Conservative Therapy
Most kidney stones less than 6mm in size that is 70-80% of stones
can be treated conservatively. If pain, nausea and vomiting,
infection can be controlled, most of these stones will pass
spontaneously. Patients need to be able to stay well hydrated
while trying to pass a kidney stone. An attempt to control pain is
with narcotic and anti-inflammatory medication. Use of the
anti-inflammatory may decrease the amount of narcotic needed
to control the pain. Sometimes stones can be followed for
weeks to months if there is no significant obstruction and
patients can tolerate the pain without severe nausea and vomiting
and as long as there is no active infection. If the pain is
too severe, patients can’t stay well hydrated or they
develop persistent fever greater than 101 degrees F, then
some type of intervention is required.
ESWL
ESWL or extracorporeal shock wave lithotripsy
has revolutionized the treatment
of renal stones. Kidney stones less than or equal
to 2cm in size in the kidney or upper ureter are best treated
with ESWL. Usually, this is an outpatient type of procedure
using IV sedation or full anesthesia. Treatment time runs
from 1 to 2 hours. The stone is usually visualized with fluoroscopy
and once centered for treatment, a shock wave is generated
that penetrates the body and impacts upon the stone. After
several hundred to several thousand shocks are given, the
stone gradually pulverizes, and the fragments are passed spontaneously
over the next several days to weeks. Complications of this
procedure include infection so patients are usually maintained
on antibiotics. Blood is usually seen in the urine after ESWL,
but significant bleeding is rare. There is always the possibility
that repeat ESWL may have to be performed if the stone is
hard and difficult to fragment.
Also, patients are advised that other procedures may be needed
including cystoscopic, ureteroscopic, percutaneous or open
procedure.
Percutaneous Nephrolithotomy
Stones larger than 2-3cm are often better treated with percutaneous
nephrolithotomy. Kidney stones that fill the entire renal collecting
system, or staghorn stones, sometimes require both percutaneous
debulking and subsequent ESWL of remaining fragments. With
percutaneous nephrolithotomy, the kidney is accessed through
the flank usually under fluoroscopy. Often this portion of
the procedure is performed by a radiologist. Once the kidney
has been accessed with a needle, a guide wire is placed through
the flank into the kidney and passed down to the ureter. The
second part of this procedure takes place in the operating
room with the patient under anesthesia under the supervision
of a urologist. Sometimes the radiologist is also present
to assist with dilating the tract from the flank to the kidney.
Once this tract is dilated, a scope is inserted through the
patient’s side into the kidney and the kidney stone is treated.
It may be grasped with a basket and removed or it may be fragmented
through the scope with ultrasound, laser, or electrohydraulic
lithotripsy. Fragments are then grasped and removed through
the scope. A catheter is left through the side into the kidney
until it is certain the kidney is draining well and this perc-tube
can be safely removed.
Risks of this procedure include infection, bleeding, or perforation
of the kidney with extravasation of irrigating fluid. Also
damage to adjacent organs is possible in approximately 1%
of cases. Also patients need to know that there is the possibility
of needing repeat procedure, subsequent ESWL, cystoscopic,
ureteroscopic, or open procedure post percutaneous nephrolithotomy.
Cystoscopy-Ureteroscopy
Cytoscopic-ureteroscopic procedures are best used for kidney stones
located in the mid to distal ureter. Access is gained to the
bladder through the urethra with a scope and a guide wire
is placed into the affected ureter. Then either a rigid or
flexible ureteroscope is placed into the ureter and under
direct vision is guided to the level of the stone. Smaller
stones may be grasped or entrapped in a small basket and pulled
from the ureter. Larger stones may require fragmentation with
lithotripsy through the scope. This may be accomplished with
the jackhammer effect of a lithoclast or by using electrohydraulic,
ultrasonic, or laser lithotripsy.
The risks of cystoscopic-ureteroscopic procedures include
infection, bleeding, failure to remove the stone, ureteral
injury.
5) Use of a Ureteral Stent
Any of these procedures may be performed with placement of
a straight or double J stent either prior to, during, or after
the procedure. A stent may be placed down the ureter from
above during a percutaneous procedure, but is most often placed
cystoscopically. It’s usually a “Double J”
stent that is placed cystoscopically over a previously placed
guide wire. The stent curls up in the kidney at the proximal
end and curls in the bladder distally. Double J stents have
multiple perforations to allow the urine to drain from the
kidney down the ureter to the bladder. They may be placed
to bypass a stone, relieve obstruction, or to keep the ureter
from swelling shut after a cystoscopic-ureteroscopic procedure.
If a stent is left, it can easily be removed with a brief
flexible cystoscopic office procedure in males and a small
rigid cystoscopic procedure in females.
6) Open Surgery
With the advent of ESWL, percutaneous nephrolithotomy, and
cystoscopic-ureteroscopic procedures, open surgery is rarely
indicated. It is sometimes indicated in cases with very large
stone burden or cases that don’t respond to one of the
other treatments.
