NUTRITION IN SURGICAL PATIENTS

ENTERAL VIS A VIS PARENTERAL NUTRITION

DR.BARUN KUMAR

UNIT IIA, GENERAL SURGERY

AT A GLANCE

• Basic principles guiding nutrition in surgical patients

• Enteral nutrition

• Parenteral nutrition

• Immuno nutrition

GOAL OF NUTRITIONAL SUPPORT

• PREVENT OR REVERSE THE CATABOLIC EFFEECT OF DISEASE OR INJURY

• TO MEET THE ENERGY REQUIREMENTS OF METABOLIC PROCESS

• TO MAINTAIN A NORMAL CORE BODY TEMPERATURE

• TO PROVIDE SUBSTRATES FOR ADEQUATE TISSUE REPAIR

ESTIMATION OF ENERGY REQUIREMENT

• ASSESSMENT OF PRE SURGERY NUTRITIONAL STATUS-

A] HISTORY, PHYSICAL EXAMINATION, BODY WEIGHT, BMI

B] BIOCHEMICAL TESTS: CREATININE EXCRETION, ALBUMIN , TOTAL COUNT, SERUM TRANSFERRIN

EVALUATING CALORIC REQUIREMENT:

Calculating resting Energy Expenditure (REE)

• Harris-Benedict Equation– Variables

gender, weight (kg), height (cm), age (years)

Men:66.47 + (13.75 x weight) + (5 x height) – (6.76 x age)

Women:65.51 + (9.56 x weight) + (1.85 x height) – (4.67 x age)

Calorie requirement = BEE x Activity factor x Stress factor

EVALUATING CALORIC REQUIREMENT:

• INDIRECT CALORIMETRY:

REE (kcal/day)= 1.44(3.9 Vo2 (ml/min) + 1.1 Vco2 )

• DUAL ENERGY X-RAY ABSORPTIOMETRY:

measure lean body mass, fat mass, bone density

Electrolyte requirements

• Na+ : 100-120 meq/day

• K+ : 80 – 120 meq/day

• Mg+ : 12 – 15 mmol/day

• Ca+ : around 5 mg/day

• Phosphorus : 14 – 16 mmol/day

Micro Nutrients

Agent Requirement/day

Iron 0 – 2 mg

Zinc 1 – 15 g

Copper 1 -5 g

Chromium 10 – 20 g

Selenium 20 – 100 g

Manganese 150 -800 mg

Vit E 10 – 50 IU

Vit A 2500 IU

Vit C 300 – 500 mg

Vit D 250 IU

Agent Requirement/day

Vit K 10 mg/week

Thiamine 50 – 250 mg

Riboflavin 5 mg

Niacin 50 mg

Pantothenate 15 mg

Pyridoxine 5 mg

Folic acid 600 g

BIZ 12g

Biotin 60g

PRINCIPLES GUIDING NUTRITION

• Use the oral route if the GI tract is fully functional and there are no other contraindications to oral feeding.

• Initiate nutrition via the enteral route if the patient is not expected to be on a full oral diet within 7 days post surgery and there are no GI tract contraindications

• If the enteral route is contraindicated or not tolerated, use the parenteral route within 24 to 48 hours in patients who are not expected to be able to tolerate full enteral nutrition (EN) within 7 days.

• Administer at least 20% of the caloric and protein requirements enterally while reaching the required goal with additional PN.

• Maintain PN until the patient is able to tolerate 75% of calories through the enteral route and EN until the patient is able to tolerate 75% of calories via the oral route

Contraindications to Enteral Nutrition

Intractable vomiting, diarrhea refractory to medical managementParalytic ileusDistal high-output intestinal fistulas (too distal to bypass with feeding tube)GI obstruction, ischemiaDiffuse peritonitisSevere shock or hemodynamically instabilitySevere GI hemorrhageSevere short bowel syndrome (less than 100 cm of small bowel remaining)Severe GI malabsorption (e.g., enteral nutrition failed, as evidenced by progressive deterioration in nutritional status)Inability to gain access to GI tractNeed is expected for <7 days

ENTERAL NUTRITION

• ROUTES OF ADMINISTRATION :

1. NASOGASTRIC

2. NASODUODENAL

3. NASOJEJUNAL

4. GASTROSTOMY-percutaneous, endoscopic, radiologic

5. JEJUNOSTOMY-percutaneous, endoscopic, radiologic

PATIENT MUST BE HEMODYNAMICALLY STABLE BEFORE STARTING ENETERAL NUTRITION

THE CONTRAINDICATIONS OF ENTERAL NUTRITION AS STATED EARLIER MUST BE RULED OUT.

