ABSTRACT
<p><b>OBJECTIVE</b>To establish a canine model of severe smoke inhalation injury on unilateral lung, in order to observe the pathomorphological changes in the injured lung within 24 postburn hours (PBHs).</p><p><b>METHODS</b>Twenty five mongrel dogs were employed in the study and randomized into 3 groups. The left lung was injured by inhaling smoke produced by burning sawdust with sparing the right lung with a breathing tube in 10 dogs in group A. A conventional model of smoke inhalation injury to bilateral lungs was reproduced in 8 dogs in group B, and dogs in group C not subjected to smoke inhalation served as controls. Hemodynamic changes, blood gas analysis and the pathophysiologic changes in the lungs were observed within 24 PBHs.</p><p><b>RESULTS</b>All of the dogs in groups A and C survived. Hemodynamic indices in the dogs in groups A and C remained stable without showing signs of systemic hypoxia. The arterial oxygen partial pressure in dogs of group A was 65 +/- 5 mm Hg, and the oxygen saturation in the mixed blood was 0.64 +/- 0.04 at 24 PBHs, and they were much lower than those in group C but higher than those in group B. The pathological changes in the injured side of the lungs in group A were similar to those in group B with high consistency, and the changes, though milder, could also be identified in the contralateral uninjured lung. Five dogs died in the group B within 24 hours after smoke inhalation and the survivors showed signs of multiple organ failure.</p><p><b>CONCLUSION</b>The canine model of acute severe unilateral pulmonary smoke inhalation injury was reproduced reliably, and could be an ideal model for the study on smoke inhalation injury.</p>
Subject(s)
Animals , Dogs , Male , Burns, Inhalation , Disease Models, Animal , Lung Injury , Random Allocation , Smoke Inhalation InjuryABSTRACT
<p><b>OBJECTIVE</b>To investigate the biological activities of the bronchoalveolar lavage fluid (BALF) harvested from dogs with smoke inhalation injury at early post injury stage.</p><p><b>METHODS</b>BALF was harvested from normal dogs and those inflicted by smoke inhalation injury for the employment in the study. Ninety four Wistar rats were employed in the study and were randomly divided into A (n=28), B (n=29) and C (n=37) groups. The rats were perfused intra-tracheally with normal saline, BALF from normal dog and BALF from injured dog, respectively in A, B and C groups. Every 7 rats in each group were used before the perfusion as normal control. The rats in control group and those in A, B and C groups at 4, 12 and 24 hours after BALF perfusion were sacrificed. The survival rate and the pathomorphological gross and microscopic changes in pulmonary tissue in all groups were observed. In addition, the contents of prostaglandin F1alpha/thromboxane B2 (PGF1alpha/TXB2), tumor necrosis factor (TNF-alpha) and myeloperoxidase (MPO) in pulmonary tissue homogenization and the pulmonary capillary permeability were determined simultaneously.</p><p><b>RESULTS</b>All the rats in A and B groups survived, but nine in C group died before sacrificing. The BALF from dogs inflicted by smoke inhalation injury could cause rat lung exhibiting pathomorphological changes similar to those in rats inhaling smoke directly. The rat pulmonary tissue contents of PGF1alpha/TXB2 in A and B groups after the perfusion tended to increase, while that in C group decreased gradually (P <0.01). The rat pulmonary tissue contents of TNF-alpha and MPO content in A and B groups after the perfusion revealed no obvious change (P >0.05), while those in C group increased evidently at 4 hour after the perfusion and decreased thereafter (P <0.05-0.01). The pulmonary capillary permeability in C group was higher than that in A and B groups at 4 hour after the perfusion (P < 0.01).</p><p><b>CONCLUSION</b>The BALF from canine lungs during the early stage of inhalation injury exhibited biological activities. The primary and secondary pulmonary injury could be prevented or ameliorated by massive pulmonary lavage during early post injury stage after smoke inhalation injury.</p>
Subject(s)
Animals , Dogs , Male , Rats , Bronchoalveolar Lavage Fluid , Capillary Permeability , Lung , Pathology , Rats, Wistar , Smoke Inhalation Injury , PathologyABSTRACT
Objective To investigate the existence, intensit y and persisting time of biologic activity of bronchoalveolar lavage fluid (BALF ) collected from dogs with acute severe smoke inhalation injury in early post-i njury stage. Methods BALF was collected 1 h after the est ablishment of acute severe sawdust smoke inhalation injury in 5 dogs, and the fl uid was perfused into the lungs of Wistar rats in the amount of 5 ml/kg (gro up C). Normal saline (group A) and BALF from normal dog (group B) were perfused into the lungs of rats and served as control. The respiratory rate, PaO2, lung water content and the expanding stability of lungs in all rats were determ ined at the time points of 4,12 and 24 h after the purfusion. Results Compared with the rats in group A and B, the rats in group C had higher mortality, wider range in RR, higher lung water content, PaO2 decreased obviou sly and lower lung expanding stability. The rats in control groups showed sl i ght mechanic obstruction in their airways in the course of experiment. Meanwhile ，the rats in group C showed higher oxidative activities and lower total anti-o xidative activities in lung tissues. Conclusion It is certai n that the BALF collected from dogs with acute severe smoke inhalation injury in early post-injury stage could induce obvious injury in lung structure of norma l rats, showing certain mechanic obstruction in small airways. The injuring act ivity of the BALF can be alleviated ultimately 24 h after the perfusion of the B ALF.
