Inosine: alternative or adjunct to regional hypothermia in the prevention of post-ischemic renal failure?

Inosine administered into the renal artery improves renal ischemic tolerance. The study was designed to establish the limitations of this measure by comparing its effectiveness with that of regional hypothermia and to test the possibility of combining inosine and hypothermia in prolonged renal hypothermia. In uninephrectomized dogs, the remaining kidney was subjected to 2 h of ischemia under inosine protection; perfusion cooling, or no protection (experiment A), or to 90 min of warm ischemia plus inosine plus 90 min of cold ischemia; 90 min of warm plus 90 min of cold ischemia, or 180 min of cold ischemia (experiment B). Whereas perfusion cooling reliably prevented permanent loss of renal function even after 180 min of ischemia, inosine was clearly inadequate for protection against warm ischemia exceeding 90 min, but effective in shorter periods of ischemia with some unreliability in borderline cases. Inosine protection can be combined with hypothermia in a sequential manner if extended ischemia becomes necessary unexpectedly. For clinical use, however, it seems safer to commence with hypothermia after 60 min of inosine-protected warm ischemia. Simultaneous balloon occlusion of the renal artery and transcatheter perfusion cooling facilitates the clinical applicability of these results.

Transrenal ureteral embolization

Transrenal closure of the ureter with butyl-2-cyanoacrylate using adjuvant balloon catheter occlusion was successfully performed for the palliative management of inoperable vesicovaginal and vesicosacral fistulas in 3 patients. Unilateral percutaneous nephrostomy provided supravesical urinary diversion as well as access for permanent embolization of the ureter. The contralateral kidney was nonfunctional in 2 patients. In the third, in addition to unilateral ureteral occlusion, the contralateral kidney was defunctionalized by embolization of the renal artery ("radiological nephrectomy") to avoid the need for bilateral nephrostomy drainage.

The metabolic situation in ureterosigmoidostomy

At reexamination 67 patients with ureterosigmoidostomies showed no significant alteration of their acid-base and electrolyte metabolism as compared to the preoperative situation and 39 patients with a colonic conduit. If required these patients had received an oral alkali substitution therapy; this proved to be necessary as a permanent measure only in cases with functional and morphological defects of the upper urinary tract. Spells of hyperchloremic acidosis had occurred in 13 patients during the follow-up period and always coincided with attacks of acute pyelonephritis and renal deterioration, often accompanied by irregularities in the substitution. Obviously metabolic problems arise only with a deteriorating urinary tract and timely discovery and treatment of these patients is the main task of the supervising doctor. Although the metabolic imbalances usually respond promptly to an adaptation of the substitution therapy, patients with a predamaged upper urinary tract should not be subjected to ureterosigmoidostomy.

The Lich-Gregoir antireflux plasty: experiences with 371 children

The Lich-Gregoir antireflux procedure is a simple and safe method for the treatment of primary reflux of all grades if the ureter is not grossly dilated on the excretory urogram. Reflux was cured in 97.7 per cent of 429 ureters in 371 children. A stenosis of the terminal ureter requiring reimplantation occurred in 0.5 per cent. The over-all rate of reinterventions was 3.7 per cent. This low complication rate makes surgical correction of reflux advisable if urinary tract infection and primary reflux cannot be eradicated by continuous antimicrobial therapy within 6 months.

[Parenteral feeding after ureterosigmoidostomy: nitron balance, free plasma amino acids and state of proteins]

The postoperative protein metabolism of 11 patients who had required either a colon conduit or ureterosigmoidostomy urinary diversion was examined. From the 3rd to 10th postoperative day day, each patient received a standard parenteral alimentation (100 g amino acids and 2000 kcal/24 h). Nitrogen balance, plasma level of the free amino acids, and the C3c-, C4-complement and transferrin fraction in plasma were determined regularly. The results showed that this substitution therapy succeeded in avoiding serious alterations in the parameters measured.

Transcatheter embolization of the kidney with butyl-2-cyanoacrylate: experimental and clinical results

The technique and efficacy of therapeutic catheter embolization of the kidney with butyl-2-cyanoacrylate (Histoacryl) were studied in 80 rabbits (including control groups) and in 10 dogs. A mixture of butyl-2-cyanoacrylate, 50% glucose, and tantalum powder was used for the embolization. Complete and permanent vascular occlusion was found in nearly all cases. The main complication observed was a reflux of embolizing material into the lumbar arteries, which occurred in seven rabbits. Clinically therapeutic embolization was performed in six patients with hypernephroma. The indication for embolization in these patients, as well as in two others with iatrogenic lesions, was pronounced hematuria. Cessation of bleeding was achieved in all cases. For embolization the coaxial catheter technique is recommended; in special cases with extensive arteriovenous shunts, adjunctive balloon occlusion would be advisable.

Simultaneous balloon occlusion of the renal artery and hypothermic perfusion in in situ surgery of the kidney

Renal ischemia and cooling may be achieved by intraluminal balloon occlusion and intermittent hypothermic perfusion using a double lumen, balloon-tipped catheter introduced into the renal artery percutaneously. This technique was used successfully in 26 of 31 extensive nephrolithotomies, eliminating the need for dissection and clamping of the renal artery and intricate surface cooling. Intrarenal operations could be performed as effectively as with clamp occlusion. Despite a mean ischemia time of 54 minutes the individual 131I-hippuran clearance of the operated kidneys was only reduced to a mean 78.4 per cent of the preoperative value 2 to 3 weeks postoperatively and increased to 92.2 per cent after 3 to 6 months, with a tendency toward further improvement.

