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How Long Does it Take a Child’s Kidney to Drain after Retrograde Pyelography?
THE JOURNAL OF UROLOGY
Vol. 87, No. 5 May 1962 Copyright© 1962 hy The Williams & Wilkins Co. Printed in U.S.A.
HOW L03'\G DOES IT TAKE A CHILD'S KIDNEY TO DRAIN AFTER RETROGRADE PYELOGRAPHY? FREDERICK C. MARSHALL* From the Columbia-Presbyterian Medical Center, the Squier Urological Clinic, New York 32, N. Y.
The "trapping" film, or "trap" film is an x-ray taken to demonstrate any delay in the emptying of contrast medium from the renal pelvis and ureter into the bladc18r. Trapping films are usually obtained at intervals following retrograde pyelography, but can also be obtained following cystography, if V8sicoureteral reflux occurs. Delay in emptying of the contrast material from the upper tracts into the bladder is considered to indicate obstruction of the renal pelvis or ureter, or impaired function of the kidney. Such a delay is call8d "trapping" (of contrast medium) in the pelvis and/or ureter. In children, a comparison of successive examinations of this type may aid in ascertaining whether an obstructive condition with renal deterioration is progressive, stable, or improving. Important as the trapping film can be, there appears to be no standard technique for making such studies. No clinical work could be found in the literature which presented normal and abnormal renal drainage times, the factors ,vhich alter drainage time, and the conditions under which drainage time should be evaluated. Complete emptying of the renal pelvis and ureter in 5 to 10 minutes has been demonstrated in anesthetized children (ages not stated) with normal urinary tracts. 1 In the same study, several children with megaureter and reflux, but without obstruction, demonstrated complete emptying of the renal pelvis and ureter in 6 to 10 minutes following cystograms which were presumably done while the patients were awake. The author did not give the ages of his patients but stated that he felt his findings supported those of Campbell on this subject. Campbell 2 states, in describing "trapping" studies, " ... no attern.pt is made to empty the Accepted for publication October 3, 1961. This work was supported in part by a gift from the Goldman Fund. * Present address: Baker Clinic, Edmonton, Alberta, Canada. 1 Stephens, F. D.: Megaureter. Austral. & New Zealand J. Surg., 23: 197-205, 1954. 2 Campbell, M. F.: Clinical Pediatric Urology. Philadelphia: W. B. Saunders Co., 1951, p. 95. 7:30
injected pelves and ureters by catheter following retrograde pyelography. "Following removal of the catheters, the child is kept on the table for 5 to 10 minutes for a trap film exposure to determine the rate and extent of ureteral and pelvic emptying; in short, for evidence of upper tract urinary stasis. In an infant the x-ray exposure is made 5 minutes after the catheters are withdrawn, and in older children after 6 to 10 minutes, according to age. Trap films may show pelvic retention of medium 2 or 3 hours after pyelography and data obtained by this technique arc often the most valuable of the examination. For this reason trap films should always be made following retrograde pyelograms." Later in his book, discussing excretory urography, Carnpbell3 states: "As determined urographically, the pelvis of a child normally empties itself in 2 to 4 minutes, sometimes in 30 to 40 seconds. The urographic demonstration of fluid retention after 5 minutes may be considered pathologic retention. Delayed pelvic emptying time may be readily demonstrated by excretory urography and has the added advantage of 1) bilateral observation for comparison, and 2) absence of instrumental interference with normal pelviurcteral activity." \Ve would conclude from the foregoing statements that the emptying time of the normal renal pelvis and ureter is less than 10 minutes, and usually less than 5 minutes, and that the younger the child, the shorter the emptying time. Details about the age of the patients tested, and whether anesthesia was given, were not included in all instances by these authors. Since continuing excretion of contrast medium occurs in excretory urography, information on renal pelvic drainage time obtained by this technique ,mule! seem to be only of a very general nature. The present study was undertaken to determine the time required for the contrast medium used in retrograde pyelography to drain com3 Campbell, M. F.: Clinical Pediatric Urology. Philadelphia: W. B. Saunders Co., 1951, p. 147.
RETHOGRADE PYffiLOGRAPHY
with :1 variety of anesthetic a.gents. In rnost the Butkrfirkl size l fiF double rhildnm's cystourethroscope 1vas used to the: bladder and to introduc:e one EiF or two 4T uretcrnl cmtheters. The ddail~ of the films varied with 1:acl1 1mticnt ancl obtainer! depemliug on thr· circmnst:mcc·s of
pl,~tel)' to the hlaclder in u, g:rnup of c:hilclnm with normal and almorrnal trnet~, and under a, of conditiorn; 1.rith and witliout general ,t.ue:.;tlicsia, At the l:rological Clinic al! anesthesia 11cdiatrir: for c:ystoscopy, except in 1mu8u:1l cirnnnstances,
C.H,88.
