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Objective To investigate the effect of high-frequency oscillatory ventilation (HFOV) on inflammatory responses in lung tissues of dogs with severe acute respiratory distress syndrome (ARDS).Methods Healthy mongrel dogs of both sexes,weighing 13.7-16.2 kg,in which severe ARDS was induced by intravenous infusion of the mixture of oleic acid 0.2 ml/kg and autologous blood (equal to the volume of oleic acid).Twenty-four dogs with severe ARDS were randomly divided into 4 groups (n=6 each) using a random number table:conventional mechanical ventilation with low tidal volume group (group CMV),HFOV-9 Hz group,HFOV-12 Hz group and HFOV-15 Hz group.In HFOV-9 Hz,HFOV-12 Hz and HFOV-15 Hz groups,the frequency was 9,12,and 15 Hz,respectively,mean airway pressure 20 cmH2O,oscillation pressure 70 cmH2O,and inspired oxygen fraction ratio 1.0.In group CMV,the animals were mechanically ventilated in volume-controlled mode,with positive end-expiratory pressure 5 cmH2O,tidal volume 6 ml/kg,respiratory rate 30 breaths/min,inspiratory/expiratory ratio 1:2,and inspired oxygen fraction ratio 1.0.At 4 h of ventilation,the animals were sacrificed,and lungs were removed for determination of wet/dry weight (W/D) ratio,contents of tumor necrosis factor-alpha (TNF-α),interleukin-6 (IL-6) and IL-10 (by enzyme-linked immunosorbent assay),and expression of vascular endothelial (VE)-Cadherin (by Western blot) and for microscopic examination.Lung injury scores were assessed.Results Compared with group CMV,the lung injury scores,W/D ratio,and contents of TNF-α and IL-6 were significantly decreased,the content of IL-10 was significantly increased,and the expression of VE-Cadherin was significantly up-regulated in the other three groups (P＜0.05).Compared with group HFOV-9Hz,the lung injury scores,W/D ratio and contents of TNF-α and IL-6 were significantly decreased,the content of IL-10 was significantly increased,and the expression of VE-Cadherin was significantly up-regulated in group HFOV-15 Hz,and the content of IL-6 was significantly decreased in group HFOV-12 Hz (P＜0.05).Conclusion HFOV can significantly inhibit inflammatory responses in lung tissues of dogs with severe ARDS as compared with mechanical ventilation with low tidal volume,which may be involved in the mechanism of lung-protective ventilation effect.
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Objective To explore the therapeutic potential and mechanism of stem cells mobilized by granulocyte colony-stimulating factor (G-CSF) and AMD3100 to repair global cerebral ischemia injuries in a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR).Methods Cardiac arrest was induced by asphyxia.Fifty-six SD rats were randomly assigned into four groups:G-CSF group,G-CSF + AMD3100 group,CPR control group and sham operated group.The animals were sacrificed at 3d and 6d after CPR respectively.The neurological status and morphological changes of damaged cerebrum,the apoptosis of nerve cells and vascular endothelial growth factor (VEGF) expressed in brain tissue and capillary density in hippocampus and temporal lobe cortex were measured and analyzed by means of neurological deficit score (NDS),adhesive tape removal test (TRT),ELISA,MRI and immunofluorescence.Results NDS in G-CSF + AMD3100 group (61.4 ± 10.7) was significantly higher than that in CPR control group (49.9 ± 10.4) at 3 d after CPR (P ＜0.05).And less time consumption for TRT found in G-CSF + AMD3100 group (85.5 ±28.9) s rather than was in CPR control group (148.1 ± 23.8) s and G-CSF group (118.5 ± 30.4) s (P ＜ 0.05).The severity of cerebral injury assessed by MRI was significantly milder at both 3 d and 6 d in the two stem cell mobilization groups.The apoptosis rate of nerve cells in G-CSF + AMD3100 group (0.23 ± 0.06) was significantly lower than that in G-CSF group (0.34 ±0.08) at 3 d after CPR,and that in both stem cell mobilization groups was lower than that in CPR control group (0.44 ± 0.09) (P ＜ 0.05).At 3 d and 6 d after CPR,the levels of VEGF in brain tissue were (106.2 ±23.3) pg/mL and (79.9 ± 18.4) pg/mL in G-CSF + AMD3100 group,and were (50.6 ± 13.7) pg/mL and (73.9 ± 16.6) pg/mL in G-CSF group,which were both significantly higher than that in CPR control group (23.1 ± 10.2) pg/mL and (36.2 ± 12.8) pg/mL (P ＜0.05).At 3 d after CPR,the cerebral capillary density (351.8 ±67.9) branches in every high power field (A/HPF) was significantly higher in G-CSF + AMD3100 group than that (301.4 ± 77.3) A/HPF in G-CSF group and (250.4 ± 48.0) A/HPF in CPR control group (P ＜ 0.05).The cerebral capillary density in G-CSF group elevated to (348.4 ±76.7) A/HPF at 6 d after CPR which was significantly higher than that at 3 d (P ＜0.05),and there was no difference between that at 3 d and 6 d in G-CSF + AMD3100 group.Conclusions The mobilization stem cells improve the impaired neurological function.The increased expression of VEGF in brain tissue,the neo-vascularization promoted by the mobilized stem cells and the inhibition of nerve cell apoptosis may be associated with the protective effects of the stem cell mobilization.
