Nutrition in Burns in the human for medication

nutritiuon burn in the human

1. Nutrition in Burns

2. Contents Introduction Metabolic pathology Macronutrient requirements Micronutrient requirements Modes of nutrition Enteral Parenteral Nutritional assessment and monitoring

3. Introduction In burns, overwhelming metabolic response to thermal injury (2 x normal metabolism) compromises wound healing capacity, muscle wasting , organ dysfunction, increased susceptibility to infection. Burns > 20% TBSA – Massive metabolic injury Massive burns represent a metabolic “double hit” – Increased demand for anabolic mechanism for wound healing simultaneously triggering a systemic catabolic state. Resulting mismatch (demand and supply)

4. Three important things to understand- Burn injury-most pronounced catabolism of any clinical condition >25gm/day (150gm protein or ½ pound/225gm lean bodymass ‘crescendo–decrescendo’ nature of this process: nitrogen excretion rises immediately, reach a maximum at 7–14 days postburn and declines gradually. Impossibility of using static formulas to estimate nutritional requirements

5. RESPONSE OF BODY TO STRESS burn trauma  increases in the catabolic hormones [H] epinephrine, cortisol and glucagon  accelerated gluconeogenesis, glycogenolysis and muscle proteolysis. Catabolic “H” counteract effect of insulin/GH  blood sugar levels rise and protein synthesis and lipogenesis are inhibited.

6. HOW IS BURNS INJURY DIFFERENT? In BURNS - skeletal muscle  obligatory fuel for hypermetabolism. In starvation  Metabolic rate falls, lipolysis and ketosis provide energy and protect muscle reserves. Burn injury  reduces the body’s ability to utilize fat as an energy source. Hence, Lipids have limited protein-sparing effect. A diet composed largely of carbohydrates is required to reduce protein catabolism. (Glucose-limited protein sparing)

7. Introduction Increased Demand for amino acids for tissue repair Acute phase protein production Cellular immunity Gluconeogenesis 40% loss in body wt or loss of 1/3 rd protein is associated with mortality 20% weight loss – poor wound healing 10% weight loss – acceptable To accommodate to these – Increased amino acid efflux from the skeletal muscles DIMINISHED LEAN BODY MASS

8. WHAT HAS CHANGED IN MODERN BURN CARE? Maintaining ambient temperature (37-39 ºC and relative humidity - caloric requirements by 20% ⬇︎⬇︎⬇︎ Antibiotics and routine early burn wound excision have reduced infection. Covering burn wounds  shortens the duration of hypermetabolism. Other therapies, including mechanical ventilation and chemical sedation/paralysis, also reduce energy requirements

9. Metabolic pathology

10. Metabolic pathology associated with burn injury

11. Metabolic pathology EBB PHASE – 12-24 hrs BP, CO, Temperature, O2 consumption – Reduced Increased capillary permeability and loss of skin cover Capillary fluid shift – Hypotension, Haemoconcentration, Reduced urine output Cellular dehydration Loss of water and electrolytes (mainly Na) and proteins Body water shifts from ECF in other parts to burn site – further loss from site

12. Metabolic pathology FLOW PHASE – After 48-72 hrs Fluid and electrolytes are reabsorbed, excess fluid is excreted Metabolism is maximum – day 5 to day 12 - Raised substrate utilisation Increased heat elimination Weight loss More blood flow to burn wound to provide more glucose for healing Major heat loss via evaporation Wound evaporative losses = TBSA x (25 + % of BSA burned) (ml/hour) 165cm, 65kg – 1.73 m 2

13. Metabolic pathology ANABOLIC PHASE – Patient is well hydrated Metabolic reactions are under control Important for Fast recovery and rehabilitation

14. MACRONUTRIENT requirement CARBOHYDRATES – On one hand – failure to provide adequate carbs results in additional compensatory protein catabolism On the other hand – limited capacity of glucose oxidation Carbs in excess of patients capacity – hypergylcemia , glucosuria , hypertriglyceridemia 4 Kcal/gm 5g/kg/day in adult 7g/kg/day in children More than this leads to hyperglycemia with resultant lactic acidosis

15. EXCESS FEEDING? Attempting to ‘catch up’ by providing excess calories or protein is ineffective Leads to hyperglycaemia, CO2 retention, and azotaemia Therefore, the primary goal of nutritional support in burn patients is to satisfy ongoing requirements.

