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Renal transplantation I. Use of donor organs with multiple vessels
RENAL
TRANSPLANTATION
I. Use of Donor
Organs with Multiple
L. H. BANOWSKY,
b1.D.
D. I?. SIEGAL,
Mc1.D.
C. B. HEWITT,
M.D.
B. H. STEWART,
Vessels
R. A. STRAFFON, M. 0.
bIvl.D.
MAGNUSSON,
W. E. BRAUN,
,I;I.D.
M.D.
M.D.
From the Department Cleveland, Ohio
of Urology,
Cleveland
Clinic,
Cleoelantl Clinic experience in transplanting 46 kidneys with multiple vessels is reported. Suggested surgical techniques for the vascular anatomosis are recommended und long-term results offunction and complications are reported. These kidneys can be safely and effectively used frown both related living and cadaver donors. ...--~-.__
ABS?‘KACII’-?‘he
~11 centers performing kidney transplants are experiencing a shortage of donor organs. An increase in supply can be achieved by either increasing the number of donors or by utilizing donors already available more efficiently. Ideally, the surgeon should be technically able to transplant all harvested kidneys. While this may not be the case for a variety of reasons, he should strive never to discard kidneys for anatomic or technical reasons. Kidneys having multiple vessels should not be rejected for transplantation for this reason alone. The ability to transplant these kidneys successfully increases the absolute number of donors, by making available the related living donor with bilateral multiple arteries, and enabling the surgeon to utilize available cadaveric organs more effectively. Because of the technical problems involved with kidneys with multiple vessels, some surgeons are reluctant to use these organs in renal transplantation. This has been particularly true with related living donor kidneys in which the anatomic structure of the renal arterial supply is known preoperatively through arteriography. It has been our experience that proper handling of
these organs from related living and cadaver donors at both the time of donor nephrectomy and transplantation will produce good functional results. Unilateral multiple renal arteries occur in approximately 23 per cent of the population: lsp and bilateral multiple arteries in approximately 10 per cent. Thus, the number of potential related living donors is reduced by 10 per cent and the number of suitable cadaveric organs by a larger figure; if these kidneys are not used. The left kidney is more likely to receive its blood supply from multiple renal arteries. Most commonly, small renal vessels go to the lower
pole of the kidney. Tiny supernumerary arteries occur in the upper pole of the kidney as branches of the phrenic, main renal, or suprarenal arteries. These are generally of such small size as to be clinically unimportant in transplantation, aud are not considered here. The architecture of the renal veins is diKerent from that of the arteries. Multiple veins are less common. Duplication of the left renal vein is uncommon, however, division of the single vein in its course toward the vena cava is fairly conmon. The vein splits with one branch passing in
front of the aorta and the other behind, and the two branches terminate separately in the vena cava. Duplication of the right renal vein is more common than on the left and trebling occurs infrequently. Multiple renal vessels will, of course, be more frequently encountered with cadaver donors since both kidneys should be used. In the live donor, the anatomic structure of the renal arteries will be known prior to nephrectomy through the use of arteriography.
Material and Methods Prior to November 15, 1973, a total of381 renal transplants had been performed at the Cleveland Clinic Hospital, 46 (12 per cent) with multiple renal vessels requiring more than the usual or standard vascular anastomoses. Twenty-three of the 276 (8 per cent) of kidney transplants prior to January, 1971, had multiple vessels. Of the 105 transplants done since that time, 24 (23 per cent) have had multiple vessels. During the last twelve months 14 of 39 (35 per cent) had multiple vessels. There are two basic reasons for the increased use of kidneys with multiple vessels: (1) our pool of potential recipients is growing faster than the number of organs available for transplantation, and (2) techniques for dealing with these organs have been mastered so that results comparable to those using kidneys with single vessels have been achieved. Eighteen of the 47 kidneys with multiple vessels were obtained from living donors and 29 from cadaver donors. Forty-two of the kidneys had multiple arteries, of these, 14 were from living donors. Six kidneys had multiple veins of such size that it was believed that the smaller vessel could not be ligated leaving one vein intact for the anastomosis. One kidney had both double veins and double arteries requiring anastomoses. One kidney had three renal arteries and another had three renal veins. Both were from living donors. Another kidney from a cadaver donor had a renal artery aneurysm as well as double renal veins. The aneurysm was repaired prior to transplantation. This case will be described more fully in Part II. The transplants were performed by six different surgeons using various techniques, although the general approach was the same. The objective was to make the revascularization procedure as simple as possible and to keep the warm ischemia
644