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Objective To approach the effect of Shenfu injection (SFI) and conventional early goal-directed therapy (EGDT) on organ functions and outcomes of septic shock patients. Methods Eighty-four cases conformed to the criteria for the diagnosis of septic shock admitted to Department of Critical Care Medicine of Xuzhou Central Hospital were randomly divided into conventional treatment group (42 cases), and SFI treatment group (42 cases). Conventional treatment was given in the two groups;in SFI treatment group, SFI 100 mL was additionally given by trace continuous intravenous pump 20 mL/h, twice daily for 7 days. Before and after treatment for 1, 6, 12, 24, 48, 72 hours, the levels of hemodynamic status, lactic acid and dosage of vasoactive drugs used, organ function, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, sequential organ failure assessment (SOFA) score, the time of weaning from ventilator, the length of stay in intensive care unit (ICU), time without organ failure and 28-day mortality rate were observed. Results Compared with those before treatment, after treatment in the two groups, the mean arterial pressure (MAP), cardiac index (CI) and systemic vascular resistance index (SVRI) were increased, while the levels of heart rate (HR) and lactate were decreased (all P0.05). Compared with that before treatment, in the conventional treatment group after treatment for 1 and 3 days, gamma glutamyl transpeptidase (GGT) was increased, on the 5th day it began to decrease, reaching its minimum on the 7th day (U/L:26.75±16.74 vs. 46.96±25.85);while in SFI treatment group, GGT was increased after treatment for 1 day, on 3rd day it began to decrease, reaching its lowest level on the 7th day (U/L:22.41±17.87 vs. 51.23±27.74);aspartate aminotransferase (AST), total bilirubin (TBil), oxygenation index (PaO2/FiO2) were increased after the treatment for 1, 3, 5, 7 days, and blood urea nitrogen (BUN), creatinine (Cr) were decreased at different time points after treatment. In the conventional treatment group, the precursor protein (PA) was decreased after treatment for 1, 3, 5 days, on the 7th day it was increased (mg/L:134.20±63.44 vs. 115.70±45.96);while in SFI treatment group, after the treatment for 1 days and 3 days, it was decreased, on the 5th day it was increased, reaching its highest level on the 7th day (mg/L:145.40±59.75 vs. 108.20±54.34). Compared with those before treatment, after treatment for 1, 3, 5, 7 days, APACHEⅡscore and SOFA score were decreased in the two groups, but there was no statistically significant difference in APACHEⅡscore between the two groups, in SFI treatment group after treatment for 3 days, SOFA score was significantly lower than that of the conventional treatment group (6.31±3.86 vs. 7.14±4.03, P0.05). Conclusion The combined use of SFI and EGDT can improve hemodynamics, reduce damage to vital organs, and shorten the times for ventilation and stay in ICU in septic shock patients.