16. MACRONUTRIENT requirement FATS – Critical to effective homeostasis and wound healing Hypermetabolic response to thermal trauma upregulates lipolysis Countered by increased hepatic esterification - RISK OF HEPATIC STEATOSIS 9Kcal/gm 15% of total calories

17. MACRONUTRIENT requirement PROTEIN – Proteolysis is the metabolic hallmark of hypermetabolic response to burn injury ~150g of skeletal muscle is lost per day in absence of nutritional support 1.5-2 g/kg/day in burned adults 2.5-4 g/kg/day in burned children BUT, increasing above these values – urea load and azotemia Amino acids – Alanine, arginine, glutamine – key role in wound healing GLUTAMINE – important role in function of enterocytes and lymphocytes Increased bowel permeability Infection

18. Micronutrient requirement MICRONUTRIENT FUNCTION SOURCES VIT A GLYCOPROTEIN AND COLLAGEN SYNTHESIS FISH OIL , EGG YOLK , DAIRY PRODUCTS VIT E ANTIOXIDANT PROPERTIES NUTS, LEGUMES, GREEN LEAFY VEGETABLES VIT K COAGULATION GREEN LEAFY VEGETABLES, DAIRY , MEAT , EGG VIT C ( ASCORBIC ACID) HYDROXYLATION OF LYSINE , PROLINE- COLLAGEN FORMATION AND CROSS LINKING PROTECTS TISSUE FROM SUPEROXIDE DAMAGE ENHANCES TISSUE REGENERATION CITRUS FRUITS, GREEN VEGETABLES

19. Micronutrient requirement MICRONUTRIENT FUNCTION SOURCES VIT B1 (THIAMINE) COLLAGEN CROSS LINKING LEGUMES, NUTS, MEAT,PORK VIT B2 (RIBOFLAVIN) COLLAGEN CROSS LINKING BROCCOLI, SPINACH, MEAT, POULTRY , FISH VIT B6 (PYRIDOXINE) COENZYME THAT ACTIVATES PROTEIN SYNTHESIS CHICKEN , FISH , EGGS, PORK VIT B 12 (COBALAMINE) COENZYME THAT ACTIVATES PROTEIN SYNTHESIS MEAT , POULTRY , FISH , EGGS

20. Micronutrient requirement MICRONUTRIENT FUNCTION SOURCES MAGNESIUM COFACTOR – PROTEIN AND COLLAGEN SYNTHESIS NUTS, LEGUMES, GREEN VEGETABLES CALCIUM COLLAGENASES-COLLAGEN REMODELLING DAIRY PRODUCTS, GREENS COPPER CROSS LINKING OF COLLAGEN, ELASTIN SCAVENGES FREE RADICALS CEREALS, MEAT,POULTRY IRON HYDROXYLATION OF PROLINE , LYSINE- IN COLLAGEN SYNTHESIS EGG YOLK, GREENS,RED MEAT, LEGUMES SELENIUM REDUCE INTRACELLULAR HYDROPEROXIDE SEAFOOD , GRAINS ZINC COFACTOR – PROMOTES PROTEIN SYNTHESIS , COLLAGEN FORMATION MEAT, PORK

21. Micronutrient guidelines Mayes I,Gottschlich MM,Warden GO.Clinical nutrition protocols for continuous quality improvements in the outcomes of patients with burns. J Burn Care Rehabil 1997;18:365-368 ADULTS AND CHILDREN CHILDREN >3 YRS < 3 YRS >20 % TBSA >10%TBSA 1 MVT OD 1 CHILDRENS MVT OD 500 MG ASCORBIC ACID BD 250 MG ASCORBIC ACID BD 10,000 IU VIT A OD 5000 IU VIT A OD 220 MG ZINC SULPHATE OD 110 MG ZINC SULPHATE OD

22. Nutritional support

23. TIME to start nutrition Early enteral nutrition is preferred (<6 hrs after injury) EARLY INITIATION Improved survival and function of enteric mucosa and decreased bacterial translocation Significantly blunts the catabolic response Hemodynamic instability – avoid full feeds & Increase gradually. Careful if on vasopressors – risk of mesenteric ischemia/gastric ileus Stable patients – initiate rapidly Start with hypocaloric mixture (0.5Kcal/ml) @25ml/hr Increase by 25 ml every 8 hours to 100-120 ml/hr

24. Enteral nutrition ADVANTAGES - Supports the alimentary tract Direct high concentration nutrients like glutamine and alanine Stimulate enteric blood flow Maintain barrier function by preserving tight junction integrity Polysaccharides by this route undergo bacterial fermentation – Supports normal flora of the gut lumen

25. Delivering enteral feeds PO feeding – Preferred modality Calculate calorie and protein values Enteral access for feeding – NG tube / NJ tube / Percutaneous gastrostomy NG – risk of aspiration in immediate post burn phase NJ/NG tube feeding can be initiated within 6 hours following injury. Recent studies - Risk of pneumonia comparable in both NG/NJ tube

26. Delivering enteral feeds Small amount of low bulk feeds initially Small frequent feeds initially Gastric aspirate should be <150ml after 4 hours Start at 15 ml/ hr and gradually increase to 100 ml/ hr