time to a minimum, while achieving a high degree of vessel patency. Techniques Colnrnon ostiurn When the donor organs had two arteries of comparable size which were adjacent to each other, the most commonly used technique was to suture the two arteries together side by side to form a common ostium. This was done with the kidney cooled in iced saline, resulting in no increase in the warm ischemia time. This common ostium was then anastomosed end to end with the hypogastric artery. The technique of forming the common ostium is illustrated in Figure 1. Briefly, it is performed as follows: with the kidney immersed in the cooling solution, the two donor arteries are brought into suitable alignment. Medial incisions of comparable length are made in each artery. A 6-O cardiovascular suture is brought from the apex of the medial incision to the most proximal end of the artery. The kidney is turned over in the slush solution, and the posterior walls of the vessels are brought into view. The same procedure is followed on the posterior side of the vessels. In suturing the common ostium so formed to the hypogastric artery, great care must be taken to avoid leakage in the area where the vertical and horizontal suture lines merge. Advantages of this method are that it is technically easy to perform, only one arterial anastomosis with the recipient is required, the kidney can be kept cold during the initial side-to-side anastomosis and the final anastomosis is end to end, which is preferred. This technique was used in I9 patients in this series. End-to-end
and end-to-side
When two arteries were present, and widely separated from each other, or of significantly unequal size, the most commonly used technique was to anastomose the larger vessel to the hypogastric artery in the usual end-to-end fashion; the smaller vessel was then anastomosed end to side with external iliac artery (Fig. 2). After the venous anastomosis and the anastomosis of the larger of the arteries are complete, the vascular clamps on the hypogastric artery and the external iliac vein are removed, thus revascularizing most of the kidney. The external iliac artery is then secured proximal to the inguinal ligament and distal to the take-off of the
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/
VOLUME
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nal iliac crrteq.
FIGURE 3. Anustorn0si.s aorta lo recipient vessel.
o/rertal
arteries with cuifof
645
hypogastric artery. A small arterial window is made in a segment of the external iliac artery where the small vessel can be comfortably anastomosed without kinking. Prior to anastomosis, the smaller vessel is perfused with a small amount of cold perfusion solution, and the ipsilateral lower extremity is flushed with 30 cc. of 1 per cent heparin solution. End-to-side anastomosis is then accomplished with interrupted sutures of 6-O cardiovascular silk. Double-armed sutures are preferred so that each stitch may be taken from the inside of the vessel. Sutures are first placed in the superior and inferior apices of the arteriotomy, and the renal artery is brought into proper alignment. These sutures are then tied. The remaining sutures on each side are placed and left untied until all sutures on that side have been placed. Significant back bleeding usually does not occur from the smaller renal artery, but ifit does occur, it can be controlled with a small bulldog clamp. The advantage ofthis technique is that the main arterial and venous clamps can be removed and flow started through most of the kidney after the first arterial anastomosis is completed. This allows more time to be taken with the smaller artery without increasing warm ischemia time. This method was used twelve times in this series.
Multiple veins were handled in a similar manner. Small accessory veins can be ligated without risk. These patients are not included in this series. When double veins of approximately equal size were present, both veins were implanted to assure that an increase in intrarenal venous pressure would not occur. Often this could be done by taking a cuff of vena cava at the time of nephrectomy. This worked best when using the right kidney with shorter renal veins. With the left kidney, the longer renal vein could result in kinking and possible obstruction of the venous drainage. If a cuff of vena cava was not used, the vessels were usually sutured together to form a single ostium as shown for the arteries. In some cases the veins were implanted individually. If this approach was taken, the arterial anastomosis was done after the first venous anastomosis. Flow through the kidney was then established with the second vein clamped, and more time was available for the second venous anastomosis without increasing the ischemia time. Relative venous obstruction for the short interval of time necessary to do the second anastomosis did not produce harmful effects.
Other methods A number of other anastomotic techniques have been described with multiple arteries, and several were used in this seriese3 Double renal arteries can sometimes be anastomosed to the hypogastric bifurcation. This method was used earlier in the series but has not been used recently. There are several reasons for discontinuing its use: (1) variations in the anatomic structure of this vessel are frequent and may preclude its use, (2) it is frequently involved with atheromatous plaques; (3) both arterial anastomoses must be done before either arterial clamp can be removed, thus prolonging the warm ischemia time; and (4) because of the arrangement of the hypogastric artery branches, one of the anastomoses may be angulated more than is desirable. If the renal arteries are close to each other at their take-off from the aorta, a cuff of aorta should be removed with the arteries at the time of cadaver donor nephrectomy. Then a single endto-side arterial anastomosis can be made to the common or external iliac artery (Fig. 3). This should not be done with live donors because of the increased risk to the donor. If the take-off of the arteries are not close together, a cuff should still be taken with the smaller artery to make the anastomosis of this vessel easier.
