[Risk factors and diagnostic methods of intensive care unit-acquired weakness].

OBJECTIVE: To explore the risk factors of intensive care unit-acquired weakness (ICU-AW) and the characteristics of Medical Research Council (MRC) score and electromyogram. METHODS: A case control study was conducted. Patients with mechanical ventilation ≥ 7 days and MRC score admitted to department of respiratory and critical care medicine of China-Japan Friendship Hospital from September 2018 to January 2020 were enrolled, and they were divided into ICU-AW group (MRC score < 48) and non-ICU-AW group (MRC score ≥ 48) according to MRC score. The general situation, past medical history, related risk factors, MRC score, respiratory support mode, laboratory examination results, electromyogram examination results, ICU-AW related treatment, outcome and length of ICU stay were collected, and the differences between the two groups were compared. The risk factors of ICU-AW were analyzed by binary multivariate Logistic regression, and the characteristics of MRC score and electromyogram were analyzed. RESULTS: A total of 60 patients were enrolled in the analysis, including 17 patients in ICU-AW group and 43 patients in non-ICU-AW group. Univariate analysis showed that there were significant differences in acute physiology and chronic health evaluation II (APACHE II) score, sequential organ failure assessment (SOFA) score, brain natriuretic peptide (BNP), blood urea nitrogen (BUN) on the first day of ICU admission and the ratio of invasive mechanical ventilation between ICU-AW group and non-ICU-AW group [APACHE II score: 21 (18, 25) vs. 18 (15, 22), SOFA score: 7 (5, 12) vs. 5 (3, 8), BNP (ng/L): 364.3 (210.1, 551.2) vs. 160.1 (66.8, 357.8), BUN (mmol/L): 9.9 (6.2, 17.0) vs. 6.0 (4.8, 9.8), invasive mechanical ventilation ratio: 88.2% vs. 46.5%, all P < 0.05]. Binary multivariate Logistic regression analysis showed no independent risk factor for ICU-AW. The average MRC score of 17 ICU-AW patients was 33±11. The limb weakness was symmetrical, and the proximal limb weakness was the main manifestation. Electromyography examination showed that the results of nerve conduction examination in ICU-AW patients mainly revealed that the amplitude of compound muscle action potential (CMAP) and sensory nerve action potentials (SNAP) were decreased, and the conduction velocity was slowed down; needle electromyography showed increased area of motor unit potential (MUP), prolonged time limit and a large number of spontaneous potentials. Prognosis evaluation showed that compared with non-ICU-AW group, patients in ICU-AW group underwent more tracheotomy (70.6% vs. 11.6%), longer length of ICU stay (days: 57±52 vs. 16±8), and more rehabilitation treatment (58.8% vs. 14.0%), and the differences were statistically significant (all P < 0.01). CONCLUSIONS: The occurrence of ICU-AW may be related to high APACHE II score and SOFA score, high levels of BNP and BUN on the first day of ICU admission and the proportion of invasive mechanical ventilation, but the above factors are not independent risk factors for ICU-AW. The MRC score of ICU-AW patients was characterized by symmetrical limb weakness, mainly proximal limb weakness; in electromyography examination, the nerve conduction examination results mainly showed that CMAP and SNAP amplitude were decreased, and conduction velocity was slowed down; needle electromyography examination showed increased MUP area, prolonged duration and a large number of spontaneous potentials.

Circulating and Pulmonary T-cell Populations Driving the Immune Response in Non-HIV Immunocompromised Patients with Pneumocystis jirovecii Pneumonia.

Background: Previous studies in human subjects have mostly been confined to peripheral blood lymphocytes for Pneumocystis infection. We here aimed to compare circulating and pulmonary T-cell populations derived from human immunodeficiency virus (HIV)-uninfected immunocompromised patients with Pneumocystis jirovecii pneumonia (PCP) in order to direct new therapies. Methods: Peripheral blood and bronchoalveolar lavage samples were collected from patients with and without PCP. Populations of Th1/Tc1, Th2/Tc2, Th9/Tc9, and Th17/Tc17 CD4+ and CD8+ T cells were quantified using multiparameter flow cytometry. Results: No significant differences were found between PCP and non-PCP groups in circulating T cells. However, significantly higher proportions of pulmonary Th1 and Tc9 were observed in the PCP than in the non-PCP group. Interestingly, our data indicated that pulmonary Th1 was negatively correlated with disease severity, whereas pulmonary Tc9 displayed a positive correlation in PCP patients. Conclusions: Our findings suggest that pulmonary expansion of Th1 and Tc9 subsets may play protective and detrimental roles in PCP patients, respectively. Thus, these specific T-cell subsets in the lungs may serve as targeted immunotherapies for patients with PCP.

