腹腔扩容术治疗猪失血性休克复苏后腹内高压对肝脏的影响

目的研究负压封闭引流(VSD)辅助的腹腔扩容术(IAVI)治疗腹腔高压症(IAH)对肝脏的影响。方法 12只健康成年小型猪(广西巴马)经股动脉插管放血建立失血性休克模型(平均动脉压50mmHg,持续1h),门静脉不全阻断后复苏,成功建立IAH模型8只,随机分为IAVI治疗组(IT组,n=4)及假手术对照组(SC组,n=4)。分别于休克前、IAH后2h、IAVI治疗后22h记录膀胱压(VP)、下腔静脉压(IVCP),检测天冬氨酸转氨酶(AST)、丙氨酸转氨酶(ALT)水平,并行增强CT扫描检查腹部前后径/横径比值及肝脏CT值。手术后26h处死动物,留取肝标本行病理组织学及湿干比检查。结果成功建立模型的8只实验动物VP为21.16±4.63mmHg,与休克前相比,IAH后2h腹部前后径/横径比值明显升高(1.22±1.41 vs 0.96±0.08,P<0.01),其中2只(25%)出现直肠脱垂及压力性尿失禁。IAH后2h血AST、ALT(589.98±14.94、77.03±12.59U/L)明显高于休克前(36.43±2.10、37.86±3.48U/L,P<0.01),肝脏CT值(42.73±4.92HU)明显低于休克前(60.00±6.85HU,P<0.05)。IT组动物观察期内全部存活,SC组2只分别于IAH后18h及20h死亡。手术后22h,IT组VP和IVCP(10.38±0.99、10.40±1.14mmHg)明显低于SC组(32.00±2.82、31.65±3.04mmHg,P<0.01),AST、ALT(215.25±73.40,60.45±3.88U/L)亦明显低于SC组(661.30±14.00,118.25±3.30U/L,P<0.01)。IT组肝湿干比较SC组显著降低(2.32±0.25,5.14±0.71,P<0.01)。病理观察可见IT组肝组织出血、肝细胞空泡变性伴炎症细胞浸润较SC组减轻。结论本模型能较好地模拟失血性休克腹腔填塞及复苏后IAH伴随肝功能损害。IAVI有助于减轻IAH后的肝功能障碍,可能与降低腹腔内压力、减轻肝缺血缺氧有关。

Effect of intra-abdominal volume increment technique for the treatment of intra-abdominal hypertension on the liver after resuscitation of hemorrhagic shock in pig

Objective To observe the effect of VSD-aided intra-abdominal volume increment technique(IAVI) on the liver in the treatment of intra-abdominal hypertension(IAH) following hemorrhagic shock resuscitation in pigs.Methods Twelve healthy mini-pigs(Guangxi Bama) were selected for bloodletting from the femoral artery to reproduce hemorrhagic shock model(mean arterial blood pressure,50mmHg,1h),and IAH model was successfully reproduced in eight pigs by partial occlusion of portal vein.The eight pigs were randomly divided into the intra-abdominal volume increment treatment(IT) group(n=4) and sham operation control(SC) group(n=4).Vesical pressure(VP) and inferior vena cava pressure(IVCP) were observed before shock,2h after IAH,and 22h after IAVI treatment.Aspartate aminotransferase(AST) and alanine aminotransferase(ALT) were measured.In addition,the ratio of the abdominal anteroposterior diameter to the transverse diameter was assessed,and the liver CT values were measured after enhanced CT scanning.The pigs were sacrificed 26h after operation.Liver specimens were collected to measure the ratio of wet weight to dry weight and pathological examination.Results The VP in eight IAH pigs was 21.16±4.63mmHg.The ratio of abdominal anteroposterior diameter to the transverse diameter increased remarkably 2h after IAH compared with that before shock(1.22±1.41 vs 0.96±0.08,P<0.01).However,proctoptosis and stress urinary incontinence were observed in two pigs.In addition,blood AST and ALT levels 2h after IAH(589.98±14.94U/L,77.03±12.59U/L) were remarkably higher compared with those before shock(36.43±2.10,37.86±3.48,P<0.01),and the liver CT value was notably lower than the baseline level(60.00±6.85HU vs 42.73±4.92HU,P<0.05).All pigs in the IT group survived,whereas two pigs in the SC group died 18h and 20h after IAH.Moreover,VP and IAVP in the IT group at 22h after operation(10.38±0.99,10.40±1.14mmHg) were evidently higher than those in the SC group(32.00±2.82,31.65±3.04mmHg,P<0.01).AST and ALT in the IT group(215.25±73.40,60.45±3.88U/L) were also lower than those in the SC group(661.30±14.00,118.25±3.30U/L,P<0.01).The ratio of wet weight to dry weight in the IT group decreased compared with that in the SC group(2.32±0.25 vs 5.14±0.71,P<0.01).Further,the pathological examination showed hemorrhage in the hepatic tissue,vacuolar degeneration of the hepatic cell,and inflammatory cell infiltration in the pigs.The symptoms in the IT group were ameliorated compared with those in the SC group.Conclusions The established model could better reproduce the symptoms of IAH after hemorrhagic shock and fluid resuscitation,accompanied by liver damage.IAVI helps to relieve liver functional disturbance after IAH,which is related to decreased intra-abdominal pressure,and hypoxic-ischemia of the liver.