Rice H E, Estes J M, Hedrick M H, Bealer J F, Harrison M R, Adzick N S
Department of Surgery, University of California, San Francisco 94143.
J Pediatr Surg. 1994 May;29(5):692-6. doi: 10.1016/0022-3468(94)90743-9.
Congenital cystic adenomatoid malformation (CCAM) can be diagnosed in utero. Nonimmune hydrops associated with CCAM is a predictor of fetal demise. Fetuses with prenatally diagnosed large CCAM tumors and hydrops have undergone successful in utero resection. An animal model is needed to understand the pathophysiology of CCAM and hydrops. To create a model of CCAM and hydrops, the authors implanted an intrathoracic tissue expander in six fetal sheep at 120 days' gestation. The inflatable tissue expander was implanted in the right side of the chest, and arterial, venous, intrathoracic, and intraamniotic pressure catheters were placed. Each day, the expander was inflated with 25 to 50 mL of saline (maximum, 150 mL), ultrasound examination was performed, and all pressure measurements were taken. In all six fetuses, hydrops developed after expander inflation. Expander inflation correlated with an increase in central venous pressure (CVP) (4 +/- 2 mm Hg v 16 +/- 2 mm Hg [mean +/- SD]; P < .05). To simulate in utero CCAM resection, the expander was deflated in four hydropic sheep, resulting in return of the CVP to near baseline and resolution of hydrops. Silicone vascular casts of two postmortem sheep demonstrated lateral displacement and compression of the vena cavae by the expander. The authors successfully created a model of CCAM and hydrops by inflating an intrathoracic tissue expander in fetal sheep. Based on this model, hydrops associated with CCAM results from obstruction of cardiac venous return and central venous hypertension. This pathophysiology is reversed by expander deflation, which simulates in utero CCAM resection.(ABSTRACT TRUNCATED AT 250 WORDS)
先天性囊性腺瘤样畸形（CCAM）可在子宫内被诊断出来。与CCAM相关的非免疫性水肿是胎儿死亡的一个预测指标。产前诊断出患有大型CCAM肿瘤和水肿的胎儿已成功接受子宫内切除术。需要一个动物模型来了解CCAM和水肿的病理生理学。为了创建CCAM和水肿模型，作者在妊娠120天的六只胎羊体内植入了一个胸腔内组织扩张器。将可充气的组织扩张器植入胸部右侧，并放置动脉、静脉、胸腔内和羊膜腔内压力导管。每天用25至50毫升生理盐水（最大量150毫升）给扩张器充气，进行超声检查，并测量所有压力。在所有六只胎羊中，扩张器充气后均出现了水肿。扩张器充气与中心静脉压（CVP）升高相关（4±2毫米汞柱对16±2毫米汞柱[平均值±标准差]；P<.05）。为了模拟子宫内CCAM切除术，在四只出现水肿的胎羊体内将扩张器放气，导致CVP恢复到接近基线水平，水肿消退。对两只死后胎羊的硅胶血管铸型显示，扩张器导致腔静脉出现侧向移位和受压。作者通过在胎羊体内给胸腔内组织扩张器充气成功创建了CCAM和水肿模型。基于该模型，与CCAM相关的水肿是由心脏静脉回流受阻和中心静脉高压引起的。扩张器放气可逆转这种病理生理学，这模拟了子宫内CCAM切除术。（摘要截取自250字）
