目的：建立中重度脓毒症长期生存大鼠模型，观察脓毒症自然转归的过程，为研究脓毒症提供新思路和方法。方法将40只SD大鼠分为对照组（ sham组，8只）与盲肠结扎穿孔术组（ cecal ligation and puncture， CLP组，32只），所有操作均在小动物麻醉机，七氟烷吸入麻醉下完成。所有大鼠在其右颈部建立动静脉通路。术后恢复24 h后，CLP组大鼠通过盲肠结扎穿孔术致脓毒症。手术完毕后将大鼠转移到恢复室（室内温度22～25℃），单笼饲养。术后静脉补液按1∶1比例分别给予6％HEAS和5％葡萄糖注射液，第1、2天补液量为20 mL／kg／12 h，之后液体减半直至大鼠开始饮食。根据大鼠生存情况CLP组大鼠自然分为生存组（ survival组）和死亡组（ dead组）。观察术后大鼠至30 d，记录大鼠的症状表现、体重变化、IL⁃10血浆浓度的变化，并解剖观察腹腔内脏器改变。结果（1）CLP组术后24 h内生存率为75％，72 h内生存率为62�5％，7 d内生存率为50％。（2）根据脓毒症严重程度评估系统，32只CLP组大鼠在术后24 h均达到中重度脓毒症程度。（3）手术后，survival组与sham组体重均有下降。 survival组大鼠从第4天开始体重下降明显（P＝0�017）。 survival组大鼠在术后第6天体重下降至最低，较原体重下降（8�51±2�23）％；sham组则在术后第4天体重最低，较原体重下降（2�73±1�82）％，两组差异具有统计学意义（ P ＝0�026）。两组大鼠在术后第30天时，体重的最大升高率（ sham 组（16�16±2�39）％与survival组（13�03±3�74）％比无明显差异（P＝0�29）。（4）术后1 d与术前（0 d）相比，三组IL⁃10血浆浓度均有升高，survival组（P＝0�000）和dead组升高明显（P＝0�010）。（5）腹部解剖见：dead组大量恶臭血性腹水，结扎肠管紫黑，无包裹，无粘连。 survival组腹腔广泛粘连，大网膜失去原有形态及光泽，趋向结扎肠管，但无脓肿包裹。 sham组解剖未见异常。 survival 组大鼠脾脏占体重的（2�64±0�37）‰， sham 组大鼠脾脏占体重的比例为（1�63±0�20）‰，两者差异具有统计学意义（P ＝0�032）。结论本实验为建立CLP中重度脓毒症长期生存者模型提供可靠的控制CLP的措施和筛选模型的方法，使其基本符合脓毒症的发生发展规律。%Objective Establish a Long⁃term Survival Rat Model of Sepsis for recovery naturally, and the idea of researching about sepsis survivors may point out new research ideas and methods for sepsis. Methods 40 SD rats were divided into the sham group (8) and the CLP group (32), with all surgical operations under the small animal anesthesia machine and sevoflurane inhalation anesthesia. PVC tubes were inserted into the right carotid artery and jugular vein, respectively. After a postoperative recovery of 24 hours, the rats in the CLP group received the cecal ligation and puncture ( CLP) , which caused sepsis. The rats were then transferred to the single cages in the recovery room ( with the temperature kept between 22~25℃) . After the surgery, we commenced fluid resuscitation, consisting of a solution 6% hetastarch and 5% Glucose in the ratio of 1:1. The amount was 20 mL/kg/12h on the first and second days after the surgery. Then it was halved until the rats started eating. These rats were observed about performance, weight and concentration of IL⁃10 until 30 days after the surgery, when they were anatomized and the change of their organs was watched. Results (1) The survival rate was 75% at 24 h, 62�5% at 72 h, 50% on 7 d after CLP in the CLP group. ( 2 ) Based on the severity of sepsis evaluation system, 32 rats at 24 h after CLP reached moderate to severe sepsis. ( 3 ) The body weight were decreased in both survival group and the sham group after CLP. The body weight of rats in survival group fell from the fourth day of survival was significantly (P=0�017), and to a minimum after the first six days, compared with the original weight loss (8�51 ± 2�23)%. The body weight of rats in sham group fell to a minimum after the first four days, by which the lowest body weight loss (2�73 ± 1�82)% than the original weight. The difference between two groups was statistically significant (P=0�026). After 30 days, the maximum weight increase rates[sham group (16�16 ±2�39)% vs survival group (13�03 ± 3�74)%]were not different significantly (P=0�29). (4) Compared the preoperative (0 d) with postoperative 1d, all the plasma concentration of IL⁃10 in three groups was increased, which in survival group (P=0�000) and in dead group increased significantly ( P=0�010 ) . ( 5 ) Shown by abdominal anatomy, a large set of foetor and bloody ascites, black bowel, with no encapsulated abscess and adhesion in dead group; Abdominal adhesions, omental with losing shape and gloss and tending to ligation intestine, but no encapsulated abscess in survival group;no abnormal anatomy in sham group. The weight of spleen in total body weight ration was ( 2�64 ± 0�37 ) ‰ in survival group and ( 1�63 ± 0�20 ) ‰ in sham group. The difference between two group was statistically significant ( P = 0�032 ) . Conclusions This experiment provided reliable measures of the CLP and methods of screening model, for the establishment of CLP in severe sepsis model of long⁃term survivors, which is basically in accordance with the occurrence and development of sepsis clinically.
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