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