Nutrition

1. Nutrition . . . and the surgical patient Carli Schwartz, RD/LDN

2. Nutrition and Surgery • Malnutrition may compound the severity of complications related to a surgical procedure • A well-nourished patient usually tolerates major surgery better than a severely malnourished patient • Malnutrition is associated with a high incidence of operative complications and death.

3. Normal Nutrition (EatRight.org)

4. Nutrition • Carbohydrates • Limited strorage capacity, needed for CNS (glucose) function • Yields 3.4 kcal/gm • Recommended 45-65% total daily calories.

5. Nutrition • Fats • Major endogenous fuel source in healthy adults • Yields 9 kcal/gm • Too little can lead to essential fatty acid (linoleic acid) deficiency and increased risk of infections • Recommended 20-30% of total caloric intake

6. Nutrition • Protein • Needed to maintain anabolic state (match catabolism) • Yields 4 kcal/gm • Must adjust in patients with renal and hepatic failure • Recommended 10-35% of total caloric intake.

7. Normal Nutrition • Requirements • HEALTHLY male/female • (weight maintenance) • Caloric intake=25-30 kcal/kg/day • Protein intake=0.8-1gm/kg/day (max=150gm/day) • Fluid intake=~ 30 ml/kg/day

8. Nutrition • Requirements ? SURGICAL PATIENT ?

9. Special considerations • Stress • Injury or disease • Surgery • Pre-hospital/pre-surgical nutrition • Nutrition history

10. The surgical patient . . . . • Increased risk of malnutrition due to: • Inadequate nutritional intake • surgical stress • subsequent increase in metabolic rate. • Extraordinary stressors (hypovolemia, bacteremia, medications) • Wound healing • Anabolic state, appropriate vitamins • Poor nutrition=poor outcomes • For every gm deficit of untreated hypoalbuminemia there is ~ 30% increase in mortality

11. Nutrition HEALTHLY 70 kg MALE Caloric intake 25-30 kcal/kg/day Protein intake 0.8-1gm/kg/day (max=150gm/day) Fluid intake 30 ml/kg/day SURGERY PATIENT Caloric intake *Mild stress, inpatient 25-30 kcal/kg/day *Moderate stress, ICU patient 30-35 kcal/kg/day *Severe stress, burn patient 30-40 kcal/kg/day Protein intake 1-2 gm/kg/day Fluid intake INDIVIDUALIZED

12. Measures of success:serum markers • Albumin • Synthesized in and catabolized by the liver • Pro: often ranked as the strongest predictor of surgical outcomes- inverse relationship between postoperative morbidity and mortality compared with preoperative serum albumin levels • Con: lack of specificity due to long half-life (approximately 20 days). • Normal range: 3.5-5 g/dL. • The National Veterans Affairs Surgical Risk Study evlauated 87,000 noncardiac surgeries in 44 Veteran’s Administration medical centers and found preoperative serum albumin to the bet strongest predictor of postoperative mortality

13. Measures of success:serum markers (cont’d) • Prealbumin (transthyretin)- transport protein for thyroid hormone, synthesized by the liver and partly catabolized by the kidneys. • Normal range:16 to 40 mg/dL; values of <16 mg/dL are associated with malnutrition. • Levels may be increased in the setting of renal dysfunction, corticosteroid therapy, or dehydration, whereas physiological stress, infection, liver dysfunction, and over-hydration can decrease prealbumin levels.[8,30,37] • Pro: Shorter half life (two to three days) making it a more favorable marker of acute change in nutritional status. A baseline prealbumin is useful as part of the initial nutritional assessment if routine monitoring is planned. • Cons: More expensive than albumin. • Reasonable goal would be to increase prealbumin by 3-5 mg/dL/wk until values are within normal limits.[This goal would be valid only in the absence of other factors that can influence prealbumin (Elevated concentrations of C-reactive protein (>10 mg/dL) suggest physiological stress that requires continued hepatic synthesis of acute-phase reactants and delays production of markers of nutritional rehabilitation, such as prealbumin. Until this stress response subsides, practitioners may not see improvement in prealbumin levels no matter how much nutrition is being provided)

14. Measures of success:serum markers (cont’d) • Transferrin: acute-phase reactant and a transport protein for iron • normal range: 200 to 360 mg/dL. • Medium half-life (8-10 days) • influenced by several factors, including liver disease, fluid status, stress, and illness. • Levels decrease in the setting of severe malnutrition, however unreliable in the assessment of mild malnutrition, • Cons: not studied extensively as albumin and prealbumin in relation to nutritional status, can be expensive.

