Effects of different fluid resuscitation methods on hemorheology in pigs during burn shock stage

Objective To investigate the impact of different methods of fluid resuscitation on hemorheology during burn shock stage. Methods Twenty four miniature swines were randomly divided into four groups with 6 in each group (succinylated gelatin group, hydroxyethyl starch group, Parkland group and allogeneic plasma group). Severe burn shock model was established by burning miniature swine with napalm. Two hours after injury, succinylated gelatin, hydroxyethyl starch (130/0.4) and swine allogenic plasma were used as colloid (alternative colloid) in fluid resuscitation according to the burn shock fluid resuscitation formula which is commonly accepted in the field of Burns Surgery. In Parkland group, miniature swines received liquid recovery according to Parkland Formula. The vital signs before and within 48 h after burn were observed by Solar 8000i electrocardiomonitor during the process of transfusion. The infusion speed was adjusted based on the heart rate, blood pressure, urine volume and central venous pressure. The level of hematocrit (HCT), viscosity of plasma (ηp), index of rigidity (IR), red cell assembling index (RCA) and erythrocyte electrophoresis time (EFT) were measured at the time of pre-injury as well as 4, 8, 24 and 48 h post-injury and statistical analysis was performed. Results HCT in hydroxyethyl starch group and Parkland group at 8 h post-injury were significantly higher than pre-injury [(0.395±0.047) vs (0.333±0.042), (0.379±0.026) vs (0.352±0.019)] (both P<0.05). And compared with pre-injury, HCT in hydroxyethyl starch (130/0.4) group at 48 h decreased significantly (0.232±0.021) vs (0.333±0.042) (P<0.05). HCT in Parkland group at 24, 48 h post-injury were lower than pre-injury [(0.277±0.021), (0.241±0.029) vs (0.352±0.019)] (both P<0.05). Compared with pre-injury, the levels of ηp in Parkland group decreased substantially at 4, 8 and 24 h post-injury [(1.61±0.07), (1.55±0.07) and (1.63±0.07) vs (1.73±0.04) mPa·s] (all P<0.05). Compared with allogeneic plasma group, IR decreased in succinylated gelatin group at 24, 48 h post-injury [(1.10±0.05 vs 1.26±0.07), (1.11±0.05 vs 1.32±0.05)](both P<0.05). RCA in succinylated gelatin group was significantly higher (both P<0.05) at 4 h (6.80±0.87) than pre-injury (5.92±0.43). RCA in hydroxyethyl starch group at 8 h post-injury (6.73±0.56) was significantly higher (both P<0.05) than pre-injury (6.03±0.53). Compared with pre-injury (17.3±1.3 s, 16.4±1.5 s), the levels of EFT in hydroxyethyl starch group (15.5±1.4 s) and Parkland group (13.4±1.2 s) decreased substantially at 48 h post-injury (both P<0.05). Compared with allogeneic plasma group, the level of EFT in succinylated gelatin group at 4 h post-injury (19.5±2.3 s) increased and decreased at 24 h post-injury (12.0±5.7 s) (both P<0.05). Conclusion During swine burn shock stage, the hemorheological parameters of shock resuscitation with artificial colloid are more stable than those with Parkland formula resuscitation. Key words: Burns; Shock; Artificial colloid; Hydroxyethyl starch; Hemorheology