Intestinal failure is the impairment of absorptive capacity, needing prolonged fluid/nutrition support to maintain health

Acute - days-weeks; during chemo or radiation therapy

Chronic - Months to years

Short Bowel Syndrome:

Up to 50% of bowel can be removevd with no consequences, SBS usually occurs after surgical resections, thrombosis resulting in intestinal infarction, malignancy, or volvulus

- Extent of the resection --> <80% is best

- Site --> Jejunum resection is best (Ileum can take over a lot of functions)

- Concomittant Disease --> No disease is best of course

- Duration --> > one year (what?)

- Antatomy of GI tract --> Presence of ileocecal valve and colon.  Valve stops food from moving backwards, and colon helps reabsorb electrolytes and fluids

- We want site to be at jejunem, so removing it doesn't affect too much, also want presence of ileocecal valve and colon, so bacteria doesn't infect GI tract.

- If jejunum was removed, and remaining length is <120cm and no colon, give TPN.  If jejunum removed and there IS colon, give TPN but <60cm is adequate. 

- Adaptation can occur as early as 1-2 days after resection, could take 1-2 YEARS, so keep giving nutrients

- Colon is needed for water/electrolyte exchange

- Long term/home nutrition support:  enteral, parenteral, or both

Surgery makes you shed a TEAR

- Transplantation

- End-end lengthening procedures

- Antiperistaltic segments

- Recirculating loops

Two types of individuals:  Absorbers and Secretors

Absorbers - Take in more nutrients/fluids than they lose, managed by po nutrient/electrolyte support

Secretors - Have more output than intake (usually <100cm intestine remaining), absorb only 35% of po, NEED IV SUPPORT

- Codeine and loperamide are motility agents

- 15-30mg of codeine 30 min.  before meals, reduces motility and secretions

- 4mg of loperamide 30 min. before meals, may need to break open capsules so they are absorbed

- H2 blockers or PPI's may also reduce gastric acid production and reduce overall fluid loss.

- Octreotide (Sandostatin)

- Octapeptide of endogenous somatostatin

- Blocks release of serotonin and other peptides like glucagon, gastrin, VIP, and insulin

- Increases Na and water reabsorption, so dec. diarrhea

- Start at 50mcg bid, then titrate upwards to 500mcg q8h

- IM sandostatin is NOT for this same indication

- Dose 10mcg/kg/dose or IV q12h

- ADR's: short term n/v, diarrhea, abd. pain, long term gallstones

- Suppresses tropic stimulation so avoid in early post-resection patients

- May reduce fat abs. messes with blood sugar, flushing, lightheadedness, headache

- Stimulates bowel adaption, may be combined with glutamine, enhances nutrient absorption

- Dose 0.1mg/kg/day sc for four weeks in PN patients who are stable and have optimal diet and medication therapy 6-24 months after bowel resection

- Timing and appropriateness remains controversial

- 2-4g/day

- may enhance GI mucosal integrity and improve the health of the enterocyte, thereby improving absorption

- How do we know drug is being absorbed?

- need to know PK of the drug, part of intestine that needs to absorb it

- Rectal administration no good, as patient has diarrhea

- length of intestine, mucosal integrity, intestinal motility all plays a role

- Fat soluble or water soluble drug

- Physiological req. for abs.; Acidic (penicillin, ketoconazole), alkaline (procainamide, nitrofurantoin), bile acids needed (Cyclosporin A, D2, squinavir), ileal absorption (B12)

- Patient has low protein stores which can effect drug delivery

- No slow or timed release formulations, caution with EC, parenteral is an option, aerosol, topical.

- Once nutrients are absorbed they are handled normally

- Carb malabsorption leads to diarrhea (lactose intolerance)

- For protein absorption, peptides are more easily absorbed than free amino acids

- Fat absorbption most affected in SBS

- Impaired bile salt recycling may lead to gallstones

- Fat can be provided as MCT, but needs LCT b/c we need essential fatty acids as well

- If dehydrated a patient will develop metabolic alkalosis and excrete more K+

- In jejunostomy patients with output of 1.5-21 (is this second number right?), give high NA solution (120meq/glucose 110mmol), low Na draw water out of people

- K+ replacement is only needed if jejunum <50cm and ostomy is present)

- Urine with Na <5meq/L is indicative of Na depletion

- Avoid tea, coffee, water

- Avoid liquids 30 min. before and after meals

- D2 can cure magnesium deficiency, 1-4g of calcium/day should fix this deficiency

- Normal pH 7.4

- H+ and Cl- are lost in ostomy, diarrhea, urine losses

- If colon is present but diarrhea is still there, K+ and HcO3 will be lost, leading to metabolic acidosis

Duodenum - Calcium, Iron, CHO, fat, Mg, protein

Jejunum - CHO, fat, AA, Mg, copper, zinc, folate, Phosphorous

Ileum - Fat, Mg, Protein, Phosphorous

Terminal Ileum - B12, bile salts

Colon - Water and electrolytes

- Most water soluble vitamins absorbed in the jejunum so not usually a problem

- If ileal resection >60cm, need B12

- If there is fat malabsorption then we need fat soluble vitamins (ADEK)

- Aqueous form of Vitamin E in PEG may have better absorption po in SBS

- Folate and B12 deficiency can lead to anemia

Hypovolemia  --> Increase fluids intake

Hypervolemia --> decrease fluids, diuretics

Hyponatremia --> Replace Na when indicated, diuresis prn

Hypernatremia - Rehydrate as needed, check for sources of Na

Hypokalemia --> Increase K+ intake

Hyperkalemia --> Check sources of K+, correct acidosis

Hypophosphotemia --> Increase P intake, d/c binders

Hyperphosphotemia --> Decrease P intake

Hypomagnesemia --> Increase Mg intake

Hypermagnesemia --> Decrease Mg intake

Hyperglycemia --> Reduce dextrose load, give insulin

Hypoglycemia --> Taper infusion, increase dextrose load

Resp. Acidosis --> Dec. dextrose, inc. fat kcal

Elevated chol. and triglycerides --> dec. fat or d/c if TG>300

Abnormal LFT, raised ALP, AST, Bili --> Decrease kcal, dex., provide essential FA's

Altered AA profile --> Change solution or decrease AA intake

- Hyperglycemia and insulin resistance is common

- Hyperkalemia

- Increased serum P and Mg

- Zinc and Copper removed via dialysis, as well as WS vitamins

- Use concentrated macronutrient solutions, keep TG's below 300

- Less likely than ARF to develop glycemic problems

- Protein req. depend on dialysis

- Na is often low --> control with dialysis

- K+ usually high

- WS vits are decreased, FS are ok, vitamin A may be high

- Insulin resis. is common

- TG are elevated

- Aromatic AA accumulate

- Branched AA decrease b/c of metabolism by skeletal muscle

- Na and water retention is common

- K+ and Mg is decreased

- Zinc --> lost in diarrhea

- Copper and Manganese not excreted --> should be held

- Hypermetabolism common in COPD

- Formula should be 60% fat, need to keep glucose load moderate to low as metabolism can lead to dioxide production which is difficult to excrete with lung issues

- Avoid over-feeding

- Keep patient slightly dry

- Make sure serum phosphate is adequate