重度创伤性脑损伤(TBI)后弥漫性脑肿胀在儿童中比成人更常见;然而，目前尚缺乏成熟动物弥漫性脑损伤的模型。作者通过修改最近描述的成年大鼠闭合性头部损伤模型，建立了一种新的成熟大鼠弥漫性严重TBI模型。sd - dawley幼鼠105只(17日龄;平均体重38.5±5.46 g)的患者使用可变重量(0克(假)、75克、100克或125克)从2米高的地方投掷到固定在完整头盖骨上的金属盘上，进行头部撞击。评估死亡率、生理和神经参数(从早期反射恢复到逃逸)以及早期组织病理学变化。在严重损伤(SI)后的急性期(100克从2米的高度投下;50只)，常出现呼吸暂停，死亡率为38%。假性损伤动物(11只)神经系统完全恢复需要4.1±0.23分钟(平均±平均标准误差)，而中度损伤(MI)动物(75 g/2 m;11只大鼠(14.97±3.99 min)和SI(20.57±1.31 min (p < 0.05))。 In the first 24 hours, the sham-injured animals were more active than the injured ones as reflected by a greater net weight gain: 2.9 ± 1.0 g, 1.2 ± 1.6 g, and −0.6 ± 2.1 g in sham-injured, MI, and SI animals, respectively. Immediately after injury, transient hypertension (lasting < 15 seconds) was followed by hypotension (lasting < 3 minutes) and loss of temperature regulation. Both injuries also induced apnea (0.75 ± 0.7 minutes and 1.27 ± 0.53 minutes in MI and SI groups, respectively), which either resolved or deteriorated to death. Intubation and assisted ventilation in animals with SI for 9.57 ± 3.27 minutes in the peritrauma period eliminated mortality (p < 0.05, intubated vs. nonintubated). Histologically, after SI, there was diffuse edema throughout the corpus callosum below the region of injury and in the thalami. Other injuries included neuronal death in the deep nuclei, bilateral disruption of CA3, diffuse subarachnoid hemorrhage, and, in some, ventriculomegaly. Following a diffuse TBI in immature rats, SI produced a mortality rate, neurological deficit, and histological changes similar to those previously reported for an injury resulting from a 450-g weight dropped from 2 m in adult rats. A graded insult was achieved by maintaining the height of the weight drop but varying the weights. Weight loss, acute physiological instability, and acute neurological deficits were also indicative of an SI. Mortality was eliminated when ventilatory support was used during the peritrauma period. This model should be useful in studying the response of the immature rat to diffuse severe TBI.