ABSTRACT
Objective To study the effect of acute serious smoke inhalation injury to unilateral lung on contralateral lung and the therapeutic efficacy of massive bronchoscopic lavage with saline to the primary injured bronchoalveolus at early stage after smoke inhalation on mitigating the secondary damage of the other lung and so as to confirm the therapeutic validity of lung lavage to smoke inhalation injury. Methods Fifteen mongrel dogs were insufflated with sawdust smoke into left lung and then randomized into 2 groups. The dogs in group A were maintained intravenous glucose saline transfusion and breathed air freely for 24 h after injury. Those in group B received a massive bronchoscopic lavage with 250 ml of saline to injured lung at 1 hour after injury and then were administrated similarly to those in group A. Gas exchange function of bilateral lungs in the process were observed and pathologic and phyiopathologic changes of the lung specimen were examined after the process. Results While the total lavaging volume was kept to 250 ml, the liquid volume remained in left lung after each operating was from 90 ml to 140 ml. All animals had a significant decline in pulmonary function after smoke inhalation injury. PaO2 in group B decreased significantly soon after the lavage and then increased gradually to exceeding that in group A. The left lung showed serious edema similarly in two groups but in right lung the water content was less, dynamic and static compliance was more in group B than in group A. Conclusion Bronchoalveolar massive lavage at early post-injury stage to injured lung after unilateral lung smoke inhalation injury can mitigate secondary damage of the non-injured lung. Lung lavage can decrease the intensity of secondary systemic inflammatory reaction and show a therapeutic validity to smoke inhalation injury.
ABSTRACT
Objective To explore the feasibility and safety of massive lung lavage to dogs in the early stage after acute serious smoke inhalation. Methods A total of 16 dogs were inflicted with smoke inhaled injury and then divided into group A (n=5) without lung lavage, group B (n=6) in which left lung lavage was followed by lavage on the right 30 min later, and group C (n=5) in which the interval of the lavages on the left and right lung was 4 h. Massive lung lavage was carried out in 1 h after the injury under the guiding fiberoptic bronchoscopy and a special ventilation jet was served to supply enough oxygen to the dogs. The stability of pulmonary function and blood circulation were observed at different time points in every group. Results The average operating time of unilateral lung lavage was about 15 minuted and the liquid volume left in every lung after operation was from 100 ml to 140 ml when the total lavaging volume was kept in 250 ml. The changes of hemodynamic parameters were identical in Group B and Group C. Inhalation injury had certain negative effect while lung lavage almost had no effect on the blood circulation of the animals in 2 lavage groups. No serious cardiac arrythemia was found in them during the lavaging. Pulmonary function in Group C was better than that in Group B but worse than that in Group A. In the 2 lavaging groups, PaO2 remained higher than 9.33 kPa（FiO2=0.4）during and after the lavaging. Conclusion The ventilation mode and the lavage method introduced here ensure the safety of massive lung lavage in dogs with acute smoke serious inhalation injury.