lschemia
646
Results time
The ischemia time required for vascular anastomosis varied from twenty-two to one hundred thirty-three minutes. This was measured to the time blood flow was reestablished through the majority of the kidney and not necessarily to the time all anastomoses were complete. The longest time noted occurred in a patient in whom the original anastomosis had to be redone because of inadequate flow. The ischemia time in the majority of cases was between thirty and forty-five minutes. Average ischemia time excluding the long time noted was forty-two minutes. Data on ischemia time were not available for 6 patients. Arterial thrombosis There were no occlusions of the main renal artery. Angiograms were not obtained routinely, but were done postoperatively in 10 patients in whom vascular problems were suspected. In 7 cases the angiograms were normal, 1 showed an occluded polar vessel, and 2 showed partial stenoses of the smaller of two renal vessels. No allografts were lost because of arterial thrombosis. Hypertension Severe hypertension developed in the postoperative period in 1 patient only, the an-
UROLOGY
/ DECEMBER 1974 / VOLUME IV, NUMBER 6
giogran showing ;I 50 per cent stenosis of the lower pole artery. After some initial difficulty, Mood pressure control is good with antihypertensive drugs, and renal function is adequate three years postoperatively.
The blood supply to the upper ureter is derived primaril\~ from branches of the renal artery. WIWII ulultiple renal arteries are present, the ureteral vessels usually arise from the lower pole branch. It might be expected that ureteral complications would be more common in transplanted kidneys with multiple vessels if either the lower pole branch is simply ligated or if after it is anastomosed thrombosis occurs. This could produce ureteral ischemia with sloughing and leakage of urine. III this series, two early urine leaks occurred at the site of the ureteroneocystostomy. Devascularization with ru-eteral slough did not occur in either patient. These were both technical failures and were repairecl without difficulty. Neither graft was lost.
Acute renal failure due to ischemic injury could in kidneys be expected to occur more frequently with multiple vessels because of the longer time usually required to complete the vascular anastomoses. For our purpose, any patient who required one or more hemoclialyses postoperatively was considered to have acute renal failure. TWO patients with biopsy-proved hyperacute rejection were excluded. Using this as a criteria, acute renal failure occurred in 5 of 18 (28 per cent) kidneys obtained from living donors and in 17 of 27 (63 per cent) kidneys obtained from cadaver donors. Since Januar!,, 1972, only 4 of 12 (33 per cent) recipients of cadaver kidneys with multiple vessels have required dialysis. By way ofcomparison, the over-all incidence of acute renal finlure in the last 76 consecutive cadaver and live donor kidney transplants done at this Clinic is 18 per cent. In the majority of cases the renal failure was of short duration and required only one or two hemodialyses. Other factors contributed to the lower rate of acute renal failure achieved recently. Particularly important are better preparation of the donor prior to nephrectomy and more aggressive use of fluids and diuretic drugs in the recipients. Incidence of acute renal failure was also analyzed in relation to the type of arterial anas-
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tomosis employed when multiple reual arteries arc present. In the living donor group in which the method of suturing the two vessels together prior to anastomosis was used, only I of 5 patients required postoperative hemodialysis. However, in the cadaver group in which the same technique was used, hemodialysis was required in 10 of 12 patients. In the patients in whom the arterial anastomosis was made by suturing the larger renal artery to the hypogastric artery and the smaller artery to the external iliac artery, none of the 3 with live donor organs and 4 of the 8 with cadaver organs required postoperative hemodialysis. When other methods were used for the arterial anastomosis, 2 of 4 patients with live donor kidneys and 3 of 6 with cadaver kidneys required postoperative hemodialysis. From these data we cannot conclude that the method of anastomosis chosen is crucial.