27. Parenteral nutrition INDICATIONS – Patients unable to tolerate enteral feeds Supplement to enteral feeds in extensive burns GI dysfunction/Paralytic ileus Septic complications/Inhalational injury Patient on ventilator support

28. Parenteral nutrition 2-in-1 Solution – TPN without Lipid Calories from Dextrose – 75-80% Calories from Amino acids – 20-25% 3-in-1 Solution – TPN with Lipid Calories from dextrose – 55-60% Calories from amino acids – 20-25% Calories from lipids – 20% Separate components – Amino drip Intralipid 10% dextrose Premixed solution - Clinomel

29. Oliclinomel – All in one system 3 compartment bag 4 different preparations and volumes 1000ml 1500 ml 2000ml 2500 ml Lipid emulsion 200 ml 300ml 400 ml 500 ml Amino acid solution 400 ml 600 ml 800 ml 1000ml Glucose solution 400 ml 600 ml 800 ml 1000 ml Maximum daily dose – 40 ml/kg (2800ml for a 70 kg patient} Children – 100ml/kg

30. Complications of nutritional support Most common complication – Diarrhoea – multifactorial In the setting of shock – mucosal failure due to ischemia Medications (antacids and antibiotics) r/o clostridium difficile Most common source – feed themselves – High osmolar concentration High volume Gut response to stress Aggressive hyperosmolar solute – pneumatosis intestinalis and bowel perforation State of relative solute overload

31. Complications of enteral feeds Problem Common causes Management Aspiration pneumonitis Long-term supine position, delayed stomach emptying, altered mental status, malpositioned feeding tube, Place head of bed at 45 degrees during feedings Stop EN if gastric residual volume exceeds 200 mL Hypervolemic hyponatremia ( overhydration ) Excess fluid intake, refeeding syndrome, organ failure (e.g., liver, heart, kidney) Monitor fluid balance and body weight daily Consider fluid restriction Change formula (avoid low-sodium intake) Initiate diuretic therapy

32. Complications of enteral feeds Problem Common causes Management Hypernatremia Dehydration, inadequate fluid intake Increase free water Dehydration Diarrhea , inadequate fluid intake Determine cause Increase fluid intake Hyperglycemia High content of carbohydrate in feedings, insulin resistance Evaluate and adjust feeding formula Consider insulin regimen Check for dextrose-based carriers in IV medications Hypokalemia , hypomagnesemia , hypophosphatemia Diarrhea , refeeding syndrome Correct electrolyte abnormalities Determine cause Reduce rate if refeeding syndrome is present and monitor patient Hyperkalemia Excess potassium intake, renal impairment Change feeding formula Reduce potassium intake Consider insulin regimen

33. Complications of parenteral nutrition Problem Common causes Management Hypoglycemia Excess insulin administration, sudden cessation of PN infusion Stop insulin Start 10% dextrose IV Give a 50% dextrose ampule before resuming central line feeding Hyperglycemia Excess dextrose concentration, stressassociated (e.g., sepsis), chromium deficiency 0.1–0.2 U insulin/g dextrose therapy, SQ or IV insulin sliding scale, limit dextrose content, consider discontinuing PN until improved blood glucose control Hypertriglyceridemia (acceptable concentrations <400 mg/ dL ) Dextrose overfeeding, rapid administration of intravenous fatty emulsion (>110 mg/kg/h) Infusion of IVFE should be restricted to less than 30% of total calories or 1 g/kg/day, given slowly, over no less than 8 to 10 h, if administered separately

34. Complications of parenteral nutrition Problem Common causes Management Essential fatty acid deficiency (e.g., dermatitis, alopecia, hepatomegaly, thrombocytopenia, anemia ) 1- to 3-week administration of PN lacking linoleic and alpha- linolenic fatty acid emulsions 2–4% daily energy requirements should be derived from linoleic acid, 0.5% from alpha- linolenic acid43 (500 mL of 10% IVFE over 8–10 h, twice weekly) Electrolyte and mineral abnormalities Inadequate monitoring Inadequate supplementation in TPN formula Electrolytes should be checked daily and parenteral nutrition formulas should be adjusted daily until electrolytes stabilized Parenteral iron uncommonly increases risk of anaphylactic reactions

35. Complications of parenteral nutrition Problem Common causes Management Azotemia Dehydration, excess protein, inadequate carbohydrate calories Free water, 5% dextrose via a peripheral vein Metabolic bone disease (osteoporosis in 41% of those on long-term home PN) Unclear, multifactorial (e.g., postmenopausal, long-term PN, Cushing’s syndrome, Crohn’s disease, malabsorption , multiple myeloma, osteogenesis imperfect, corticosteroids, heparin, immobilization) Early screening of risk factors, DEXA, management of premorbid conditions Special PN considerations: Supplement calcium, P, Mg, Cu Minimize aluminum contamination, treat metabolic acidosis, avoid heparin Elevated liver function parameters (increased transaminase, bilirubin, alkaline phosphatase levels) Common following initiation; usually temporary If persistent, usually caused by amino acid load; reduce protein delivery

