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.

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.

Prognostic factors for severe Pneumocystis jiroveci pneumonia of non-HIV patients in intensive care unit: a bicentric retrospective study.

BACKGROUND: Pneumocystis jiroveci pneumonia (PJP) in non-HIV patients is still a challenge for intensivists. The aim of our study was to evaluate mortality predictors of PJP patients requiring Intensive care unit (ICU) admission. METHODS: Retrospectively review medical records of patients with diagnosis of PJP admitted to four ICUs of two academic medical centers from October 2012 to October 2015. RESULTS: Eighty-two patients were enrolled in the study. Overall hospital mortality was 75.6 %. Compared with survivors, the non-survivors had older age (55 ± 16 vs. 45 ± 17, p = 0.014), higher APACHE II score (20 ± 5 vs. 17 ± 5, p = 0.01), lower white blood cell count (7.68 ± 3.44 vs. 10.48 ± 4.62, p = 0.005), less fever (80.6%vs. 100 %, p = 0.033), more hypotension (58.1 % vs. 20 %, p = 0.003), more pneumomediastinum (29 % vs. 5 %, p = 0.027). Logistic regression analysis demonstrated that age [odds ratio (OR)1.051; 95 % CI 1.007-1.097; p = 0.022], white blood cell count [OR 0.802; 95 % CI 0.670-0.960; p = 0.016], and pneumomediastinum [OR 16.514; 95 % CI 1.330-205.027; p = 0.029] were independently associated with hospital mortality. CONCLUSIONS: Mortality rate for non-HIV PJP patients requiring ICU admission was still high. Poor prognostic factors included age, white blood cell count and pneumomediastinum.

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.

[The experience of extracorporeal membrane oxygenation for severe acute respiratory failure in adults].

OBJECTIVE: To summarize the experience of extracorporeal membrane oxygenation (ECMO) for patients with severe acute respiratory failure in adults and to investigate the factors associated with death. METHODS: The clinical data of patients with severe acute respiratory failure supported with ECMO in respiratory intensive care unit of Beijing Chaoyang Hospital from November 2009 to December 2011 were prospectively collected and analyzed. The data included general condition before EMCO, blood gas analysis, hemodynamics, ventilator settings of mechanical ventilation and complications during ECMO. The primary outcome was death or severe disability within 3 months. Statistical software of SPSS (version 16.0) was used for data analysis. RESULTS: Twenty-five patients with severe respiratory failure received ECMO treatment, of which 16 patients were analyzed. The mean age was (45 ± 14) years old (range, 22 - 64 years old). Thirteen patients were male. Before ECMO, all of the patients were treated with invasive positive pressure ventilation for (72 ± 64) hours. Eight patients had been treated with noninvasive ventilation for a median of 55(10-114) hours. Patients had severe respiratory failure despite advanced mechanical ventilator support. The mean PaO2/fraction of inspired oxygenation (FiO2) ratio was (54 ± 18) mm Hg (1 mm Hg = 0.133 kPa), positive end-expiratory pressure (PEEP) was (11 ± 6) cm H2O(1 cm H2O = 0.098 kPa), Murray lung injury score was 3.6 ± 0.5, serum lactate was (2.5 ± 2.0) mmol/L, serum white blood cell count was (16 ± 6)×10(9)/L, and APACHEII score was 17 ± 8. All of the patients were treated with venous-venous ECMO (VV-ECMO). The change of mechanical ventilation settings were (pre-ECMO vs 2 hours post-ECMO): FiO2 1.0 vs 0.55 ± 0.21, PEEP (11 ± 6) vs (9 ± 6) cm H2O, V(T) (6.8 ± 2.2) vs (4.4 ± 2.0) ml/kg PBW, peak airway pressure (27 ± 8) vs (24 ± 7) cm H2O, respiratory rate (37 ± 10) vs (23 ± 10) breaths/min. Arterial blood gas, including pH, PaO2 and PaCO2 were significantly improved after ECMO running 24 and 48 hours (P < 0.05). The mean VV-ECMO support interval was (9.7 ± 9.6) days (range, 2 - 41 days). Ten patients were successfully weaned from ECMO, of whom 2 died in ICU. Three patients died during ECMO, while another 3 patients died after withdrawal of further treatment. Eight patients survived to 3 months without severe disability. In a multi-variate Cox regression model, pre-ECMO factors including lower PaO2/FiO2 and increasing white blood cell count were associated with increased risks of death (RR was 0.733, 1.701 respectively, both P values < 0.05). CONCLUSIONS: VV-ECMO is a potentially effective approach for severe acute respiratory failure. PaO2/FiO2 and white blood cell count pre-ECMO may be the risk factors for poor outcome.