[Extrarenal manifestations of renal cell carcinoma: the primary metastatic lesion (author's transl)]

In 18 patients, histologic evaluation of a solitary distant metastasis with characteristic hypernephroid pattern subsequently led to the diagnosis of renal cell carcinoma. The metastatic lesion was treated surgically in 15 cases; 14 patients underwent radical surgery and one patient with a solitary kidney underwent partial nephrectomy. Osseous metastases were predominant (12 out of 18). There was an excellent morphologic agreement between metastatic and primary lesions: in no case were metastases less differentiated than the primary tumor. Therefore in all cases of metastases with hypernephroid structures an aggressive search for renal malignancy is required. Five-year survival was 5% and identical to a group of 61 patients with metastases and a symptomatic renal cell carcinoma at diagnosis. The poor prognosis was not influenced by surgical extirpation of the solitary metastasis.

The impact of in-situ balloon occlusion of the renal artery and hypothermic perfusion on renal blood flow

Unilateral renal blood flow was evaluated in-situ in 13 dogs by cineangiodensitometry and microsphere distribution studies before and after intermittent balloon occlusion with and without hypothermic perfusion of one kidney. The contralateral kidney served as control. No significant difference in renal blood flow and vascular resistance was noted before, and 5, 30 and 60 minutes after unilateral intra-arterial manipulation. Compartmental flow distribution studies in 5 dogs revealed no evidence of alteration of intra-renal haemodynamics. In a clinical pilot study, unilateral renal blood flow measured by cineangiodensitometry showed no change of clinical significance 5 and 60 minutes after intraluminal balloon occlusion of the renal artery for 60 seconds.

[Intraluminal balloon occlusion of the renal artery: clinical applications and observations (author's transl)]

A method permitting percutaneous catheterization and temporary balloon occlusion of the human renal artery with a 5-F-Swan-Ganz-Catheter is presented. When properly performed, the arterial occlusion is reliable, low in complications, and less traumatizing to the vessel than external clamp occlusion. The technique was employed in 112 patients for occlusion of the renal artery prior to tumor nephrectomy, for attaining stop-flow conditions for improved nephrophlebography, for preventing the reflux of emboli at transarterial embolisation of inoperable kidney tumors, or, combined with simultaneous hypothermic perfusion via the second lumen of the catheter, in extensive kidney surgery necessitating ischemia. Particularly this last range of application offers new possibilities for in-situ surgery of the kidney, as it renders dissection of the renal pedicle and cumbersome surface cooling of the kidney unnecessary.

[Renal blood flow measurements by cine-angiodensitometry (author's transl)]

Angiodensitometry complements conventional renal angiography and provides important additional functional information without subjecting the patient to any further stress. Since blood flow through the renal arteries can be determined, it is an important method for the preoperative investigation of renal disease.

A simple method for in situ preservation of the ischemic kidney during renal surgery

A simple method combining the advantages of intraluminal occlusion of the renal artery with hypothermic perfusion of the ischemic organ is presented. Using a double-lumen, balloon-tipped catheter, which is introduced from the periphery, the kidney can be rendered ischemic and can be perfused simultaneously. Initial, hypothermic perfusion and subsequent arrangement on the surface of the open wound effectively protected canine kidneys against ischemic injury over 2 hr of ischemia.

[Occlusion of the renal artery by intra-arterial injection of thrombin in a case of inoperable renal tumour (author's transl)]

In a 53-year-old man with an inoperable metastasizing renal carcinoma embolic occlusion of the renal circulation was achieved by injection of thrombin (600 NIH units) through a balloon catheter into the renal artery. With short-term administration of analgesics and under anti-biotic cover the post-embolic course ran without complications. The general condition of the patient is good and macrohaematuria had, at the time of the report, not recurred for two months.

[Retrograde renal phlebography with balloon occlusion of the renal artery. Technique and scope of a new method (author's transl)]

A new method of retrograde phlebography of the kidney is described; it is carried out by using a balloon catheter in the renal artery for occluding the circulation. The procedure has been carried out in 13 patients without complication. Early experience has provided very good results in the diagnosis of malignant renal tumours; invasion into the venous system can be demonstrated radiologically. In particular, in cases of carcinoma of the renal pelvis, this method represents a significant improvement of the hitherto unsatisfactory angiographic techniques.

Ballon occlusion of the renal artery in tumor nephrectomy

A method of preoperative intraluminal occlusion of the renal artery in cases of kidney tumors using a 5F Swan-Ganz ballon catheter is presented. The procedure was used in 26 tumor nephrectomies without complications and resulted in marked facilitation of the operation in 70 per cent of the cases.

[Short time in-situ preservation of the ischemic kidney by a simple initial hypothermic perfusion with various cold solutions. An animal experimental study]

In unilateral nephrectomized beagle dogs the remaining kidney was subjected to 2 hrs of ischemia in situ. The ischemic organ was cooled to 22--23 degrees C by initial hypothermic perfusion over a 5-F catheter introduced into the renal artery via the carotid artery. It was then left in the open abdominal wound without any further attempts of cooling. Three perfusates were used: an isoosmolar Dextran solution (Eisenberger), a hyperosmolar, "intracellular" electrolyte solution (Sacks), and a hyperosmolar, "extracellular" electrolyte solution. There was a mean postoperative increase in serum creatinine levels of 0.6 mg-%. By the 3rd p.o. day at latest the serum creatinine was again within normal limits. The inulin and PAH clearances on the 7th and 14th p.o. day showed no significant differences to preoperative determinations. No definite advantage or disadvantage was noted among the three perfusates. All control dogs whose kidneys were made ischemic for 2 hrs without perfusion died due to acute tubular necrosis. Apparently the homogenous cooling and flushing by the initial perfusion is of more importance for good preservation in this situation than the composition of the perfusate.