and to explore the urethra for stenosis, discover residual urine in the bladder, and
introduce contrast medium into the bladder.
d. Filiform tips and followers are used to dilate narrow strictures. Graduated
woven ureteral catheters are used to introduce radiopaque material or obtain a sterile
urine specimen from the renal pelvis and to help determine renal function.
e. The olive-tipped bougies are used to calibrate the urethra. The silk woven
catheter may be used to manipulate past enlarged prostatic lobes. In some cases, a
catheter stylet is used to insert a catheter. The catheter should be lubricated before the
stylet is inserted. The catheter is drawn taut over the stylet so that its tip cannot
become dislodged. Catheters with inflatable balloons are used for drainage and for
Section III. OPERATIONS ON THE KIDNEY, URETER, AND ADRENAL GLANDS
3-13. GENERAL CONSIDERATIONS
a. Stones, infections, and tumors are the most common causes of urinary tract
obstruction necessitating operations to prevent renal destruction or failure. Obstruction
may also be due to malformations of the urinary tract.
b. Although the causes of kidney stones are obscure, certain conditions such as
obstruction, stasis, or body chemistry predispose to their formation. Stones may form
from various elements: calcium oxalate, calcium phosphate, magnesium ammonium
phosphate, uric acid, and calcium carbonate, or combinations of these substances may
be found. All stones removed at operation are usually subjected to chemical analysis.
Stones obtained as surgical specimens are best submitted in a dry jar. Fixative agents
such as FormalinR can obscure the results of the analysis.
c. Stones in the renal pelvis may drop down into the opening of the ureter (the
uretero-pelvic junction) and occlude it, or they may pass into the ureter and lodge at the
ureterovesical junction or where the ureter passes into the bony pelvis at the level of the
iliac crest. A stone may lodge in a renal calyx and continue to enlarge, eventually filling
the entire calyx or renal pelvis (staghorn stone).
d. Hydroureter, hydronephrosis, and fibrosis with destruction of the renal
parenchyma can result from unrelieved obstruction.
a. General. This operation involves the removal of the kidney. It is done to
treat some congenital unilateral abnormalities causing renal obstruction or severe
hydronephrosis, tumor of the kidney, a severely injured kidney, renal tuberculosis,
calculous pyelonephrosis, and sometimes cortical abscess.