Effect of Hypothermia on the Prevention of Ventilator-Induced Lung Injury in Rats.
10.4046/trd.2001.50.5.540
- Author:
Chae Man LIM
;
Sang Bum HONG
;
Younsuck KOH
;
Tae Sun SHIM
;
Sang Do LEE
;
Woo Sung KIM
;
Dong Soon KIM
;
Won Dong KIM
- Publication Type:Original Article
- Keywords:
Ventilator-induced lung injury;
Hypothermia;
Cardiac output;
Pressure-volume curve;
Alveolar hemorrhage;
Permeability edema;
Bronchalveolar lavage fluid
- MeSH:
Animals;
Cardiac Output;
Hemorrhage;
Humans;
Hypothermia*;
Lung;
Male;
Oxidoreductases;
Permeability;
Positive-Pressure Respiration;
Pulmonary Edema;
Rats*;
Rats, Sprague-Dawley;
Respiration, Artificial;
Tidal Volume;
Ventilation;
Ventilator-Induced Lung Injury*
- From:Tuberculosis and Respiratory Diseases
2001;50(5):540-548
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Because ventilator-induced lung injury is partly dependent on the intensity of vascular flow, we hypothesized that hypothermia may attenuate the degree of such an injury through a reduced cardiac output. METHODS: Twenty-seven male Sprague-Dawley rats were randomly assigned to normothermia (37±1℃)-injurious ventilation (NT-V) group (n=10), hypothermia (27±1℃)-injurious ventilation (HT-V) group (n=10), or nonventilated control group (n=7). The two termal groups were subjected to injurious mechanical ventilation for 20 min with peak airway pressure 30cm H2O at zero positive end-expiratory pressure, which was translated to tidal volume 54±6ml in the NT-v group and 53±4ml in the HT-V group(p>0.05). RESULTS: Pressure-volume(P-V) curve after the injurious ventilation was almost identical to the baseline P-V curve in the HT-V group, whereas it was shifted rightward in the NT-V group. On gross inspection, the lungs of the HT-V group appeared smaller in size, and showed less hemorrhage especially at the dependent regions, than the lungs of the NT-V group. [Wet lung weight(g)/body weigh (kg)] (1.6±0.1 vs 2.4±1.2 ; p=0.014) and [wet lung weight/dry lung weight] (5.0±0.1 vs 6.1±0.8 ; p=0.046) of the HT-V group were both lower than those of the NT-V group, while not different from those of the control group(1.4±0.4, 4.8±0.4, respectivyly). Protein concentration of the BAL fluid of the HT-V group was lower than that of the NT-V group(1,374±726 ug/ml vs 3,471±1,985 ug/ml;p=0.003). Lactic dehydrogenase level of the BAL fluid of the HT-V group was lower than that of the NT-V group(0.18±0.10 unit/ml vs 0.43±0.22 unit/ml;p=0.046). CONCLUSIONS: Hypothermia attenuated pulmonary hemorrhage, permeability pulmonary edema, and alveolar cellular injuries associated with injurious mechanical ventilation, and preserved normal P-V characteristics of the lung in rats.