METHOD
The patients formed fi groups: · Three ,rnd Group nornml upper anc;sthetized, 1vith urinary trads undenn:nt r:yctosC'OJlY and bilateral or unilateral rdrogradc pyelograph~' m lhc supine pmition. Fifteen :md ;30 minute ("trapping") films \H:l"l, taken with tlic still on the table, the legs den1kcl in stirrupc, Gronp B: Two patients, deh)'clratecl aucl rnH','i tlwtizecl, with unilateral upper tract abnorrnnli, ties m1denvent (oystoscop.\' \\"ith bil::itPral unilateral retrograde pyelogn1.phy in th" position, Fift1::m1 and ;30 minute film,,
1) Pat:ients, Patients were sdcd,ed for study if there was a clinical indication for retrograde ) if the cl1ild was in good general health and old enough that the, slight prolongation of ancsthcRia ncc'l:ss,uy for tlw study would not be detrimental. Eleven µatif'.nts 11 ere studied: 4 girls and 7 boys, aged 4 to 12 yearn, ,vith u variety of urological conditiorrn, 2) Pro1:eilu1'e, Patic;nts 1n:rc; dcbydrntccl for fi to 12 hours clepc;ndiug on age and the time of cvstoscopy. Al I patient;, receiYecl routine preJ ncsthetic: medication and hurl general anesthe~ia,
TABLE
Group
IVP
Diagnosis
Enuresis.
/L Functionally normal upper trads. Anes-
Ure.th . stenosis. }En. R & L reflnx. Neurugenic bladder.
t.heti1.ccL Dehydrated. Snpine.
B. Unilateral abnormality. ,,\nesthci. ized. Dehydrated, Supine. C. Ftu1ctiona.ll:\' nornlal.
L
Nonnal, wit.Ji Jargc bladder. No nppfT tract dilatation. Enlarged L renal pelvis.
R. rgp .. incomplete in 1.5 m. cr,1n-nletc in ;;o rn. R & L rgp~; R nearly complete in 15 m. L ineornplctl' in 2 hr,-,
Enuresis.
Minor anomaly, L upper calyx.
R
Post, R. herninephrce-
R post-op kidney. L n'duplication.
R & L rgps; anesth. --H. iucoinplete in 30 m., L near complete in 15 m · mYake--R co111plete in ;H)--{iO m., L cornplet.e iu 15 n1 R rgp; auesth., ineumpldc in :.rn rn awake, incornplete in (iO lll.
Post-vyclopbst,y (left)
F
023U75
F
R rgp; incomplete in 15 m. R & L rgps; R nuarly comr,!dc i.11 20 m. L complete in 20 n1. H. & L rgps; bilaterally incompi0tt' .i.n 15 m. hut complete in 30 rn.
R nrcteral strictnre (mild).
1:J\J2D5.J,
R upper tract, reduplication. Normal
Study Done: Drainage TinH.:
Ancst.l1ct,ized. Dehydrated, then n.wake &, I1ydratf'd.
D.
r:-- nilatcral abnormal-
12
ity. )._nesthetized &
ton1)·.
dehydrated, then a.wake & hydrated.
:u u
Congenital R mega-
ureter.
E. Fnnctionally normal. Anesthetized. Hy-
R hydroureteroncplnosis (mild)
maht:r. Anl~stbetized. Dcl1y-drated. Hc,Hl up.
218-!3:)
& L l'g;ps: incomplete_> in [) m, nearly complete in 10 rn., cotnpl.(~tt i.n 15 rn.
M
Post-renal tutJerculosis.
Nonnal.
R
M l1
Post-acute c:ystitis.
Normal.
R & L rgp1:,; incomplek in 5 rn. lt111 pine), cornplcte i.n 10 rn. (hea.d 11p). R & L rgps; R. incomplete in 16 (head np) L romplet.e in 15 rn (head-npJ.
drated.
F. Bi- or uuilaL abnor-
& L rgps; :-rnestbetized incorn· pletc in :rn Ill.. awake-- ·curuplc~i.<'. i.r, 15 m
H marked, L min.
H. l.i-:,,,·clroureternne ..
phrosis.
,\l.ibreviatlons; R = riglir.; L = left; rgp = retrogra
732
FREDERICK C. MARSHALL
_FIG. 1. Retrograde pyelograms, with 15 and 30 mmute delayed films on patient No. 1493703 under ge_neral anesthesia .. Above, normal upper tracts. M1dd)e, partial dramag_e. Below, complete drainage bilaterally, at 30 mmutes.
were obtained with the patient still on the cystoscopy table, and in one case a 2 hour delayed film was taken after the patient had returned to the ward. Group C: One patient, dehydrated and anesthetized, with functionally normal upper urinary tracts, underwent bilateral retrograde pyelography and 15 and 30 minute delayed or "trapping" films. Ureteral catheters were replaced and taped to an indwelling Foley catheter. Three hours later, with the child then able to sit, and stand, and after taking some fluids, the retrograde pyelograms with delayed films were repeated. Group D: Two patients, dehydrated and anesthetized, with unilateral upper tract abnormalities had unilateral or bilateral retrograde pyelography, with in one case 20 minute, and in the other 15 and 30 minute delayed films. Ureteral catheters were then replaced, as in group D, and the pyelogram with trapping films was repeated after several hours.
_FIG. 2. Retrograde pyelograms, with 15 and 30 mmute delayed films taken on patient No. 236625, u_nder general anesthesia. Above, normal right kidney, and large left kidney and pelvis following pyeloplasty. Middle, 15 minute delayed film shows n'°'.arly complete drainage on the right. Below, 30 mmute delayed film shows complete right drainao-e and severe 'trapping' on the left. Contrast mediu~n was still visible in this abnormal kidney 2 hours following pyelography.
