Effect of mechanical ventilation with cold air on canine pulmonary function and body temperature in dogs
WEI Fu-sheng, YANG Lei, MA Long-xian
Published 2011-12-15
Cite as Int J Anesth Resus, 2011,32(06): 695-699. DOI: 10.3760/cma.j.issn.1673-4378.2011.12.015
Abstract
Objective To investigate the effect of mechanical ventilation with cold air on body temperature,pneodynamics,blood gas parameters and histological changes of lung tissue in dogs.Methods Eighteen healthy male dogs were randomly divided into two groups (n=9):hypothermia group and normothermia group.The animals were ventilated with cold air (4℃) or normal air (25℃) respectively.Ventilation parameters in each group were set as:VT=15 ml/kg,RR =15 bpm,I:E=1:2.The body temperatures(Tnp,Tb,Ta) were recorded immediately and repeated every 30 min until it counted to 240 min.Blood gas parameters (PaO2,PaCO2,pH) and pneodynamic parameters (Raw,Ppeak,Cstat) were measured at 0,30 min,1,2,3 h and 4 h after intubation.Plasma cytokine (TNF-α,IL-6) concentrations at 0 min,2 h and 4 h were measured using ELISA,and histopathologic appearance of lung tissue was observed under a light microscopy.Results There were no significant differences in body temperatures between the two groups (P>0.05).There were no statistical significances in PaO2,PaCO2,pH,Raw,Ppeak,or Cstat values at different times between the hypothermia group and the normothermia group.Plasma IL-6 concentrations at 2 h and 4 h increased significantly in both groups compared with baseline values.However,concentrations of serum IL-6 at 2 h and 4 h were lower in hypothermia group compared with normothermia group[ (0.292 ±0.024) μg/L vs (0.312 ±0.133) μg/L at 2 h; (0.281±0.022) μg/L vs (0.301±0.031 ) μg/L at 4 h ].Plasma TNF-α concentration at 2 h increased in both groups compared with basal level.But there were no significant differences in plasma TNF-α concentration between the two groups.Cumulative mean histology scores showed lower in hypothermia group (2.44 ±1.03) than that in normothermia group (4.01±1.31,P<0.05).Conclusion Compared with normal air mechanical ventilation,cold air ventilation at 4 ℃ has no effect on body temperature,pneodynamics or blood-gas exchange,but it has a beneficial effect on attenuating the elevation of serum IL-6 concentration and reducing the injury of lung tissue.
Key words:
Cold air; Mechanical ventilation; Canine; Body temperature; Respiratory
Contributor Information
WEI Fu-sheng
Department of A nesthesiology, the First Affiliated Hospital of Nanchang University, Nanehang 330006, China
YANG Lei
Department of A nesthesiology, the First Affiliated Hospital of Nanchang University, Nanehang 330006, China
MA Long-xian
Department of A nesthesiology, the First Affiliated Hospital of Nanchang University, Nanehang 330006, China