For the Surgical Patient

Kelly Sparks LDN, RD

Lecture Outline

Energy SourcesNutrition RequirementsDiet AdvancementMicronutrients for wound healingEnteral versus Parenteral Nutrition

Case studies

Energy SourcesCarbohydrates

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 infectionsProtein

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

Nutrition Requirements

Healthy AdultsCalories: 25-35 kcals/kgProtein: 0.8-1 gm/kgFluids: 30 mls/kg

Requirement Change for the Surgical PatientSpecial Considerations

StressInjury or diseaseSurgery

Pre-hospital/pre-surgical nutrition

Nutrition

The surgical patient…Extraordinary stressors (hypovolemia,

hypervolemia, bacteremia, medications)Wound Healing

Anabolic state, appropriate vitamins (A, C, Zinc), and adequate kcals/protein.

Poor Nutrition=Poor OutcomesFor every gram deficit of untreated

hypoalbuminemia there is ~30% increase in mortality

Post-Operative Nutrition Requirements

Calories: Increase to 30-40 kcals/kgPatient on ventilator usually require less

calories ~20-25 kcal/kg

Protein:Increase to 1-1.8 grams/kg

Fluids: Individualized

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

Diet Advancement

Recent Evidence: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,)

Keep in Mind…

Per SLPWhen 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

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.

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.)

Key Nutrients for Wound Healing

Vitamin C:Collagen synthesisRDA=50-90 mg/dayLow 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.

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.

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 nutritionParenteral nutrition

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 syndromeFollowing severe trauma or burns

Contraindications to Enteral Nutrition Support

Malnourished patient expected to eat within 5-7 daysSevere acute pancreatitisHigh output enteric fistula distal to feeding tubeInability to gain accessIntractable vomiting or diarrheaAggressive therapy not warrantedExpected need less than 5-7 days if malnourished or

7-9 days if normally nourished

Enteral Access Devices

NasogastricNasoentericGastrostomy

PEG (percutaneous endoscopic gastrostomy)Surgical or open gastrostomy

JejunostomyPEJ (percutaneous endoscopic jejunostomy)Surgical or open jejunostomy

Transgastric JejunostomyPEG-J (percutaneous endoscopic gastro-jejunostomy)Surgical or open gastro-jejunostomy

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?

Gastric vs. Small Bowel Access

“If the stomach empties, use it.”

Indications to consider small bowel access:Gastroparesis / gastric ileusRecent abdominal surgerySepsisSignificant gastroesophageal refluxPancreatitisAspirationIleusProximal enteric fistula or obstruction

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

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

statesFormulas are available for respiratory disease, diabetes, renal

failure, hepatic failure, and immune compromise *well-designed clinical trials may or may not be available

Enteral Nutrition Prescription GuidelinesGastric feeding

Continuous feeding:Start at rate 30 mL/hourAdvance in increments of 20 mL q 8 hours to goalCheck gastric residuals q 4 hours

Bolus feeding:Start with 100-120 mL bolusIncrease by 60 mL q bolus to goal volumeTypical bolus frequency every 3-8 hours

Small bowel feedingContinuous feeding only; do not bolus due to risk of dumping

syndromeStart at rate 20 mL/hourAdvance in increments of 20 mL q 8 hours to goalDo not check gastric residuals

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

Complications of Enteral Nutrition Support

Nausea and vomiting / delayed gastric emptying

MalabsorptionCommon manifestations include unexplained weight

loss, steatorrhea, diarrheaPotential causes include gluten sensitive

enteropathy, Crohn’s disease, radiation enteritis, HIV/AIDS-related enteropathy, pancreatic insufficiency, short gut syndrome

Enteral Nutrition Case Study

78-year-old woman admitted with new CVASignificant 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 accessPlan of care is to stabilize the patient and transfer her

to a long-term care facility for rehabilitation

Enteral Nutrition Case Study (continued)

Height: 5’4” IBW: 120# +/- 10%Weight: 130# / 59kg 100% IBWBMI: 22Usual weight: ~130# no weight changeEstimated needs:

1475-1770 kcal (25-30 kcal/kg)59-71g protein (1-1.2 g/kg)1770 mL fluid (30 mL/kg)

Steps to determine the Enteral Nutrition Prescription

1. Estimate energy, protein, and fluid needs

2. Select most appropriate enteral formula

3. Determine continuous vs. bolus feeding

4. Determine goal rate to meet estimated needs

5. Write/recommend the enteral nutrition prescription

Enteral Nutrition Prescription

Tube feeding via PEG with full strength Jevity 1.2Initiate 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

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.