Expression profiling analysis of long noncoding RNAs in a mouse model of ventilator-induced lung injury indicating potential roles in inflammation.

The key regulators of inflammation underlying ventilator-induced lung injury (VILI) remain poorly defined. Long noncoding RNAs (lncRNAs) have been implicated in the inflammatory response of many diseases; however, their roles in VILI remain unclear. We, therefore, performed transcriptome profiling of lncRNA and messenger RNA (mRNA) using RNA sequencing in lungs collected from mice model of VILI and control groups. Gene expression was analyzed through RNA sequencing and quantitative reverse transctiption polymerase chain reaction. A comprehensive bioinformatics analysis was used to characterize the expression profiles and relevant biological functions and for multiple comparisons among the controls and the injury models at different time points. Finally, lncRNA-mRNA coexpression networks were constructed and dysregulated lncRNAs were analyzed functionally. The mRNA transcript profiling, coexpression network analysis, and functional analysis of altered lncRNAs indicated enrichment in the regulation of immune system/inflammation processes, response to stress, and inflammatory pathways. We identified the lncRNA Gm43181 might be related to lung damage and neutrophil activation via chemokine receptor chemokine (C-X-C) receptor 2. In summary, our study provides an identification of aberrant lncRNA alterations involved in inflammation upon VILI, and lncRNA-mediated regulatory patterns may contribute to VILI inflammation.

Respiratory care practices and requirements for respiratory therapists in Beijing intensive care units.

BACKGROUND: Respiratory therapist (RT) is a nascent career in China, so little information is available about intensive care unit (ICU) respiratory care resources and practices, requirements for RTs, and barriers to recruit RTs. METHODS: Using survey methodology, we designed and mailed a questionnaire to ICU supervisors and staffs at all 106 ICUs within 46 tertiary and university-affiliated hospitals in Beijing. RESULTS: We obtained responses from 72 of 106 ICUs. There were 644 ICU beds, 18 RTs, 464 physicians, and 1,362 nurses in these 72 ICUs. The ratios of invasive and noninvasive ventilators to beds were 0.7/1 and 0.31/1. Nineteen ICUs were not equipped with noninvasive ventilators; 18 had started using noninvasive ventilation only within the last 5 years; 9 had only nasal cannulas for conventional oxygen therapy. Of 194 responders, 57.8% implemented spontaneous breathing trial before extubation; 23.7% never monitored airway temperature while using heated humidifier; 56.7% changed circuits once a week; and 20.6% every 1-3 days. The survey indicated that 91.2% had heard of the profession of RT before, mostly by attending academic conferences; 86.1% believed respiratory care should be provided by RTs. Due to the paucity of trained RTs, only 9.7% (7/72) ICUs had actually recruited RTs. The specific tasks supposed to be assigned to RTs were mechanical ventilation, chest physiotherapy, and airway care. CONCLUSIONS: ICU respiratory care equipment and the knowledge to use them are insufficient. Important differences exist in respiratory care practice, which is mostly provided by nurses and physicians. RTs have been gradually recognized and accepted by ICU staff, while professional training and education are needed.

[Non-invasive positive pressure ventilation in patients with acute hypoxemic respiratory failure: a prospective cohort study].

OBJECTIVE: To investigate the clinical effect of non-invasive positive pressure ventilation (NPPV) on acute hypoxemic respiratory failure (AHRF), and to look for predictors of failure of NPPV in patients with AHRF. METHODS: In the cohort study, the clinical data of patients with AHRF in respiratory intensive care unit (RICU) of Beijing Chaoyang Hospital from January 2004 to December 2007 were collected prospectively. Patients were divided into successful group and failure group according to outcome of NPPV. Basic clinical information, NPPV mode and duration, vital signs, arterial blood gas analysis, and oxygenation index (PaO(2)/FiO(2)) before and 2 hours, 24 hours after NPPV were analyzed and compared between two groups. RESULTS: (1)The NPPV successful rate in 59 cases was 62.7% (37/59). (2)Compared with failure group, mean age, the ratio of patients in whom respiratory failure were induced by pulmonary infection were lower in successful group (both P<0.01). There was no difference in PaO(2)/FiO(2)between two groups before NPPV, but PaO(2)/FiO(2) in successful group was markedly higher than those of failure group after 2 hours and 24 hours of NPPV (P<0.05 and P<0.01), while heart rate (HR), respiratory rate (RR) were significantly lower (all P<0.01). (3)Logistic regression analysis identified age > or = 60 years [odds ratio (OR) 8.30, 95% confidence interval (CI) 2.49-27.60, P=0.002], pulmonary infection as underlying disease of respiratory failure (OR 6.19, 95%CI 1.90-20.20, P=0.027), PaO(2)/FiO(2)<150 mm Hg (1 mm Hg=0.133 kPa) after 2 hours of NPPV (OR 3.65, 95%CI 1.20-11.04, P=0.044), HR>100 times/min after 24 hours of NPPV (OR 7.45, 95%CI 2.15-25.58, P=0.010), and RR>30 times/min after 24 hours of NPPV (OR 7.26, 95%CI 1.88-24.49, P=0.018) as risk factors independently associated with failure of NPPV. CONCLUSION: NPPV can be the first line treatment for severe AHRF patients without absolute contraindication, while patients of older age with pulmonary infection, the risk of failure of NPPV is higher. Lack of improvement in cardiorespiratory and oxygenation condition after a short period of NPPV is the predictor of NPPV failure.

