Editing Pancreaticoduodenectomy


== Resection of: ==

* Distal stomach
* Duodenal loop and DJ flexure
* Distal CBD
* Head and uncinate process of pancreas


== History ==

* First described 1909 (Kausch)
* First successful resection 1935 (Whipple)
* First performed in one stage 1941 (Trimble)

== Pre-op: ==

* No absolute upper age limit, but need to be very careful >75yo

== Controversies ==

* Pylorus-preserving (conservative) vs non-pylorus-preserving (conventional)
** No RCTs have suggested superiority of pylorus-preserving approach
* Pancreaticojejunostomy vs pancreatogastrostomy
** Some studies have reported fewer fistulas and leaks with pancreatogastrostomy, but this was not reproduced in RCTs
* Somatostatin analogues to reduce pancreatic fistula
** Mixed results when used perioperatively
* Extent of lymphadenectomy
** No evidence to suggest improved survival after extended lymphadenectomy
* Laparoscopy/robotics
** Similar outcomes for certain high-volume, experienced surgeons, but not widely adopted due to being very hard
** Open Whipple remains standard of care
* Antecolic vs retrocolic duodenojejunostomy
** Antecolic may improve gastric emptying


== Technique ==

* Bilateral subcostal is best, but midline can also be used
* Exploration for metastatic disease - abort if found
* '''Trial dissection:'''
** Enter lesser sac by taking omentum off transverse colon
** Kocher manoeuvre to level of left lateral aortic border, which confirms that the tumour is resectable
** Identify infra-pancreatic SMV by following middle colic vein down. Make a tunnel behind pancreas, anterior to portal vein, to confirm it can be freed from PV.
** Divide lesser omentum
** Now make a tunnel in front of PV from above, joined to inferior tunnel behind neck of pancreas

* '''Conservative pancreaticoduodenectomy'''
** Right gastric artery and GDA ligated and divided, after confirming collateral circulation through CHA
** First part of duodenum separated from pancreas - mobilise the pylorus and proximal 6cm of duodenum
** Divide CBD
** Divide proximal duodenum (3cm distal to pylorus)
** Mobilise ligament of Treitz to allow jejunum to come up into the supracolic compartment
** Divide distal duodenum
** Divide pancreatic neck under vision 
*** Stapler
*** Protect PV posteriorly
** Separate head and uncinate process of pancreas from PV and SMV (moving from left to right, peeling the disconnected pancreatic head off the vessels)
* '''Reconstruction''' (16.14A above)
** Pancreatic neck to jejunum (double layer duct to mucosa)
** Bile duct to jejunum (single layer end to side)
** Duodenal stump to jejunum (two layer end to side, 25cm distal to biliary anastomosis)
* Drains adjacent to joins
* Feeding jejunostomy in patients with pre-operative malnutrition

== Post-op care: ==

* BGL management - needs insulin infusion
** Should switch to subcut insulin on day 1 post-op
* NGT placed intra-operatively
** Likely removed day 1
* Incentive spirometry
* Some surgeons would advocate for prokinetics from early on
* Drains usually left in place until day 4 or 5, with a drain tube lipase/amylase prior to removal

== Complications ==

* Perioperative mortality
** <2% at high-volume centres
* Overall morbidity 30-50%
* Haemorrhage
** Early bleeding usually results from a failure to achieve adequate haemostasis that is best managed by return to OT
** Late bleeding is usually the result of an inflammatory process that causes vascular erosion and formation of arterial pseudoaneurysm formation
*** Most commonly GDA stump, followed by hepatic artery, SMA and splenic artery.
*** Treated effectively endovascularly - either transcatheter arterial embolization (85% successful) or stent-graft placement or both
**
* Delayed gastric emptying - 15%
** Functional gastroparesis
** Controversial whether pylorus-preserving operations affect this
** Typically presents with inability to tolerate solid foods or prolonged NGT requirement
** Need to exclude mechanical obstruction due to leak/abscess/stricture - CT +/- gastroscopy +/- contrast swallow
**
** Management
*** Discontinuation PO intake
*** Resumed NGT decompression
*** Jejunal feeds
*** Prokinetics
*** Nutritional support
*** CT to exclude intra-abdominal complication including abscess
* Wound infection - 7%
* Pancreatic fistula - 12%
** Risks:
*** Soft, fatty glands
** Presentation
*** Transient anastomotic leak
*** Intra-abdominal abscess
*** Frank fistula formation
** Defined as drain tube lipase/amylase > 3 times ULN on day 3 or later, regardless of output volume. Divide into grades A B and C based on severity to guide management.
** Grade A: little to no clinical impact, no specific intervention. Sometimes elect to remove drain incrementally over successive days to prevent fistula formation. Normal diet, don't delay discharge. 
** Grade B or C: drain intra-abdominal collections, restrict PO intake, nutritional support, Long-active somatostan analogues may reduce output - debated. Empiric antibiotics if concern for infection. 90% of fistulae close spontaneously, generally within 4 weeks. 
*** Indications for re-exploration: severe clinical instability, sepsis, organ dysfunction. Can need repair or revision of PJ anastomosis.
**
* Bile leak - 2%
* Pneumonia - 1%
* Pancreatitis - 1%
* Cardiac events - 3%
* Intra-abdominal abscess - 6%
* Pancreatic insufficiency
** Unpredictable, but rare for those with a normal gland

[[Category:HPB]]