1. For the Surgical Patient
Nutrition
For the Surgical Patient
Kelly Sparks LDN, RD

2. Lecture Outline Energy Sources Nutrition Requirements Diet Advancement
Micronutrients for wound healing
Enteral versus Parenteral Nutrition
Case studies

3. Energy Sources Carbohydrates Fats Protein
Limited storage capacity, needed for CNS function
Yields 3.4 kcal/gram
Pitfall: too much=lipogenesis and increased CO2 production
Fats
Major endogenous fuel source in healthy adults
Yields 9 kcal/gm
Pitfall: too little=essential fatty acid (linoleic acid deficiency-dermatitis and increased risk of infections
Protein
Needed to maintain anabolic state (match catabolism)
Yields: 4 kcal/gm
Pitfall: must adjust in patient with renal and hepatic failure
Elevated creatinine, BUN, and/or ammonia

4. Nutrition Requirements
Healthy Adults
Calories: kcals/kg
Protein: gm/kg
Fluids: 30 mls/kg
Requirement Change for the Surgical Patient
Special Considerations
Stress
Injury or disease
Surgery
Pre-hospital/pre-surgical nutrition

5. Nutrition The surgical patient… Poor Nutrition=Poor Outcomes
Extraordinary stressors (hypovolemia, hypervolemia, bacteremia, medications)
Wound Healing
Anabolic state, appropriate vitamins (A, C, Zinc), and adequate kcals/protein.
Poor Nutrition=Poor Outcomes
For every gram deficit of untreated hypoalbuminemia there is ~30% increase in mortality

6. Post-Operative Nutrition Requirements
Calories:
Increase to kcals/kg
Patient on ventilator usually require less
calories ~20-25 kcal/kg
Protein:
Increase to grams/kg
Fluids:
Individualized

7. Diet Advancement Traditional Method:
Start clear liquids when signs of bowel function returns.
Rationale: Clear liquid diets supply fluid and electrolytes in a form that require minimal digestion and little stimulation of the GI tract.
Clear liquids are intended for short-term use due to inadequacy

8. Diet Advancement Recent Evidence: Clinical study:
Suggests that liquid diets and slow diet progression may not be warranted!!
Clinical study:
Looked at early post-operative feeding using regular diets or very fast progression vs. traditional methods of NPO until bowel function with slow diet progression and found no difference in post-operative complications. (emesis, distention, NGT reinsertion, LOS,)

9. Keep in Mind…
Per SLP
When using liquid diets, patients must have adequate swallowing functions.
Even patients with mild dysphagia often require thickened liquids.
Therefore, be specific in writing liquid diet orders for patients with dysphagia

10. Micronutrients in Wound Healing
Vitamin Supplementation to promote healing has been somewhat disputed.
Some studies show no significant effect unless there is a clinical vitamin deficiency
Serum vitamin levels are not always accurate; therefore, must use subjective diet history and clinical judgment to determine deficiency.

11. Key Nutrients for Wound Healing
Vitamin A:
Cellular differentiation, proliferation, epithelialization,
collagen synthesis, counteract catabolic effect of steroids.
RDA=3333 International Units
Appropriate dose=25,000 IU per day x 10 days in setting of high dose steroids or deficiency.
Avoid long term supplementation due to high risk of toxicity with fat-soluble vitamins.
No vitamin A with renal failure due to greater potent ional for toxicity. (Can exceed the binding capacity of retinol binding protein leading to elevated circulating levels.)

12. Key Nutrients for Wound Healing
Vitamin C:
Collagen synthesis
RDA=50-90 mg/day
Low levels are common in high risk population (elderly, smokers, cancer, liver disease).
Appropriate dose: 500 mg x 10 days
No vitamin C with renal failure due to risk for renal oxalate stone formation.

13. Key Nutrients for Wound Healing
Zinc:
Protein synthesis, cellular replication, collagen formation; large wounds, chest tubes, and wound drains contribute to further zinc loses.
Appropriate dose: 220 mg per day of Zinc Sulfate or
50 mg of elemental Zinc x 10 days.
Prolonged Zinc supplementation interferes with copper absorption and can lead to copper deficiency which delays wound healing by impairing collagen synthesis.
MVI with minerals:
1 tablet daily to compensate for any general micronutrient losses.