[Non-invasive positive pressure ventilation in patients with acute respiratory distress syndrome: a prospective cohort study].

OBJECTIVE: To investigate the efficiency of the application of non-invasive positive pressure ventilation (NPPV) as a first-line intervention in patients with acute respiratory distress syndrome (ARDS). METHODS: A prospective cohort study was designed to analyze the clinical data of patients with ARDS in respiratory intensive care unit (RICU) of Beijing Chaoyang Hospital admitted between January 2004 and December 2007. RESULTS: (1)31 patients, age (49+/-17) years, with acute physiology and chronic health evaluation II (APACHEII) score of 14+/-8 and oxygenation index (PaO(2)/FiO(2) of (123+/-32) mm Hg (1 mm Hg=0.133 kPa), were enrolled in the study. There were 23 males and 8 females. (2)The successful rate of NPPV was 74.2% (23/31) and it was significantly higher in patients without pulmonary infection than that in patients with pulmonary infection (100% vs. 60%, P=0.017). (3)In the successful group, heart rate (HR), respiratory rate (RR) and PaO(2)/FiO(2) were improved significantly at the time of 2 hours and 24 hours of NPPV compared with NPPV before (all P<0.01), while there was no significant improvement observed in the failure group. Furthermore, an increase in arterial partial pressure of carbon dioxide (PaCO(2)) was observed in the latter (P<0.05). No serious complications were seen in association with NPPV in all recruited patients. CONCLUSION: NPPV may be the first-line intervention for a selected group of ARDS patients, while invasive ventilation should be considered for those patients with high risk of NPPV failure as indicated by worsening of vital signs and arterial blood gas analysis after a short time of using NPPV, and also in cases where pulmonary infection is the underlying disease of ARDS.

[A questionnaire survey on the current practices of respiratory care in intensive care unit in 30 provinces].

OBJECTIVE: To investigate respiratory care equipment, operators and conditions of performance in intensive care units (ICU), with the aim of providing data for standardization and developing respiratory care in China. METHODS: A questionnaire survey was performed in one national and two international conferences in August, 2006. Four hundred and ninety-one doctors and nurses from 320 ICUs in 264 tertiary hospitals responded. RESULTS: Ratios of invasive and noninvasive mechanical ventilators to beds were 0.52:1 (2 189/4 185) and 0.16:1 (672/4 185), respectively. Of 320 ICUs, ratios of ICU equipped with ultrasound, jet nebulizers and MDI were 55.9% (179/320), 33.8% (108/320) and 12.1% (39/320), respectively, and percentages of doctors in charge of setting modes and parameters, weaning and extubation were 92.1%, 93.1%, 83.5%, respectively. Suction (93.9%), humidification (90.2%), aerosol therapy (91.6%) and circuit changing (83.7%) were nurses' duties. Among 491 responders, 40.9% of them implemented spontaneous breathing trials (SBT) before weaning, 13.4% were ignorant of it, and 12.8% never. 27.1% of ICU never monitored air temperature during invasive mechanical ventilation, 34.4% provided humidification by instilling or pumping saline continuously for those patients who were weaned from ventilators but not extubated, 55.6% checked ventilator before use. Ventilator circuits were changed once a week in 48.1%, 1-3 days in 25.0% and 3-5 days in 14.7%. CONCLUSION: The quantity of ventilators in the ICU has increased, but other practical respiratory care equipment have not been used widely. Most of respiratory care services are still provided by nurses and doctors, lacking professional staffs. The management is evidently variable but without a standardized guideline.