Rer~al function Evaluation of postoperative renal function for the group of patients receiving live donor grafts revealed the serum creatinine for 10 of the 17 patients to be 2 mg. per 100 ml. or less at one month. Six additional patients had serum creatinine values between 2.1 mg. and 3.5 mg. per 100 ml. Ofpatients followed up for at least one year with a functioning allograft, 8 of 10 had serum creatinine values of 2 mg. per 100 ml. or less. One patient had a creatinine of4 mg. per 100 ml., and another required chronic dialysis because of poor renal function due to development of biopsy-proved glomerulonephritis in the transplanted kidney. One patient whose graft never functioned, but whose angiogram showed good vascular supply, was excluded from these figures. Evaluation of renal function at one month and one year for the patients receiving cadaver allografts revealed 14 of 23 patients had a serum creatinine of 2 mg. per 100 ml. or less after one month. Eight patients had serum creatinine values between 2.1 mg. and 4.4 mg. per 100 ml. One patient died of pneumonia and septic shock. Five kidneys were removed prior to one month because of rejection. All arteries were patent at the time of nephrectomy. Comment The frequent occurrence of multiple renal vessels requires an awareness of methods to deal with them. The scarcity of donor organs demands that
a7
they not be discarded or lost because of real or anticipated technical problems at the time of the surgical procedure. Kidneys with multiple vessels can be safely used if handled properly. In the living donor multiple vessels are denonstrated by angiography prior to nephrectomy. If unilateral multiple vessels are present in the living donor, the side with a single artery should be chosen for transplantation. In the 10 per cent of potential living donors with bilateral multiple vessels we believe that the kidneys can be used safely. In our experience the higher success rate obtained with related living donor transplants justifies the choice of these kidneys over those obtained from a cadaver donor. Proper management of the kidney with multiple vessels begins at the time of donor nephrectomy. In the cadaver donor this requires thorough exposure of the aorta and vena cava and removal of a cuff or an entire section of these vessels along with the kidneys. This will allow simple and rapid perfusion and leave adequate lengths of vessels available for the subsequent implantation regardless of the method chosen. In the living donor, cuffs of aorta should not be taken because of the increased risk to the donor. In these patients it is important to identify all renal vessels and dissect them to their origin to obtain as much length as possible at the time of nephrectomy. Little of the tissue around the renal hilum should be removed to avoid compromising the blood supply to the ureter. In the kidney with multiple arteries the ureter often receives its blood supply from the lower pole artery. Technically, the technique whereby the two vessels are joined to form a common ostium is much easier than other proposed techniques and requires no special surgical or optic instrumentation.3’4 It also has the two theoretic advantages of increasing the flow through the smaller vessel (Poiseuille’s law) and the final anastomosis with the hypogastric is end to end which also allows for maximum flo~.~ When possible, this is the preferred technique at the Cleveland Clinic because of its technical simplicity and the proposed theoretical advantages for obtaining maximum flow through the vessel. This technique has not received proper recognition. Small accessory veins can usually be ligated without risk. Larger veins require preservation and anastomosis to avoid the possibility of venous congestion. The technique used to manage multiple renal veins is identical to that described for multiple renal arteries. Often their implantation
648
can be facilitated by using a cuff of vena cava, particularly if the right kidney is being used. The left renal vein is usually too long to be used in this manner without producing kinking and partial obstruction. Results Several points deserve emphasis in evaluating the results of this series. Vessel thrombosis was not a cause of allograft failure in this series of kidneys with multiple renal vessels. Devascularization of the ureter due to inadequate blood supply did not occur. Although two early urine leaks did occur in the area of the ureteroneocystostomy, both responded well to secondary repair and were due to technical errors in performing the ureteroneocystostomy. Serious hypertension resulted in 1 patient in this series in whom a postoperative angiogram showed a partial stenosis of a polar artery. This complication has not been reported by others. 3,4 Hypertension did not occur in another patient whose angiogram showed a similar stenosis of one artery, nor did it occur in a third patient whose angiogram showed complete occlusion of a small polar vessel. 4. The incidence of acute renal failure requiring postoperative hemodialysis following the use of kidneys with multiple vessels can be expected to be higher than in cases in which single renal vessels are present. Undoubtedly, this is because of the increased manipulation and the longer ischemia times required before completion of all anastomoses. If, however, revascularization times are kept within reasonable limits, this should be reversible and ultimate renal functional results are good. We believe the results obtained justify the use of related living donor kidneys with multiple vessels and make mandatory the use of cadaveric kidneys with multiple vessels. Routine use of these organs will immediately increase the number of available donor kidneys. Summary A series of 47 renal transplants were evaluated in which multiple vessels were present in the renal allograft. Eighteen were kidneys from living donors and 29 from cadaver donors.
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Reversible acute renal failure occurred more frequently, and initial renal function was not as good as in kidnevs with single vessels, but at one month the functional results were comparable to those obtained from kidneys with a single artery and/or vein. Renal vessel thrombosis did not result in the failure of a single renal allograft. There were no instances of ureteral devascularization, and significant hypertension related to renal artery stenosis occurred in only 1 patient. 9500 Euclid Avenue Cleveland, Ohio 44106 (DR. BANOWSKY)
1. GOSS, C. 41.: Gray’s Anatolny. 27th ed.. Philxlrpl~i,~. Lea and Febiger, 1959. p. 682. 2. HOLLINSIIEAD, W. H.: .4natomy for Surgeons, 2nd rd.. New York, Harper and Row Publishers, Inc., 1971. vol. 2, p, 533. 0. BELZER, F. O., SCHWEIZER, R. T.. and Kox-NTZ. S. L.: Management of lnultiplf vessels in renal transplantation, Transplant. Proc. 4: 639 (1972). 4. SIMMONS.R. L.. TALLENT, &lM. B., KJELLSTRAND, C Lt., Kidney transplantation front livand NAJARIAN, J. S.: ing donors with double renal arteries. Surgery 69: 201 (1971). et al. : Management of nlultiple renal rj. UENDEZ. R., arteries in renal trarlsplantation. Urology 3: 409 (1974).