Group E: One patient, anesthetized and hydrated intravenously, with functionally normal Llpper urinary tracts following renal tuberculosis underwent bilateral retrograde pyelography and 5, 10 and 15 minute delayed or "trapping" films were taken. Group F: Two patients, dehydrated and anesthetized, one with normal and the other with abnormal upper urinary tracts, had bilateral retrograde pyelograms done, and while still anesthetized, were placed in a position with the superior part of the body elevated to approxi-
HETROGRADJ~ PYELOGRAJ'HY
.Fm. 3. X-rays taken , a'.1-d 15 minutes following retrograde pyclography in pn1,icnt i\o, 1392954 several hours after (patient awake). a, ."\ ormaI appearing left kidney, on rc'1:rog;n1d1) pyelogrmn. b, Fifteen uu,rncc,,o later, complete drainage. ·· ·
mately :30 degrees above the horizontal (30 degree position) while 5 and 10, or 15 minute films were taken. RESUL'l':S
Table I summarizes the pati<,nts according to with age, sex, diagnosis, excretory llrogrnphic findings, and the time required for the upper tracts to drain following retrograde
groups,
pydography nnder test conditions. A. Films of the ::i c)hilclren in this group demonstrated that following retrograde pye]ography, with the patient dehydrated, anes-
that under rnnditions ~imilar to tbosc' in gro11p A, a relati\ el,v minor and minimally obstrnctiw 0
anomaly could prolong complete upper trad, drainage b()yond ;30 minutes, and that tlw obstrncted part of the) collecting .system take slightly longer than 30 minutes to draiu completely. ·whe,n tlie patient was mrnkt,, hydrated ancl sitting up, howC\cr, and retrngrade pyelography ,i-as clone through a catheter left indwelling at cystoscopy, the contrast inc-· clium drained to the blaclder in le:,:~ than 15 minutes (fig. :3). D. Films of these 2 r:hildren demonstrated that following retrograde ffith the patient dehydrated and am'st!wtizeC:, the normal upper tract drainage time wn::: bet\l'een 15 and 30 minutes. When the was awake, ac:tivc and hydrated, tlw normal upper tract drainage time following pyel ogra Jihy using ca thetcrs inserted at, c_rnto~eopy was less than 15 minutes. ,\lmornrnl upper LJrinary tracts took longer to drain than Llw normal upp<)r trads in both case8, In the first patient a poorly functioning right kidne:' follow-
thetized, and wpine on the cystoscopy table, contrast medium drained cornpletcly from the normal upper urinary trac:t to the bladder m between 15 and :30 minutes, as indicated dcla,vcd x-rays (fig. l). Group B. Films of the 2 patients in this group clemonstratecl that under conditions similar to those in group >\, nppe,r urinary tract abnormali-ties might or might not prolong clrainag<) time beyond the normal 15 to 30 minutes, depending on the nature of the abnormality. The first patient with a mild right ureteral stricture emptied (:ontrast material completely from his right kidney between L5 and ::io minutes. The
ing hcrninepbrectomy had drained by ;30 minutes during anesthesia, and drained c:ompl<'tely ,Yith the patient
second patient with a large left renal pelvis fol-·
between 30 and f-iO minutes. The second
lowing a pycloplasty dirl not empty contrast material r:ompletely from that kidney 2 hours, while his normal kiclne,1- hacl nearly completely drained 15 minutes (fig. 2). C. Films of this patient demonstrated
with a congenital megalourPkr, did not empty his kidney and ureter by 1 hour, e\"t'n awake (fig. 4). E. The films of thiH cbild (fig. ;S) demonstrated that under conditions similar to those in
734
FREDERICK C, MARSHALL
Fm. 5. X-rays taken immediately, and 10 minutes following retrograde pyelography in patient ~ o. 156483 under general anesthesia, and hydrated intravenously. Above, pyelograms show essentially normal upper tracts; right side is slightly overdistended. Below, 10 minutes later, there is complete drainage on left, and nearly complete drainage on right. Fifteen minute delayed film showed complete drainage bilaterally. Fm. 4. Retrograde pyelograms and delayed films on patient No. 023975. With patient dehydrated and anesthetized, retrograde pyelograms, a, demonstrate deformed right renal pelvis following heminephrectomy, with normal left upper half of double kidney. b, Fifteen minutes later, partial drainage on normal left side. c, Thirty minutes later, left kidney has drained completely, but abnormal right kidney still contains contrast medium. Later, with patient awake and hydrated, retrograde pyelograms d, and 15 minutes later, delayed films e, show complete drainage on left side, but trapping on right. group A, but with intravenous hydration, the drainage time of functionally normal upper urinary tracts could be decreased from the usual 15 to 30 minutes to between 10 and 15 minutes. Group F. Films of these 2 patients demonstrated that under conditions similar to those in group A, but with the patient in the 30 degree "head-up" position, the drainage time of essentially normal upper urinary tracts following retrograde pyelography could be decreased to less than 15 minutes, in the anesthetized patient.
