Is a vesicoamniotic shunt intrinsically bad? Shunting a normal fetal bladder.
BACKGROUND
We previously demonstrated that in utero vesicoamniotic shunting of obstructive uropathy in fetal lambs produces a shrunken noncompliant bladder. We hypothesized that the normal fetal bladder filling and emptying cycle in fetal life is critical to the development of normal bladder function.


METHODS
We placed vesicoamniotic shunts in 4 normal fetal lambs at 74 days' gestation. The fetuses were delivered at term (145 days), and bladder volume and compliance were measured and compared with those measurements in 3 normal term fetuses. The lambs were then killed and the renal tracts and bladders removed submitted to histologic examination.


RESULTS
All shunted lambs survived to term. Three normal control lambs were delivered at term. The mean bladder volume in shunted lambs was 4 +/- 2.8 mL (n = 4) compared with 60 +/- 17 mL (n = 3) in control lambs (P < .05). Bladders in the shunted lambs had very poor compliance compared with normal lambs' bladders. Histologic examination of the shunted bladders showed increased fibrosis and distortion of the muscle layers compared with control bladders.


CONCLUSIONS
Even in the absence of obstruction, preventing normal bladder filling and emptying in fetal life produces fibrotic bladders with poor compliance.
Kitagawa
Hiroaki
H
Division of Pediatric Surgery, St Marianna University School of Medicine, 2-16-1, Sugao, Miyamal-ku, Kawasaki 216-8511, Japan. h2kita@marianna-u.ac.jp
Pringle
Kevin C
KC
Koike
Junki
J
Nagae
Hideki
H
Zuccollo
Jane
J
Aoba
Takeshi
T
Seki
Yasuji
Y
Nagae
Chiai
C
Tadokoro
Mamoru
M
D000650:Amnion / Q000601:surgery*; D000714:Anastomosis, Surgical; D000818:Animals; D005260:Female; D005315:Fetal Diseases / Q000601:surgery*; D023421:Models, Animal; D011247:Pregnancy; D011270:Pregnancy, Animal; D011897:Random Allocation; D012016:Reference Values; D012680:Sensitivity and Specificity; D012756:Sheep; D014524:Urethral Obstruction / Q000601:surgery; D001743:Urinary Bladder / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods*