renal autotransplantation is a method of removing kidney from its place of origin , repairing it and transplanting it in another location of the body ( most commonly , the iliac fossa ) of the same patient .
this procedure was first performed by hardy in 1963 . since hardy 's landmark surgery for management of a high ureteral injury ,
renal autotransplantation has been described in the treatment of renal arterial disease , renal cell carcinoma , nephrolithiasis etc .
it has been demonstrated that tumour size ( > 4 cm ) identified on computerised tomography ( ct ) scan , is the most reliable predictor of rupture .
here we describe the anaesthetic challenges in a bilateral ex - vivo nephron sparing surgery with autotransplantation for giant angiomyolipoma .
a 28-year - old unmarried female weighing 55 kg presented with lower abdominal discomfort and vague lump in the abdomen of 5 years duration .
blood investigations were normal and contrast enhanced abdominal ct with angiogram showed bilateral highly vascular huge renal masses suggestive of angiomyolipoma [ figure 1 ] .
she was taken up for right radical nephrectomy , bench surgery and autotransplantation after adequate pre - operative preparation .
pre - operative computed tomography angiogram - highly vascular angiomyolipoma we instituted general anaesthesia supplemented with low thoracic epidural at t11 - 12 interspace and epidural analgesia was maintained with 0.2% ropivacaine and fentanyl 2 mcg / ml at the rate of 4 - 6 ml / h .
anaesthesia was induced with glycopyrrolate 0.2 mg , midazolam 1 mg , ramosetron 0.3 mg , fentanyl 100 mcg and propofol 100 mg .
intubation was facilitated with 100 mg succinylcholine and anaesthesia was maintained with n2o , o2 , isoflurane and atracurium .
electrocardiogram , pulse oximetry , invasive blood pressure , end - tidal carbon dioxide , central venous pressure ( cvp ) , core temperature and hourly urine output were monitored .
abdomen was entered through a right thoracoabdominal incision [ figure 2 ] , excising the tenth rib and splitting the diaphragm .
right kidney with the mass ( 30 cm  15 cm ) was removed and cannulated for cooling with the histidine tryptophan ketoglutarate solution .
the warm ischemia time was 1 min and 45 s. bench dissection was carried out and kidney was autotransplanted .
cold ischemia time was 4 h. during this period , the anaesthetic goal was to maintain mild hypertension .
patient had massive blood loss approximately 5 l , which was corrected with five units of packed cells , four units of fresh frozen plasma , 9 l of crystalloids and 1 l of colloid .
she had continuous oozing from the wound site suggestive of coagulopathy due to massive blood loss and transfusion which was corrected with further transfusion of blood components ( two units of packed cells , three units of fresh frozen plasma , four units of platelets and four units of cryoprecipitate ) .
she was haemodynamically stable and coagulopathy was corrected by the second post - operative day and she was weaned off inotropic and ventilatory support .
after 4 weeks , she was posted for the left nephrectomy with bench surgery and autotransplantation as she had a large tumour ( 26 cm  18 cm ) in the left kidney with high risk of bleeding .
renal doppler showed suboptimal function of right transplanted kidney . only a single arcuate artery in the lower pole cortex picked up doppler flow with increased resistance index .
the surgical technique and induction of anaesthesia were similar to what was used for the right nephrectomy .
patient was adequately hydrated before nephrectomy with 3 l of crystalloids to maintain adequate urine output .
warm ischemia time was 2 min 13 s. cold ischaemia time was 2 h 48 min .
after the nephrectomy , fluids were restricted with a goal to maintain cvp of 6 - 7 cm of water . before
the release of the cross clamp after transplantation , cvp was increased to 16 - 18 cm of h2o .
the target blood pressures were systolic more than 140 mm hg , mean arterial pressures more than 95 mm hg and the diastolic pressure more than 85 mm hg as was practiced in renal allotransplantation .
frusemide 200 mg and sodium bicarbonate 25 ml were administered and urine output was adequate after reperfusion .
blood loss was around 1.5 - 2 l. she was infused nine litres of crystalloids , 500 ml colloid and two units of packed cells .
the urine output was 3.6 l. at the time of discharge her creatinine was 1.4 mg / dl and it was 1.5 mg / dl on day 30 .
the follow - up angiogram after 1 month showed a well - perfused kidney on the left side .
ex - vivo excision of the tumour and autotransplantation is a feasible option for bilateral giant renal lesions in select cases , thus avoiding the morbidity associated with bilateral nephrectomy and renal replacement therapy .
it is a technically demanding procedure and is contraindicated in severe occlusive atherosclerosis of the iliac arteries .
renal autotransplant is a two - step procedure ; first the kidney is removed , dissected extracorporeally and then transplanted . surgical approach in removing the kidney is similar to that of living donor nephrectomy .
the problems that we had during the right nephrectomy were massive blood loss due to the highly vascular large tumour and maintenance of adequate renal perfusion .
once the autotransplantation was completed it was important to maintain adequate intravascular volume with colloids or blood to ensure well - perfused kidney .
cvp was maintained at 16 - 18 cm of water and the mean arterial , systolic and diastolic pressures were maintained above 95 mm hg , 140 mm hg and 85 mm hg respectively , with risk of increased blood loss .
we had to start the patient on dopamine and dobutamine to maintain the blood pressures .
intravenous mannitol minimises ischemic injury to the kidney and hasten the restoration of renal function .
for the second autotransplant the problems we anticipated were a large angiomyolipoma which could bleed profusely making maintenance of cvp and blood pressures difficult . also , the operated kidney had suboptimal function complicating fluid management .
after discussion with the surgeon , we decided to manage the patient as a donor before the nephrectomy and administered fluids as for a donor for allotransplant .
after the nephrectomy , as the patient was anepheric we decided to treat the patient as an allotransplant recipient .
a targeted approach , with restriction of fluids and replacement of blood loss was practiced to maintain the cvp at 6 - 7 cm h2o during bench dissection . during the final stages of bench dissection ,
cvp was raised to 16 - 18 cm of h2o , thus enabling the patient to be adequately filled up during reperfusion with achievement of the target mean arterial , systolic and diastolic pressures .
flower vase thoracoabdominal incision was used [ figure 2 ] and analgesia was maintained with a low thoracic epidural , intravenous fentanyl , tramadol and paracetamol .
renal bilateral ex - vivo nephron sparing surgery with autotransplantation is a highly invasive surgery , which demands proper intraoperative fluid management and maintenance of adequate urine output .
invasive monitoring is preferred to achieve this goal and enable smooth patient recovery and preservation of renal function .
 extracorporeal  work bench surgery with subsequent autotransplantation is a challenge from both anaesthetic and surgical point of view when performed bilaterally or in a solitary kidney . 
 a 28-year - old female with bilateral giant angiomyolipoma of kidneys was taken up for renal autotransplantation . 
 patient had a huge tumour , which was the largest reported exophytic tumour to be excised by this technique . 
 both kidneys were operated at an interval of 1 month , under combined general and epidural anaesthesia . 
 anaesthetic challenges faced during the procedure were maintenance of adequate perfusion of the grafted kidneys , containment of massive blood loss and coagulopathy during the perioperative period . 
 patient recovered in due course with functioning autotransplanted kidney . 
 a careful pre - operative preparation with intraoperative maintenance of adequate blood volume and blood pressure is the key for graft survival . 
INTRODUCTION
CASE REPORT
DISCUSSION
CONCLUSION