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PANCREATITIS
23
Purse-string sutures are used in both walls of the stomach and the back wall
is approximated to the anterior wall of the pancreas at the site of entry of the
T-tube (fibrous glands hold sutures very well). Ensuring that sufficient length
of T-tube remains in the stomach to allow expansion (10–12cm), the anterior
stomach wall and abdominal wall are approximated as for a percutaneous
endoscopic gastrostomy (PEG) feeding tube and the T-tube is brought out
through the abdominal wall. The T-tube is removed after 6 weeks.
Strictures and focal disease
Strictures and focal disease offer at least a theoretical chance of improving
symptoms with a limited approach. If focal disease is distal to a stricture then
resection of the affected segment seems logical and is associated with a rela-
tively low morbidity and mortality, especially if the spleen is preserved. If
conservative measures fail, in the presence of a stricture we would offer the
patient a distal pancreatectomy. It has to be noted however, and explained to
the patient that pain relief may not be complete and that pain may recur within
a few years. A large percentage of patients in this category will get further
(eventually severe) pain from the pancreatic remnant and represent a propor-
tion of those referred for further surgery. Consequently we would offer islet
cell transplantation to these patients to minimize the problems that would be
encountered if additional surgery was required with further reduction of the
islet cell mass.
Fig. 1.16 A T-tube is inserted into the pancreatic duct.
PANCREAS
24
In patients with a stricture in the mid-pancreatic duct at ERCP or MRCP, we
would always pursue an endoscopic approach initially, although stricture dila-
tation is of little value. Pancreatic ductal stenting, however, is almost always
possible with strictures and, as for large duct disease, an improvement in
symptoms implies that distal pancreatectomy is worth considering. Endoscopic
stenting of the pancreas cannot be pursued in the long term due to the risk of
further damage caused by the procedures or stents left in for too long.
Expanded head
This relatively uncommon presentation in Australia and the United Kingdom
is widely seen in central Europe and some parts of the USA, and has resulted in
a variety of approaches (with recent modification by Japanese surgeons) that
are practised today (Frey and Amikura, 1994 ; Beger et al ., 1999 ; Gloor et al .,
2001 ; Ho and Frey, 2001 ). However, no series has been able to achieve aboli-
tion of pain and generally they report ‘reduction to an acceptable level’. These
procedures should certainly not be performed in centres that do not see a large
number of these patients.
Small duct disease
This is the predominant category in the United Kingdom and Australia, and
because of the relatively normal appearance of the gland, diagnosis is often
delayed. This delay produces secondary problems with patients losing confi-
dence in the system, opiate dependence, and established patterns of activity.
Finally, referral to a secondary or tertiary centres usually only occurs when all
potential diagnoses have been entertained and all therapeutic approaches have
already been tried. A segmental resection seems illogical in these patients and
attempts to implicate the head of the gland as the pacemaker in the disease fails
to accept the high levels of residual pain and early recurrence of problems in
those who have had conservative surgical procedures. Surgery must therefore
always be an absolute last resort in these patients, but when there are no
remaining options we favour total pancreatectomy and islet cell transplanta-
tion (as discussed in ‘Total pancreatectomy and islet cell transplantation’).
End-stage disease with or without previous surgery
In these patients, not only have all medical approaches been tried but they may
have had a variety of surgical procedures (segmental resections, drainage pro-
cedures usually over many years). A number of patients have also had pseudo-
cysts or inflammatory masses in the past, which should be considered when
surgery is being contemplated. No further local surgery is appropriate unless it
is believed that a previously effective approach is no longer effective due to a fail-
ure of the surgery (drainage procedures no longer draining due to stenosis etc.).
PANCREATITIS
25
In addition, pancreatic surgery should never be considered solely to treat
mechanical problems such as biliary obstruction or delayed gastric emptying
which can be simply addressed by bypass procedures.
In these patients where the quality of life is severely affected, we would con-
sider (if preoperative investigations suggested that this was appropriate), a
completion or total pancreatectomy and islet cell transplantation. Patients are
not considered suitable even for an assessment unless they state that they have
in excess of half of the days of the month occupied by severe disabling pain.
