Pancreas Flashcards
What are the segments of pancreas
head (neck), body and tail
what are the 2 main tissues of pancreas and their roles
2 main tissues:
- acinar (secretive- makes juice that is secreted into the duodenum) and
- islets of Langerhans (1-2% of all tissues secretes hormones into the blood)
What does pancreatitis affect and what are the consequences?
pancreatitis results in inflammation of the ducts-> impairment of exocrine function (mainly, but endocrine sometimes also takes a hit)
What are the components of exocrine function
- Digestive enzymes (zymogens)
- Bicarbonate ions
in presence of food, particularly fat, CCK stimulates pancreatic contraction this stimulates the release of precursor digestive enzymes- zymogens Zymogens get activated when they get into the duodenum
Bicarb from increases neutralizes chyme
What are the components of endocrine function
- Insulin: beta cells secrete insulin, permitting movement of anabolic nutrients into the cell. hormone
- Glucagon: alpha cells secrete glucagon to stimulate glycogenolysis and gluconeogenesis. Making energy from released fat and AA, triggered by glucagon
- Somatostatin: helps regulate insulin/glucagon e.g., can suppress exocrine function. Can prevent insulin/glucagon secretion
What is pancreatitis
inflammation of pancreas and ducts
What are the manifestations of pancreatitis
1) Inactive forms of pancreatic enzymes are prematurely activated causing autodigestion of pancreatic cells, and elevated enzymes in blood (e.g., lipase);
2) immune cells and cytokines direct an inflammatory response;
3) Increased vascular permeability, causing edema, hemorrhage and necrosis.
What are the potential causes of acute pancreatitis (AP)?
Most common is gallstones, followed by alcohol
High TG can also result in AP
What are the symptoms of AP?
• Upper abdominal pain radiating to back; may worsen with food intake
• Nausea, vomiting, abdominal distention, steatorrhea
• Characterized by edema, cellular exudate, fat necrosis
• Elevated blood levels of pancreatic enzymes (e.g., lipase especially)
• Elevated serum TG
• Elevated liver enzymes in biliary cause
• SIRS/shock, fever→may need to be treated in ICU
• Exudate in peritoneal and pleural spaces
(exudate: any fluid that has exuded from a tissue or capillary due to injury/inflammation)
how is AP diagnosed
- Imaging studies such as CT that will show the exudate
- Blood work: Lipase and amylase at least three times the normal range.
- Lipase rises for 5-7 days
- Amylase rises for 48-72hrs; levels might be below the baseline after this period
why might albumin be low in PA
low albumin is low due to vascular permeability, not nutrition
what are very low albumin levels indicative of?
such low albumin is an indicator of high mortality risk
this also an indicator of high probability of hypovolemia - primary treatment goal
what is low magnesium a sign of
refeeding syndrome
What is the first step in nutritional treatment of AP?
FIRST determine disease severity
• E.g., RANSOM, APACHE II
• Presence of necrotic tissue
energy and protein reccs for AP pts (not obese)
Energy: 25-35kcal/kg (Indirect Calorimetry as it is prefered in ICU pts)
Protein: 1.2-1.5g/kg (ASPEN 1.5g/kg)
energy and protein reccs for AP pts (obese)
Obese: provide EN regimen should at 65%–70% of target energy requirements as measured by IC.
If IC is unavailable:
BMI 30-50: 11–14 kcal/kg actual body weight per day
BMI>50: 30–50 and 22–25 kcal/kg ideal body weight per day
Protein:
BMI 30-40: 2.0 g/kg ideal body weight per day for patients
BMI ≥40: 2.5 g/kg ideal body weight per day for patients
Characteristics of APACHE II <= 9 Ranson’s Criteria <=2
- Degree of Pancreatitis: Mild/moderate
- CT Scan: No necrosis
- Mortality: 0%
- Tolerate PO diet in 7 d: 81%
- Management: supportive
Characteristics of APACHE II >= 10 Ranson’s Criteria >=3
- Degree of Pancreatitis: Severe
- CT Scan: Necrosis
- Mortality: 19%-> high
- Tolerate PO diet in 7 d: 0%-> order NPo straight away
- Management: EN/PN & ICU
will stay in hospital for 1 months or more
Algorithm for Nutrition Management of Acute Pancreatitis
- Evaluate disease severity in ED
a) Mild disease-> admit to ward
i) Advance to oral diet per patient wishes.