14. What is nutrition support?
An alternate means of providing nutrients to people who cannot eat any or enough food
When is it needed?
Illness resulting in inability to take in adequate nutrients by mouth
Illness or surgery that results in malfunctioning gastrointestinal tract
Two types:
Enteral nutrition
Parenteral nutrition

15. Indications for Enteral Nutrition
Malnourished patient expected to be unable to eat adequately for > 5-7 days
Adequately nourished patient expected to be unable to eat > 7-9 days
Adaptive phase of short bowel syndrome
Following severe trauma or burns

16. Contraindications to Enteral Nutrition Support
Malnourished patient expected to eat within 5-7 days
Severe acute pancreatitis
High output enteric fistula distal to feeding tube
Inability to gain access
Intractable vomiting or diarrhea
Aggressive therapy not warranted
Expected need less than 5-7 days if malnourished or 7-9 days if normally nourished

17. Enteral Access Devices
Nasogastric
Nasoenteric
Gastrostomy
PEG (percutaneous endoscopic gastrostomy)
Surgical or open gastrostomy
Jejunostomy
PEJ (percutaneous endoscopic jejunostomy)
Surgical or open jejunostomy
Transgastric Jejunostomy
PEG-J (percutaneous endoscopic gastro-jejunostomy)
Surgical or open gastro-jejunostomy

18. Feeding Tube Selection
Can the patient be fed into the stomach, or is small bowel access required?
How long will the patient need tube feedings?

19. Gastric vs. Small Bowel Access
“If the stomach empties, use it.”
Indications to consider small bowel access:
Gastroparesis / gastric ileus
Recent abdominal surgery
Sepsis
Significant gastroesophageal reflux
Pancreatitis
Aspiration
Ileus
Proximal enteric fistula or obstruction

20. Short-Term vs. Long-Term Tube Feeding Access
No standard of care for cut-off time between short-term and long-term access
However, if patient is expected to require nutrition support longer than 6-8 weeks, long-term access should be considered

21. Choosing Appropriate Formulas
Categories of enteral formulas:
Polymeric (Jevity)
Whole protein nitrogen source, for use in patients with normal or near normal GI function
Monomeric or elemental (Perative, Optimental)
Predigested nutrients; most have a low fat content or high % of MCT oil (medium-chain triglycerides); for use in patients with severely impaired GI function
Disease specific (Nepro, Nutrahep, Glucerna)
Formulas designed for feeding patients with specific disease states
Formulas are available for respiratory disease, diabetes, renal failure, hepatic failure, and immune compromise
*well-designed clinical trials may or may not be available

22. Enteral Nutrition Prescription Guidelines
Gastric feeding
Continuous feeding:
Start at rate 30 mL/hour
Advance in increments of 20 mL q 8 hours to goal
Check gastric residuals q 4 hours
Bolus feeding:
Start with mL bolus
Increase by 60 mL q bolus to goal volume
Typical bolus frequency every 3-8 hours
Small bowel feeding
Continuous feeding only; do not bolus due to risk of dumping syndrome
Start at rate 20 mL/hour
Do not check gastric residuals

23. Aspiration Precautions
To prevent aspiration of tube feeding, keep HOB > 30° at all times
Do not use methylene blue to test for aspiration; regular blue food dye OK but not proven effective method of detecting aspiration

24. Complications of Enteral Nutrition Support
Nausea and vomiting / delayed gastric emptying
Malabsorption
Common manifestations include unexplained weight loss, steatorrhea, diarrhea
Potential causes include gluten sensitive enteropathy, Crohn’s disease, radiation enteritis, HIV/AIDS-related enteropathy, pancreatic insufficiency, short gut syndrome

25. Enteral Nutrition Case Study
78-year-old woman admitted with new CVA
Significant aspiration detected on bedside swallow evaluation and confirmed with modified barium swallow study; speech language pathologist recommended strict NPO with alternate means of nutrition
PEG placed for long-term feeding access
Plan of care is to stabilize the patient and transfer her to a long-term care facility for rehabilitation

26. Enteral Nutrition Case Study (continued)
Height: 5’4” IBW: 120# +/- 10%
Weight: 130# / 59kg % IBW
BMI: 22
Usual weight: ~130# no weight change
Estimated needs:
kcal (25-30 kcal/kg)
59-71g protein (1-1.2 g/kg)
1770 mL fluid (30 mL/kg)

27. Steps to determine the Enteral Nutrition Prescription
Estimate energy, protein, and fluid needs
Select most appropriate enteral formula
Determine continuous vs. bolus feeding
Determine goal rate to meet estimated needs
Write/recommend the enteral nutrition prescription

28. Enteral Nutrition Prescription
Tube feeding via PEG with full strength
Jevity 1.2
Initiate at 30 mL/hour, advance by 20 mL q 8 hours to goal
Goal rate = 55 mL/hour continuous infusion
Above goal will provide 1584 kcal, 73g protein, 1069 mL free H2O
Give additional free H2O 175 mL QID to meet hydration needs and keep tube patent
Check gastric residuals q 4 hours; hold feeds for residual > 200 mL
Keep HOB > 30° at all times

29. What is parenteral nutrition?
also called "total parenteral nutrition," "TPN," or "hyperalimentation."
It is a special liquid mixture given into the blood via a catheter in a vein.
The mixture contains all the protein, carbohydrates, fat, vitamins, minerals, and other nutrients needed.