These patients are admitted formally for their assessment, which consists of a
consultation with a senior gastroenterologist, diabetologist, pain specialist,
and clinical psychologist. They are fully informed about the procedure and the
likelihood of diabetes and give themselves a mock insulin injection. The whole
process is coordinated by a pancreatic nurse specialist who also during the
2-day admission performs an extended glucose tolerance test and correlates all
investigations including ERCP, CT, MRCP, and faecal elastase to ensure that
they are current. The patients are also introduced to other patients who have
had the procedure, one recently and one more than a year ago. They are then
allowed home and brought back to a Pancreas Clinic a month later where they
are seen with their family. In the meantime, the clinicians discuss the case and
confine themselves to answering the following questions:
♦
Is the diagnosis of pancreatitis established beyond all reasonable doubt?
♦
Are the symptoms severe enough to warrant a total pancreatectomy?
♦
Is the patient appropriate for an islet cell transplant?
Any of the clinicians in the assessment team can express a ‘veto’ if they feel
the patient is not appropriate. This has occurred in about 3% of patients. The
patient is then seen a month later after they have had time to reflect and discuss
the information with their family. The month’s delay is to ensure that they
have had the opportunity to discuss the operation with their family and also
experienced any potential fluctuations in the level of their pain, which may
affect their views (Clayton et al ., 2003 ).
Until the late 1990s, autotransplantation of islets was only offered if the glu-
cose tolerance test was normal, but we have relaxed this over the last few years
and believe that a background production of insulin even if a patient is not
insulin dependent is valuable, and results in better diabetic control and
improved HbA1C levels. This is based on data from series of diabetic patients
who always fare better in terms of long-term complications if some insulin
production is maintained. In addition, the idiosyncratic and unpredictable
nature of the islet cell preparation from the removed gland, due to a number
of factors which are difficult to control, such as fibrosis of the gland and batch
PANCREAS
26
variations with collaginase, means that preoperative predictions are not
particularly useful. Even after the preparation and implantation in the liver,
outcome is affected by many unknown variables and results in an unpredicta-
ble insulin (as indicated by C-peptide) production after the procedure.
Furthermore, at least 80% of islet cell mass probably needs to be lost before
patients have an abnormal glucose tolerance test and even more before they
become insulin dependent. Without preoperative glucose clamp studies, islet
cell mass can never be known and resection of a gland where only 10% of islets
have been lost would produce very different results from one with an 80% loss.
It is almost certain, however, that most patients have lost much of their islet
function as 50–60% of patients with chronic pancreatitis eventually require
insulin.
This is the rationale for the change in policy with patients with minimally
abnormal glucose tolerance tests. In a patient who has a sufficient islet cell
mass, we would end up with less successfully implanted islets and insulin pro-
duction if the preparation was poor compared with a patient who has a mar-
ginally insufficient islet cell mass but a good preparation. This is fully explained
to the patients and, if they still are keen to proceed, they are listed for the
operation (Webb et al ., 2008 ).
Total pancreatectomy and islet cell transplantation
This procedure can only be performed in specialist centres due to the combi-
nation of a difficult surgical procedure and the need to produce the islet cells
for infusion on site. Splenic preservation is usually possible, but although the
splenic artery can be sacrificed and arterial supply maintained from the short
gastric vessels, the splenic vein must always be preserved in this operation due
to the increased portal pressure that results from islet cell infusion. This
increased pressure (although transient, returning to normal by 96 hours),
in addition to splenic vein ligation would be very likely to result in splenic
rupture.
The operation is performed using a transverse incision. After examination
of the peritoneal cavity for additional pathology and the effects of previous
surgery or disease involving the pancreas, mobilization of the gland begins.
Landmarks are often difficult to identify and severe fibrosis can distort key
areas such as the junction between the superior mesenteric and portal vein
just above the lower border of the pancreas, the gastroduodenal artery, and
the coeliac axis and its branches, particularly the left gastric artery. In this
procedure it is difficult to recommend a sequence of steps that should be
followed rigidly. The head should be mobilized initially where possible
and the superior mesenteric vein (SMV), bile duct, hepatic artery and portal
PANCREATITIS
27
vein identified. The inferior border of the gland to the left of the portal vein is
then elevated and mobilized until the splenic vein is identified. The splenic
artery and vein are preserved as long as possible to ensure a vascularized gland
and consequently viable islets. In addition we prefer not to divide the gland
and remove it in two segments (to preserve perfusion as long as possible) and
this sometimes makes complete exposure of the portal vein difficult.
Mobilization continues after division of the bile duct and gastroduodenal
artery until the gland is only attached by the splenic vessels, to the left of the
portal vein. The right gastric artery is also preserved to facilitate a pylorus
preserving reconstruction. The splenic artery and vein are then dissected free
(ligating and oversewing all branches) and the gland is removed and taken to
the islet laboratory.
