Exam 4 - Nephrectomy Flashcards
what is a nephrectomy?
removal of the kidney only!!!!
ureter is ligated close to the kidney!
what is a uteronephrectomy/nephroureterectomy?
removal of the kidney & majority of the ureter!!!
ureter ligated close to the bladder
what is a partial nephrectomy?
removal of part of the kidney - uncommonly performed in vet med
before looking into removing a kidney, what 2 questions must you think about?
- risk of leaving the kidney in the body should be greater than the risk of removing it
- remaining kidney must be able to maintain homeostasis now & in the future
what are the 4 general categories of indications for removing a kidney?
- irreparable trauma - herniation of a kidney through the body wall or traumatic bisection of a kidney
- neoplasia - solid renal tumors (carcinomas, sarcomas, nephroblastomas) - full staging is important here!!! kidneys can be a site of metastasis from another primary tumor
- severe hydronephrosis??? need to look at the underlying cause here before proceeding
- infection - rarely necessitates nephrectomy but in select cases, can be considered
what are some examples of when it would be appropriate to consider the need for a nephrectomy due to infection?
severe severe hydronephrosis
persistent, non-responsive to medical management infection
unilateral infection
why do you need to pause before pursuing a nephrectomy due to hydronephrosis?
hydronephrosis usually occurs secondary to ureteral obstruction & there are many ways to treat this without sacrificing the kidney such as ureteral stents, ureterotomy, subcutaneous ureteral bypass, & neoureterocystostomy
what do you need to consider in a patient with hydronephrosis before pursuing a nephrectomy?
is the patient azotemic? are there functional nephrons remaining? underlying cause?
if stones - can happen in other kidney too, many other options
if stricture - could happen in other kidney, many other options
ectopic ureter - can reroute!
cancer - probably need a ureteronephrectomy for margins!
why is full staging of renal neoplasia important prior to doing a nephrectomy?
many renal tumors are malignant!!! 16% metastasis at diagnosis & 77% at death
kidneys may be a site of metastasis for another primary tumor
what is the minimum pre-op planning needed prior to a nephrectomy?
complete bloodwork & urinalysis - need to know if you have renal azotemia, because these patients are much less likely to tolerate a nephrectomy especially if the kidney removed still has function!!!
can’t blame renal azotemia on 1 kidney!
abdominal imaging - ultrasound or ct, need to evaluate status of both kidneys/ureters/bladder (neoplasia can significantly change your surgical plan)
blood typing - if they have a large mass
how would you get a single kidney gfr? why would you do this?
possible to obtain with nuclear scintigraphy
may help predict how well a patient may tolerate a nephrectomy but has limited availability, will cause a delay in surgery (because it is radioactive), & has questionable accuracy in the face of ureteral obstruction
how is a nephrectomy performed?
- long ventral midline incision & balfour retractors used to open patient - free kidney from retroperitoneum (may have to ligate some vessels) & retract it ventromedially
- identify the vasculature - ligate the artery first!!! watch for branches!! use one circumferential & 1 transfixed stay with the patient & 1 circumferential stays with the kidney - ligate vein second (except if patient is intact because the left renal vein receives blood from gonadal vein!!!) do not ligate artery & vein together
- follow the ureter FROM the kidney TO the bladder - circumcaval ureters are not uncommon!! ligate the ureter at the level of the urinary bladder with 2 circumferential sutures staying with the patient & leave the smallest ureteral remnant possible!!!
when would you not ligate the renal vein in a patient during a nephrectomy?
if the patient is intact - renal vein receives blood from the gonadal vein
when may a laparoscopic ureteronephrectomy be done for a patient?
select cases - very large tumors especially with caval invasion are a different beast and are so scary!!!! probably don’t!!!
what are the immediate post-op considerations for a patient following a nephrectomy?
maintain gfr in the remaining kidney!!! iv fluids, blood pressure monitoring, & avoid nephrotoxic drugs (no NSAIDS!!!! - use opioids, gabapentin, etc for pain control)
monitor kidney values as you taper & discontinue fluids at suture removal & then as needed
monitor PCV in immediate post-op period
this 10 y/o FS mini schnauzer had a nephrectomy 2 years ago for ureteral obstruction - her right ureter is partially obstructed now & she has mild elevations in her kidney values. what do you do now?
ureterotomy to remove ureteral stone & place ureteral stent!