15. Other measures of success • Nitrogen balance • Protein ~ 16% nitrogen • Protein intake (gm)/6.25 - (UUN +4)= balance in grams • Positive value: found during periods of growth, tissue repair or pregnancy. This means that the intake of nitrogen into the body is greater than the loss of nitrogen from the body, so there is an increase in the total body pool of protein. • Negative value: can be associated with burns, fevers, wasting diseases and other serious injuries and during periods of fasting. This means that the amount of nitrogen excreted from the body is greater than the amount of nitrogen ingested. • Healthy Humans= Nitrogen Equilibrium • Metabolic cart (indirect calorimetry) • ICU patient, measure of exchange of O2 and CO2 • Respiratory quotient =1

16. Postoperative Nutritional Care • Traditional Method: Diet advancement • Introduction of solid food depends on the condition of the GI tract. • Oral feeding delayed for 24-48 hours after surgery • Wait for return of bowel sounds or passage of flatus. • Start clear liquids when signs of bowel function returns • Rationale • Clear liquid diets supply fluid and electrolytes that require minimal digestion and little stimulation of the GI tract • Clear liquids are intended for short-term use due to inadequacy

17. Things to Consider… • For liquid diets, patients must have adequate swallowing functions • Even patients with mild dysphagia often require thickened liquids. • Must be specific in writing liquid diet orders for patients with dysphagia • There is no physiological reason for solid foods not to be introduced as soon as the GI tract is functioning and a few liquids are being tolerated. Multiple studies show patients can be fed a regular solid-food diet after surgery without initiation of liquid diets.

18. Diet Advancement • Advance diet to full liquids followed by solid foods, depending on patient’s tolerance. • Consider the patient’s disease state and any complications that may have come about since surgery. • Ex: steroid-induced diabetes in a post-kidney transplant patient.

19. Patients who cannot eat . . . ? Consider Nutrition Support!

20. Nutrition Support • Length of time a patient can remain NPO after surgery without complications is uknown, however depends on: • Severity of operative stress • Patient’s preexisting nutritional status • Nature and severity of illness • Two types of nutritional support • Enteral • Parenteral

21. What is enteral nutrition? • Enteral Nutrition • Also called "tube feeding," enteral nutrition is a liquid mixture of all the needed nutrients. • Consistency is sometimes similar to a milkshake. • It is given through a tube in the stomach or small intestine. • If oral feeding is not possible, or an extended NPO period is anticipated, an access devise for enteral feeding should be inserted at the time of surgery.

22. 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

23. 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

24. 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

25. 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?

26. 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

27. 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

28. Choosing Appropriate Formulas • Categories of enteral formulas: • Polymeric • Whole protein nitrogen source, for use in patients with normal or near normal GI function • Monomeric or elemental • Predigested nutrients; most have a low fat content or high % of MCT; for use in patients with severely impaired GI function • Disease specific • 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

29. Tulane Enteral Nutrition Product Formulary

30. 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 120 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 • Advance in increments of 20 mL q 8 hours to goal • Do not check gastric residuals

31. Aspiration Precautions • To prevent aspiration of tube feeding, keep HOB > 30° at all times • Use of blue dye to test for aspiration is controversial and has been discontinued in practice. • Discoloration • Falslely positive reading on guaiac tests • Reported deaths

32. Complications of Enteral Nutrition Support • Issues with access, administration, GI complications, metabolic complications. These include: • Nausea, vomitting, diarrhea, delayed gastric emptying, malabsorption, refeeding syndrome, hyponatremia, microbial contamination, tube obstruction, leakage from ostomy/stoma site, micronutrient deficiencies.

33. 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

34. Enteral Nutrition Case Study (continued) • Height: 5’4” IBW: 120# +/- 10% • Weight: 130# / 59kg 100% IBW • BMI: 22 • Usual weight: ~130# no weight change • Estimated needs: • 1475-1770 kcal (25-30 kcal/kg) • 59-71g protein (1-1.2 g/kg) • 1770 mL fluid (30 mL/kg)

35. 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

36. 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

37. What is parenteral nutrition? • 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.

38. 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

39. PPN vs. TPN • TPN (total parenteral nutrition) • High glucose concentration (15%-25% final dextrose concentration) • Provides a hyperosmolar formulation (1300-1800 mOsm/L) • Must be delivered into a large-diameter vein • 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

40. 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)

41. 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

42. Tulane Daily Parenteral Nutrition Order Form

43. 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 >250-400 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

44. 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 18-35 mg/dL • Adequate amino acids provided when there is an increase in pre-albumin of ~1 mg/dL per day

45. 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

46. 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 10-15 days • Limiting fat content of PN and cycling PN over 12 hours is needed to control steatosis in long-term PN patients

47. 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

48. 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

49. Parenteral Nutrition Case Study(continued) • Height: 6’0” IBW: 178# +/- 10% • Weight: 155# / 70kg 87% IBW • BMI: 21 • Usual wt: 175# 11% wt loss x 1 mo. • Estimated needs: • 2100-2450 kcal (30-35 kcal/kg) • 84-98g protein (1.2-1.4 g/kg) • 2100-2450 mL fluid (30-35 mL/kg)

50. Parenteral Nutrition Prescription • TPN via right-SC line • 2 L total volume x 24 hours • Amino acid 4.5% (or 45 g/liter) • Dextrose 17.5% (or 175 g/liter) • Lipid 20% 285 mL over 24 hours • Above will provide 2120 kcal, 90g protein, glucose infusion rate 3.5 mg/kg/minute, lipid 0.9 g/kg/day