[Clinical observation of therapeutic effect of extracorporeal membrane oxygenation in patients with acute respiratory distress syndrome].

OBJECTIVE: To investigate the therapeutic effects and safety of extracorporeal membrane oxygenation (ECMO) in patients with acute respiratory distress syndrome (ARDS). METHODS: ECMO were initiated in 6 patients with ARDS, not responding to conventional mechanical ventilation. Oxygenation status, positive end-expiratory pressure (PEEP) level, and fraction of inspired oxygen [FiO(2)] were compared before and after treatment with ECMO, while the adverse effects of ECMO were recorded. RESULTS: In 6 cases, pulse blood oxygen saturation [SpO(2)] was elevated (0.45-0.92 up to 0.94-1.00), PEEP level [cm H(2)O, 1 cm H(2)O=0.098 kPa] and [FiO(2)] were lowered [PEEP: 10.0-22.0 down to 4.0-15.0; FiO(2): 1.00 down to 0.30-0.60] after treatment with ECMO. Of 6 cases, 2 patients with severe influenza A/H1N1 pneumonia finally died of shock; 1 patient with severe influenza A/H1N1 pneumonia and 1 patient with Klebsiella pneumoniae pneumonia were withdrawn from ECMO treatment because of deterioration of the disease. One patient suffering from Cytomegalovirus pneumonia and another with Acinetobacter baumannii pneumonia were successfully discharged from hospital with recovery. The main complications were bleeding and hemolysis. CONCLUSIONS: ECMO could improve gas exchange, oxygenation and partially replace pulmonary function. Patients with ARDS should be treated with ECMO early if artificial ventilation treatment was unresponsive.

[Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome caused by novel 2009 influenza A (H1N1) virus].

OBJECTIVE: To summarize the clinical experiences and indications of extracorporeal membrane oxygenation (ECMO) for severe ARDS caused by novel 2009 influenza A (H1N1) virus. METHODS: All ECMO cases with severe ARDS associated with novel 2009 influenza A (H1N1) virus were analyzed in 5 intensive care units (ICUs) from 5 different hospitals in Beijing and Tianjin. A physician experienced in ECMO handling collected the relevant data, including general conditions pre and post-EMCO, efficacy and complication parameters, ventilator settings of mechanical ventilation and clinical outcomes. The statistical software of SPSS (version 11.5) was used for data analysis. RESULTS: 18 cases of novel H1N1 influenza with severe ARDS received ECMO. There were 9 males and 9 females (all pregnant). The mean age was (33 ± 11) years old. Eight were complicated with pulmonary barotraumas (6 of pneumothorax). Prior to ECMO, the patients underwent noninvasive and invasive positive pressure ventilation for 1 day and 60 hours respectively. Physiological parameters 2-6 hours prior to ECMO use were: (53 ± 14) mm Hg of PaO2/FiO2, (17 ± 5) cm H2O of positive end expiratory pressure (PEEP), 3.80 ± 0.29 of Murray lung injury score, (7.38 ± 0.10) of arterial pH, (3.3 ± 2.3) mmol/L of serum lactate, 16 ± 8 of APACHE II score. All patients treated venous-venous ECMO (VV-ECMO) for a mean duration of 8 days (range: 2 - 168). Settings of mechanical ventilation (prior to ECMO vs 2 hours post-ECMO) were: peak airway pressure (31 ± 7) vs (25 ± 6) cm H2O, respiratory rate (15 ± 4) vs (22 ± 6) breaths/min, FiO2 0.8 - 1.0 vs 0.35 - 0.50, PEEP (16 ± 5) vs (12 ± 4) cm H2O. Arterial blood gas (pH, PaO2 and PaCO2) post-ECMO of 2 hours and 24-hour significantly improved (P < 0.05). Seven patients died during ECMO, 11 patients were successfully weaned from ECMO. And 8 of them survived and were discharged. One patient stayed in ICU and 2 died in ICU. CONCLUSIONS: As an effective measure of respiratory supports, ECMO may provide pulmonary rest and improve gas exchanges in severe ARDS induced by novel H1N1 Influenza.