THE CHOICE OF ROUTE MUST BE MADE, THE LEAST INVASIVE ONES ARE PREFFERED

NASOENTERIC:PATIENTS WITH INTACT MENTATION AND PROTECTIVE LARYNGEAL REFLEXES HEAD END OF THE BED RAISED TO 35 DEGREESRESIDUAL VOLUMES SHOULD BE CHECKED 1 HOUR AFTER MEAL AND IT SHOULD NOT EXCEED 50ML/HR SIGNS OF INTOLERANCE SHOULD BE MONITORED AND RATE AND OSMOLARITY ADJUSTED ACCORDINGLY.

ENTERAL NUTRITION

Gastric feeding Jejunal feeding

Solution usedHypertonic or

isotonicIsotonic

Infusion rateBolus or

continuousContinuous

Initiation of

infusion25-30mL/hr

Increments 25-30 mL/hr daily

Intolerance VomitingDistention, diarrhea,

colic, reflux to NGT

Enteral formulas:

1. Low residue isotonic formulas:

• Calorie density of 1 kcal/ml

• Non protein-calorie:nitrogen ratio =150:1

• No fibre, no bulk, no residue

• Cheap, first line for stable gi tract

2.Isotonic formula with fibre :

• Soluble and insoluble fibre

• Stimulate pancreatic lipase activity

• Degradation into short chain fatty acids

Enteral formulas: (cont)

3. Immune enhancing formulas: Glutamine, arginine, omega-3 fatty acids, nucleotides, beta

carotene

4. Calorie dense formula: 2kcal/ml5.High protein formula6.Elemental formula:• predigested nutrients, • Adv: ease of absorption in gut impairment, pancreatitis, • Disadv: poor in fat, vitamin, trace elements• High osmolarity, high cost7. Special formulas: renal/pulmonary/hepatic failure

patients

Advantages of enteral nutrition

• Provides the advantage of trophic feeding

• Maintain structural and functional support of intestinal mucosa by providing glutamine, preserving blood supply and promoting peristalsis

• Maintain integrity of int mucosa- prevents bacterial translocation

• Cheap, easy to administer, safe.

PARAMETER ACUTE PATIENT STABLE PATIENT

Electrolytes Daily 1-2×/week

Complete blood count Daily 1-2×/week

Glucose level3×/day; more often if poor

control

3×/day; less often if good

control

Creatinine and urea levels Daily Weekly or twice weekly

Nitrogen balance Daily 2-3×/week

Input and output Daily 2-3×/week

Body weight Daily 2-3×/week

Urine output Hourly every 4 hours

Stool Per motion Daily

Monitoring schedule for enteral feeding

Complications :

• Local problems: epistaxis, sinustis, nasal necrosis• Mechanical problems: tube malpositioning,

dislodgement• Gastroparesis: vomiting, aspiration

• REFEEDING SYNDROME: after prolonged fasting period leads to sudden rise in insulin and electrolyte abnormailities resp, hepatic and renal dysfunctionrate of feeding should be slow at starting

•Solute overload: Diarrhoea, dehydration, electrolyte disturbance, hyperglycemia,Loss of trace elementsIn severe cases, pneumatosis intestinalis with bowel necrosis and perforation

PROBLEM COMMON CAUSES MANAGEMENT

Diarrhea

Medications (e.g., antibiotics,

H2blockers, laxatives, hyperosmotic,

hypertonic solutions), feeding

intolerance (osmolarity, fat),

acquired lactase deficiency

1.Measure stool output.

2.Rule out infection

(bacterial, viral, parasitic).

3.Supply fibre.

4.Change medication or

formula.

5.Check osmolarity and

infusion rate.

6.Administer antimotility

medications (e.g.,

loperamide, codeine).