The second patient in this group, with marked vesicoureteral reflux on the right side, did not empty that abnormal upper tract by 15 minutes, even though the "head-up" position was used (fig. 6). DISCUSSIOK
The "trapping film" is one of a group of studies with which the function of the upper urinary tracts can be evaluated. If vesicouretera] reflux occurs, delayed or trapping films obtained following voiding cystourethrography or with the urethral catheter open following cystography, will demonstrate how rapidly urine can drain from the renal pelvis and ureter to the bladder. vVhcn the vesicoureteral valve is competent, the cystogram gives no information about the upper urinary tracts. If cystoscopy and retrograde pyelography are necessary in such cases, then "delayed" or "trapping" films are easily obtained. The interpretation of such films depends considerably upon their being done according to a
RETROGRADE PYELOGRAPHY
Fm. 6. Retrograde pyelograms and 15 minute delayed film on patient No. 1285902 under general anesthesia. Above, film shows normal left kidney, and pyelocalyectasis on right secondary to vesicoureteral reflux. Below, with patient in 'head-up' position, 15 minute delayed film shows complete drainage on left, and trapping on abnormal right side. standard technique with a knowledge of what normal and abnormal drainage times are and of the factors that can alter the time required for the upper urinary tract to drain completely to the bladder. The rate of drainage of urine from the upper urinary tracts to the bladder depends upon several factors; an attempt to measure this rate by introducing a radiographic medium through a catheter into the renal pelvis, then taking a series of x-rays with the patient either anesthetized or awake adds still further variables. The most important factors which influence the study are: Urinary output. The output of urine is decreased in advanced renal parenchymal disease, renal arterial obstruction, dehydration, anesthesia, and shock. Dilution of the radiographic material introduced by retrograde pyelography, to the point where it is no longer visible in the renal pelvis on x-ray, depends upon the urine flow rate, and variation in this rate will increase
735
or decrease the drainage time as demonstrated by trapping films. Volume of the collecting system. The volume of the renal pelvis and ureters is increased in nearly all upper tract obstructive conditions, and if urinary output remains unchanged, it will take a correspondingly longer time for introduced contrast medium to be "cleared" to the bladder. Obstruction. Obstructive conditions in themselves probably do not delay drainage of the upper tracts except as they produce alterations in urine formation rate, and increase in the volume of the pelvis and ureter. Gravity. Most contrast media used in urology are denser than urine and this fact, together with the possibility that gravity speeds upper tract drainage when the body is upright, may explain the distinctly more rapid upper tract drainage, which the semi-vertical position produced, as documented in this study. Age. It is probable that the high urine volumes of infants in relation to their body weights, and therefore to the size of their urinary collecting systems, make for a rapid upper tract drainage time, as Campbell 2 has stated. No information in this area has been obtained in this study, as our youngest patient was 4 years old. As a result of experience gained in obtaining the "trapping" films described in this paper, the following standard trapping film study is suggested for children in whom cystoscopy is done with general anesthesia. 1) Child is dehydrated for 6 to 12 hours prior to cystoscopy, depending on age. 2) General anesthesia is given, using intravenous fluids only as necessary. 3) Cystoscopic examination is made of the bladder and urethra. 4) Retrograde pyelography is performed in the usual way and the ureteral catheters are withdrawn from the ureters. 5) If the retrograde pyelograms are satisfactory, x-rays are obtained 15 and 30 minutes following the initial retrograde injection, these being the 15 and 30 minute delayed or "trapping" films. Note: The patient may be awakened from anesthesia following the 15 minute film, but should be kept on the cystoscopy table in the supine position with legs in the stirrups until the 30 minute film is obtained. 6) If contrast medium is still visible in the renal pelvis on the 30 minute film, then further
736
FREDERICK C. MARSHALL
delayed films should be ordered for 1 or 2 hours and even 24 hours if indicated. The standard trapping film study just outlined may be altered to decrease the length of anesthesia by a) intravenous hydration prior to anesthesia, b) tilting the head of the cystoscopic table up to a 30 degree angle with the horizontal following withdrawal of the catheters, or c) leaving the ureteral catheters in place, taped to a urethral Foley catheter and obtaining retrograde pyelograms with delayed films 3 to 4 hours later when the patient is awake. None of these alterations in the standard trapping film study are recommended, for in children particularly, they complicate the study and add variables which unless carefully controlled might alter the results considerably. In a clinical study of this nature a larger number of cases would be preferable. However, despite considerable variety in the patients' urological conditions, results were relatively uniform, adding support to their reliability. SUMMARY
"Trapping" films obtained following retrograde pyelography were studied in 11 pediatric urological patients aged from 4 to 12 years.
In the dehydrated, anesthetized child with functionally normal upper urinary tracts, contrast medium injected into the renal pelvis at retrograde pyelography remained visible on x-rays (taken with the child still on the cystoscopic table) for 15 to 30 minutes and occasionally even longer. Drainage time longer than 30 minutes was noted in all patients with known upper urinary tract disease, and was attributed to either poor renal function, increased upper urinary tract volume secondary to existing or previous obstruction, or a combination of these factors. When "trapping" films were obtained with the patient in a "head-up" position, with the patient hydrated intravenously, or with the patient awake, sitting up and drinking, the normal upper urinary tract drained contrast material completely, as demonstrated with x-rays, in 15 minutes or less. Under similarconditions, the pelvis of the obstructed or compromised kidney took a variable time longer than fifteen minutes to drain completely. A standard trapping film study has been proposed; it is based on experience obtained with these patients and is recommended with the idea of standardizing a useful investigative procedure.
