1.The Clinical Value of Pulse Pressure Variation to Monitor the Fluid Responsiveness and Effects of PEEP in Ventilated Patients with Acute Lung Injury
Qin GU ; Ning LIU ; Jianfeng YU
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):388-391
Objective To investigate whether pulse pressure variation (△PP) reflect the effects of PEEP and fluid resuscitation (FR) on hemodynamic effects.Methods Twenty critical patients with acute lung injury was ventilated with volume control (VT =8 mL/kg,Ti/Te = 1: 2) ,and PaCO2 was kept at 35 to 45 mm Hg.PEEP was setted as 5 cm H2O and 15 cm H2O in randomized order.Hemodynamic parameters including cardiac index, pulse pressure, central venous pressure, etc.were monitered by PiCCO system.Measurements were performed after the application of 5 cm H2O PEEP (PEEPs group)and 15 cm H2O PEEP (PEEP15 group) respectively.When the PEEP-induced decrease in cardiac index (CI) was > 10%, measurements were also performed after fluid resuscitation.Results Compared with PEEPs group, CI was decreased significantly in PEEP15 group(P < 0.05), and APP was increased significantly (P < 0.05).In 14 patients whose PEEP-induced decrease in CI was > 10%, fluid resuscitation increased CI from (3.01±0.57)L · min-1· m-1to (3.62±0.68)L · min-1 · m-2(P<0.01),and decreased △PP from (17±3)% to (10±2) % (P < 0.01).PEEP15-induced decrease in CI was correlated negatively with APP on PEEP5 (r =-0.91,P < 0.01) and with the PEEP15-induced increase in △PP (r =-0.79, P < 0.01).FR-induced changes in CI correlated with APP before FR (r = 0.96, P < 0.01) and with the FR-induced decrease in APP (r =-0.95, P < 0.01).Conclusions In ventilated patients with ALI, △PP may be a simple and useful parameter in predicting and assessing the hemodynamic effects of PEEP and FR.
2.Effect of Paroxetine on Sleep Apneas in Sprague-Dawley Rats
Yao WANG ; Guangfa WANG ; Cheng ZHANG
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):384-387
Objective To evaluate the effects of selective serotonin reuptake inhibitors (SSRIs) on sleep apneas in Sprague-Dawley (SD) rats.Methods Thirty adult male SD rats were randomly divided into two groups (15 rats in each group).The treatment group and the control group were injected intraperitoneally with paroxetine (10 mg · kg-1·d-1) and sterile distilled water (2 mL · kg-1 · d-1) for 7 days respectively.Parameters about sleep apnea and sleep structure were measured before and after the treatment.Results In the treatment group, there was a significant reduction of apnea index (AI) from (12.4±3.7) times/hour to (7.4±2.2) tmes/hour (P = 0.000).Both post sigh apnea index (PSAI) and spontaneous apnea index (SPAI) were decreased significantly (P = 0.000 and 0.021 respectively) in non-rapid eye movement (NREM) sleep, but not in REM sleep.REM sleep was reduced from 8.6% to 8.0% (P = 0.013) and its latency was increased from (54.1±48.4) rain to (110.9±43.4) min (P = 0.001) in the treatment group,as well as the sleep-onset latency [from (20.7±9.1) rain to (30.0±15.7) rain, P = 0.038].Conclusion Paroxetine can reduce sleep apneas in SD rats during NREM sleep.Its effects on sleep structure include reducing REM time,increasing REM latency and sleep-onset latency.