Retrospective Study of Critically Ill COVID-19 Patients With and Without Extracorporeal Membrane Oxygenation Support in Wuhan, China.

Background: Extracorporeal membrane oxygenation (ECMO) might benefit critically ill COVID-19 patients. But the considerations besides indications guiding ECMO initiation under extreme pressure during the COVID-19 epidemic was not clear. We aimed to analyze the clinical characteristics and in-hospital mortality of severe critically ill COVID-19 patients supported with ECMO and without ECMO, exploring potential parameters for guiding the initiation during the COVID-19 epidemic. Methods: Observational cohort study of all the critically ill patients indicated for ECMO support from January 1 to May 1, 2020, in all 62 authorized hospitals in Wuhan, China. Results: Among the 168 patients enrolled, 74 patients actually received ECMO support and 94 not were analyzed. The in-hospital mortality of the ECMO supported patients was significantly lower than non-ECMO ones (71.6 vs. 85.1%, P = 0.033), but the role of ECMO was affected by patients' age (Logistic regression OR 0.62, P = 0.24). As for the ECMO patients, the median age was 58 (47-66) years old and 62.2% (46/74) were male. The 28-day, 60-day, and 90-day mortality of these ECMO supported patients were 32.4, 68.9, and 74.3% respectively. Patients survived to discharge were younger (49 vs. 62 years, P = 0.042), demonstrated higher lymphocyte count (886 vs. 638 cells/uL, P = 0.022), and better CO2 removal (PaCO2 immediately after ECMO initiation 39.7 vs. 46.9 mmHg, P = 0.041). Age was an independent risk factor for in-hospital mortality of the ECMO supported patients, and a cutoff age of 51 years enabled prediction of in-hospital mortality with a sensitivity of 84.3% and specificity of 55%. The surviving ECMO supported patients had longer ICU and hospital stays (26 vs. 18 days, P = 0.018; 49 vs. 29 days, P = 0.001 respectively), and ECMO procedure was widely carried out after the supplement of medical resources after February 15 (67.6%, 50/74). Conclusions: ECMO might be a benefit for severe critically ill COVID-19 patients at the early stage of epidemic, although the in-hospital mortality was still high. To initiate ECMO therapy under tremendous pressure, patients' age, lymphocyte count, and adequacy of medical resources should be fully considered.

[Causes of respiratory failure complicating interstitial lung disease and application value of mechanical ventilation].

OBJECTIVE: To investigate the potential causes of respiratory failure in patients with interstitial lung disease (ILD) and evaluate the application value of mechanical ventilation (MV) in its treatment. METHODS: This study included the clinical data of 47 ILD patients (29 males and 18 females) complicating respiratory failure and admitted to respiratory care unit (RICU) for receiving MV at Beijing Chaoyang Hospital from January 1, 1998 to June 30, 2008. The median age was 67 years old. And a retrospective analysis was conducted for clinical characteristics, potential causes of respiratory failure, RICU treatment, prognosis and causes of death, etc. RESULTS: The causes of respiratory failure were as follows: respiratory infections (n = 18, 38.3%), respiratory infection superimposed aggravated ILD (n = 15, 31.9%), pulmonary embolism (n = 8, 17.0%), ILD with acute exacerbation (n = 5, 10.6%) and heart failure (n = 1, 2.1%). And the mortality rates of RICU were 55.6% (10/18), 73.3% (11/15), 5/8, 4/5 and 1/1 respectively. Upon initial admission into RICU, 31 cases received noninvasive ventilation and 16 cases tracheal intubation. The mortality rates were 54.8% and 87.5% respectively. And there was statistically significant difference between the groups (chi(2) = 5.014, P = 0.025). In all patients, the RICU mortality rate was 66.0% (31/47) and the hospital mortality rate 70.2% (33/47). CONCLUSIONS: Respiratory infection, pulmonary embolism and acute exacerbation of ILD are the main common causes of respiratory failure in ILD patients. Noninvasive ventilation therapy is clinically preferable to invasive ventilation for ILD patients with respiratory failure.

Erratum for Alveolar Type II Cells Escape Stress Failure Caused By Tonic Stretch Through Transient Focal Adhesion Disassembly.

[This corrects the article DOI: 10.7150/ijbs.7.588.].

