Abdominal aortic surgery and the left renal vein

Anatomical variants of renal veins: A meta-analysis of prevalence

The main aim of this article is to establish the actual prevalence of renal vein variations (circumaortic renal vein, retroaortic renal vein, double renal vein), and to increase awareness about them. To this purpose, we have performed a meta-analysis of prevalence, using the MetaXL package, We included 105 articles in the final analysis of prevalence, of which 88 contained data about retroaortic renal vein, 84 – about circumaortic renal vein, and 51 - about multiple renal veins. The overall prevalence for retroaortic renal vein was 3% (CI:2.4–3.6%), for circumaortic renal vein − 3.5% (CI:2.8–4.4%), and for multiple renal veins - 16.7% (14.3–19.2%), much higher on the right 16.6 (14.2–19.1%) than on the left side 2.1 (1.3–3.2%). The results were relatively homogenous between studies, with only a minor publication bias overall.

Anatomic variations of the renal vessels pertinent to transperitoneal vascular control in the management of trauma

BACKGROUND

Operative exposure and control of the renal vessels through a transabdominal retroperitoneal (TARP) approach has been advocated for emergency management of renal trauma. The pertinent anatomic variations of the renal vasculature have not been well described.

METHODS

In 190 cadavers, the renal vessels were examined. The first 20 cadavers were examined via TARP approach, and 170 cadavers were investigated after evisceration. The findings were interpreted as they might relate to the TARP approach to the renal pedicle.

RESULTS

The renal artery (RA) originated dorsally or inferiorly to the left renal vein (RV) in 70% of the cadavers on each side. Additional RAs emerging below the inferior mesenteric artery were present in 2.4% of cadavers on the right side and 1.8% on the left. Approach to the inferior vena cava (IVC) adequate for the management of trauma through the TARP approach was impossible, although it has been recommended in some research. The clinically significant incidence of variations was as follows: 47% multiple RAs, 13% multiple RVs, and 50% of at least 1 RA that coursed superior to the right RV on the right margin of the IVC.

CONCLUSION

Knowledge of the varied anatomy of the renal vessels facilitates a safe approach to the kidneys in trauma management. The varied and unpredictable anatomy of the renal vasculature requires prompt change when the TARP approach fails to provide access to the vessels. In such cases, the colon should be mobilized promptly. On the right side of the IVC, the vessels are located so as to require clamping together almost always.

Congenital anomalies of the inferior vena cava and left renal vein: implications during open abdominal aortic aneurysm reconstruction

Although uncommon and usually incidental findings on imaging or at operation, congenital anomalies of the retroperitoneal venous system, particularly those involving the inferior vena cava and left renal vein, can be troublesome and dangerous during open repair of abdominal aortic aneurysms (AAA). We have provided a retrospective analysis of our single tertiary institution experience with these anomalies during more than 2400 open AAA reconstructions in an effort to determine if preoperative identification of these vessels decreased venous injury and subsequent morbidity as well as offering a thorough review of the relevant embryology, anatomy, and technical approaches for each specified anomaly for the practicing vascular surgeon.

MR-angiographic diagnosis of an aberrant retroaortic left renal vein and review of the literature

MR-angiography is suitable for depiction of developmental vascular anomalies such as an aberrant left renal vein. We report MRA findings of one case of a retroaortic left renal vein and the review of the literature.

Left renal vein variations

The highly complex embryological development of the left renal vein compared to its right counterpart results in greater variations which are clinically significant. The study aimed to identify these variations and to document its incidence. Cadaveric study: 153 kidney pairs were harvested en bloc, dissected, 100 resin casts prepared and 53 plastinated; renal venography performed on further 58 adults and 20 foetal cadavers. Clinical study: (retrospective analysis): a) radiological study, 104 renal venograms; b) live related renal transplantation, 148 donor left kidneys; c) abdominal aortic aneurysm surgery, 525 patients. Total sample size: 1008. Renal collars observed in 0.3%; retro-aortic vein 0.5%; additional veins 0.4%; posterior primary tributary 23.2%, (16.7% Type IB; 6.5% Type IIB, cadaveric series, only). Our results differ significantly in incidence to that reported in the literature: renal collar 0.2-30%; retro-aortic vein 0.8-7.1%; additional renal vein 0.8-6%. Variations are clinically silent and remain unnoticed until discovered during venography, operation or autopsy. To a transplant surgeon, morphology acquires special significance, since variations influence technical feasibility of operation. Prior knowledge of circum-aortic vein is important when blood samples from suprarenal or renal veins are collected. Collar may provide developed collateral pathway immediately after surgery if renal interruption planned without awareness of its presence. Variations restrict availability of vein for mobilisation procedures. In aortic aneurysm repair, retro-aortic vein is important. During retroperitoneal surgery, the surgeon may visualise a pre-aortic vein but be unaware of an additional retroaortic component or a posterior primary tributary, and may avulse it while mobilising the kidney or clamping the aorta.