3.A Novel Rabbit Carotid Body and Common Carotid Artery Model in Vivo for the Simulation of Various Intermittent and Continuous Hypoxia Modes
Jing FENG ; Linyang CUI ; Baoyuan CHEN ; Meinan GUO ; Jie CAO ; Bei SUN
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):380-383
Objective To develope a novel rabbit carotid body and carotid common artery model in vivo for the simulation of various intermittent hypoxia (IH) intensities, IH durations, IH reoxygenation (ROX) durations and continuous hypoxia (CH) modes.Methods Forty-five adult New Zealand rabbits (2.5~3.0 kg) were anesthetized while spontaneous breathing kept intact.The tissue surrounding the fight earetid common artery and carotid sinus nerve (CSN) were cleared and "single" chemoreceptor bundle of the CSN was revealed.Then suction electrodes were placed and CSN afferent activity was monitored and recorded carefully.The fight common carotid artery was exposed, cannulated to distal part and its proximal part was ligated.Preparations were challenged by changing the PO2 of the gas mixture equilibrating the perfusate.Alternatively perfusion (2 mL/min) of equilibrated porfusate bubbled with normoxia or hypoxia gas mixtures formed IH/ROX cycles in carotid common artery,simulating the pattern of hypoxic episodes seen in obstructive sleep apnea syndrome (OSAS), or with continuously perfusing hypoxia perfusate to form CH modes.All the perfusing procedures were regulated by a customized computer-controlled set and monitored using O2 gas analyzer.After the systematic exposures, carotid body, carotid common artery part distal to cannula,and carotid bifurcation were harvested as samples.Results The frequencies and average amplitudes of CSN chemoreceptor bundles afferent activities with normoxia peffusion were (0.17±0.03) impulse/s and (46.2±4.4) μV, and with hypoxia perfusion were (0.6±0.09) impulse/s and (87.4±6.6) μV, respectively.PO2 was (139±1.5) nun Hg in normoxia perfusate and (35.2±1.3) mm Hg in hypoxia perfusate.Conclusion This new carotid body and carotid common artery model is a valuable tool to study neurological and biochemical changes in various IH and CH modes.
4.Effects of Continuous Positive Airway Pressure on Serum Inflammatory Factors in Coronary Heart Disease Patients Complicated with Obstructive Sleep Apnea-Hypopnea Syndrome
Ke HU ; Yan JIANG ; Huijun FAN ; Jingya HE
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):376-379
Objective To investigate the changes and significance of serum inflammatory factors in coronary heart disease (CHD) patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) ,and the treatment effects of continuous positive airway pressure (CPAP).Methods A total of 76 CHD patients in Renmin Hospital of Wuhan University from October 2007 to October 2008 were enrolled.Polysomnography (PSG) was performed in these CHD patients to identify if they were complicated by OSAHS.The levels of inflammatory factors including TNF-α, IL-6, high sensitive C-reactive protein (hs-CRP) in serum were determined in the CHD patients and 23 normal subjects.The CHD patients with mederate-severe OSAHS (AHI≥ 15 episodes/hour) were treated by Auto-CPAP for 3 months and all parameters above were measured again.Results There were 41/76 (53.9%) of CHD patients had mederate-severe OSAHS and were treated with CPAP.The levels of TNF-ct,IL-6 and hs-CRP were significantly higher in the CHD patients than those in the normal controls (all P <0.01) ,and were significantly higher in moderate-severe OSAHS patients than those in the non-OSAHS CHD patients.Auto-CPAP ventilation significantly decreased the levels of inflammatory factors in the CHD patients with moderate-severe OSAHS.Conclusions An obvious proinflammatory state is detected in CHD patients ,and is aggravated with OSAHS.CPAP is a useful treatment for CHD patients with mediate to severe OSAHS.
5.Relationships Between Health-Related Quality of Life and Social Support in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome
Kai SUN ; Zongan LIANG ; Maoyun WANG ; Fei LEI
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):371-375
Objective To study the relationships among health-related quality of life(HRQL), social support, excessive daytime sleepiness (EDS) and PSG parameters in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).Methods Eighty-five patients were recruited who were diagnosed as OSAHS by overnight po]ysomnography from August 2007 through November 2007 in West China Hospital.The Calgary sleep apnea quality of life index (SAQLI) was used for HRQL, social support rating scale (SSRS) was used for social support,and Epworth sleepiness scale(ESS) was used for EDS.The Pearson linear correlation and stepwise multiple regression analysis were used to analyze the correlation among SAQLI, SSRS, ESS, and PSG.Results The SAQLI was correlated with SSRS score (r = 0.402, P < 0.01) ; ESS score (r =-0.505 ,P <0.01) ; apnea-hypopnea index (AHI) (r =-0.269,P <0.05) and lowest artery oxygen saturation (ISaO2) (r = 0.226, P < 0.05).Stepwise muhiple regression analysis determined two variables,the SSRS and ESS score,as independent factors for predicting the total score of SAQLI which accounted for 37.3% of the total variance in the total score on SAQLI (R2 = 0.373, P < 0.001).Conclusions The HRQL of patients with OSAHS was correlated with the SSRS score, ESS score and PSG parameters.The former two were the more important factors to affect the HRQL of patients with OSAHS.
