ABSTRACT
Objective To investigate the effects of exogenous pulmonary surfactant(PS)on the inflammatory response in rats with ventilator-induced lung injury(VILI).Methods Twenty-eight adult male Wistar rats weighing 310-388 g were randomly divided into 4 groups(n =7 each):normal control group(group C),group VILI,group PS and air control group(group A).VILI was produced by high-pressure ventilation(HPV)with peak inspiratory pressure(PIP)40 cm H2 O,respiratory rate(RR)20 hpm and without positive end-expiratory pressure(PEEP)for 20 min.The rats were sacrificed by exsanguination immediately after anesthesia and after VILI in groups C and VILI,respectively.In groups PS and A,PS 100 mg/kg(50 mg/ml)and the equal volume of air were injected into the trachea via the airway after the tracheal edema fluid was removed respectively,and the rats were mechanically ventilated(Vr 10 ml/kg,RR 45 bpm and PEEP 7.5 cmH2O)for 120 min and then sacrificed by exsanguination.The blood samples were taken from femoral artery for determination of the plasma levels of IL-6,IL-10,MIP-2 and TNF-α by ELISA.The tracheal edema fluid was collected to determine the protein concentration by Bradford method.The lungs were removed for microscopic examination and the number of neutrophils was counted under microscope.Results There was no significant difference in the plasma levels of TNF-α among the four groups(P ＞ 0.05).Compared to group C,the plasma levels of MIP-2,IL-10 and IL-6 were significantly increased and the number of neutrophils was significantly enlarged in group VILI(P ＜ 0.05).The number of neutrophils was significantly smaller in group PS than in group A(P ＜ 0.05).There was no significant difference in the plasma levels of MIP-2,IL-10 and IL-6 between groups PS and A(P ＞ 0.05).The inflammatory damage in lung tissues was observed obviously in groups VILI,A and PS.Conclusion When exogenous PS is used to treat the rats with VILI,PS reduces neutrophil recruitment,but can not inhibit the release of inflammatory cytokines.
ABSTRACT
Objectlve To investigate the effects of different ventilation modes on the efficacy of exogenous pulmonary surfactant(PS)for the treatment of rats with ventilator-induced lung injury(VILI).Methods Forty-two male Wistar rats weighing 310-356 g were randomly divided into 6 groups(n=7 each):group CVT6,group SVT6,group CVT10,group SVT10,group CVT14 and group SVT14.The tidal volume(VT)was set at 6,10 and 14 ml/kg respectively and the respiratory rate(RR) was 75,45 and 32 bpm respectively.The animals were anesthetized with intraperitoneal 3% Pentobarbital 50 mg/kg,then tracheostomized and intubated.VILI model was induced by high-pressure ventilation (HPV) with peak inspimtory pressure (PIP) 40 cm H2O and without positive end-expiratory pressure (PEEP).The air was injected into the trachea via the airway at the end ofexpiration before HPV (T0,baseline value) and 15-25 min of HPV,the airway pressure monitored and the lung compliance(C) calculated.When C was decreased to half of the baseline value,PEEP was increased to 7.5 cm H20.After the tracheal edema fluid was removed,the PS 100 mg/kg was immediately injected into the trachea in group SVT6,SVT10 and SVT14.The equal volume of air was injected into the trachea in group CVT6,CVT10 and CVr14 instead of PS.Then the rats in different groups were ventilated with the corresponding ventilation modes.MAP was monitored and blood samples were token from femoral artery for blood gas analysis at T0, 5 min after HPV (T1 ), and 15, 30, 60, 90, 120 min (T2-6) after administration of PS. The tracheal edema fluid was collected at T1 and T6.The rats were killed at T6 and the lung tissues taken for microscopic examination. Results With the same ventilation mode, the VILI was significantly alleviated after administration of PS. With different ventilation modes,the lung injury was significantly reduced in group SVT 10 compared with the other groups. Conclusion The efficacy of PS for the treatment of rats with VILI is good using the ventilation strategy with VT of 10 ml/kg and RR of 45 bpm.
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Objective To study the diagnostic value of thin-slice reconstruction of multi-slice spiral CT(MSCT) in solitary pulmonary nodule(SPN).Methods 55 cases of SPN confirmed by pathology were analysed retrospectively.All cases underwent chest MSCT scan and thin-slice reconstruction images were obtained at 10.0 mm,5.0 mm,2.5 mm and 1.25 mm thickness.The detecting rate of CT findings of SPN on different thickness CT images was evaluated,and the effect of thin-slice images and traditional CT scan in diagnosing benign and malignant pulmonary nodules ?2 test.Results(1)In detecting rate of CT findings of SPN,the thin-slice(1.25 mm) reconstruction was better than traditional CT(P
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Objective To evaluate mini-dose pre-injection test in the use of contrast-enhanced magnetic resonance angiography (CEMRA), and to inspect the possibility of contrast medium peak-time prediction by age, body weight and heart rate.Methods The data from mini-dose pre-injection test of contrast medium before vertebral artery CEMRA were retrospectively reviewed in 55 patients. The linear correlation and regression of the data including age, body weight, heart rate, and the reaching-time, peak-value-time, duration and peak-value-signal of contrast medium was performed by using SPSS software.Results The age (n=55, =62 years old, M=59 years old), body weight (n=55, = 63 kg), heart rate (n=40, =73 beats per minute), peak-value-time (n=55,=17.5 seconds), peak signal intensity (n=55,=472), and duration of contrast (n=49,=10.35 seconds)were analyzed. No statistically significant correlation existed between peak-value-time of contrast medium and the age (r=0.231, t=1.728, P=0.090), body weight (r=0.118, t=0.865, P=0.392), and heart rate (r= -0.046, t=-0.284, P=0.776). The peak-value-time correlated negatively with peak signal intensity (r=-0.322, t=-2.56, P=0.016)and positively with duration of contrast (r=0.658, t=5.99, P=0.000). The peak signal intensity was negatively correlated with body weight(r=-0.356, t=-2.77, P=0.008). The linear regression analysis show b=-0.284, t=-2.285, P=0.026 between peak-value-signal and peak-value-time, b=-0.322, t=2.590, P=0.012 between peak-value-signal and body weight.Conclusion Mini-dose pre-injection test was more helpful to adjust the rate of contrast medium injection and determine the time delay during scanning. But the prediction of contrast peak-time based on age, body weight and heart rate was unreliable.