While the gland is being prepared by collaginase digestion and the separa-
tion of islets, anatomical continuity is restored with a single loop to the duode-
nal remnant and the bile duct ( Fig. 1.17 ). Haemostasis must be meticulous
because 5000U of intravenous heparin are given just prior to islet cell infusion
in an attempt to prevent platelets and thrombus interfering with implantation.
Islet preparation takes 2.5–3 hours and the reconstruction 1.5 hours which
Fig. 1.17 Method of reconstruction after total pancreatectomy. The right gastric artery
is preserved to allow a pylorus-preserving approach. The duodenal remnant is shown
anastomosed end-to-end to the neoduodenum (proximal jejunum) but it can also be
performed end to side if this produces less tension.
PANCREAS
28
allows for a surgical break and a final check on haemostasis prior to the islet
infusion. Standard biliary anastomosis is as discussed later for a biliary
bypass.
Depending on digest volumes, it is occasionally necessary to purify the prep-
aration but this results in a loss of 50–60% of islets and frequently it is more
appropriate to discard some of the digest. Discarding up to 50% of the digest
would still mean more islets being infused than following purification. The
islets are infused into the left portal vein. Originally this was always through a
cannulated mesenteric vein (middle colic generally) but more recently we have
used the umbilical vein (after dilating it in the ligamentum teres). The vein can
be brought out on the abdominal wall, allowing postoperative portal vein pres-
sure measurements to be made. The left side is used in case of serious compli-
cations (abscess formation, portal vein thrombosis) when in theory the
situation could be salvaged by resection of the affected part. The digest infu-
sion of about 200mL is given over 20–30 minutes and controlled not simply by
the volume of digest but also by measuring the portal pressure rise (which is
not allowed to increase by more than 12mm of water or exceed a maximum of
20mm of water) after correcting for the inevitable small rise in the central
venous pressure caused by the fluid infused (the islets are suspended in
2–300mL of fluid).
At the end of the infusion, haemostasis is again checked, the spleen carefully
examined, and the abdomen closed ( Fig. 1.17 ). The patients are maintained on
a strict sliding scale of insulin for 10 days to maintain their blood sugar at
4.5–5.5mmol, reducing the metabolic demand on the implanting islets (Webb
et al ., 2008 ).
Pancreatic trauma ( Fig. 1.18 )
Pancreatic trauma fortunately remains relatively rare either with blunt or pen-
etrating injuries. The only large series in the literature emanate from a small
number of well-known centres (Asensio et al ., 2003 ). Nevertheless, with high-
speed road traffic accidents and increasing civil violence of different types,
these injuries appear to be on the increase. They pose major clinical problems
as they are generally associated with other significant injuries in ill patients and
frequently produce complications (Asensio et al ., 2003 ; Lin BC et al ., 2004 ).
Management of these patients depends entirely upon the stage at which they
present and the relative priority that has to be assigned to different injuries in
polytrauma patients (head injuries particularly). They will vary from isolated
stab wounds seen almost immediately after the event, to victims of accidents
with a number of life-threatening problems (head injury, bleeding from
multiple sources) transferred from other hospitals. Additional complications
PANCREATITIS
29
Fig. 1.18 Management of pancreatic trauma.
Mild injury
clinically well
Mod/severe
injury
clinically well
Severe injury
clinically unwell
No prior
treatment
Late presentation
Suspected
pancreatic
trauma
Urgent
assessment &
classification of
the injury
Early presentation
Previous
treatment/
surgery
Manage
complication(s)
Clinically unwell
Clinically well
Conservative
management
Re-do surgery
Appropriate
surgery
Conservative management
frequent reassessment
surgery for deterioration
Conservative
management
PANCREAS
30
arise when patients are treated conservatively and then deteriorate and are
subsequently transferred. Pancreatic injuries in these circumstances can be
difficult both to accurately assess and treat but appropriate investigations are
helpful. Unlike investigation of the pancreas for malignancy or inflammation,
any significant injury can either be seen directly or inferred from the sequelae
(Bradley et al ., 1998 ). The difficulty lies in interpreting the nature of fluid
collections as blood in a stable patient has a different implication to pancreatic
juice, bile, or duodenal contents. With that proviso, a combination of ultra-
sound and CT scanning generally gives a very accurate account of at least the
presence of free fluid, contained extravasated fluid, pancreatic disruption,
or associated injuries to other organs (liver lacerations, free air from hollow
viscera). This imaging ability has produced (and continues to produce) grad-
ing systems, which while useful to compare results after the management of
the patient, we feel are less useful in guiding urgent clinical decisions (Moore
et al ., 1990 ; Patel SV et al ., 1998 ; Takishima et al ., 2000 ). Some of the grading
schemes also have to be modified if the treatment is delayed more than
24 hours. Finally, even more recent classifications have tried to address
pancreatic, duodenal, and combined injuries separately (Gabriel et al ., 2006 ).