6.The Inhibitory Mechanism of Imatinib Mesylate on Bleomycin-Induced Pulmonary Fibrosis in Mice
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):365-370
Objective To explore the inhibitory mechanism of Imatinib mesylate on pulmonary fibrosis induced by bleomycin in mice.Methods A total of 120 C57BL/6 mice were randomly divided into four groups,ie, a control group, a model group, a dexamethasone group, and an Imatinib group.The model of pulmonary fibrosis was established by a single intratracheal instillation of bleomycin in the rats.Then dexamethasone or Imatinib were given intraperitoneally respectively.On day 7,14,21 after the treatment, 10 mice of each group were sacrificed respectively.The expressions of TGF-β1 and α-SMA in lung tissue were analyzed by immunohistochemistry.The mRNA expression of TGF-β1 was measured by RT-PCR.Results The expressions of TGF-β1 and α-SMA in lung tissue at each time point were significantly increased in the model group compared with the control group.And the expressions were obviously decreased in the dexamethasone group and the lmatinib group compared with the model group, with no significant differences between the two treatment groups.The expression of TGF-β1 was positively correlated with the α-SMA expression (r = 0.251, P < 0.05).Conclusion The inhibitory effect of Imatinib on pulmonary fibrosis may be related to the inhibition of TGF-β1 and α-SMA expressions.
7.Effects of Cigarette Smoke Extract on the Proliferation and Secretion of Hydrogen Peroxide in Human Lung Fibroblasts Induced by Transforming Growth Factor-β1
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):360-364
Objective To observe the effects of cigarette smoke extract (CSE) on the proliferation and secretion of hydrogen peroxide (H2O2) in human lung fibroblasts (HLFs) induced by transforming growth faetor-β1(TGF-β1).Methods Cultured HLFs were divided into a normal group and a model group induced by TGF-β1 (5 ng/mL),then intervened with CSE at different concentrations (0% ,2.5% ,5%, 10%, respectively).Brdu ELISA assay was used to detect cell proliferation.H2O2release from cultured cells was assayed using a fluorimetric method.Cellular localization of H2O2 and expression of α-SMA were performed using a fluorescent-labeling strategy.Results TGF-β1 stimulated group showed positive expression of α-SMA, implying TGF-β1 had induced fibroblasts to differentiate into myofibroblasts.In TGF-β1 stimulated group,2.5% and 5% CSE promoted cell proliferation (P < 0.01 or 0.05), while 10% CSE inhibited cell proliferation (P < 0.01).In the normal group, both low and high concentration of CSE inhibited cell proliferation (P < 0.01 or P < 0.05), and the inhibition effect was dose-dependent.HLF induced by TGF-β1 generated low constitutive levels of extracellular H2O2 that was markedly enhanced by CSE treatment (P < 0.01).Pretreatment with DPI, an inhibitor of NADPH oxidase, abolished secretion of H2O2.Cellular localization of H2O2 by a fluorescent-labeling strategy demonstrated that extracellular secretion of H2O2 is specific to the myofibroblast.Conclusions Low concentration of CSE can promote myofibroblast proliferation, and markedly increase extracellular secretion of H2O2.CSE possibly take part in the development and progress of idiopathic pulmonary fibrosis by increasing oxidative stress.
8.Clinicoradiologic Features of Acute Exacerbation of Idiopathic Pulmonary Fibrosis: Two Cases Report and Literature Review
Jinghong DAI ; Liyun MIAO ; Min CAO ; Hourong CAI
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):355-359
Objective To analyze the clinical presentations and radiological characteristics of acute exacerbation of idiopathic pulmonary fibrosis (IPF).Methods Clinical and radiological data of 2 patients with acute exacerbation of IPF from April 2006 to July 2008 were retrospectively analyzed and literatures were reviewed.Results Both patients were senior male patients over 60 years old.Dyspnea, cough and inspiratory crackles were the major symptoms and signs.Two patients were experiencing an exacerbation of dyspnea for one week and half of month,respectively.PaO2/FiO2 of both patients was less than 225 mm Hg.In both patients, high-resolution computed tomography (HRCT) scans at the exacerbation showed typical signs of IPF including peripheral predominant, basal predominant reticular abnormality, with honeycombing and traction bronchiectasis and bronchiolectasis,and newly developing alveolar opacity.HRCT scan showed peripheral area of ground-glass attenuation adjacent to subpleural honeycombing in one patient,and diffusely distributed ground-glass opacity in another patient.Two patients had received cortieosteroid treatment.For one patient, the symptoms improved, and ground-glass attenuation adjacent to subpleural honeycombing had almostly resolved.The other patient died of respiratory failure.Conclusions Some acute exacerbation in idiopatic pulmonary fibrosis can be idiopathic.The chnical presentations mainly include the worsening of dyspnea within short time.HRCT generally demonstrates new bilateral ground-glass abnormality with or without areas of consolidation, superimposed on typical changes of IPF.