Chemoprophylaxis, diagnosis, treatments, and discharge management of COVID-19: An evidence-based clinical practice guideline (updated version).

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of a rapidly spreading illness, coronavirus disease 2019 (COVID-19), affecting more than seventeen million people around the world. Diagnosis and treatment guidelines for clinicians caring for patients are needed. In the early stage, we have issued "A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)"; now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based guideline. We formed a working group of clinical experts and methodologists. The steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas: chemoprophylaxis, diagnosis, treatments, and discharge management. We searched the literature for direct evidence on the management of COVID-19, and assessed its certainty generated recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Recommendations were either strong or weak, or in the form of ungraded consensus-based statement. Finally, we issued 34 statements. Among them, 6 were strong recommendations for, 14 were weak recommendations for, 3 were weak recommendations against and 11 were ungraded consensus-based statement. They covered topics of chemoprophylaxis (including agents and Traditional Chinese Medicine (TCM) agents), diagnosis (including clinical manifestations, reverse transcription-polymerase chain reaction (RT-PCR), respiratory tract specimens, IgM and IgG antibody tests, chest computed tomography, chest x-ray, and CT features of asymptomatic infections), treatments (including lopinavir-ritonavir, umifenovir, favipiravir, interferon, remdesivir, combination of antiviral drugs, hydroxychloroquine/chloroquine, interleukin-6 inhibitors, interleukin-1 inhibitors, glucocorticoid, qingfei paidu decoction, lianhua qingwen granules/capsules, convalescent plasma, lung transplantation, invasive or noninvasive ventilation, and extracorporeal membrane oxygenation (ECMO)), and discharge management (including discharge criteria and management plan in patients whose RT-PCR retesting shows SARS-CoV-2 positive after discharge). We also created two figures of these recommendations for the implementation purpose. We hope these recommendations can help support healthcare workers caring for COVID-19 patients.

[Exogenous pulmonary surfactant replacement combined with recruitment maneuver in prevention of alveolar derecruitment in rabbits with acute respiratory distress syndrome].

OBJECTIVE: To investigate the effects of exogenous pulmonary surfactant (PS), recruitment maneuver (RM) and the combination of RM with PS in rabbits with acute respiratory distress syndrome (ARDS). METHODS: ARDS models were induced in 28 New Zealand white rabbits by repeated airway lavage with normal warm saline, and the animals were ventilated with volume controlled ventilation [VCV, VT 8 ml/kg, RR 40/min, PEEP 3 cm HO2O (1 cm HO2O = 0.098 kPa)]. All the rabbits were randomly divided by random digit table into 4 groups (n=7 each): a control group, a PS group, a RM group and a PS + RM group. Arterial blood gas analysis, peak inflating pressure (PIP) and static compliance of the respiratory system (Cst) were measured. All the animals were sacrificed at 4h of experimental interventional therapy for the examination of pulmonary pathology. RESULTS: (1) The mean PaO2 in the PS group,the RM group and the PS+ RM group [(234 +/- 42)mm Hg,(231 +/- 17) mm Hg, (253 +/- 52)mm Hg(1 mm Hg = 0.133 kPa), respectively] was significantly higher than that in the control group [(74 +/- 15) mm Hg, F = 84.201, P < 0.01]. The improvement in the PS group and the PS + RM group was stable, but in the RM group, the PaO2 gradually decreased. (2) The PaCO2 in the control group [(56 +/- 11) mm Hg] was significantly higher than that in the PS group and the PS + RM group [(46 +/- 10) mm Hg, (46 +/- 10) mm Hg, respectively, F = 4.234, P < 0.05]. The PaCO2 in the RM group gradually increased. (3) The respective PIP in the 4 groups was (33 +/- 2), (23 +/- 1), (24 +/- 2), (22 +/- 1) cm H2O; Cst was (1.1 +/- 0.3), (1.7 +/- 0.3), (1.5 +/- 0.1), (1.9 +/- 0.4) ml/cm H2O. Compared with the baseline and with the control group, PIP and Cst in the 3 intervention groups improved significantly (F = 74.911, 15.863, P < 0.01). The improvement of Cst in the PS + RM group was better than that in the RM group (q = 2.58, P < 0.05). (4)The lung injury score in the PS group, the RM group and the PS +RM group (3.9 +/- 0.8, 6.1 +/- 0.7, 4.2 +/- 0.6, respectively) were significantly lower than that in the control group (13.5 +/- 0.7, F = 369.6, P < 0.01). The lung injury in the RM group was more severe than that in the PS and PS + RM group (q = 6.35, 5.70, all P < 0.01). CONCLUSIONS: Exogenous PS replacement therapy can improve oxygenation and the compliance of the respiratory system in ARDS rabbits . RM can also improve oxygenation and lung mechanics temporarily, but it may induce ventilator associated lung injury(VALI). PS replacement combined with RM therapy can alleviate VALI and is more effective in improving oxygenation and lung mechanics.

