Metatranscriptome of human lung microbial communities in a cohort of mechanically ventilated COVID-19 Omicron patients.

The Omicron variant of the severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) infected a substantial proportion of Chinese population, and understanding the factors underlying the severity of the disease and fatality is valuable for future prevention and clinical treatment. We recruited 64 patients with invasive ventilation for COVID-19 and performed metatranscriptomic sequencing to profile host transcriptomic profiles, plus viral, bacterial, and fungal content, as well as virulence factors and examined their relationships to 28-day mortality were examined. In addition, the bronchoalveolar lavage fluid (BALF) samples from invasive ventilated hospital/community-acquired pneumonia patients (HAP/CAP) sampled in 2019 were included for comparison. Genomic analysis revealed that all Omicron strains belong to BA.5 and BF.7 sub-lineages, with no difference in 28-day mortality between them. Compared to HAP/CAP cohort, invasive ventilated COVID-19 patients have distinct host transcriptomic and microbial signatures in the lower respiratory tract; and in the COVID-19 non-survivors, we found significantly lower gene expressions in pathways related viral processes and positive regulation of protein localization to plasma membrane, higher abundance of opportunistic pathogens including bacterial Alloprevotella, Caulobacter, Escherichia-Shigella, Ralstonia and fungal Aspergillus sydowii and Penicillium rubens. Correlational analysis further revealed significant associations between host immune responses and microbial compositions, besides synergy within viral, bacterial, and fungal pathogens. Our study presents the relationships of lower respiratory tract microbiome and transcriptome in invasive ventilated COVID-19 patients, providing the basis for future clinical treatment and reduction of fatality.

[The clinical application of bi-level positive airway pressure noninvasive ventilator for home mechanical ventilation via tracheostomy in patients with amyotrophic lateral sclerosis].

OBJECTIVE: To study the feasibility of the bi-level positive airway pressure (BiPAP) non-invasive ventilator used in home mechanical ventilation for long-term tracheostomy-mechanical ventilation (TMV) in patients with amyotrophic lateral sclerosis (ALS). METHODS: Sixteen patients (12 men and 4 women, mean age 59 years) with ALS were selected for this study at Respiratory Department of the Shougang Hospital, Peking University from January 2002 to March 2008. After the disease had been controlled by anti-infective therapy and comprehensive treatment, the patients received TMV, through the improved ("Xiang's" connection) non-invasive BiPAP ventilator connected with tracheotomy tube, and on-going home mechanical ventilation (HMV). The blood gas was evaluated during invasive ventilation and non-invasive ventilation before discharge. Family members of the patients were trained for the use of non-invasive ventilators. The use of ventilators and the patients' condition were regularly followed and the survival rate calculated. Statistical analysis was carried out by using one-way ANOVA. RESULTS: There was no statistical difference in the blood gas before the use of non-invasive ventilator, 2 h and 1 d after the use of non-invasive ventilator, and before discharge, PaCO2 [(36+/-10), (42+/-11), (41+/-10), (42+/-11) mm Hg (1 mm Hg=0.133 kPa)], PaO2 [(84+/-11), (81+/-12), (87+/-14), (86+/-12) mm Hg], SaO2 [(96.7+/-1.3)%, (96.5+/-0.8)%, (96.8+/-1.2)%, (96.5+/-1.0)%] respectively, (F=1.21, 0.59, 0.97, 0.41, respectively, all P>0.05). All patients had no complaint of uncomfortable use, no intolerance to ventilators, and no ventilator breakdown. Fifteen patients were alive at the end of the follow-up (July 31, 2008). The mean time of using non-invasive ventilator was 39 months (range 4 to 66 months). CONCLUSION: For ALS patients who need long-term ventilation support, the use of BiPAP non-invasive ventilators is a safe and effective alternative for invasive ventilators.

[The efficacy and safety of long term home noninvasive positive pressure ventilation in patients with stable severe chronic obstructive pulmonary disease].

