OBJECTIVETo observe and compare the effects of natural colloid and artificial colloid on pulmonary edema of swine during shock stage of severe burn injury.

METHODSTwelve Guangxi Bama miniature swine were inflicted with 40% TBSA full-thickness burn on the back, and then they were divided into natural colloid group (N) and artificial colloid group (A) according to the random number table, with six swine in each group. At post injury hour (PIH) 2, fluid resuscitation was begun. The main part of electrolyte was lactic acid Ringer's solution. The colloids included swine plasma and hydroxyethyl starch 130/0.4. Before injury and at every hour within PIH 48, heart rate, blood pressure, urine volume, central venous pressure (CVP), and pulmonary arterial wedge pressure (PAWP) were recorded. The mean heart rate, blood pressure, urine volume per hour per kg of body weight, CVP, PAWP, resuscitation liquid volume, and the ratio of fluid intake to output during the first and second PIH 24 were calculated. At PIH 48, lung tissue was harvested for histopathological observation and calculation of lung water ratio. Data were processed with one-way analysis of variance, analysis of variance of repeated measurement, LSD test and independent sample t test.

RESULTS(1) There were no statistically significant differences between two groups in heart rate, blood pressure, and urine volume before injury and during the first and second PIH 24 (P values all above 0.05); during the first PIH 24, the CVP and PAWP of group A were significantly higher than those of group N (P values all below 0.05). Compared with those before injury, the heart rate, CVP and PAWP of two groups during the first and second PIH 24 were significantly higher (P < 0.05 or P < 0.01); the urine volume of group N was decreased during the first PIH 24 (P < 0.05), while there was no significant change in group A (P > 0.05); the urine volumes of two groups during the second PIH 24 were increased, while no statistically significant differences were observed (P values all above 0.05). There were no statistically significant differences in blood pressure of two groups between the first, second PIH 24 and before injury (P values all above 0.05). (2) There were no statistically significant differences in the resuscitation liquid volume and fluid intake to output ratio between two groups during the first and second PIH 24 (P values all above 0.05). (3) The alveolar septum was found widened in varying degrees, and there were edema fluid accumulating and inflammatory cell infiltrating within the pulmonary interstitial of lung tissue sections in both two groups. (4) The lung water ratio of group N [(71 ± 10)%] was not statistically significant different from that of group A [(79 ± 4)%, t = -1.753, P > 0.05].

CONCLUSIONSThe natural colloid or artificial colloid (hydroxyethyl starch 130/0.4) applied during shock stage had similar effects on pulmonary edema in swine with severe burn.