30. Indications for Parenteral Nutrition Support
Malnourished patient expected to be unable to eat > 5-7 days AND enteral nutrition is contraindicated
Patient failed enteral nutrition trial with appropriate tube placement (post-pyloric)
Enteral nutrition is contraindicated or severe GI dysfunction is present
Paralytic ileus, mesenteric ischemia, small bowel obstruction, enteric fistula distal to enteral access sites

31. PPN vs. TPN TPN (total parenteral nutrition)
High glucose concentration (15%-25% final dextrose concentration)
Provides a hyperosmolar formulation ( mOsm/L)
Must be delivered into a large-diameter vein through central line.
PPN (peripheral parenteral nutrition)
Similar nutrient components as TPN, but lower concentration (5%-10% final dextrose concentration)
Osmolarity < 900 mOsm/L (maximum tolerated by a peripheral vein)
May be delivered into a peripheral vein
Because of lower concentration, large fluid volumes are needed to provide a comparable calorie and protein dose as TPN

32. Parenteral Access Devices
Peripheral venous access
Catheter placed percutaneously into a peripheral vessel
Central venous access (catheter tip in SVC)
Percutaneous jugular, femoral, or subclavian catheter
Implanted ports (surgically placed)
PICC (peripherally inserted central catheter)

33. Writing TPN prescriptions
Determine total volume of formulation based on individual patient fluid needs
Determine amino acid (protein) content
Adequate to meet patient’s estimated needs
Determine dextrose (carbohydrate) content
~70-80% of non-protein calories
Determine lipid (fat) content
~20-30% non-protein calories
Determine electrolyte needs
Determine acid/base status
Check to make sure desired formulation will fit in the total volume indicated

34. Parenteral Nutrition Monitoring
Check daily electrolytes and adjust TPN/PPN electrolyte additives accordingly
Check accu-check glucose q 6 hours (regular insulin may be added to TPN/PPN bag for glucose control as needed)
Non-diabetics or NIDDM: start with half of the previous day’s sliding scale insulin requirement in TPN/PPN bag and increase daily in the same manner until target glucose is reached
IDDM: start with 0.1 units regular insulin per gram of dextrose in TPN/PPN, then increase daily by half of the previous day’s sliding scale insulin requirement
Check triglyceride level within 24 hours of starting TPN/PPN
If TG > mg/dL, lipid infusion should be significantly reduced or discontinued
Consider adding carnitine 1 gram daily to TPN/PPN to improve lipid metabolism
~100 grams fat per week is needed to prevent essential fatty acid deficiency

35. Parenteral Nutrition Monitoring (continued)
Check LFT’s weekly
If LFT’s significantly elevated as a result of TPN, then minimize lipids to < 1 g/kd/day and cycle TPN/PPN over 12 hours to rest the liver
If Bilirubin > 5-10 mg/dL due to hepatic dysfunction, then discontinue trace elements due to potential for toxicity of manganese and copper
Check pre-albumin weekly
Adjust amino acid content of TPN/PPN to reach normal pre-albumin mg/dL
Adequate amino acids provided when there is an increase in pre-albumin of ~1 mg/dL per day

36. Parenteral Nutrition Monitoring (continued)
Acid/base balance
Adjust TPN/PPN anion concentration to maintain proper acid/base balance
Increase/decrease chloride content as needed
Since bicarbonate is unstable in TPN/PPN preparations, the precursor—acetate—is used; adjust acetate content as needed

37. Complications of Parenteral Nutrition
Hepatic steatosis
May occur within 1-2 weeks after starting PN
May be associated with fatty liver infiltration
Usually is benign, transient, and reversible in patients on short-term PN and typically resolves in days
Limiting fat content of PN and cycling PN over 12 hours is needed to control steatosis in long-term PN patients

38. Complications of Parenteral Nutrition Support (continued)
Cholestasis
May occur 2-6 weeks after starting PN
Indicated by progressive increase in TBili and an elevated serum alkaline phosphatase
Occurs because there are no intestinal nutrients to stimulate hepatic bile flow
Trophic enteral feeding to stimulate the gallbladder can be helpful in reducing/preventing cholestasis
Gastrointestinal atrophy
Lack of enteral stimulation is associated with villus hypoplasia, colonic mucosal atrophy, decreased gastric function, impaired GI immunity, bacterial overgrowth, and bacterial translocation
Trophic enteral feeding to minimize/prevent GI atrophy