[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.

[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.

[Effects of prone position ventilation combined with recruitment maneuver on oxygenation and shunt in canines with acute respiratory distress syndrome].

OBJECTIVE: To evaluate the effects of prone position ventilation (PPV) combined with recruitment maneuver (RM) on oxygenation and intrapulmonary shunting in oleic acid-induced acute respiratory distress syndrome (ARDS) in canines while ventilated with lung protective ventilation strategy. METHODS: ARDS was induced by oleic acid in 24 dogs, and the animals were ventilated with volume controlled ventilation (VCV), 16 cm H2O (1 cm H2O = 0.098 kPa) of positive end-expiratory pressure (PEEP) and small tidal volumes (V(T) 10 ml/kg). All the dogs were randomly divided by random digit table into 4 groups (6 each), a control group (supine position, SP group), a prone position group (PP group), a supine position + RM group (SPRM group), and a prone position + RM group (PPRM group), and then were ventilated by VCV for 4 h. Arterial and mixed venous blood gas analyses were measured. Data were analyzed using the SPSS for windows (version 11.5). Results were expressed as x +/- s. Homogeneity of variance test was performed. The differences in means were calculated using one-way ANOVA. Post-hoc multiple comparisons of means were performed using Least Significant Difference. Nonparametric tests for several independent samples were performed to compare differences between the ranks in the groups studied. P value of < 0.05 was considered statistically significant. RESULTS: (1) At 15 min, PaO2/FiO2 in the SPRM group, the PP group and the PPRM group [(368 +/- 45) mm Hg (1 mm Hg = 0.133 kPa), (349 +/- 80) mm Hg, ( 423 +/- 43) mm Hg, respectively] was significantly higher than that in the SP group [(269 +/- 72) mm Hg, q = 2.77, 2.23, 4.31, respectively, all P < 0.05]. At 2 h, PaO2/FiO2 in the PP group and the PPRM group [(401 +/- 82) mm Hg, (416 +/- 23) mm Hg, respectively] was significantly higher than that in the SP group [(232 +/- 40) mm Hg, q = 3.99, 4.35, respectively, all P < 0.05]. At 4 h, PaO2/FiO2 in the PPRM group [(384 +/- 68) mm Hg] was significantly higher than that in the SP group [(256 +/- 75) mm Hg], that in the SPRM group [(267 +/-92) mm Hg] and that in the PP group [(284 +/- 83) mm Hg, q = 2.75, 2.56, 2.17, respectively, all P < 0.05]. (2) Intrapulmonary shunt (Q(S)/Q(T)) in the PP group was significantly decreased compared with that in the SP group from 30 min to 2 h [30 min (9.9 +/- 4.4)% vs (15.0 +/- 1.6)%, 1 h (9.7 +/- 4.5)% vs (16.0 +/- 2.0)%, 2 h (8.3 +/- 4.6)% vs (16.2 +/- 1.8)%, q = 2.86, 3.00, 3.65, respectively, all P < 0.05]. The Q(S)/Q(T), in the PPRM group was significantly decreased compared with that in the SP group from 30 min to 4 h [30 min (10.0 +/- 1.0)% vs (15.0 +/- 1.6)%, 1 h (10.4 +/- 2.7)% vs (16.0 +/- 2.0)%, 2 h (10.2 +/- 0.7)% vs (16.2 +/- 1.8)%, 4 h (10.1 +/- 1.1)% vs (15.7 +/- 1.7)%, q = 2.80, 2.67, 2.75, 2.99, respectively, all P < 0.05]. CONCLUSIONS: On the basis of small tidal volume lung and PEEP protective ventilation strategy, combining prone position and recruitment maneuver was more effective and showed a synergistic effect on improving oxygenation and intrapulmonary shunt.

[Clinical features of invasive pulmonary aspergillosis in critically ill patients with chronic respiratory diseases].