Ligation of the left renal vein in epm1-Wistar rats: functional and morphologic alterations in the kidneys, testes and suprarenal glands

OBJECTIVE

The ligation of the left renal vein (LLVR) in man is a controversial procedure in view of the risks of lesion to the renal parenchyma. With the objective of studying the morphologic and functional alterations caused by these lesions, we conducted experimental research with rats.

MATERIAL AND METHODS

64 male adult EPM1-WISTAR rats were used, divided into 8 groups-4 for LLRV and four for control. Each LLRV group and corresponding control group were sacrificed progressively on the 7th, 15th, 30th and 60th day after the initial surgery.

RESULTS

We found morphofunctional alterations only in animals that underwent LLRV in the four periods of sacrifice. The proteinuria creatinine in serum, testosterone in serum and serum corticosterone in serum showed practically no alteration in relation to the normal values for rats. Statistically significant severe histological lesions were found in the kidneys and testes of the LLRV groups. Lesions in the suprarenal glands were also present in these groups, but no sufficient to demonstrate statistical significance.

CONCLUSION

Based on these results we can conclude that the ligation of the left renal vein is a procedure of high risk in these animals.

Congenital anomalies of left renal vein and its clinical importance: a case report and review of literature

Detailed knowledge of the anatomy and anomalies of renal veins is necessary for retroperitoneal surgery and venographic procedures. According to Thomas (1970, Arch. Surg. 100: 738-740), the anomalies of renal veins are more frequent than estimated. The number of surgical procedures and radiologic examinations related to the retroperitoneum are increasing, and therefore pathologic conditions of the retroperitoneal area have been discussed more frequently. We report on a retroaortic left renal vein joining the left common iliac vein, discuss the embryology and clinical importance of renal vein anomalies, and give an overview on the relevant literature.

Retroaortic left renal vein in testicular cancer patient: potential staging and treatment pitfall

A 20-year-old man was diagnosed with a left mixed germ cell testicular tumor and clinical staging with computerized tomography suggested left para-aortic subhilar retroperitoneal adenopathy. The patient received 4 cycles of cisplatin, vinblastine and bleomycin chemotherapy but the mass in the left renal hilus area remained unchanged. Subsequent retroperitoneal lymphadenectomy revealed the mass to be a retroaoritc left renal vein type 2. Further confusion occurred during followup in differentiating this anomaly from recurrent neoplasm necessitating evaluation by magnetic resonance imaging. Retroaortic left renal vein represents a potential imaging pitfall in testicular cancer that may facilitate suboptimal staging, treatment and followup.

Does division of the left renal vein during aortic surgery adversely affect renal function?

Between July 1980 and July 1988, 478 consecutive patients underwent aortic aneurysm operations at Royal Prince Alfred Hospital. Renal function was assessed by measurement of serum creatinine levels. The left renal vein was divided in 28 (8%) of the 355 patients undergoing elective aneurysm resection. The mean immediate postoperative creatinine values were significantly higher after left renal vein division, 193 +/- 174 mumol/L, compared to 133 +/- 93 mumol/l for those whose left renal vein remained intact (p less than 0.05 by Mann-Whitney U test). After one month, serum creatinine levels had decreased but were still significantly higher in those patients in whom the left renal vein had been divided, 170 +/- 166 mumol/l, compared to those in whom it was left intact 109 +/- 49 mumol/l (p less than 0.05 by Mann-Whitney U test). The suprarenal aorta was cross-clamped in seven (25%) of the 28 patients in whom the left renal vein was divided, compared to 21 (6%) of the 327 with the left renal vein intact. A rise in creatinine level was observed after suprarenal aortic cross-clamping. The left renal vein was divided in 17 (14%) of the 123 patients having emergency surgery for ruptured aortic aneurysm, 61 (49%) of whom survived more than 30 days. The mean immediate postoperative creatinine values were significantly higher after left renal vein division, 426 +/- 277 mumol/l, compared to those in whom the vein was left intact, 178 +/- 136 mumol/l (p less than 0.05 by Mann-Whitney U test). After one month, serum creatinine levels were still significantly higher in those patients in whom the left renal vein had been divided. Although division of the left renal vein is a useful way to improve exposure of the juxtarenal aorta, the maneuver is associated with an adverse effect on renal function.