Again this is useful in comparing outcomes but less so in directing the
immediate care.
Classification
Some indication of the severity of the injury is nevertheless valuable. If a sig-
nificant injury can be demonstrated, non-operative management is inappro-
priate. This contrasts with liver trauma and is applicable even in a relatively
stable patient. Our working classification is extremely simple and only patients
with Type 1 injuries to both pancreas and duodenum can be managed con-
servatively ( Table 1.2 ). Delayed presentation or associated injuries to other
viscera should be treated on their merits but our threshold for operating is low
in these patients.
Table 1.2 Classification of pancreatic injuries
Pancreas Duodenum
Type 1 Minimal damage to the capsule or
substance. No free fluid
Bruising. No free fluid or air. No full
thickness injury
Type 2 Laceration to the substance of the gland,
free fluid, likely duct involvement
Full thickness injury seen or free air/
fluid
Type 3 Obvious major injury. Head disruption or
transaction. Inevitable duct damage
Severe injury, disrupted duodenum
with bile duct or gallbladder injury
PANCREATITIS
31
Conservative management
In patients presenting early where the clinical situation is stable and Type 1
duodenal and/or pancreatic injuries are evident, then conservative manage-
ment is appropriate (Rickard et al ., 2005 ). The early presentation also allows
serial investigations to be used to monitor the intra-abdominal injuries (Patel
SV et al ., 1998 ; Lopez et al ., 2005 ; Subramanian et al ., 2007 ). The development
of free fluid or air, even if the patient’s condition does not appear to have
changed dramatically, is an indication for a laparotomy. Delay in patients with
unrecognized pancreatic, duodenal, or biliary leaks is devastating because of
the nature of the leaked material. Current anaesthesia and intensive care facil-
ities mean that a laparotomy does not adversely affect a patient and simple
assessment of injuries, washout, and drainage can produce a significant
improvement and aid recovery.
Surgical management ( Figs. 1.19 – 1.21 )
We recommend surgical intervention in all patients with Type 2 or 3 injuries
to either the duodenum or pancreas ( Table 1.3 ). A worsening clinical state, or
associated injuries to other viscera which require treatment per se, allows the
pancreatic injuries to be examined carefully. The surgical access is by a gener-
ous transverse incision. All clots and debris are removed and a washout per-
formed. Bleeding is identified and initially controlled by packing and any
visceral perforations are closed to prevent contamination. When control of the
bleeding has been achieved a complete laparotomy is performed. This includes
full mobilization of the duodenum and examination of the lesser sac.
The particular areas that may be overlooked are the posterior aspect of the
first and second part of the duodenum and the neck of the pancreas.
Bleeding is then addressed formally and can usually be managed by
direct vascular repair. Only significant portal vein damage will require more
Table 1.3 Management of isolated and combined pancreatic and duodenal injuries
Pancreas
1 2 3
Duodenum
1 Washout and
drainage
Duct assessment. If not
damaged, drain; if involved,
Roux loop
Pancreas repaired
with Roux loop
2 Assessment.
Duodenal repair
and drainage
Assessment of injuries. If
separate, repair and Roux
loop. Together, Whipple’s
Whipple’s
3 Whipple’s Whipple’s Whipple’s
PANCREAS
32
Fig. 1.20 Virtually transected pancreas with clear ductal injury. Bleeding from the
portal vein may be impossible to control until the transection is completed. This
does not affect the reconstruction, which requires Roux loop drainage due to the
duct injury.
Fig. 1.19 Treatment of apparently minor pancreatic injuries in isolation requires a
thorough investigation of ductal integrity.
extensive surgery. Portal vein bleeding is generally, however, associated with
pancreatic transection and if this has not occurred, or is incomplete, will occa-
sionally be required to gain adequate access.
In these cases, the duct is usually already transected and division would
inevitably have been required for repair and reconstruction ( Fig. 1.20 ).
Subsequent approaches to the surgical management or reconstruction depend
on the nature and distribution of the injuries. Duodenal injuries are covered in
Section 2.