OBJECTIVE: To describe the clinical features of invasive pulmonary aspergillosis (IPA) in critically ill patients with chronic respiratory diseases (CRD) and to estimate its value for early diagnosis and treatment. METHODS: Retrospective study of critically ill CRD patients with positive Aspergillus from sputum or bronchial alveolar lavage fluid in a respiratory ICU of a teaching hospital. RESULTS: There were 149 CRD patients admitted between October 2004 and February 2007. Among these patients, 16 cases of IPA (11 COPD,4 COPD with asthma, 1 bronchiectasis ) were collected. Three cases fulfilled the criteria of proven IPA, 10 of probable and 3 of possible IPA. Corticosteroids and multiple broad-spectrum antibiotics had been administered to 12 and 15 patients respectively. Fifteen patients experienced worsening of bronchospasm leading to acute respiratory failure. Nine patients failed to improve on noninvasive ventilation, and 14 patients required invasive ventilation. Twelve patients had infiltrates on chest X-ray. Before the appearance of infiltrates, bronchoscopy showed tracheobronchial inflammatory changes with severe bronchospasm. With the rapid progression of infiltrates, bronchial pseudomembrane was observed, with increased white blood cell count and exacerbated radiology findings. The rate of positive isolation of Aspergillus from airway samples during early stage was lower than late stage (2/12 vs 10/12). Early treatment was started before the appearance of infiltrates in 4 patients, all of whom survived. Although antifungal treatment was started when IPA was suspected after the appearance of infiltrates, 11 of 12 patients died in septic shock or multiple-organ failure. CONCLUSIONS: IPA occurring in critically ill CRD patients is not rare and has a poor prognosis. Early diagnosis and empirical antifungal treatment based on certain clinical features may improve the outcome.

[Nitric oxide inhalation improves alveolar liquid clearance in rabbit with endotoxin induced acute lung injury].

OBJECTIVE: To investigate the effects of nitric oxide (NO) inhalation (iNO) on alveolar liquid clearance (ALC), alveolar permeability, and lung edema, and its possible mechanism. METHODS: Eighteen male rabbits were challenged with endotoxin, and they were randomly assigned into three groups: mechanical ventilator (MV) group [volume control ventilation: tidal volume (V(T)) 15 ml/kg, respiration rate (RR) 40 beats/minute, positive end-expiratory pressure (PEEP): 5 cm H(2)O (1 cm H(2)O=0.098 kPa)], high; NO ( 40 x 10(-6) NO, HNO) group and low concentration; NO (10 x 10(-6) NO, LNO) group. Indexes including haemodynamics, blood gas analysis, and mechanics of breathing were determined after MV at different time points in each group. The rabbits were sacrificed after MV lasting for 4 hours. Wet/dry weight (W/D) ratio of the lung was calculated, and the condition of alveolar exudation was observed. RESULTS: (1) Oxygenation index (PaO(2)/FiO(2)) in HNO group and LNO group were higher than those in MV group at 0.5 hour after treatment. (2) The peak pressure of airway (Ppeak) and plateau pressure of airway (Pplat) in LNO group were lower than those in MV group at 0.5, 2 and 4 hours after treatment (P<0.05 or P<0.01). Ppeak at 4 hours, Pplat at 2 hours and 4 hours were lower in HNO group as compared with those in MV group (P<0.05 or P<0.01). Pplat in LNO group was lower than that in HNO group at 2 hours and 4 hours (both P<0.01). (3) Alveolar exudation in HNO group and LNO group was milder than that in MV group (F=22.756, P<0.01). ALC in HNO group and LNO group were higher than that in MV group (F=3.965, P<0.05). The W/D ratio of lung in MV group was higher than that in HNO group, and the W/D rate in HNO group was higher than that in LNO group (F=11.740, P<0.01). (4) Lung injury score in HNO group and LNO group was higher than that in MV group, but without significant difference. CONCLUSION: iNO can reduce lung edema by increasing ALC and improving alveolar permeability, and the LNO may be more effective than HNO in treatment of early acute lung injury induced by endotoxin.

[Effects of ventilation in prone position combined with recruitment maneuver on lung injury in dogs with acute respiratory distress syndrome].

