZ therapy.

Role of fecal calprotectin as a hypoxic intestinal damage biomarker in COVID-19 patients

BackgroundGastrointestinal manifestations of coronavirus disease 2019 (COVID-19) appear to be substantial. Fecal calprotectin is a promising biomarker in COVID-19 associated gastrointestinal inflammation; however, its role in the severity of COVID-19 remains limited. We conducted a study to analyze the relationship between the severity of COVID-19 and hypoxic intestinal damage.MethodsWe assessed the severity of 44 hospitalized COVID-19 pneumonia patients based on the PaO2/FiO2 (P/F) ratio. Inflammatory markers were measured from blood samples, and fecal calprotectin was obtained from stool samples.ResultsMedian levels of fecal calprotectin in COVID-19 patients involved in this study (n = 44) were found to be markedly elevated along with the severity of hypoxemia, as seen in the non-acute respiratory distress syndrome (ARDS) group 21.4 µg/g (5.2–120.9), mild ARDS 54.30 µg/g (5.2–1393.7), moderate ARDS 169.6 µg/g (43.4–640.5), and severe ARDS 451.6 µg/g (364.5–538.6). We also found significant differences in fecal calprotectin levels based on the severity of ARDS (P < 0.001), and although the patients were divided into ARDS and non-ARDS groups (P < 0.001). Furthermore, we found a strong negative correlation between the P/F ratio and fecal calprotectin levels (r = − 0.697, P < 0.001).ConclusionOur findings support the potential role of fecal calprotectin as a biomarker of intestinal inflammation in COVID-19 as a consequence of hypoxic intestinal damage and as suggested by the reduced P/F ratio.

Airways management in SARS-COV-2 acute respiratory failure: A prospective observational multi-center study

ObjectiveFew studies have reported the implications and adverse events of performing endotracheal intubation for critically ill COVID-19 patients admitted to intensive care units. The aim of the present study was to determine the adverse events related to tracheal intubation in COVID-19 patients, defined as the onset of hemodynamic instability, severe hypoxemia, and cardiac arrest. SettingTertiary care medical hospitals, dual-centre study performed in Northern Italy from November 2020 to May 2021. PatientsAdult patients with positive SARS-CoV-2 PCR test, admitted for respiratory failure and need of advanced invasive airways management. InterventionsEndotracheal Intubation Adverse Events. Main variables of interestsThe primary endpoint was to determine the occurrence of at least 1 of the following events within 30 minutes from the start of the intubation procedure and to describe the types of major adverse peri-intubation events: severe hypoxemia defined as an oxygen saturation as measured by pulse-oximetry <80%; hemodynamic instability defined as a SBP 65 mmHg recoded at least once or SBP < 90 mmHg for 30 minutes, a new requirement or increase of vasopressors, fluid bolus >15 mL/kg to maintain the target blood pressure; cardiac arrest. ResultsAmong 142 patients, 73.94% experienced at least one major adverse peri-intubation event. The predominant event was cardiovascular instability, observed in 65.49% of all patients undergoing emergency intubation, followed by severe hypoxemia (43.54%). 2.82% of the patients had a cardiac arrest. ConclusionIn this study of intubation practices in critically ill patients with COVID-19, major adverse peri-intubation events were frequent. Clinical Trial registrationwww.clinicaltrials.gov identifier: NCT04909476

Nomogram and risk calculator for severe hypoxemia after heart valve surgery.

BackgroundHypoxemia is a very common issue in patients undergoing heart valve surgery (HVS), related to poor clinical outcomes. However, studies on severe hypoxemia (SH) after HVS have not been reported. The aims of this study were to identify predictors for SH in patients undergoing HVS and to develop and validate a risk prediction model.MethodsPatients undergoing HVS between 2016 and 2019 in a cardiovascular center were enrolled and were assigned to training and validation sets by a 7:3 ratio. Based on whether patients developed SH, they were divided into two groups. By univariate and multivariate analysis, predictors for SH were identified. Based on the predictors and logistic rule, a nomogram and a risk calculator were generated. The model was evaluated using calibration, discrimination and clinical utility.ResultsThe incidence rates of SH, moderate hypoxemia and mild hypoxemia were respectively 2.4, 23.9, and 58.2%. By multivariate analysis, seven independent risk factors for SH after HVS were identified, including body mass index, chronic obstructive pulmonary disease, renal insufficiency, white blood cell count, serum globulin, cardiopulmonary bypass time, and surgical types. The logistic model demonstrated satisfactory discrimination, calibration and clinical utility in both the training and validation sets. A nomogram and a risk calculator based on the logistic model were generated for easy application. Risk stratification was performed and three risk intervals were defined according to the nomogram and clinical practice. In addition, compared to patients without SH, patients with SH had significantly poorer clinical outcomes.ConclusionsPostoperative hypoxemia was prevalent after HVS, related to poor clinical outcomes. A logistic model including seven independent predictors for SH after HVS were established and validated, which demonstrated satisfactory discrimination, calibration and clinical utility. The results of this study may provide help to individualized risk assessment, early prevention and perioperative management.

Sufentanil target controlled infusion (TCI) versus remifentanil TCI for monitored anaesthesia care for patients with severe tracheal stenosis undergoing fiberoptic bronchoscopy: protocol for a prospective, randomised, controlled study

IntroductionThe use of monitored anaesthesia care (MAC) is necessary and ubiquitous for fiberoptic bronchoscopy. Anaesthetic management of patients with severe tracheal stenosis has always been a challenge. The efficacy and...