Bombay Hospital Journal EDITOR'S CHOICEContentsHomeArchivesSearchBooksFeedback

Category Title

SURGICAL COMPLICATIONS FOLLOWING RENAL TRANSPLANTATION

Sadanand W Thatte

 

Improved surgical techniques and immunosuppressive agents have reduced t h e incidence of postoperative complications
following renal transplant. Nevertheless vascular and urological complications still occur and account for significant morbidity and graft failure.

VASCULAR COMPLICATIONS
Haemorrhage : Bleeding in the postoperative period can be a major emergency. Bleeding can be due to
a) Inadequate preparation of graft bed
b) Unrecognised injury to the kidney during donor nephrectomy
c) Abnormal coagulation due to inherent platelet dysfunction.
d) Faulty vascular anastomosis
e) An hyperacute rejection episode or venous thrombosis may cause rupture of the renal capsule.

Graft Thrombosis :
Thrombosis of the graft renal artery or vein is heralded by the sudden onset of oliguria, swelling of the graft and proteinuria. Vascular thrombosis is clinically difficult to distinguish from acute tubular necrosis. DTPA isotope scan or Duplex ultrasonography help differentiate between the two. The precise cause of thrombosis remains obscure in
a vast majority of cases. Arterial thrombosis occurs within the first 24 - 48 hrs of transplant whereas peak incidence of venous thrombosis is 3 to 9 days. Thrombosis may be secondary to hyperacute rejection, postoperative hypovolaemia due to over diuresis, faulty technique of anastomosis, injury to intima of vessel during harvesting or during erfusion or atherosclerosis of recipient vessels.

There is no effective treatment for vascular thrombosis. There are case reports of salvaging the kidney when thrombectomy or evacuation of haematoma was performed within one hour. Transplant nephrectomy may be required to prevent graft rupture and exsanguinating haemorrhage.

Renal Artery Stenosis : It can occur as early as 2 days post transplant but usually occurs between 3 and 24 months. The patient presents with worsening hypertension after a stable post transplant course and the creatinine may rise. The stenosis may be due to faulty sutures, damage to intima, and improper opposition with rotation or angulations due to
excessive length of the vessels. Duplex scanning MR angio and captopril radionuclide scan help in diagnosing. DSA remains the gold standard.

The repair is either resection and revision of anastomosis, patch angioplasty or bypass graft. Percutaneous Transluminal Angioplasty (PTA) is safe and effective with high rate of success in treating renal artery stenosis in well-selected cases.
Use of stents has shown good short-term results.

Mycotic Aneurysm : This is a rare complication due to deep wound infection with secondary involvement of vascular sutures.

 

UROLOGICAL COMPLICATIONS
Urine Leak :
Urine leak presents early in the post operative period. The patient presents with decreased urine output, rise in serum creatinine and may have copious fluid drainage from the drain site or the wound. The leak may occur due to vascular insufficiency due to inadequate preservation of ureteral blood supply during donor nephrectomy, ureter may be
involved in renal rejection, undue tension createdby short ureter or uretral blow out due to out .ow obstruction. The urine leak is diagnosed by ultrasound, drain fluid biochemistry and cystogram. Management depends on site and degree of
disruption. Bladder leak usually responds to 2-3 weeks of Foley drainage. If .stula is substantial in size then exploration and layered closure is required.

Ureteral Obstruction : Ureteral obstruction may be asymtomatic because of lack of innervations of the transplanted kidney and may occur early or late. In the post transplant period. Obstruction early in the course may be due to oedema at the site of anastomosis, ureteral torsion or blood clot obstructing the out.ow. Obstruction later in the course is due to ureteral stricture or .brosis. Hydronephrosis is evident on ultrasound and an IVP demonstrates the site of obstruction.
Balloon dilatation in early obstruction has a 50% to 70% success rate. Percutaneous nephrostomy may be used for dilatation and placement of a stent. If percutaneous method fails, surgical approach is necessary. A new ureteroneocystostomy may be needed. If the obstruction is proximal an ureteroureterostomy to native ureter can be done. A Boari .ap may be constructed if the transplant ureter is too short and no native ureter is available.

LYMPHOCOELE
Lymphocoele is a collection between inferior pole of the graft and bladder. This is due to inadequate ligation of afferent lymphatics coursing the recipient iliac vessels or within the allograft hilum or decapsulation of the kidney transplant. This
usually shows up between 3 weeks and 3 months after transplant surgery. It may cause compression of ureter with a rise in creatinine or compression of the vein and causing oedema of the leg. This is diagnosed by ultrasound. The aspirated fluid has a creatinine concentration similar to that of serum and elevated proteins.

Management strategy depends on the size and symptoms. USG guided aspiration and insertion of 8-12F drainage tube, sclerotherapy with10% povidone iodine solution may be useful if it is not loculated. Intraperitoneal marsupalisation drains
the .uid into the peritoneum. Laparoscopy has been used for creating intraperitoneal window.

WOUND INFECTION
Wound infection usually occurs around postoperative day 7 and more frequently in obese patients. Therapy with systemic antibiotics should be initiated immediately. Early desloughing may be needed. Staphylococcus aureus is the most common organism.

Most problems are neither life threatening nor hazardous to the outcome of the graft. Meticulous
 

To Section TOC
Sponsor-Dr.Reddy's Lab