Vol. 87, No. 5 May 1962 Copyright© 1962 hy The Williams & Wilkins Co. Printed in U.S.A.
HOW L03'\G DOES IT TAKE A CHILD'S KIDNEY TO DRAIN AFTER RETROGRADE PYELOGRAPHY? FREDERICK C. MARSHALL* From the Columbia-Presbyterian Medical Center, the Squier Urological Clinic, New York 32, N. Y.
The "trapping" film, or "trap" film is an x-ray taken to demonstrate any delay in the emptying of contrast medium from the renal pelvis and ureter into the bladc18r. Trapping films are usually obtained at intervals following retrograde pyelography, but can also be obtained following cystography, if V8sicoureteral reflux occurs. Delay in emptying of the contrast material from the upper tracts into the bladder is considered to indicate obstruction of the renal pelvis or ureter, or impaired function of the kidney. Such a delay is call8d "trapping" (of contrast medium) in the pelvis and/or ureter. In children, a comparison of successive examinations of this type may aid in ascertaining whether an obstructive condition with renal deterioration is progressive, stable, or improving. Important as the trapping film can be, there appears to be no standard technique for making such studies. No clinical work could be found in the literature which presented normal and abnormal renal drainage times, the factors ,vhich alter drainage time, and the conditions under which drainage time should be evaluated. Complete emptying of the renal pelvis and ureter in 5 to 10 minutes has been demonstrated in anesthetized children (ages not stated) with normal urinary tracts. 1 In the same study, several children with megaureter and reflux, but without obstruction, demonstrated complete emptying of the renal pelvis and ureter in 6 to 10 minutes following cystograms which were presumably done while the patients were awake. The author did not give the ages of his patients but stated that he felt his findings supported those of Campbell on this subject. Campbell 2 states, in describing "trapping" studies, " ... no attern.pt is made to empty the Accepted for publication October 3, 1961. This work was supported in part by a gift from the Goldman Fund. * Present address: Baker Clinic, Edmonton, Alberta, Canada. 1 Stephens, F. D.: Megaureter. Austral. & New Zealand J. Surg., 23: 197-205, 1954. 2 Campbell, M. F.: Clinical Pediatric Urology. Philadelphia: W. B. Saunders Co., 1951, p. 95. 7:30
injected pelves and ureters by catheter following retrograde pyelography. "Following removal of the catheters, the child is kept on the table for 5 to 10 minutes for a trap film exposure to determine the rate and extent of ureteral and pelvic emptying; in short, for evidence of upper tract urinary stasis. In an infant the x-ray exposure is made 5 minutes after the catheters are withdrawn, and in older children after 6 to 10 minutes, according to age. Trap films may show pelvic retention of medium 2 or 3 hours after pyelography and data obtained by this technique arc often the most valuable of the examination. For this reason trap films should always be made following retrograde pyelograms." Later in his book, discussing excretory urography, Carnpbell3 states: "As determined urographically, the pelvis of a child normally empties itself in 2 to 4 minutes, sometimes in 30 to 40 seconds. The urographic demonstration of fluid retention after 5 minutes may be considered pathologic retention. Delayed pelvic emptying time may be readily demonstrated by excretory urography and has the added advantage of 1) bilateral observation for comparison, and 2) absence of instrumental interference with normal pelviurcteral activity." \Ve would conclude from the foregoing statements that the emptying time of the normal renal pelvis and ureter is less than 10 minutes, and usually less than 5 minutes, and that the younger the child, the shorter the emptying time. Details about the age of the patients tested, and whether anesthesia was given, were not included in all instances by these authors. Since continuing excretion of contrast medium occurs in excretory urography, information on renal pelvic drainage time obtained by this technique ,mule! seem to be only of a very general nature. The present study was undertaken to determine the time required for the contrast medium used in retrograde pyelography to drain com3 Campbell, M. F.: Clinical Pediatric Urology. Philadelphia: W. B. Saunders Co., 1951, p. 147.
RETHOGRADE PYffiLOGRAPHY
with :1 variety of anesthetic a.gents. In rnost the Butkrfirkl size l fiF double rhildnm's cystourethroscope 1vas used to the: bladder and to introduc:e one EiF or two 4T uretcrnl cmtheters. The ddail~ of the films varied with 1:acl1 1mticnt ancl obtainer! depemliug on thr· circmnst:mcc·s of
pl,~tel)' to the hlaclder in u, g:rnup of c:hilclnm with normal and almorrnal trnet~, and under a, of conditiorn; 1.rith and witliout general ,t.ue:.;tlicsia, At the l:rological Clinic al! anesthesia 11cdiatrir: for c:ystoscopy, except in 1mu8u:1l cirnnnstances,
C.H,88.