649
TRANSPLANTATION
I. Use of Donor
Organs with Multiple
L. H. BANOWSKY,
b1.D.
D. I?. SIEGAL,
Mc1.D.
C. B. HEWITT,
M.D.
B. H. STEWART,
Vessels
R. A. STRAFFON, M. 0.
bIvl.D.
MAGNUSSON,
W. E. BRAUN,
,I;I.D.
M.D.
M.D.
From the Department Cleveland, Ohio
of Urology,
Cleveland
Clinic,
Cleoelantl Clinic experience in transplanting 46 kidneys with multiple vessels is reported. Suggested surgical techniques for the vascular anatomosis are recommended und long-term results offunction and complications are reported. These kidneys can be safely and effectively used frown both related living and cadaver donors. ...--~-.__
ABS?‘KACII’-?‘he
~11 centers performing kidney transplants are experiencing a shortage of donor organs. An increase in supply can be achieved by either increasing the number of donors or by utilizing donors already available more efficiently. Ideally, the surgeon should be technically able to transplant all harvested kidneys. While this may not be the case for a variety of reasons, he should strive never to discard kidneys for anatomic or technical reasons. Kidneys having multiple vessels should not be rejected for transplantation for this reason alone. The ability to transplant these kidneys successfully increases the absolute number of donors, by making available the related living donor with bilateral multiple arteries, and enabling the surgeon to utilize available cadaveric organs more effectively. Because of the technical problems involved with kidneys with multiple vessels, some surgeons are reluctant to use these organs in renal transplantation. This has been particularly true with related living donor kidneys in which the anatomic structure of the renal arterial supply is known preoperatively through arteriography. It has been our experience that proper handling of
these organs from related living and cadaver donors at both the time of donor nephrectomy and transplantation will produce good functional results. Unilateral multiple renal arteries occur in approximately 23 per cent of the population: lsp and bilateral multiple arteries in approximately 10 per cent. Thus, the number of potential related living donors is reduced by 10 per cent and the number of suitable cadaveric organs by a larger figure; if these kidneys are not used. The left kidney is more likely to receive its blood supply from multiple renal arteries. Most commonly, small renal vessels go to the lower
pole of the kidney. Tiny supernumerary arteries occur in the upper pole of the kidney as branches of the phrenic, main renal, or suprarenal arteries. These are generally of such small size as to be clinically unimportant in transplantation, aud are not considered here. The architecture of the renal veins is diKerent from that of the arteries. Multiple veins are less common. Duplication of the left renal vein is uncommon, however, division of the single vein in its course toward the vena cava is fairly conmon. The vein splits with one branch passing in
front of the aorta and the other behind, and the two branches terminate separately in the vena cava. Duplication of the right renal vein is more common than on the left and trebling occurs infrequently. Multiple renal vessels will, of course, be more frequently encountered with cadaver donors since both kidneys should be used. In the live donor, the anatomic structure of the renal arteries will be known prior to nephrectomy through the use of arteriography.
Material and Methods Prior to November 15, 1973, a total of381 renal transplants had been performed at the Cleveland Clinic Hospital, 46 (12 per cent) with multiple renal vessels requiring more than the usual or standard vascular anastomoses. Twenty-three of the 276 (8 per cent) of kidney transplants prior to January, 1971, had multiple vessels. Of the 105 transplants done since that time, 24 (23 per cent) have had multiple vessels. During the last twelve months 14 of 39 (35 per cent) had multiple vessels. There are two basic reasons for the increased use of kidneys with multiple vessels: (1) our pool of potential recipients is growing faster than the number of organs available for transplantation, and (2) techniques for dealing with these organs have been mastered so that results comparable to those using kidneys with single vessels have been achieved. Eighteen of the 47 kidneys with multiple vessels were obtained from living donors and 29 from cadaver donors. Forty-two of the kidneys had multiple arteries, of these, 14 were from living donors. Six kidneys had multiple veins of such size that it was believed that the smaller vessel could not be ligated leaving one vein intact for the anastomosis. One kidney had both double veins and double arteries requiring anastomoses. One kidney had three renal arteries and another had three renal veins. Both were from living donors. Another kidney from a cadaver donor had a renal artery aneurysm as well as double renal veins. The aneurysm was repaired prior to transplantation. This case will be described more fully in Part II. The transplants were performed by six different surgeons using various techniques, although the general approach was the same. The objective was to make the revascularization procedure as simple as possible and to keep the warm ischemia
644
time to a minimum, while achieving a high degree of vessel patency. Techniques Colnrnon ostiurn When the donor organs had two arteries of comparable size which were adjacent to each other, the most commonly used technique was to suture the two arteries together side by side to form a common ostium. This was done with the kidney cooled in iced saline, resulting in no increase in the warm ischemia time. This common ostium was then anastomosed end to end with the hypogastric artery. The technique of forming the common ostium is illustrated in Figure 1. Briefly, it is performed as follows: with the kidney immersed in the cooling solution, the two donor arteries are brought into suitable alignment. Medial incisions of comparable length are made in each artery. A 6-O cardiovascular suture is brought from the apex of the medial incision to the most proximal end of the artery. The kidney is turned over in the slush solution, and the posterior walls of the vessels are brought into view. The same procedure is followed on the posterior side of the vessels. In suturing the common ostium so formed to the hypogastric artery, great care must be taken to avoid leakage in the area where the vertical and horizontal suture lines merge. Advantages of this method are that it is technically easy to perform, only one arterial anastomosis with the recipient is required, the kidney can be kept cold during the initial side-to-side anastomosis and the final anastomosis is end to end, which is preferred. This technique was used in I9 patients in this series. End-to-end
and end-to-side
When two arteries were present, and widely separated from each other, or of significantly unequal size, the most commonly used technique was to anastomose the larger vessel to the hypogastric artery in the usual end-to-end fashion; the smaller vessel was then anastomosed end to side with external iliac artery (Fig. 2). After the venous anastomosis and the anastomosis of the larger of the arteries are complete, the vascular clamps on the hypogastric artery and the external iliac vein are removed, thus revascularizing most of the kidney. The external iliac artery is then secured proximal to the inguinal ligament and distal to the take-off of the
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VOLUME
IV, NUMBER 6
nal iliac crrteq.
