压迫面积、时间和重量与大鼠挤压伤/挤压综合征的相关性研究

目的 研究压迫面积、压迫时间和压迫重量与局部损伤及全身病理生理反应的相关性,初步摸索可重复的挤压综合征大鼠模型. 方法 清洁级雄性SD大鼠72只,按随机数字表法分为18个小组(每组4只大鼠).将压迫面积(单、双侧后肢)、压迫重量(2,3,4 kg)和压迫时间(4,6,8 h)进行排列组合后形成18种压迫条件.所有大鼠在压迫开始前和解压后3 h测量受压后肢周径,同时取血检测K+、CK、Cr和BUN,并在实验过程中观察肌红蛋白尿的发生率;解压后24 h取其受压局部肌肉及肾脏进行病理切片检查. 结果 所有大鼠解压3 h后受压肢体均明显肿胀(P＜0.05).各组中K+、CK、Cr和BUN均随压迫面积、时间及重量的增加和延长而明显上升(P＜0.05).局部受压肌肉呈明显水肿和坏死表现;肾脏出现肾小球、肾小管充血,压迫重量≥3 kg、压迫时间≥6 h组可见肾小管坏死及管型. 结论压迫时间、重量及面积的增加和延长可增加挤压伤局部损伤和全身反应的严重程度.受压面积为双侧后肢、压迫重量≥3 kg、压迫时间≥6 h可较为稳定地造成大鼠典型的挤压综合征表现,可初步作为建立挤压综合征大鼠模型的实验条件.

Relationship of compression area, time and weight with crush injury/crush syndrome in rats

Objective To investigate the relationship of compression area, time and weight as risky factors with local injury and systemic pathophysiological responses in rats so as to establish repeatable experimental model of crush syndrome. Methods A total of 144 male SD rats were divided into two groups, ie, mortality investigation group and biochemical indicator investigation group. Every group included the same 18 subgroups based on 18 kinds of combination with different levels of compression area (the right or both hind limbs), time (4, 6, 8 hours) and weight (2, 3, 4 kg). The circumference of the compressed hind limbs of all rats were measured and serum potassium (K+), serum creatine phosphokinase (CK), creatinine and carbamide were measured too before compression and three hours after decompression. Incidence of myoglobinuria of all rats was recorded. Muscles and kidneys were evaluated morphologically. Results The compressed hind limbs of all rats swelled significantly after three hours of reperfusion (P ＜ 0. 05). All serum K + , CK, CR and BUN were increased significantly with the increase and prolongation of the compression area, time and weight (P ＜ 0.05). Signs of direct cellular damage and ischemia-reperfusion injury were found in histology specimens of local compressed muscle.Hyperemia of glomeruli and renal tubule was found in the kidneys. Renal tubular necrosis and renal tubular cast were observed in group with compression weight ≥3 kg and compression duration ≥6 hours.Conclusions Increase and prolongation of the compression area, time and weight can aggravate the severity of crush injury. Compression area is more risky factor of severe crush injury. Both hind limbs ascompression area, compression weight ≥ 3 kg and compression duration ≥ 6 hours can be the effective experimental conditions for establishment of crush syndrome model in rats.