ABSTRACT
Objective To investigate the existence, intensit y and persisting time of biologic activity of bronchoalveolar lavage fluid (BALF ) collected from dogs with acute severe smoke inhalation injury in early post-i njury stage. Methods BALF was collected 1 h after the est ablishment of acute severe sawdust smoke inhalation injury in 5 dogs, and the fl uid was perfused into the lungs of Wistar rats in the amount of 5 ml/kg (gro up C). Normal saline (group A) and BALF from normal dog (group B) were perfused into the lungs of rats and served as control. The respiratory rate, PaO2, lung water content and the expanding stability of lungs in all rats were determ ined at the time points of 4,12 and 24 h after the purfusion. Results Compared with the rats in group A and B, the rats in group C had higher mortality, wider range in RR, higher lung water content, PaO2 decreased obviou sly and lower lung expanding stability. The rats in control groups showed sl i ght mechanic obstruction in their airways in the course of experiment. Meanwhile ，the rats in group C showed higher oxidative activities and lower total anti-o xidative activities in lung tissues. Conclusion It is certai n that the BALF collected from dogs with acute severe smoke inhalation injury in early post-injury stage could induce obvious injury in lung structure of norma l rats, showing certain mechanic obstruction in small airways. The injuring act ivity of the BALF can be alleviated ultimately 24 h after the perfusion of the B ALF.
ABSTRACT
Objective To study the effect of acute serious smoke inhalation injury to unilateral lung on contralateral lung and the therapeutic efficacy of massive bronchoscopic lavage with saline to the primary injured bronchoalveolus at early stage after smoke inhalation on mitigating the secondary damage of the other lung and so as to confirm the therapeutic validity of lung lavage to smoke inhalation injury. Methods Fifteen mongrel dogs were insufflated with sawdust smoke into left lung and then randomized into 2 groups. The dogs in group A were maintained intravenous glucose saline transfusion and breathed air freely for 24 h after injury. Those in group B received a massive bronchoscopic lavage with 250 ml of saline to injured lung at 1 hour after injury and then were administrated similarly to those in group A. Gas exchange function of bilateral lungs in the process were observed and pathologic and phyiopathologic changes of the lung specimen were examined after the process. Results While the total lavaging volume was kept to 250 ml, the liquid volume remained in left lung after each operating was from 90 ml to 140 ml. All animals had a significant decline in pulmonary function after smoke inhalation injury. PaO2 in group B decreased significantly soon after the lavage and then increased gradually to exceeding that in group A. The left lung showed serious edema similarly in two groups but in right lung the water content was less, dynamic and static compliance was more in group B than in group A. Conclusion Bronchoalveolar massive lavage at early post-injury stage to injured lung after unilateral lung smoke inhalation injury can mitigate secondary damage of the non-injured lung. Lung lavage can decrease the intensity of secondary systemic inflammatory reaction and show a therapeutic validity to smoke inhalation injury.
ABSTRACT
Objective To explore the feasibility and safety of massive lung lavage to dogs in the early stage after acute serious smoke inhalation. Methods A total of 16 dogs were inflicted with smoke inhaled injury and then divided into group A (n=5) without lung lavage, group B (n=6) in which left lung lavage was followed by lavage on the right 30 min later, and group C (n=5) in which the interval of the lavages on the left and right lung was 4 h. Massive lung lavage was carried out in 1 h after the injury under the guiding fiberoptic bronchoscopy and a special ventilation jet was served to supply enough oxygen to the dogs. The stability of pulmonary function and blood circulation were observed at different time points in every group. Results The average operating time of unilateral lung lavage was about 15 minuted and the liquid volume left in every lung after operation was from 100 ml to 140 ml when the total lavaging volume was kept in 250 ml. The changes of hemodynamic parameters were identical in Group B and Group C. Inhalation injury had certain negative effect while lung lavage almost had no effect on the blood circulation of the animals in 2 lavage groups. No serious cardiac arrythemia was found in them during the lavaging. Pulmonary function in Group C was better than that in Group B but worse than that in Group A. In the 2 lavaging groups, PaO2 remained higher than 9.33 kPa（FiO2=0.4）during and after the lavaging. Conclusion The ventilation mode and the lavage method introduced here ensure the safety of massive lung lavage in dogs with acute smoke serious inhalation injury.