Division of the left renal vein during aortic surgery

Perirenal aortic exposure and control can be facilitated by division of the left renal vein (LRV), but only if adequate collateral venous drainage is present. When incremental elevations in LRV pressure were produced in nine dogs, we noted that left renal glomerular and tubular function (creatinine clearance, sodium retention, urine osmolality, and urine output) were virtually lost at pressures greater than 50 to 60 cm water. Between January 1967 and December 1989, 64 patients underwent LRV division during the performance of abdominal aortic aneurysm surgery (57 of 589 = 10%) or reconstruction for aortoiliac occlusive disease (7 of 506 = 1%). LRV stump pressures (LRVSPs) were measured in 44 of these patients and were less than or equal to 60 cm water in all but one instance. Ten of the 64 patients died, but none as a consequence of this maneuver. Post-operatively, all survivors had serial serum creatinine levels measured and either an intravenous pyelogram, renal scan, or arteriogram. One case of a non-functioning left kidney was identified. This occurred in the only patient who underwent re-anastomosis after LRV division. A LRVSP equal to or greater than 50 cm water and extreme venous distention after test clamping served as a contraindication to LRV division in seven other patients. We conclude that a LRVSP less than or equal to 50 to 60 cm water indicates that the LRV may be safely divided during juxtarenal aortic exposure. However, a pressure greater than or equal to 50 to 60 cm water suggests that LRV division should not be carried out unless absolutely essential and then only if right kidney function is known to be adequate.

Renal vein anatomy and its implications for retroperitoneal surgery

Because of its complicated embryological development, the anatomy of the renal veins shows extensive variability. A full understanding of the potential anatomical variations is imperative for retroperitoneal operations. Based on 4,520 retroperitoneal computerized tomography scans, anatomical studies of autopsy material of 354 unselected cases and intraoperative observations made during 215 major retroperitoneal procedures, an attempt was made to define the most common renal vein variants and retrace their development during embryogenesis. Awareness of rare anomalies in urological and general surgery is crucial to prevent severe damage to the venous drainage of the left kidney, and because troublesome bleeding may occur during vascular and retroperitoneal oncological procedures in patients with unknown venous anomalies. We found the incidence of these variants to be 0.8 versus 1.7 versus 3.7%, respectively.

Massive haemorrhage caused by left renal vein ligation

It is common practice to ligate the left renal vein during aortic surgery. Although this does not usually lead to complications we report 2 patients in whom left renal vein ligation caused massive venous congestion of the kidney and major retroperitoneal haemorrhage. Nephrectomy was necessary to control the haemorrhage. In 1 patient immediate autotransplantation preserved renal function.

Division of the left renal vein. Guidelines and consequences

Ligation and division of the left renal vein is a reasonable safe procedure in selected patients when exposure of the perirenal aorta is crucial. This manipulation is possible because of extensive venous collateralization from the left kidney in man. Measurement of the venous stump pressure before ligation is recommended to assess the degree of collateralization, and the upper limit within which the vein may be divided safely is probably in the neighborhood of 60 cm of water. Reanastomosis of the vein is not necessary for preservation of renal function, although transient left renal dysfunction may occur. Examination of the urine and careful monitoring of renal function should be routine in the postoperative period. Intravenous urography and left spermatic venography later in the postoperative course can indicate the ultimate degree of function of the left kidney and the pathways of venous collateralization. Preservation of normal function and venous architecture at the renal hilum should be the rule.

Abnormal left renal vein. No barrier to Warren shunt

The purpose of the distal splenorenal shunt is to provide decompression of gastroesophageal varices while avoiding insult to the diseased liver. However, the technical difficulty of the operation has prevented widespread application of the procedure. It is important, therefore, that the technical problems an hazards of the operation continue to undergo analysis. This report has described successful establishment of a Warren shunt in three patients with abnormalities of the left renal vein. Previous left nephrectomy or an anomaly of the left renal vein does not preclude the use of the distal splenorenal shunt in the treatment of variceal hemorrhage.