39. Parenteral Nutrition Case Study
55-year-old male admitted with small bowel obstruction
History of complicated cholecystecomy 1 month ago. Since then patient has had poor appetite and 20-pound weight loss
Patient has been NPO for 3 days since admit
Right subclavian central line was placed and plan noted to start TPN since patient is expected to be NPO for at least 1-2 weeks

40. Parenteral Nutrition Case Study (continued)
Height: 6’0” IBW: 178# +/- 10%
Weight: 155# / 70kg % IBW
BMI: 21
Usual wt: 175# % wt loss x 1 mo.
Estimated needs:
kcal (30-35 kcal/kg)
84-98g protein ( g/kg)
mL fluid (30-35 mL/kg)

41. Parenteral Nutrition Prescription
TPN via right-SC line
2200 mL total volume x 24 hours
Amino acid: 45 g/liter=
45g x 2.2 L= 99 grams x 4 kcals/gram =369 kcals
Dextrose 175 g/liter=
175g x 2.2 L= 385 grams x 3.4 kcals/gram= 1309 kcals
Lipid 20% 285 mL over 24 hours
285 mls x 2= 570 kcals
Above will provide 2275 kcal, 99g protein,
DIR=(385 g dex/ 70 kg /1440 minute in a day)*1000= 3.8mg/kg/min
LIR= (285 mls lipid * 20%)/ 70 kg=0.8 g/kg/day

42. Parenteral Nutrition Prescription
Important items to consider:
Dextrose infusion rate should be < 4 mg/kg/minute (maximum tolerated by the liver) to prevent hepatic steatosis
Lipid infusion rate should be less than 1 g/kg/day to minimize/prevent TPN-induced liver dysfunction
You may need to adjust/eliminate lipids if patient is on propofol. (1 ml propofol =1.1 kcal)
Ex. 10 ml/hr would provide 264 kcals
(10 ml/hr x 1.1 kcal/ml, x 24 hrs)
Initiate TPN at ~½ of goal rate/concentration and gradually increase to goal over 2-3 days to optimize serum glucose control

43. Benefits of Enteral Nutrition Over Parenteral Nutrition
Cost
Tube feeding cost ~ $10-20 per day
TPN costs up to $1000 or more per day!
Maintains integrity of the gut
Tube feeding preserves intestinal function; it is more physiologic
TPN may be associated with gut atrophy
Less infection
Enteral feeding—very small risk of infection and may prevent bacterial translocation across the gut wall
TPN—high risk/incidence of infection and sepsis

44. Refeeding Syndrome
“the metabolic and physiologic consequences of depletion, repletion, compartmental shifts, and interrelationships of phosphorus, potassium, and magnesium…”
Severe drop in serum electrolyte levels resulting from intracellular electrolyte movement when energy is provided after a period of starvation (usually > 7-10 days)
Physiologic and metabolic sequelae may include:
EKG changes, hypotension, arrhythmia, cardiac arrest
Weakness, paralysis
Respiratory depression
Ketoacidosis / metabolic acidosis

45. Refeeding Syndrome (continued)
Prevention and Therapy
Correct electrolyte abnormalities before starting nutrition support
Continue to monitor serum electrolytes after nutrition support begins and replete aggressively
Initiate nutrition support at low rate/concentration (~ 50% of estimated needs) and advance to goal slowly in patients who are at high risk

46. Consequences of Over-feeding
Risks associated with over-feeding:
Hyperglycemia
Hepatic dysfunction from fatty infiltration
Respiratory acidosis from increased CO2 production
Difficulty weaning from the ventilator
Risks associated with under-feeding:
Depressed ventilatory drive
Decreased respiratory muscle function
Impaired immune function
Increased infection

47. Questions
Reference:
American Society for Parenteral and Enteral Nutrition. The Science and Practice of Nutrition Support
Han-Geurts, I.J, Jeekel,J.,Tilanus H.W, Brouwer,K.J., Randomized clinical trial of patient-controlled versus fixed regimen feeding after elective abdominal surgery. British Journal of Surgery. 2001, Dec;88(12):
Jeffery K.M., Harkins B., Cresci, G.A., Marindale, R.G., The clear liquid diet is no longer a necessity in the routine postoperative management of surgical patients. American Journal of Surgery.1996 Mar; 62(3):167-70
Reissman.P., Teoh, T.A., Cohen S.M., Weiss, E.G., Nogueras, J.J., Wexner, S.D. Is early oral feeding safe after elective colorectal surgery? A prospective randomized trial. Annals of Surgery July;222(1):73-7.
Ross, R. Micronutrient recommendations for wound healing. Support Line. 2004(4): 4.