ii) Only use EN if oral diet fails over 4 d.
iii) If NG was placed and patient has been tolerating it-> Advance to oral diet per patient wishes.
b) Moderate to Severe Disease: admit to ICU, place NG tube and initiate standard EN if hemodynamically stable
i) If NG was placed and patient has been tolerating it-> Advance to oral diet per patient wishes.
i) If does not tolerate NG EN -> Switch to NJ feeds. Start PN if intolerant > 5d
Firs line of treatment: mild vs severe
Mild: try PO, if not tolerating for 4d-> switch to EN
Severe: NG EN with standard formula straight away
Why would we use diuretics and fluid resuscitation in AP pts
TO get rid of 3rd space fluid as these patients often have edema and ascites
Nutritional Management: Overview for mild acute AP
PO vs EN vs PN depends on severity
• For mild try PO as soon as nausea/vomiting and pain allow- patient lead feeding
• Oral feeds for mild & moderate cases
- Low fat for some, esp biliary issues e.g gallstones
- Aim for SOLID food
• No alcohol
• Frequent small meals (~6/d is commonly tolerated)
• Serum lipase and amylase do not
necessarily correlate with diet
tolerance or AP severity!
• If oral intake fails, initiate EN after 4 days.
Nutritional Management: Overview for severe acute AP
NPO vs EN vs PN depends on severity
• EN within first 48-72 hrs = medical tx
- Make sure hemodynamically stable
• NG
• Standard polymeric formula
• Initiate feeding 25 mL/hour, advance to reach goal over 24-48 hrs
• Intolerance COMMON, thus likely not to tolerate
• If not tolerating-> Next: Try elemental, low fat formula or semi- elemental with MCT
• If not tolerating-> Next: Try NJ
• If all fail within 5 days: PN
• Advance to oral diet when no pain or emesis for 24 h
Why is EN a part of medical treatment?
- Maintain gut integrity, ↓ septic & metabolic complications, ↓ cost
- Reduces stress response vs PN
- Reduces infection
- Reduces hospital stay
- Reduces surgical intervention
- Reduces organ failure
signs of feed intolerance
EN: abdominal signs (distention, tense, discomfort), nausea (check for constipatio, minimize narcotics), emesis (hold feed, check for constipation)
PO: similar signs, but they can also be attributed to other thins->less clear
when can signs of intolerance be observed
when starting or advancing the feed
Additional intolerance signs with AP:
elevated WBC, increased pain, or fever IN ASSOCIATION WITH increases in serum lipase or amylase→ optimize meds → switch to elemental, low fat formula or semi-elemental with MCT
If patient has steatorrhea (it is a sign of maldigestion) →optimize meds → switch to semi elemental with MCT
when are elevated levels of amylase and lipase ok and not ok?
if lipase and amylase increases but no signs of intolerance-> it ok if levels are elevated + signs of intolerance-> sign of not tolerating and a hint to switch formula/method of administration
• Considerations in Nutrition Support with pancreatitis
applicable for acute, mild and severe
• Hyperglycemia and insulin resistance common (40-90% of patients)
- Hypertriglyceridemia (12-15% of cases)
- Electrolyte and micronutrient deficiencies
Considerations in Nutrition Support in pancreatitis: Hyperglycemia and insulin resistance
- Cause: Critical illness and residual Islet function
- Nutrition: Aim for GIR of 3 mg/kg/min if severe pancreatitis with hyperglycemia (not preferable 3. It HAS to be 3 or lower)
- Medical tx: Insulin
Considerations in Nutrition Support in pancreatitis: Hypertriglyceridemia
hyper TG definition: when TG <400 mg/dL (i.e., 4.52 mmol/L in Canada)
• Cause: Hyperglycemia induced and reduced lipoprotein lipase
• Nutrition: Consider GIR of 3 mg/kg/min & <1g fat/kg (HAS to be 1 or
lower)
• Nutrition: Consider source of ILE (Intralipid <30% total kcal)
PO consider low fat and DM diet order (which is already low fat)
Considerations in Nutrition Support in pancreatitis: electrolyte and micronutrient deficiencies
Hypocalcemia in up to 25% of cases
but doesn’t have to be acted upon - no calcium administration is required from you
just aim for higher end of the range for calcium administration in PN/EN
when might you consider MCT?
A. Elevated serum lipase
B. Steatorrhea
C. All of the above
Answer is B
A. Elevated serum lipase is not not correlated to diet
WHy wouldn’t NJ be the first choice of EN administration?