9.Survey on Control Status and Knowledge Level about Disease in Asthmatic Patients in Region Level Cities of Shaanxi Province
Liqiang SONG ; Changgui WU ; Xiuzhen SUN ; Zhihong SHI ; Cailian HU ; Haidong LI ; Wenge LI ; Xiaopeng HE ; Heping ZHANG
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):351-354
Objective To evaluate the control status and knowledge level about disease in asthmatic patients in region level cities of Shaanxi province for effect appraisal of patient education.Methods Eight hospitals were selected from six region level cities, where questionnaire survey was completed in out-patients with asthma (≥ 14 years old).Results A total of 523 patients completed the questionnaire with a ratio of male to female of 1: 1.14,and an average age of (44.3±15.5) years old.The percentage of controlled, partly controlled and uncontrolled by self-evaluation was respectively 26.4%, 52.4% and 11.1%.48% insisted on using inhaled corticosteroids (ICS).The average score was 17.88±4.43 by asthma control test (ACT).The first three medicines used daily were ICS (26.6%), sustained-release theophyline (25.2%) and combination ICS/long-acting β2-agonists (21.8%).12.6% had no medicine and 5.2% used non-orthodox medicines.68.6% patients had omen before exacerbation, and those were sneezing, chest distress and cough.73.6% knew asthma is a disease of airway inilammatian,and 33.3% selected ICS as the leader medicine.Only 32.1% attended the lecture about asthma in hospitals and 85.0% longed for such education.Conclusions The control status and knowledge level about disease in asthmatic patients in cities still need to be improved in Shaanxi province, and too much work need to be done in order to realize the total control in all patients.
10.Single Nucleotide Polymorphisms in the 5'-Upstream Sequence of Chemokine Like Factor and their Association with Asthma
Wei ZHANG ; Quanying HE ; Guangfa WANG ; Hongshan ZHAO ; Chunhua CHI ; Yanru ZHAO ; Xuan DENG ; Li SU ; Yaoyao SUN ; Xiaodi WANG
Chinese Journal of Respiratory and Critical Care Medicine 2009;8(4):345-350
Objective To detect the single nucleotide polymorphisms (SNPs) in the upstream promoter region of chemokine like factor (CKLF) gene and analyze their possible associations with asthma and asthma-related phenotypes.Methods Direct Sequence of the 1553bp upstream promoter region of CKLF gene was performed in 245 Chinese Han human genomic DNAs (119 asthmatics and 126 controls).The frequencies of alleles, genotypes, and haplotypes were determined and the association of these SNPs with asthmawere further analyzed.Results Fournovel SNPs,SNP88 (T>C),SNPI96 (T>C),SNP568 (C> G) ,and SNP1047 (C > G) were found in the promoter region of CKLF.The frequency of rare allele was 0.168 (SNP88C), 0.168 (SNP196C), 0.352 (SNP568G) and 0.167 (SNP1047G), respectively.Haplotypes,their frequencies and the linkage disequilibrium coefficients between SNPs were constructed.Complete linkage disequilibrium (LDs) were observed between SNP88 and SNP196,SNP88 and SNP1047, as well as SNPI96 and SNP1047 ,respectively (D1 = 1.000,r2 = 1.000).SNP568 was in partial LD with the other three SNPs (r2 = 0.366).No association between asthma and the SNPs was observed.Conclusions Four SNPs in the regulatory region of CKLF in Chinese Han population were firstly identified.Although no significant correlation with asthma was revealed, the SNP and haplotype information is useful for other disease association studies in the future.