Nausea and

vomiting

Delayed stomach emptying,

constipation, abdominal distention,

odor and appearance of

formulations

1.Administer feedings at

room temperature.

2.Use isotonic formulations.

3.Use a closed system when

possible.

4.Reduce doses of

narcotics.

5.Use gastroprokinetic

agents (metoclopramide).

6.Monitor gastric residuals

and stool output.

Constipation,

fecal impactionDehydration, lack or excess of fibre

1.Monitor fluid balance daily.

2.Carry out rectal

disimpaction.

3.Consider the use of

cathartics, stool softeners,

laxatives, or enemas.

Aspiration

pneumonitis

Long-term supine position, delayed

stomach emptying, altered mental

status, malpositioned feeding tube,

vomiting

1.Place head of bed at 45

degrees during feedings.

2.Stop EN if gastric residual

volume exceeds 200 mL.

3.Use nasoduodenal or

nasojejunal tubes in patients

at risk.

Hyponatremia,

overhydration

Excess fluid intake, refeeding syndrome,

organ failure (e.g., liver, heart, kidney)

1.Monitor fluid balance and

body weight daily.

2.Consider fluid restriction.

3.Change formula (avoid low-

sodium intake).

4.Initiate diuretic therapy

HypernatremiaDehydration, inadequate fluid

intake 1.Increase free water.

Dehydration Diarrhea, inadequate fluid intake 1.Determine cause.

2.Increase fluid intake.

HyperglycemiaHigh content of carbohydrate in

feedings, insulin resistance

1.Evaluate and adjust

feeding formula.

2.Consider insulin

regimen.

Hypokalemia,

hypomagnesemia,

hypophosphatemia

Diarrhea, refeeding syndrome

1.Correct electrolyte

abnormalities.

2.Determine cause.

3.Reduce rate if refeeding

syndrome is present and

monitor patient.

HyperkalemiaExcess potassium intake, renal

impairment

1.Change feeding formula.

2.Reduce potassium

intake.

3.Consider insulin

regimen.

TOTAL PARENTERAL NUTRITION

• IV INFUSION OF NUTRIENTS IN ELEMENTAL FORM

• THE HIGH COST AND COMPLICATIONS HAS LIMITED ITS USE FOR PATIENTS IN WHICH CONTRAINDICATIONS TO ENTERAL FEEDING ARE PRESENT

• PATIENT MUST BE HEMODYNAMICALLY STABLE BEFORE ITS USE

CONDITIONS REQUIRING CAREFUL USE OF TPN

CONDITION SUGGESTED CRITERIA

Hyperglycemia Glucose >300 mg/dL

Azotemia BUN >100 mg/dL

Hyperosmolality Serum osmolality >350 mOsm/kg

Hypernatremia Na >150 mEq/L

Hypokalemia K <3 mEq/L

Hyperchloremic metabolic acidosis Cl >115 mEq/L

Hypophosphatemia Phosphorus <2 mg/dL

Hypochloremic metabolic alkalosis Cl <85 mEq/L

FORMULATIONS

• 2IN 1 SOLUTION : 60-70% DEXTROSE

10-20% AMINO ACIDS

• 3 IN 1 SOLUTION : IN ADDITION HAS 10-30% LIPID EMULSIONS

• IN ADDITION – STERILE WATER, ELECTROLYTE, MINERAL AND VITAMINS

CARBOHYDRATE CONTENT•dextrose•provide 3.4kcal/kg•Concentrated hypertonic solutions given via central line•Contraindications – alcohal withdrawal dehydrated patient, suspected ntracranial hemorrhage•Sufficient carbohydrate prevents glycogen breakdown, protein sparing effect•Suggested guideline of 25% dextrose at a rate of 7mg/kg/min

LIPID CONTENT•Dense source of energy 9kcal/gm•Prevents essential fatty acid deficiency•Soyabean oil(Omega-6 fatty acids) (linoleic acid) : pro inflammatory potential•Fish oil (omega-3 fatty acids) (eicosapentaenoic acid): lacks pro-inflammatory potential