NJ placement is hard and often gets displayed start with NG first, then switch formula NJ would be the last option as it is so hard to place
is NJ with standard formula a good first choice for A?
No, polymeric should be the first choice, especially with NJ
jejunum, but not many do it
going straight to elemental, leaves you with PN only if this approach is not tolerated
Feeds were advanced to 35ml/hr but Mr. C experienced abdominal distension and pain.
What’s the next step?
a. Determine etiology for intolerance
b. Determine if NJ is in the correct position
c. PN
d. All of the above
e. A&B only
e. A&B only
When should PN be initiated?
a. Day 1
b. Day 5 of intolerance to EN
c. Day 7 of intolerance to EN
b. Day 5 of intolerance to EN
Low fat fluids was an appropriate choice as the first PO option offered
A. True B. False
B, false
because we should always aim for solid foods first
What is chronic pancreatitis
irreversible loss of exocrine and endocrine mass by replacement with fibrotic tissue
Nutritional Management: Chronic Pancreatitis
• Main treatment: Replacement enzymes with meals treatment
•Low fat high PRO diet may be indicated - make sure that there are enough
enzymes to digest the fat
• CHO depends on islet function
• MCT oil and EN may be indicated
• No alcohol
• Vitamin supplements (fat soluble)
• may need a diabetic diet if endocrine function has been affected
which enzymes are found in PERT pills
lipase, amylase and protease
which type of drink should be used with PERT
It is important that you swallow your capsules with a cold drink
Hot drinks may damage them and decrease effectiveness
What is the goal in pancreatic insufficiency and nutritional recommendations
Goal: Restore and maintain weight, correct malnutrition
• Frequent, small meals moderate to low in fat
• No research trials of low vs high fat!
• Low fat may exacerbate malnutrition–tolerance is the goal
• Some research on Mediterranean diet
Goal: Improve maldigestion by giving pancreatic enzymes
• Treat with insulin if indicated
Dose calculation for PERT
Initiate PERT with the lowest dose and
increase as needed to control symptoms
If not controlled with that dose-> give a higher dose
2 ways of calculations, but usually per meal calculation is used
Per meal: 500-2500 U lipase/kg/meal
• Do not exceed 2500 U/kg/meal
Max: <10,000 U lipase/kg/d
Per g of fat: 1000-4000 U lipase/1 g dietary fat per day at meals and snacks
PERT instruction for continuous NJ/G
Provide a dose every 3-4 hours
consumption instructions for PERT
• Take with cold drinks
• Take 30 minutes before or with meals
• If pt takes long time to eat-> divide the dose (1/2 in the beginning, 1/2 in the end)
• If uncoated, need to suppress stomach acid (meds like proton pump inhibitors prescribed)
- Used with J-tubes, but not with G- tubes
• Enteric coated (resist degradation by
gastric acid)
- Do not chew
- Requires pH of ~6 to dissolve enteric coat
If your patient weighs 48kg what is the max dose of lipase units she can take per day? A. 500-2500 B. 480,000 C. 1000-4000 D. 10,000
B. 480,000
Max: <10,000 U lipase/kg/d
If your patient weighs 48kg how many units should she take per meal? A. 24,000-120,000 B. 500-2500 C. 10,000 D. 480,000
A. 24,000-120,000
If your patient weighs 48kg and is taking Creon with 6000 units lipase per capsule. How many capsules does she need to take to cover her meal?
A. 10,000
B. 4-20
C. 10-22
D. 3
B. 4-20
48500/6000
482500/6000
How do you know the lipase dose is sufficient? A. Weight is stable B. Steatorrhea absent C. Bloating, cramping, gas absent D. All of the above
D. All of the above
note: steatorrhea volume should go down, but it rarely goes away fully
WHY do patients need pancreatic surgery?
- Cancer
- Necrosis secondary to AP
- Assist with control of symptoms associated with CP
• Most common pancreatic surgery procedure
= Whipple • AKA pancreaticoduodenectomy
HOW do we prepare patients for pancreatic surgery?
- Screen and assess for malnutrition or other nutrition-related problems
- Treat the problems so that patient is prepared to withstand the stress of surgery!
- Consider ONS for 7 days before surgery: Not always enough time for food first approach!
- CHO loading 2 hours before surgery
what do u have to include in the follow up note
Is the previous nutritional diagnosis still relevant, improved, worsened?
what does Whipple procedure involve?
