Pancreas Transplant

What are the indications for pancreas Tx

        Patients with type I diabetes and ESRF may present prior to dialysis, whilst on dialysis or after KTx.

o   With functioning Kidney transplant – patient may undergo pancreas after kidney (PAK)

o   Without functioning KTx :

§  Simultaneous pancreas kidney Tx (SPK): this is the most common option exceeding all other options combined. Ouctomes are superior to solitary pancreas Tx.

§  Pancreas after kidney Tx (PAK): KTx is from either a deceased or living (to reduce waiting time) donor. Most of benefit derives from Ktx. Ouctomes are inferior to SPK.

§  Simultaneous living donor kidney and deceased donor pancreas (SPLK)

§  Living donor kidney-pancreas Tx: the living donor provides the tail of pancreas. Results are comparable to SPK. Donor morbidity is significant

o   Most of benefit derives from kidney Tx. So patients are advised to adopt which ever option produces quickest KTx when the wait for SPK is long.

        Non-uremic type I diabetic patients may be considered for pancreas transplant alone (PTA). These are labile diabetics who have severe complications from diabetes most commonly brittle disease with severe hypoglycaemia. Whether it results in mortality benefit is unknown – the patient assumes the risks of immunosuppression, which in contrast to the uraemic patient is already assumed by virtue of KTx.

        In both contexts pancreas transplantation PTx is an alternative to intensive insulin therapy which has risks of severe recurrent hypoglycaemia which may lead to neurological injury, especially when combined with hypoglycaemic unawareness.

What is the impact of donor quality on outcome

        Age, hypotension, vasopressor use and hyperglycaemia are all of greater concern in potential deceased donors.

        Visual inspection is most important – the pancreas should be soft and free of fibrosis

How can pancreas transplants be implanted

        Portal drainage or systemic drainage of venous outflow – portal drainage reduces systemic hyperinsulinaeia. This has not been shown to improve outcome

        Bladder or enteric drainage of exocrine secretion – the major advantage of bladder drainage is ability to monitor unrinary amylase for assessing graft function. This is more important in solitary pancreas Tx as in PKTx the kidney function is a sensitive proxy for pancreas rejection. Bladder drainage is associated with recurrent UTI, haemorrhagic cystitis, bicarbonate wasting and dehydration. Thus enteric drainage is preferred.

        Enteric drainage is combined with portal venous drainage because of the orientation of pancreas.

What are the unique complications of pancreas Tx

Immediate

        Bleeding – common

Early

        Graft thrombosis – much more common than other transplants. Most common cause of early graft loss. Anti-coagulation and improved immunosuppressions have improved the thrombosis rate.

        Duodenal leak10% usually 1-2 weeks after Tx. Treated by re-operation. Can be treated by attempting to repair the leak (usually from closed end of duodenum), change to bladder drainage and decompression of duodenum using a foley catheter or removing the Tx. Drainage, either open or CT-guided may be used.

What is the outcome

        SPK: mortality benefit compared with dialysis or KTx alone

o   Reduces recurrence of diabetic nephropathy

o   Diabetic neuropathy is slowed and even reversed in some cases

o   Most patients enjoy improved quality of life.

        There is no clear evidence that PTA contributes to reduced mortality

 

Description: Pancreas6

Arterial anastomosis: SMA to external iliac Art

Venous Anastomosis: Portal vein to external iliac vein

Enteric Anastomosis: Duodeno-enteric side to side