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Objective To explore the use of pulse indication contour cardiac output (PiCCO) as a guidance for fluid resuscitation and vasopressors employment in patients with septic shock in order to find out the efficacy of this resuscitation strategy in the respect of outcome of patients. Mtthod A total of 30 patients with septic shock were treated with the EDGT fluid treatment protocol as the conventional treatment group from December 2006 to June 2008; and another 26 patients were given fluid treatment under the guidance of PiCCO as PiCCO group from July 2008 to October 2009. Exclusion criteria included patients with history of heart and lung diseases, and liver and kidney dysfunction. The mean arterial blood pressure was maintained above or equal to 65mmHg in PiCCO group,and fluid resuscitation was concluded when global end-diastolic volume index reached 600～750 mL·-2 with the stroke volume variation in ＜ 10% and without auricular fibrillation. Nor-epinephrine was administrated to adiust the systemic peripheral vascular resistance index during 1300～1500 d·s·cm-5·m-2.Dobutamine was empoyed when global ejection fraction was compromised. The options of liquid and diuretics depend upon the presence d extra-vascular lung water. Central venous oxygen saturation and the level of lactate were observed 6hours after resuscitation. The liquid equilibrium for 3 days and the dosage of vasopressors were also recorded. The rate of survival, the time taken for weaning from mechanical ventilation, the days of ICU stay and rate of intact organ function within 28 days were compared between two groups. Results The demphics of patients of two goups were similar. There were no significant difference between PiCCO and the conventional group in values of central venous oxygen saturation and lactate 6 hours after admission to ICU (P ＞ 0.05). And 6 h and 1d after fluid resuscitation, the dosages of dobutamine and the dosages of nor-epinephrine used in PiCCO group were significantly higher than those in conventional group in which the dosages of dobutamine in two groups were [(145.4±24.5)mg vs. (104.2 ± 46.3) mg and (330.2 ± 30.3) mg vs. (202.4 ± 40.3) mg], respectively, and the dosages of nor-epinephrine [(14.5±3.8) mgvs. (10.2±5.6) mgand (38.2±4.2) rng vs.(20.1±6.2) mg], respectively. However, the dosages of vasopressors were similar between two groups 2 d and 3 d later. The amounts of liquid administered to get equilibrium in 6 h and the 3 d in PiCCO group were significantly less than those in conventional group [(2121±578) mL vs. (2910±987) mL and (3845±435) mL vs. (4545 ± 765) mL and (2467±510) mLvs. (2867±618) mL and (951±332) mLvs. (1472±533) mL], respectively. The days required to get free from mechanical ventilation within 28d were significantly longer in PiCGO group[(19.7 ± 8.3) d vs.(15.1±9.1) d], but the days of ICU stay were significantly shorter in PiCCO group [(7.5 ± 3.5) d vs. (9.5±3.2) d] (P＜0.05). The rates of survival and days free from organ failure within 28 days of two groups were similar(P＞0.05). Conclusions When the early fluid management guided with PiCCO in septic shock patients,the fluid management can be implement more safely and precisely. It can shorten the days of ICU stay and days of mechanical ventilation support with avoidance of fluid resuscitation.
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Objective To explore the effect of different positive end expiratory pressures (PEEP) on oxygen delivery (DO2) after recruitment maneuvers (RM) in dogs with acute respiratory distress syndrome (ARDS). Method After ARDS models established in 15 dogs by oleic acid, static P-V (pressure-volume) curves were determined by low flow technique. Lower inflection point (LIP) was set by two-way linear regression methods. RM was operated with the pressure control method. ARDS dog models were randomly divided into three groups, namely PEEP 8 cmH2O group (group A), 12 cmH2O group (group B) and 16cmH2O group (group C) after RM (equivalent to pressure at4 cmH2O under LIP, 4 cmH2O near LIP, and 4 cmH2O above LIP, respectively). Hemodynamics and arterial blood gas analysis were monitored before RM, 0, 5, 10 and 15 min after RM. The recruited volume was measured by P-V curve method 15 min after RM and respiratory mechanics was also observed at the same time. Then DO2 was calculated. The quantitative variables were summarized as the mean and SD. The t-test was used to compare continuous variables between the two independent