Removal of head of pancreas, distal bile duct, gallbladder, duodenum, distal stomach, and first few cm of jejunum
what determines the extent of loss of endocrine/exocrine function in whipple?
extent of pancreatic loss determines the extent of loss of endocrine/exocrine function
but there always be loss
Gastrojejunostomy vs Hepaticojejunostomy vs Pancreaticojejunostomy
A hepaticojejunostomy is the surgical creation of a communication between the hepatic duct and the jejunum; a choledochojejunostomy is the surgical creation of a communication between the common bile duct and the jejunum
Gastrojejunostomy is a surgical procedure in which an anastomosis is created between the stomach and the proximal loop of the jejunum
• can either have intact or absent pylorus
Pancreaticojejunostomy is a surgical formation of an artificial passage connecting the pancreas to the jejunum.
after whipple, what flows directly into the jejunum
bile, pancreatic enzymes and stomach contents flow directly into jejunum
How should we feed this patient immediately postop?
ERAS-> solid food/regular diet but slow with small amounts
Institution specific: NPO → Liquids → Solid food
Sometimes surgeon will place J-tube for prolonged EN support; Esp, if malnourished preop.
Note: Pancreatic leaks require NPO and PN
Whipple: Nutritional implications and treatment
• Surgery alters motility, digestion, and absorption.
- 95% will have exocrine pancreatic insufficiency (EPI)-> dietary fat and fat-soluble vitamin malabsorption
- Tx: Typically initiate PERT after surgery
• If endocrine insufficiency, insulin is the treatment
• Motility
• Does the patient have pylorus? If not,
expect dumping syndrome-> anti-dumping diet
• If patient does have pylorus, may experience delayed gastric emptying or gastroparesis
What are ERAS reccs after surgery
what are usual approaches in practice?
- pt should be allowed normal diet post surgery with no restrictions
- increase intake according to tolerance over 3-4 days
In practice, often NPO →CF/FF fluids → solid food by day 4-5. Patients are not discharged from hospital until can tolerate PO.
post-discharge diet
- Instruct patient on high kcal, high protein diet divided into frequent small meals
- Do not recommend low fat diet => just prescribe PERT
- Make sure patient understands how to adjust PERT based on fat intake
- May require diabetes education if on insulin tx or high BG.
- Tx symptoms that arise, such as dumping or nausea.
- Pt is POD 1 of a Whipple procedure. Surgeon surgically placed J-tube during procedure.
- Wt: 51kg; BMI: 18
- SGA: C
- Energy needs are estimated as 30kcal/kg and 1.2g protein/kg.
- 1) Calculate a J-tube feeding for this patient using a semi- elemental formula known as Vital 1 cal. Include, goal, initiation and advancement rate. What is your nutrition prescription statement?
- 2) Calculate PERT for this patient.
1530kcal
61.2g of protein required
7 bottles: 1540kcal, 63g fluid: in the formula- 1314, needs 1540 1540-1314=226ml left for flushes 226/6= 38 ml per flush-> 35-40ml per flush give a flush every 4h
Continuous feed for max tolerance- good starting point, especially considering that the tube is in the jejunum
Statement: initiate a 24h continuous NJ feed with 7 bottles of Vital 1cal. via a pump at 25ml/h and increase by 10ml q 8hours as tolerated until goal rate of 64ml/hr. At goal this will provide 1540kcal (30.2kcal/kg which meets estimated needs), 63g of protein (1.2g/kg).
Administer 35ml flushes every 4 hours, providing a total water intake of 1524ml/day, which is 30ml/kg meeting estimated needs
lipase prescription: 500*51=25500U/meal
total g of fat = 7 bottles 8g per bottle= 56
561000=56000, check if lowest dose works
with continuous feed, administer every 3-4 hours-> divide this dose 9333U per day every 4 hours- round to practical amount of 10000U every 4 hours
when should EN be adminsitered in those, who require it?
within 48-72 hours of admission
Enteral Formula Selection in Severe Acute Pancreatitis
- Standard polymeric formula may be used in most patients.
- If patient has signs of intolerance (increased pain, fever, or white blood cell count in association with increases in serum amylase and serum lipase), switch to elemental, very low–fat formula or switch to a semi-elemental formula with small peptides and medium-chain triglycerides.
- If patient has signs of malassimilation (diarrhea and/or steatorrhea), switch to semi-elemental formula with small peptides and MCT
