[Shock modeling of large area third-degree burn in miniature swine]

To report a novel method of establishing a stable shock model of swine.

A total of 12 Guangxi BA-MA female miniature swines (aged 4-6 months) into A and B groups according to a random number table. Total body surface area (TBSA) was calculated according to the Meeb-Rubner formula. After intravenous anesthesia and other steps, solidified gasoline was used as burns material to establish TBSA 40% skin burn (Group A: 45 s, Group B: 50 s). Burn depth by was judged by visual and histopathological examination. Fluid resuscitation was instituted at 2 h post injury. At the same time, the hourly and pre-injury data of heart rate (HR), blood pressure (BP), urinary volume, central venous pressure (CVP) and pulmonary arterial wedge pressure (PAWP) were recorded. The actual input quantities of fluid resuscitation were assessed at the 1st and 2nd 24 h post injury. And shock condition was estimated by shock index at 2 h post injury.

All miniature swines were successfully modeled without any mortality. The burn wound observed by visual examination and light microscope showed that Group A was of deep II burn and Group B III burn. Compared with the pre-injury data, HR (111 ± 6 vs 74 ± 9, 119 ± 13 vs 75 ± 13 beats/min) increased, urinary volume (0.99 ± 0.06 vs 1.45 ± 0.05, 0.82 ± 0.04 vs 1.47 ± 0.06 ml×kg(-1)×h(-1)), CVP and PAWP decreased at 2nd 24 h post-injury in two groups (P < 0.01, P < 0.05). But the changes of BP (120 ± 6/93 ± 9 vs 120 ± 6/94 ± 6, 121 ± 15/90 ± 11 vs 124 ± 10/91 ± 8 mm Hg) had no statistical significance (P > 0.05). The average value of HP in 48 h post-injury had no statistical significance in two groups (P > 0.05). The recovery liquid quantity in the first 24 h of Group B (1.66 ± 0.10 ml×kg(-1)×1%(-1) TBSA) was significantly more than Group A (1.53 ± 0.05 ml×kg(-1)×1%(-1) TBSA) (P < 0.05). The ratio between liquid input and output of Groups A and B showed that the comparison had no statistical significance (P > 0.05). In the second 24 h post-injury, the recovery liquid quantity (0.69 ± 0.17, 0.65 ± 0.16 ml×kg(-1)×1%(-1) TBSA) and the ratio between liquid in and out (1.48 ± 0.28, 1.52 ± 0.27)% between Groups A and B had no statistical significance (P > 0.05). The shock index at 2 h post-injury showed that Groups A and B were in shock compensatory period (0.92 ± 0.07) and mild shock state (1.00 ± 0.16) respectively (P > 0.05).

Such a shock model is stable and dependable.