samples. One-way analysis of variance was used to compare variables among three groups. The level of significance was set at P＜0.05 for all the tests. Results In group A, the levels of PaO2 were significantly reduced 5 min, 10 min and 15 min after RM[(257 ± 23 )mmHg, (253±21)mmHg, and (255±19)mmHg] compared with PaO2 at 0 min [(322 ± 20) mmHg] (P＜0.05).But in group B and group C, the levels of PaO2 5 min, 10 min and 15 min after RM were not lower than level of PaO2 at 0 min after RM (P＞0.05 ). The levels of PaO2 in groups B and C were higher than that in group A at the same time (P＜0.05). The recruited volume distinctly increased with PEEP levels escalated [(50±12 ) mL, (124 ±15) mL, and ( 157 ±10)mL](P＜0.05). However, the increment in the recruited volume from PEEP 8 cmH2O to 12 cmH2O was dramatically greater than that from PEEP 12 cmH2O to 16 cmH2O.There was no significant difference in static compliance between group A and B [(14.3 ± 2.2) mL/cmH2O vs. (17.2±1.4)mL/cmH2O] (P ＞ 0.05 ). But compared with groups A and B, the static compliance in the group C significantly reduced(10.5 ± 0.9) mL/cmH2O ( P ＜ 0.05 ). The ratios of DO2 after RM to DO2 before RM were different at different levels of PEEP. The levels of DO2 after RM[( 1.15 ± 0. 11 ),( 1. 14 ± 0.12), ( 1.14 ± 0. 12) and ( 1.16 ± 0.11 )] increased more greatly than that before RM ( 1.00 ±0.09) in the group B (P ＜ 0.05 ). It did not occurred in the groups A and C. Conclusions The PEEP 12 cmH2O set at near the LIP after RM could be the optimal PEEP. Not only can it improve DO2 and the static compliance, but also maintain oxygenation and the recruited volume after RM.
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ObjectiveTo observe the effects of norepinephrine and dobutamine (NE+Dobu) on hemodynamics, tissue perfusion and oxygen metabolism in elderly patients with septic shock at different levels of mean arterial pressure (MAP). MethodsAfter aggressive fluid resuscitation,norepinephrine and dobutamine were administered in 18 elderly patients with septic shock to correct hypotension. The rate of dobutamine infusion was 5 ug. kg<'-1>. min<'-1> Norepinephrine was titrated to maintain MAP at levels of 65 mm Hg, 75 mm Hg and 85 mmHg. Four hours later, the changes of hemodynamics, oxygenation index, blood lactate, renal function and gastric pCO<,2> at every MAP level were observed. ResultsThere were no significant differences in heart rate (HR), pulmonary arterial wedge pressure (PAWP), volume of oxygen (VO<,2>), Blood lactate, pH value, △pCO<'2> and creatinine clearance rate (CCr) among the MAP levels of 65 mm Hg, 75 mm Hg and 85 mm Hg ( all P>0.05). Compared with MAP 65 mm Hg, cardiac index (CI), systemic vascular resistance index (SVRI), oxygen delivery over oxygen extraction ratio were obviously higher at MAP 75 mm Hg and 85 mm Hg [4.7±0.6, 5.1±0.7 vs. 4.0±0.6; 1162±278, 1276±319 vs. 1011±225; (697±53) ml. min<'1>. m<'2>,(711±68)ml. min<'-1>. m<'2> vs. (634±70) ml · min<'-1> · m<'2>; (0.28±0.02)%,(0.27±0.02)% vs. (0.25±0.02) %, respectively, all P<0.05). The urinary output at MAP levels of 65 mm Hg, 75 mm Hg and 85 mm Hg were (98±43)ml/h, (91±54) ml/h and(74±49)ml/h repectively, and only the differences between MAP 75 mm Hg and MAP 65 mm Hg had statistical significance (P<0.05).ConclusionsAfter aggressive fluid resuscitation, hemodynamics and renal function are improved at MAP 75 mm Hg after administration of norepinephrine and dobutamine in elderly patients with septic shock. It should be considered that MAP is appropriately increased in elderly patients with septic shock.
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Objective To investigate the clinical effects, therapy safety and maintenance time of recruitment maneuvers (RM) combined with lung protective strategy in patients with acute respiratory distress syndrome (ARDS). Methods Thirty-two ventilated patients with ARDS underwent RM using a pressure of 30cmH_2O for 30s, without any sedatives and neuromuscular blocking agents. Results Compared with before RM, both oxhemoglobin saturation measured by pulse oximetry (SpO_2) and partial pressure of arterial oxygen (PaO_2) were significantly increased during one hour after applying RM. SpO_2 increased significantly within two hours after RM. The peak inspiratory pressures (PIP), heart rate (HR) and Pplateau inspiratory pressures (Pplate) had not significant difference between after and before RM, but respiratory system compliance (Crs) increased markedly in one hour after RM (P