FIGURE 3. Anustorn0si.s aorta lo recipient vessel.
o/rertal
arteries with cuifof
645
hypogastric artery. A small arterial window is made in a segment of the external iliac artery where the small vessel can be comfortably anastomosed without kinking. Prior to anastomosis, the smaller vessel is perfused with a small amount of cold perfusion solution, and the ipsilateral lower extremity is flushed with 30 cc. of 1 per cent heparin solution. End-to-side anastomosis is then accomplished with interrupted sutures of 6-O cardiovascular silk. Double-armed sutures are preferred so that each stitch may be taken from the inside of the vessel. Sutures are first placed in the superior and inferior apices of the arteriotomy, and the renal artery is brought into proper alignment. These sutures are then tied. The remaining sutures on each side are placed and left untied until all sutures on that side have been placed. Significant back bleeding usually does not occur from the smaller renal artery, but ifit does occur, it can be controlled with a small bulldog clamp. The advantage ofthis technique is that the main arterial and venous clamps can be removed and flow started through most of the kidney after the first arterial anastomosis is completed. This allows more time to be taken with the smaller artery without increasing warm ischemia time. This method was used twelve times in this series.
Multiple veins were handled in a similar manner. Small accessory veins can be ligated without risk. These patients are not included in this series. When double veins of approximately equal size were present, both veins were implanted to assure that an increase in intrarenal venous pressure would not occur. Often this could be done by taking a cuff of vena cava at the time of nephrectomy. This worked best when using the right kidney with shorter renal veins. With the left kidney, the longer renal vein could result in kinking and possible obstruction of the venous drainage. If a cuff of vena cava was not used, the vessels were usually sutured together to form a single ostium as shown for the arteries. In some cases the veins were implanted individually. If this approach was taken, the arterial anastomosis was done after the first venous anastomosis. Flow through the kidney was then established with the second vein clamped, and more time was available for the second venous anastomosis without increasing the ischemia time. Relative venous obstruction for the short interval of time necessary to do the second anastomosis did not produce harmful effects.
Other methods A number of other anastomotic techniques have been described with multiple arteries, and several were used in this seriese3 Double renal arteries can sometimes be anastomosed to the hypogastric bifurcation. This method was used earlier in the series but has not been used recently. There are several reasons for discontinuing its use: (1) variations in the anatomic structure of this vessel are frequent and may preclude its use, (2) it is frequently involved with atheromatous plaques; (3) both arterial anastomoses must be done before either arterial clamp can be removed, thus prolonging the warm ischemia time; and (4) because of the arrangement of the hypogastric artery branches, one of the anastomoses may be angulated more than is desirable. If the renal arteries are close to each other at their take-off from the aorta, a cuff of aorta should be removed with the arteries at the time of cadaver donor nephrectomy. Then a single endto-side arterial anastomosis can be made to the common or external iliac artery (Fig. 3). This should not be done with live donors because of the increased risk to the donor. If the take-off of the arteries are not close together, a cuff should still be taken with the smaller artery to make the anastomosis of this vessel easier.