OBJECTIVE: To evaluate protective effect and its mechanism of prone position ventilation (PPV) combined with recruitment maneuver (RM) as a lung protective ventilation strategy on oleic acid-induced acute respiratory distress syndrome (ARDS) in dogs. METHODS: Twenty-four oleic acid-induced ARDS dogs were ventilated with volume controlled ventilation (VCV): 16 cm H2O (1 cm H2O=0.098 kPa) of positive end-expiratory pressure (PEEP) and 10 ml/kg of tidal volume (VT). All dogs were randomly divided by random digit table into four groups: supine position (SP group), prone position (PP group), supine position+RM (SPRM group), and prone position+RM (PPRM group, 6 in each group), and ventilated by VCV for 4 hours and then sacrificed by exsanguination. The serum levels of inflammatory mediators were measured respectively at 0.5, 2 and 4 hours. After they were sacrificed, the levels of cytokines in left lung tissue homogenate were measured. The wet/dry weight ratio of right lung was determined and histological sections of the lungs were prepared and examined. RESULTS: (1) At 4 hours, interleukin-8 (IL-8) in serum in the SPRM group was significantly higher than in other three groups (all P<0.05), tumor necrosis factor-alpha (TNF-alpha) in serum in the SPRM group was significantly higher than in the PP group and the PPRM group (all P<0.05). (2) IL-8 in lung tissue homogenate of the dorsal aspect of the lung in the SP group was higher than in the PP group and the PPRM group (both P<0.05). TNF-alpha in lung tissue homogenate at the dorsal aspect of the lung in the SPRM group was higher than in the PP group and the PPRM group (both P<0.05). (3) Wet/dry weight ratio of right lung in the PP group and the PPRM group were significantly lower than that in the SP group and the SPRM group (all P<0.05). (4)Pathology score of lung tissue at the dorsal aspect of the lung in the PP group and PPRM group was significantly lower than in the SP group and the SPRM group (all P<0.05). CONCLUSION: Protective ventilation strategy combined with RM is safer in prone position than supine position, and it alleviates lung injury in dog with ARDS.

[The effects of different ventilatory modes and spontaneous breathing after recruitment maneuver in acute respiratory distress syndrome. Experiment with dogs].

OBJECTIVE: To investigate the role of different ventilatory modes and spontaneous breathing (SB) in prevention of derecruitment in acute respiratory distress syndrome (ARDS). METHODS: Eighteen dog ARDS models were established by injection of oleic acid into the central vein and ventilated with volume controlled ventilation (VCV,) with the positive end expiratory pressure (PEEP) of 16 cm H(2)O, tidal volume (V(T)) of 10 ml/kg, and respiratory rate (RR) of 30 bpm, and the steady state in this mode was defined as baseline (0 min). After the baseline state was reached, all dogs accepted recruitment maneuver (RM) in pressure controlled ventilation (PCV) mode at the level of 15 cm H(2)O and PEEP of 35 cm H(2)O for 1 min, and then assigned into three groups and ventilated for 4 hs: VCV group (VCV with V(T) of 15 ml/kg), PCV group in which the peak inspiratory airway pressure was adjusted for keeping 15 ml/kg of V(T), and SB grouping which PCV with SB activity and inspiratory airway pressure were adjusted for keeping 15 ml/kg of V(T). PEEP of 10 cm H(2)O, RR of 20 bpm, and inspiratory/expiratory ratio of 1/2 were kept for all animals. Four hours later the dogs were killed and their lungs were taken out. RESULTS: (1) The lower inflection points were identified as 16.1 +/- 1.9, 17.4 +/- 1.5, and 17.1 +/- 1.6 cm H(2)O for the VCV, PCV, and SB group respectively. (2) After RM, the PaO(2) levels of the PCV and SB groups were kept higher than baseline, but the PaO(2) level was as same as that in the baseline state in the VCV group. Compared with the VCV group, higher PaO(2) the PaO(2) level 30 min after RM in the SB group was found (P < 0.05). The intrapulmonary shunt 5 min, 30 min and 1 hr after RM in the SB group were all lower than those in the VCP group, however, not significantly (P = 0.077, 0.058, 0.076). (3) Compared with baseline levels, the plateau pressure and mean airway pressure in all animals were decreased significantly after RM. The plateau pressure in the SB group was significantly lower than that in the VCV group (P < 0.05). CONCLUSION: PCV with spontaneous breathing activity can offset the effect of antiderecruitment for lower PEEP; it would be more safe and effective than VCV.