OBJECTIVE: To evaluate the long term efficacy and safety of long term home noninvasive positive pressure ventilation (HNPPV) in stable hypercapnic patients with chronic obstructive pulmonary disease (COPD). METHODS: Forty patients with stable severe COPD [arterial PaCO2>or=55 mm Hg (1 mm Hg=0.133 kPa)] after hospital discharge were divided into 2 groups: the HNPPV group (n=20) with conventional therapy and HNPPV, and the control group (n=20) with conventional therapy only. Parameters before and after 2 year follow-up observation were compared, which included dyspnea grade, scale for accessory muscle use, scoring for emotional disorders, lung function test, arterial blood gases, 6-min walking distance (6MWD), mean pulmonary arterial pressure (mPAP) by electrocardiography, mortality and hospitalization rates. RESULTS: The age, gender, height, weight, dyspnea grade, scale for accessory muscle use, anxiety scores, depression scores, 6MWD, mPAP, arterial PaCO2 and PaO2, FVC, FEV1, and hospitalization rates of the 2 groups on admission were similar (t values were 1.08, 1.15, 1.20, 1.09, 0.86, 0.54, 0.00, 0.00, 0.43, 0.96, 0.76, 0.38, 0.26, 0.24 and 0.87 respectively, all P>0.05). The mortality was reduced slightly by HNPPV but with no statistically significant difference (3/20 and 8/20, respectively, chi2=3.27, P>0.05). After 2 years, the difference of the dyspnea grade, scale for accessory muscle use, anxiety scores, depression scores, arterial PaCO2 and PaO2, 6MWD, mean pulmonary artery pressure, and hospitalization rates in the HNPPV group [2.4+/-0.5, 2.6+/-0.6, 6.9+/-2.1, 6.1+/-1.6, (49.5+/-2.2) mm Hg, (60.8+/-4.7) mm Hg, (213+/-45) m, (30.3+/-2.2) mm Hg, (1.4+/-0.4) times/year] was statistically significant compared to the control group [3.9+/-0.3, 4.8+/-0.4, 11.2+/-2.6, 11.6+/-2.1, (61.5+/-2.3) mm Hg, (52.8+/-2.4) mm Hg, (127+/-23) m, (36.4+/-2.3) mm Hg, (3.9+/-0.3) times/year] (t values were 9.53, 10.83, 4.92, 7.83, 14.07, 5.41, 6.07, 4.81 and 10.22 respectively, all P<0.01). CONCLUSION: Long-term use of home noninvasive positive ventilation in patients with stable severe COPD is effective and safe.

[Long-term follow-up study of moderate chronic obstructive pulmonary disease in elderly patients].

OBJECTIVE: To investigate the prognosis of moderate chronic obstructive pulmonary disease (COPD) in the elderly patients, and to evaluate the factors for long term survival. METHODS: From May 1993, a prospective cohort study was carried out, in which 191 elderly patients with moderate COPD were recruited in Shougang communities, Shijingshan District, Beijing. The general health state, arterial blood gas, pulmonary function test, electrocardiograph, chest X-ray and 6-minute-walk test (6MWT) were recorded. The patients were followed for 12 years. Univariate analysis of survival rate was performed by Kaplan-Meier method. The significance test was done by Log-rank method, and the baseline factors were analyzed using the COX regression model multiplicity. RESULTS: During the 12 years of follow-up, 10 patients were lost because of migration. Twenty-six patients died of non-COPD diseases, while 52 died of COPD. The survival rate was 81.7% (156/191) in 5 years, and 56.9% (103/181) in 12 years. The result with COX multiplicity showed that the important factors for prognosis of the patients were body mass index [BMI, relative risk (RR) = 0.916, 95% confidence intervals (95% CI) = 0.841 - 0.996], forced expired volume in one second (FEV(1), RR = 0.999, 95% CI = 0.998 - 1.000), arterial partial pressure of oxygen (PaO(2), RR = 0.929, 95% CI = 0.892 - 0.967), 6MWT (RR = 0.997, 95% CI = 0.995 - 1.000) and P pulmonale of ECG (RR = 4.081, 95% CI = 1.567 - 10.624). CONCLUSION: The important factors for prognosis of moderate COPD in elderly patients included BMI, FEV(1), PaO(2), 6MWT and P pulmonale in ECG.