lschemia
646
Results time
The ischemia time required for vascular anastomosis varied from twenty-two to one hundred thirty-three minutes. This was measured to the time blood flow was reestablished through the majority of the kidney and not necessarily to the time all anastomoses were complete. The longest time noted occurred in a patient in whom the original anastomosis had to be redone because of inadequate flow. The ischemia time in the majority of cases was between thirty and forty-five minutes. Average ischemia time excluding the long time noted was forty-two minutes. Data on ischemia time were not available for 6 patients. Arterial thrombosis There were no occlusions of the main renal artery. Angiograms were not obtained routinely, but were done postoperatively in 10 patients in whom vascular problems were suspected. In 7 cases the angiograms were normal, 1 showed an occluded polar vessel, and 2 showed partial stenoses of the smaller of two renal vessels. No allografts were lost because of arterial thrombosis. Hypertension Severe hypertension developed in the postoperative period in 1 patient only, the an-
UROLOGY
/ DECEMBER 1974 / VOLUME IV, NUMBER 6
giogran showing ;I 50 per cent stenosis of the lower pole artery. After some initial difficulty, Mood pressure control is good with antihypertensive drugs, and renal function is adequate three years postoperatively.
The blood supply to the upper ureter is derived primaril\~ from branches of the renal artery. WIWII ulultiple renal arteries are present, the ureteral vessels usually arise from the lower pole branch. It might be expected that ureteral complications would be more common in transplanted kidneys with multiple vessels if either the lower pole branch is simply ligated or if after it is anastomosed thrombosis occurs. This could produce ureteral ischemia with sloughing and leakage of urine. III this series, two early urine leaks occurred at the site of the ureteroneocystostomy. Devascularization with ru-eteral slough did not occur in either patient. These were both technical failures and were repairecl without difficulty. Neither graft was lost.
Acute renal failure due to ischemic injury could in kidneys be expected to occur more frequently with multiple vessels because of the longer time usually required to complete the vascular anastomoses. For our purpose, any patient who required one or more hemoclialyses postoperatively was considered to have acute renal failure. TWO patients with biopsy-proved hyperacute rejection were excluded. Using this as a criteria, acute renal failure occurred in 5 of 18 (28 per cent) kidneys obtained from living donors and in 17 of 27 (63 per cent) kidneys obtained from cadaver donors. Since Januar!,, 1972, only 4 of 12 (33 per cent) recipients of cadaver kidneys with multiple vessels have required dialysis. By way ofcomparison, the over-all incidence of acute renal finlure in the last 76 consecutive cadaver and live donor kidney transplants done at this Clinic is 18 per cent. In the majority of cases the renal failure was of short duration and required only one or two hemodialyses. Other factors contributed to the lower rate of acute renal failure achieved recently. Particularly important are better preparation of the donor prior to nephrectomy and more aggressive use of fluids and diuretic drugs in the recipients. Incidence of acute renal failure was also analyzed in relation to the type of arterial anas-
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I)ECEItBEH 197-l / VOLUTSIE I\‘. NUMBER 6
tomosis employed when multiple reual arteries arc present. In the living donor group in which the method of suturing the two vessels together prior to anastomosis was used, only I of 5 patients required postoperative hemodialysis. However, in the cadaver group in which the same technique was used, hemodialysis was required in 10 of 12 patients. In the patients in whom the arterial anastomosis was made by suturing the larger renal artery to the hypogastric artery and the smaller artery to the external iliac artery, none of the 3 with live donor organs and 4 of the 8 with cadaver organs required postoperative hemodialysis. When other methods were used for the arterial anastomosis, 2 of 4 patients with live donor kidneys and 3 of 6 with cadaver kidneys required postoperative hemodialysis. From these data we cannot conclude that the method of anastomosis chosen is crucial.