PROTEIN CONTENT:•RDA = 0.8G/KG/DAY•20% of total energy requirements must be met by protein•Fasted surgical patients – 1.5 to 2 gm protein/kg/day•Severely injured patients – 3g/kg/day•Nitrogen to calorie ratio (1:150) •Low protein preparations in renal and hepatic failure

FLUID AND ELECTROLYTES:•Fluid : 30 to 40ml/ kg •Sod and pot- 1to 2 mEq/kg•Calcium- 10 to 15 mEq/kg•Magnesium- 8 to 20 mEq/kg•Phosphate- 20 to 40 mmol

COMPLICATIONS OF TPN

A.TECHNICAL PROBLEMS:

• Sepsis sec to contamination of the central venous catheter

earliest sign may be glucose intolerance

Fever without any other septic focus for more than 48 hours removal of catheter and reintroduction at new site

• Pneumo/hydro/hemothorax

• Cardiac arrhythmias, cardiac tamponade

• Air embolism, thoracic duct injury

COMPLICATIONS OF TPN(cont)

B.METABOLIC COMPLICATIONS:

• HYPERGLYCEMIA

• ELECTROLYTE ABNORMALITY

• OVERFEEDING – co2 retention and repiratory insufficiency, hepatic steatosis,

• Cholestasis and gall stones

• Raised liver enzymes

C.INTESTINAL ATROPHY

IMMUNO NUTRITION

• Nutrients affecting the immune system

• Recognised: arginine, glutamine, omega-3 fatty acids, nucleotides

• Potential : vit c and e, selenium copper zinc,

taurine, branched chain amino acids, n acetyl-cysteine

ARGININE• Semi essential amino acid• Relative deficiency in metabolic stress• Metabolic role : a. collagen synthesis

b.secretagouge for insulin, prolactin, growth harmone

c.nitric oxide donor• Counteract myeloid suppressor cells alongwith omega-3

fatty acids• Zeta chain in t cell receptor complex is arginine sensitive• Evidence based role in patients following burns• Pro inflammatory role: might be counterproductive in

sepsis• Dosage : 12gm/1000 calorie

GLUTAMINE

• Semi essential amino acid• Fuel for enterocyte , colonocyte, lymphocyte• Component of glutathione, • precursor of nucleotide synthesis, neoglucogenesis• Synthesis of mucin protecting gut mucosa• Downregulate toll-like receptor, reduce inflammatory

cytokines• Proven benefit in post-burn• Early studies shows beneficial effects in critically ill patients• Unstable in solution – packed in dipeptide form,

powder/granule form• Dosage: eneteral- 3.5gm/100 gm of protein• parenteral- 0.285 to 0.4 g/kg/day

OMEGA-3 FATTY ACIDS• ALPHA-LINOLEIC ACID, EICOSAPENTANOIC ACID,

DOCOSAHEXAENOIC ACID

• As discussed earlier omega-6 FA has pro and omega-3 FA has anti inflammatory effects

• Anti-inflammatory effects of O3FAi. Displaces arachadonic acid from memb phospholipidsii. Inhibits conversion of linoleic to arachdonic acidiii. Activates peroxisomal receptorsiv. Stabilise nf-kb, suppress pro-inflammatory genesv. Reduce expression of icam-1 & E-SELECTINS• Stabilise myocardium, reduce arrhythmia• Reduced risk of ards

NUCLEOTIDES

• Essential for dna and rna synthesis

• Proliferation and normal functioning of phagocytes

• Protects guts from mucosal atrophy

• Most standard enteral and parenteral formulas lacks nucleotides

TAKE HOME MESSAGE

• The role of nutrition in surgical patients with increased metabolic demands cannot be over-emphasized

• A clear understanding of body’s energy, fluid, electrolytes and micro nutrients is essential

• Whenever the gut is available for use, USE IT!!!!

• Parenteral nutrition should be reserved for the patients in whom a clear contraindication to enteral nutrition is present

•Even with parenteral nutrition, 20% of the total energy requirement should be tried to meet with enteral nutrition for the trophic effect on gut •A careful watch for possible complications should be kept on patients receiving both enteral and parenteral nutrition• overfeeding should be avoided for its dangerous complications in critically ill patients

•The role of immuno nutrients are still under study and till then, its use can be reserved for the patients in which proven efficacy has been shown in studies.

Thank you