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 presentParalytic ileus, mesenteric ischemia, small bowel

obstruction, enteric fistula distal to enteral access sites

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 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 veinBecause of lower concentration, large fluid volumes are

needed to provide a comparable calorie and protein dose as TPN

Parenteral Access Devices

Peripheral venous accessCatheter placed percutaneously into a peripheral

vessel

Central venous access (catheter tip in SVC)Percutaneous jugular, femoral, or subclavian

catheterImplanted ports (surgically placed)PICC (peripherally inserted central catheter)

Writing TPN prescriptions

1. Determine total volume of formulation based on individual patient fluid needs

2. Determine amino acid (protein) contentAdequate to meet patient’s estimated needs

3. Determine dextrose (carbohydrate) content~70-80% of non-protein calories

4. Determine lipid (fat) content~20-30% non-protein calories

5. Determine electrolyte needs6. Determine acid/base status7. Check to make sure desired formulation will fit in the total

volume indicated

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

Parenteral Nutrition Monitoring (continued)

Check LFT’s weeklyIf 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 weeklyAdjust amino acid content of TPN/PPN to reach normal pre-

albumin 18-35 mg/dLAdequate amino acids provided when there is an increase in

pre-albumin of ~1 mg/dL per day

Parenteral Nutrition Monitoring(continued)

Acid/base balanceAdjust TPN/PPN anion concentration to maintain

proper acid/base balanceIncrease/decrease chloride content as neededSince bicarbonate is unstable in TPN/PPN

preparations, the precursor—acetate—is used; adjust acetate content as needed

Complications of Parenteral Nutrition

Hepatic steatosisMay occur within 1-2 weeks after starting PNMay be associated with fatty liver infiltrationUsually 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

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 cholestasisGastrointestinal 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

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 admitRight subclavian central line was placed and

plan noted to start TPN since patient is expected to be NPO for at least 1-2 weeks

Parenteral Nutrition Case Study(continued)

Height: 6’0” IBW: 178# +/- 10%Weight: 155# / 70kg 87% IBW BMI: 21Usual 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)

Parenteral Nutrition Prescription

TPN via right-SC line2200 mL total volume x 24 hoursAmino acid: 45 g/liter=

45g x 2.2 L= 99 grams x 4 kcals/gram =369 kcalsDextrose 175 g/liter=

175g x 2.2 L= 385 grams x 3.4 kcals/gram= 1309 kcalsLipid 20% 285 mL over 24 hours

285 mls x 2= 570 kcalsAbove will provide 2275 kcal, 99g protein, DIR=(385 g dex/ 70 kg /1440 minute in a day)*1000=

3.8mg/kg/minLIR= (285 mls lipid * 20%)/ 70 kg=0.8 g/kg/day

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. Propofol @ 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

Benefits of Enteral NutritionOver 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 infectionEnteral feeding—very small risk of infection and may

prevent bacterial translocation across the gut wall TPN—high risk/incidence of infection and sepsis

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 arrestWeakness, paralysisRespiratory depressionKetoacidosis / metabolic acidosis

Refeeding Syndrome (continued)

Prevention and TherapyCorrect electrolyte abnormalities before starting

nutrition supportContinue to monitor serum electrolytes after nutrition

support begins and replete aggressivelyInitiate nutrition support at low rate/concentration

(~ 50% of estimated needs) and advance to goal slowly in patients who are at high risk

Consequences of Over-feeding

Risks associated with over-feeding:HyperglycemiaHepatic dysfunction from fatty infiltrationRespiratory acidosis from increased CO2 productionDifficulty weaning from the ventilator

Risks associated with under-feeding:Depressed ventilatory driveDecreased respiratory muscle functionImpaired immune functionIncreased infection

Questions

Reference: American Society for Parenteral and Enteral Nutrition. The Science and Practice of Nutrition

Support. 2001. 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):1578-82

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. 1995 July;222(1):73-7.

Ross, R. Micronutrient recommendations for wound healing. Support Line. 2004(4): 4.