METHOD
The patients formed fi groups: · Three ,rnd Group nornml upper anc;sthetized, 1vith urinary trads undenn:nt r:yctosC'OJlY and bilateral or unilateral rdrogradc pyelograph~' m lhc supine pmition. Fifteen :md ;30 minute ("trapping") films \H:l"l, taken with tlic still on the table, the legs den1kcl in stirrupc, Gronp B: Two patients, deh)'clratecl aucl rnH','i tlwtizecl, with unilateral upper tract abnorrnnli, ties m1denvent (oystoscop.\' \\"ith bil::itPral unilateral retrograde pyelogn1.phy in th" position, Fift1::m1 and ;30 minute film,,
1) Pat:ients, Patients were sdcd,ed for study if there was a clinical indication for retrograde ) if the cl1ild was in good general health and old enough that the, slight prolongation of ancsthcRia ncc'l:ss,uy for tlw study would not be detrimental. Eleven µatif'.nts 11 ere studied: 4 girls and 7 boys, aged 4 to 12 yearn, ,vith u variety of urological conditiorrn, 2) Pro1:eilu1'e, Patic;nts 1n:rc; dcbydrntccl for fi to 12 hours clepc;ndiug on age and the time of cvstoscopy. Al I patient;, receiYecl routine preJ ncsthetic: medication and hurl general anesthe~ia,
TABLE
Group
IVP
Diagnosis
Enuresis.
/L Functionally normal upper trads. Anes-
Ure.th . stenosis. }En. R & L reflnx. Neurugenic bladder.
t.heti1.ccL Dehydrated. Snpine.
B. Unilateral abnormality. ,,\nesthci. ized. Dehydrated, Supine. C. Ftu1ctiona.ll:\' nornlal.
L
Nonnal, wit.Ji Jargc bladder. No nppfT tract dilatation. Enlarged L renal pelvis.
R. rgp .. incomplete in 1.5 m. cr,1n-nletc in ;;o rn. R & L rgp~; R nearly complete in 15 m. L ineornplctl' in 2 hr,-,
Enuresis.
Minor anomaly, L upper calyx.
R
Post, R. herninephrce-
R post-op kidney. L n'duplication.
R & L rgps; anesth. --H. iucoinplete in 30 m., L near complete in 15 m · mYake--R co111plete in ;H)--{iO m., L cornplet.e iu 15 n1 R rgp; auesth., ineumpldc in :.rn rn awake, incornplete in (iO lll.
Post-vyclopbst,y (left)
F
023U75
F
R rgp; incomplete in 15 m. R & L rgps; R nuarly comr,!dc i.11 20 m. L complete in 20 n1. H. & L rgps; bilaterally incompi0tt' .i.n 15 m. hut complete in 30 rn.
R nrcteral strictnre (mild).
1:J\J2D5.J,
R upper tract, reduplication. Normal
Study Done: Drainage TinH.:
Ancst.l1ct,ized. Dehydrated, then n.wake &, I1ydratf'd.
D.
r:-- nilatcral abnormal-
12
ity. )._nesthetized &
ton1)·.
dehydrated, then a.wake & hydrated.
:u u
Congenital R mega-
ureter.
E. Fnnctionally normal. Anesthetized. Hy-
R hydroureteroncplnosis (mild)
maht:r. Anl~stbetized. Dcl1y-drated. Hc,Hl up.
218-!3:)
& L l'g;ps: incomplete_> in [) m, nearly complete in 10 rn., cotnpl.(~tt i.n 15 rn.
M
Post-renal tutJerculosis.
Nonnal.
R
M l1
Post-acute c:ystitis.
Normal.
R & L rgp1:,; incomplek in 5 rn. lt111 pine), cornplcte i.n 10 rn. (hea.d 11p). R & L rgps; R. incomplete in 16 (head np) L romplet.e in 15 rn (head-npJ.
drated.
F. Bi- or uuilaL abnor-
& L rgps; :-rnestbetized incorn· pletc in :rn Ill.. awake-- ·curuplc~i.<'. i.r, 15 m
H marked, L min.
H. l.i-:,,,·clroureternne ..
phrosis.
,\l.ibreviatlons; R = riglir.; L = left; rgp = retrogra
732
FREDERICK C. MARSHALL
_FIG. 1. Retrograde pyelograms, with 15 and 30 mmute delayed films on patient No. 1493703 under ge_neral anesthesia .. Above, normal upper tracts. M1dd)e, partial dramag_e. Below, complete drainage bilaterally, at 30 mmutes.
were obtained with the patient still on the cystoscopy table, and in one case a 2 hour delayed film was taken after the patient had returned to the ward. Group C: One patient, dehydrated and anesthetized, with functionally normal upper urinary tracts, underwent bilateral retrograde pyelography and 15 and 30 minute delayed or "trapping" films. Ureteral catheters were replaced and taped to an indwelling Foley catheter. Three hours later, with the child then able to sit, and stand, and after taking some fluids, the retrograde pyelograms with delayed films were repeated. Group D: Two patients, dehydrated and anesthetized, with unilateral upper tract abnormalities had unilateral or bilateral retrograde pyelography, with in one case 20 minute, and in the other 15 and 30 minute delayed films. Ureteral catheters were then replaced, as in group D, and the pyelogram with trapping films was repeated after several hours.
_FIG. 2. Retrograde pyelograms, with 15 and 30 mmute delayed films taken on patient No. 236625, u_nder general anesthesia. Above, normal right kidney, and large left kidney and pelvis following pyeloplasty. Middle, 15 minute delayed film shows n'°'.arly complete drainage on the right. Below, 30 mmute delayed film shows complete right drainao-e and severe 'trapping' on the left. Contrast mediu~n was still visible in this abnormal kidney 2 hours following pyelography.