Rer~al function Evaluation of postoperative renal function for the group of patients receiving live donor grafts revealed the serum creatinine for 10 of the 17 patients to be 2 mg. per 100 ml. or less at one month. Six additional patients had serum creatinine values between 2.1 mg. and 3.5 mg. per 100 ml. Ofpatients followed up for at least one year with a functioning allograft, 8 of 10 had serum creatinine values of 2 mg. per 100 ml. or less. One patient had a creatinine of4 mg. per 100 ml., and another required chronic dialysis because of poor renal function due to development of biopsy-proved glomerulonephritis in the transplanted kidney. One patient whose graft never functioned, but whose angiogram showed good vascular supply, was excluded from these figures. Evaluation of renal function at one month and one year for the patients receiving cadaver allografts revealed 14 of 23 patients had a serum creatinine of 2 mg. per 100 ml. or less after one month. Eight patients had serum creatinine values between 2.1 mg. and 4.4 mg. per 100 ml. One patient died of pneumonia and septic shock. Five kidneys were removed prior to one month because of rejection. All arteries were patent at the time of nephrectomy. Comment The frequent occurrence of multiple renal vessels requires an awareness of methods to deal with them. The scarcity of donor organs demands that
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they not be discarded or lost because of real or anticipated technical problems at the time of the surgical procedure. Kidneys with multiple vessels can be safely used if handled properly. In the living donor multiple vessels are denonstrated by angiography prior to nephrectomy. If unilateral multiple vessels are present in the living donor, the side with a single artery should be chosen for transplantation. In the 10 per cent of potential living donors with bilateral multiple vessels we believe that the kidneys can be used safely. In our experience the higher success rate obtained with related living donor transplants justifies the choice of these kidneys over those obtained from a cadaver donor. Proper management of the kidney with multiple vessels begins at the time of donor nephrectomy. In the cadaver donor this requires thorough exposure of the aorta and vena cava and removal of a cuff or an entire section of these vessels along with the kidneys. This will allow simple and rapid perfusion and leave adequate lengths of vessels available for the subsequent implantation regardless of the method chosen. In the living donor, cuffs of aorta should not be taken because of the increased risk to the donor. In these patients it is important to identify all renal vessels and dissect them to their origin to obtain as much length as possible at the time of nephrectomy. Little of the tissue around the renal hilum should be removed to avoid compromising the blood supply to the ureter. In the kidney with multiple arteries the ureter often receives its blood supply from the lower pole artery. Technically, the technique whereby the two vessels are joined to form a common ostium is much easier than other proposed techniques and requires no special surgical or optic instrumentation.3’4 It also has the two theoretic advantages of increasing the flow through the smaller vessel (Poiseuille’s law) and the final anastomosis with the hypogastric is end to end which also allows for maximum flo~.~ When possible, this is the preferred technique at the Cleveland Clinic because of its technical simplicity and the proposed theoretical advantages for obtaining maximum flow through the vessel. This technique has not received proper recognition. Small accessory veins can usually be ligated without risk. Larger veins require preservation and anastomosis to avoid the possibility of venous congestion. The technique used to manage multiple renal veins is identical to that described for multiple renal arteries. Often their implantation
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can be facilitated by using a cuff of vena cava, particularly if the right kidney is being used. The left renal vein is usually too long to be used in this manner without producing kinking and partial obstruction. Results Several points deserve emphasis in evaluating the results of this series. Vessel thrombosis was not a cause of allograft failure in this series of kidneys with multiple renal vessels. Devascularization of the ureter due to inadequate blood supply did not occur. Although two early urine leaks did occur in the area of the ureteroneocystostomy, both responded well to secondary repair and were due to technical errors in performing the ureteroneocystostomy. Serious hypertension resulted in 1 patient in this series in whom a postoperative angiogram showed a partial stenosis of a polar artery. This complication has not been reported by others. 3,4 Hypertension did not occur in another patient whose angiogram showed a similar stenosis of one artery, nor did it occur in a third patient whose angiogram showed complete occlusion of a small polar vessel. 4. The incidence of acute renal failure requiring postoperative hemodialysis following the use of kidneys with multiple vessels can be expected to be higher than in cases in which single renal vessels are present. Undoubtedly, this is because of the increased manipulation and the longer ischemia times required before completion of all anastomoses. If, however, revascularization times are kept within reasonable limits, this should be reversible and ultimate renal functional results are good. We believe the results obtained justify the use of related living donor kidneys with multiple vessels and make mandatory the use of cadaveric kidneys with multiple vessels. Routine use of these organs will immediately increase the number of available donor kidneys. Summary A series of 47 renal transplants were evaluated in which multiple vessels were present in the renal allograft. Eighteen were kidneys from living donors and 29 from cadaver donors.
UROLOGY
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DECEMBER
1974
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VOLUME IV, NUMBER 6
Reversible acute renal failure occurred more frequently, and initial renal function was not as good as in kidnevs with single vessels, but at one month the functional results were comparable to those obtained from kidneys with a single artery and/or vein. Renal vessel thrombosis did not result in the failure of a single renal allograft. There were no instances of ureteral devascularization, and significant hypertension related to renal artery stenosis occurred in only 1 patient. 9500 Euclid Avenue Cleveland, Ohio 44106 (DR. BANOWSKY)
1. GOSS, C. 41.: Gray’s Anatolny. 27th ed.. Philxlrpl~i,~. Lea and Febiger, 1959. p. 682. 2. HOLLINSIIEAD, W. H.: .4natomy for Surgeons, 2nd rd.. New York, Harper and Row Publishers, Inc., 1971. vol. 2, p, 533. 0. BELZER, F. O., SCHWEIZER, R. T.. and Kox-NTZ. S. L.: Management of lnultiplf vessels in renal transplantation, Transplant. Proc. 4: 639 (1972). 4. SIMMONS.R. L.. TALLENT, &lM. B., KJELLSTRAND, C Lt., Kidney transplantation front livand NAJARIAN, J. S.: ing donors with double renal arteries. Surgery 69: 201 (1971). et al. : Management of nlultiple renal rj. UENDEZ. R., arteries in renal trarlsplantation. Urology 3: 409 (1974).
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