Postoperative management of a kidney transplant recipient

The postoperative management of a kidney transplant recipient requires meticulous monitoring of urine output and electrolyte levels.

Renal allografts will not necessarily make urine as soon as they are reperfused. Depending on the particular center, the incidence of delayed graft function ranges from 5% to 15% in cadaveric and from 0% to 5% in live donor kidney transplantation.

The astute clinician will query the patient as to how much urine was produced pretrans-plant so as not to be lulled into a false assurance that the graft is functioning because ‘there is urine’.

Although no physician can predict the postoperative urine output of a kidney transplant recipient with 100% certainty, there are several factors that consistently contribute to delayed graft function.

Cadaveric donors, increased age of donors, ethnicity of donors, diabetic donors, prolonged warm and cold ischemia, and ischemia/reperfusion injury are all risk factors for delayed graft failure resulting from acute tubular necrosis.

It must be remembered that delayed graft function in kidney transplant recipient begins at the time of organ reperfusion and the urine output begins and remains low and does not change abruptly.

Acute changes in urine output in a functioning graft can be a signal that a catastrophic insult has occurred to the graft and must be reported to the transplant team immediately.

Several causes of acute decreases in urine output in kidney transplant recipient are surgical complications and are correctable if prompt attention is appropriated.

A list of technical causes of low urine output includes renal artery/vein thrombosis or kinking, ureteral obstruction, and compression of the graft by a fluid collection (hematoma, lymphocele, seroma, or urinary leak). Hypovolemia can also cause oliguria as in other postoperative patients.

Vascular, urologic and lymphatic complications require prompt diagnosis and treatment to salvage the graft. The workup of decreased urine output often depends on institution and transplant team, but usually consists of ultrasound, color flow Doppler, or radionuclide imaging of the graft.

An ultrasound is invaluable in this situation because it can be performed quickly on the kidney transplant recipient at the bedside and can evaluate for both vascular compromise and fluid collections. However, the call to the transplant team must not be delayed while waiting for ultrasound results.

Suggested Readings on Postoperative management of a kidney transplant recipient

Halloran PF, Hunsicker LG. Delayed graft function: state of the art, November 10, 11, 2000. Am J Transplant 2001;1:115

Humar A, Leone JP, Matas AJ. Kidney transplantation: a brief review. Front Biosci 1997;2:41.

Add Comment