Group E: One patient, anesthetized and hydrated intravenously, with functionally normal Llpper urinary tracts following renal tuberculosis underwent bilateral retrograde pyelography and 5, 10 and 15 minute delayed or "trapping" films were taken. Group F: Two patients, dehydrated and anesthetized, one with normal and the other with abnormal upper urinary tracts, had bilateral retrograde pyelograms done, and while still anesthetized, were placed in a position with the superior part of the body elevated to approxi-
HETROGRADJ~ PYELOGRAJ'HY
.Fm. 3. X-rays taken , a'.1-d 15 minutes following retrograde pyclography in pn1,icnt i\o, 1392954 several hours after (patient awake). a, ."\ ormaI appearing left kidney, on rc'1:rog;n1d1) pyelogrmn. b, Fifteen uu,rncc,,o later, complete drainage. ·· ·
mately :30 degrees above the horizontal (30 degree position) while 5 and 10, or 15 minute films were taken. RESUL'l':S
Table I summarizes the pati<,nts according to with age, sex, diagnosis, excretory llrogrnphic findings, and the time required for the upper tracts to drain following retrograde
groups,
pydography nnder test conditions. A. Films of the ::i c)hilclren in this group demonstrated that following retrograde pye]ography, with the patient dehydrated, anes-
that under rnnditions ~imilar to tbosc' in gro11p A, a relati\ el,v minor and minimally obstrnctiw 0
anomaly could prolong complete upper trad, drainage b()yond ;30 minutes, and that tlw obstrncted part of the) collecting .system take slightly longer than 30 minutes to draiu completely. ·whe,n tlie patient was mrnkt,, hydrated ancl sitting up, howC\cr, and retrngrade pyelography ,i-as clone through a catheter left indwelling at cystoscopy, the contrast inc-· clium drained to the blaclder in le:,:~ than 15 minutes (fig. :3). D. Films of these 2 r:hildren demonstrated that following retrograde ffith the patient dehydrated and am'st!wtizeC:, the normal upper tract drainage time wn::: bet\l'een 15 and 30 minutes. When the was awake, ac:tivc and hydrated, tlw normal upper tract drainage time following pyel ogra Jihy using ca thetcrs inserted at, c_rnto~eopy was less than 15 minutes. ,\lmornrnl upper LJrinary tracts took longer to drain than Llw normal upp<)r trads in both case8, In the first patient a poorly functioning right kidne:' follow-
thetized, and wpine on the cystoscopy table, contrast medium drained cornpletcly from the normal upper urinary trac:t to the bladder m between 15 and :30 minutes, as indicated dcla,vcd x-rays (fig. l). Group B. Films of the 2 patients in this group clemonstratecl that under conditions similar to those in group >\, nppe,r urinary tract abnormali-ties might or might not prolong clrainag<) time beyond the normal 15 to 30 minutes, depending on the nature of the abnormality. The first patient with a mild right ureteral stricture emptied (:ontrast material completely from his right kidney between L5 and ::io minutes. The
ing hcrninepbrectomy had drained by ;30 minutes during anesthesia, and drained c:ompl<'tely ,Yith the patient
second patient with a large left renal pelvis fol-·
between 30 and f-iO minutes. The second
lowing a pycloplasty dirl not empty contrast material r:ompletely from that kidney 2 hours, while his normal kiclne,1- hacl nearly completely drained 15 minutes (fig. 2). C. Films of this patient demonstrated
with a congenital megalourPkr, did not empty his kidney and ureter by 1 hour, e\"t'n awake (fig. 4). E. The films of thiH cbild (fig. ;S) demonstrated that under conditions similar to those in
734
FREDERICK C, MARSHALL
Fm. 5. X-rays taken immediately, and 10 minutes following retrograde pyelography in patient ~ o. 156483 under general anesthesia, and hydrated intravenously. Above, pyelograms show essentially normal upper tracts; right side is slightly overdistended. Below, 10 minutes later, there is complete drainage on left, and nearly complete drainage on right. Fifteen minute delayed film showed complete drainage bilaterally. Fm. 4. Retrograde pyelograms and delayed films on patient No. 023975. With patient dehydrated and anesthetized, retrograde pyelograms, a, demonstrate deformed right renal pelvis following heminephrectomy, with normal left upper half of double kidney. b, Fifteen minutes later, partial drainage on normal left side. c, Thirty minutes later, left kidney has drained completely, but abnormal right kidney still contains contrast medium. Later, with patient awake and hydrated, retrograde pyelograms d, and 15 minutes later, delayed films e, show complete drainage on left side, but trapping on right. group A, but with intravenous hydration, the drainage time of functionally normal upper urinary tracts could be decreased from the usual 15 to 30 minutes to between 10 and 15 minutes. Group F. Films of these 2 patients demonstrated that under conditions similar to those in group A, but with the patient in the 30 degree "head-up" position, the drainage time of essentially normal upper urinary tracts following retrograde pyelography could be decreased to less than 15 minutes, in the anesthetized patient.
The second patient in this group, with marked vesicoureteral reflux on the right side, did not empty that abnormal upper tract by 15 minutes, even though the "head-up" position was used (fig. 6). DISCUSSIOK
The "trapping film" is one of a group of studies with which the function of the upper urinary tracts can be evaluated. If vesicouretera] reflux occurs, delayed or trapping films obtained following voiding cystourethrography or with the urethral catheter open following cystography, will demonstrate how rapidly urine can drain from the renal pelvis and ureter to the bladder. vVhcn the vesicoureteral valve is competent, the cystogram gives no information about the upper urinary tracts. If cystoscopy and retrograde pyelography are necessary in such cases, then "delayed" or "trapping" films are easily obtained. The interpretation of such films depends considerably upon their being done according to a
RETROGRADE PYELOGRAPHY
Fm. 6. Retrograde pyelograms and 15 minute delayed film on patient No. 1285902 under general anesthesia. Above, film shows normal left kidney, and pyelocalyectasis on right secondary to vesicoureteral reflux. Below, with patient in 'head-up' position, 15 minute delayed film shows complete drainage on left, and trapping on abnormal right side. standard technique with a knowledge of what normal and abnormal drainage times are and of the factors that can alter the time required for the upper urinary tract to drain completely to the bladder. The rate of drainage of urine from the upper urinary tracts to the bladder depends upon several factors; an attempt to measure this rate by introducing a radiographic medium through a catheter into the renal pelvis, then taking a series of x-rays with the patient either anesthetized or awake adds still further variables. The most important factors which influence the study are: Urinary output. The output of urine is decreased in advanced renal parenchymal disease, renal arterial obstruction, dehydration, anesthesia, and shock. Dilution of the radiographic material introduced by retrograde pyelography, to the point where it is no longer visible in the renal pelvis on x-ray, depends upon the urine flow rate, and variation in this rate will increase
735
or decrease the drainage time as demonstrated by trapping films. Volume of the collecting system. The volume of the renal pelvis and ureters is increased in nearly all upper tract obstructive conditions, and if urinary output remains unchanged, it will take a correspondingly longer time for introduced contrast medium to be "cleared" to the bladder. Obstruction. Obstructive conditions in themselves probably do not delay drainage of the upper tracts except as they produce alterations in urine formation rate, and increase in the volume of the pelvis and ureter. Gravity. Most contrast media used in urology are denser than urine and this fact, together with the possibility that gravity speeds upper tract drainage when the body is upright, may explain the distinctly more rapid upper tract drainage, which the semi-vertical position produced, as documented in this study. Age. It is probable that the high urine volumes of infants in relation to their body weights, and therefore to the size of their urinary collecting systems, make for a rapid upper tract drainage time, as Campbell 2 has stated. No information in this area has been obtained in this study, as our youngest patient was 4 years old. As a result of experience gained in obtaining the "trapping" films described in this paper, the following standard trapping film study is suggested for children in whom cystoscopy is done with general anesthesia. 1) Child is dehydrated for 6 to 12 hours prior to cystoscopy, depending on age. 2) General anesthesia is given, using intravenous fluids only as necessary. 3) Cystoscopic examination is made of the bladder and urethra. 4) Retrograde pyelography is performed in the usual way and the ureteral catheters are withdrawn from the ureters. 5) If the retrograde pyelograms are satisfactory, x-rays are obtained 15 and 30 minutes following the initial retrograde injection, these being the 15 and 30 minute delayed or "trapping" films. Note: The patient may be awakened from anesthesia following the 15 minute film, but should be kept on the cystoscopy table in the supine position with legs in the stirrups until the 30 minute film is obtained. 6) If contrast medium is still visible in the renal pelvis on the 30 minute film, then further
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FREDERICK C. MARSHALL
delayed films should be ordered for 1 or 2 hours and even 24 hours if indicated. The standard trapping film study just outlined may be altered to decrease the length of anesthesia by a) intravenous hydration prior to anesthesia, b) tilting the head of the cystoscopic table up to a 30 degree angle with the horizontal following withdrawal of the catheters, or c) leaving the ureteral catheters in place, taped to a urethral Foley catheter and obtaining retrograde pyelograms with delayed films 3 to 4 hours later when the patient is awake. None of these alterations in the standard trapping film study are recommended, for in children particularly, they complicate the study and add variables which unless carefully controlled might alter the results considerably. In a clinical study of this nature a larger number of cases would be preferable. However, despite considerable variety in the patients' urological conditions, results were relatively uniform, adding support to their reliability. SUMMARY
"Trapping" films obtained following retrograde pyelography were studied in 11 pediatric urological patients aged from 4 to 12 years.
In the dehydrated, anesthetized child with functionally normal upper urinary tracts, contrast medium injected into the renal pelvis at retrograde pyelography remained visible on x-rays (taken with the child still on the cystoscopic table) for 15 to 30 minutes and occasionally even longer. Drainage time longer than 30 minutes was noted in all patients with known upper urinary tract disease, and was attributed to either poor renal function, increased upper urinary tract volume secondary to existing or previous obstruction, or a combination of these factors. When "trapping" films were obtained with the patient in a "head-up" position, with the patient hydrated intravenously, or with the patient awake, sitting up and drinking, the normal upper urinary tract drained contrast material completely, as demonstrated with x-rays, in 15 minutes or less. Under similarconditions, the pelvis of the obstructed or compromised kidney took a variable time longer than fifteen minutes to drain completely. A standard trapping film study has been proposed; it is based on experience obtained with these patients and is recommended with the idea of standardizing a useful investigative procedure.