36. Complications of nutritional support REFEEDING SYNDROME – Dramatic clinical entity occasionally seen when initiating nutritional support in patients with long standing starvation Massive influx of electrolytes inside the cell Refractory hypokalemia , hypomagnesemia , hypophosphatemia May lead to cardiac failure and dysrhythmia, respiratory failure, neurological disturbances and renal and hepatic dysfunction. Give thiamine before starting PN (250mg in 100ml 5% dextrose)

37. Weaning of parenteral nutrition Slowly Monitor sugar levels IV Dextrose 10% at 100 ml/ hr for 4-6 hours

38. Peripheral line vs central line Peripheral line Convenient Low infection/complication rate For short term (<7 days) Supplementary nutrition Lack of expertise Central line Totally dependent on parenteral nutrition >7 days Using hyperosmolar liquids (avoid thrombophlebitis) Increased risk of infection and complication IDEAL – Subclavian – IJV – Femoral

39. Nutritional assessment and monitoring

40. Total caloric requirement CURRERI FORMULA Cal-calories( kcal/day) W- weight in kg BSAB- % TBSA burned AGE (YRS) FORMULA 16-59 Cal=(25 X W) + ( 40 X % BSAB) >60 Cal=(20 X W) + ( 65 X % BSAB)

41. Total caloric requirement Galveston formula BSA- Body surface area BSAB- % TBSA burned FORMULA AGE ( YEARS) EQUATION GALVESTON INFANT 0-1 2100 Kcal/ m² BSA + 1000 Kcal/ m² BSAB GALVESTON REVISED 1-11 1800 Kcal/ m² BSA + 1300 Kcal/ m² BSAB GALVESTON ADOLESCENT 12+ 1500 Kcal/ m² BSA + 1500 Kcal/ m² BSAB

42. Total caloric requirement INDIRECT CALORIMETRY – Gold standard Measures O2 consumption and CO2 production over period of time Used in Patients whose nutritional needs are difficult to assess Patients not responding to nutritional support appropriately Measured when patient is completely at rest. Actual daily energy expenditure is estimated by increasing the result by 10-20% to allow for variability and activity

43. Total caloric requirement REE (Resting energy expenditure) = 1.44 (3.9 VO2 [ml/min] + 1.1 VCO2 [ml/min]) (O2 consumption) (CO2 Production) Traditionally nitrogen balances have been used to assess the balance between protein anabolism and catabolism. But in burn patients large quantities of nitrogen lost in the wound exudate makes measurement of N balance difficult

44. Nutrition in special conditions PULMONARY COMPLICATION – Low carbs and high fat (30-50%) Increased glucose leads to more CO2 production. RENAL COMPLICATION – Protein restricted diet 0.6-1gm/kg/day initially and gradually increase Monitor BUN levels Patients have oliguria and hyperkalemia – Restrict citrus fruits and IVF with K + (RL) HEPATIC COMPLICATIONS – CLD – aromatic amino acids – hepatic encephalopathy Branched chain amino acids are preferred Milk and vegetable protein preferred over meat

45. Adjuvant therapy Hormonal therapy, Oxandrolone , Immunotherapy, Albumin

46. Recombinant growth hormone Potent anabolic agent Mechanism – (Mediated through IGF-1) Reduces hepatic acute phase response Maintains muscular growth Blunts hypermetabolism Decreases donor site healing time by approximately 1.5 days Augments nitrogen retention Dose – 0.5 IU/Kg/day for 2 weeks Side effects – Fluid retention, hyperglycaemia

47. Oxandrolone Testosterone analogue Dose – 0.1 mg/kg twice daily Suppresses cortisol action at cellular level Helps in wound healing Improves muscle protein anabolism

48. Immunotherapy Pentaglobin ( i.v. immunoglobins) Antibacterial, anti toxin, anti inflammatory, immune modulating

49. Stepwise calculations of nutritional requirements Step 1 – Energy – For eg 2050 Kcal (for 50kg and 20% burn) Step 2 – Protein requirement – 2 x wt = 100gm (100 x 4 = 400 Kcal) Non protein energy = 1650 – 400 = 1650 Kcal Step 3 – Half of non protein Kcal by Fat and carbs each Fat 20% on non protein calorie) – 330 Kcal (330/9 = 40Gm) Carbs – rest by carbs Step 4 – 1 Litre of 5% Dextrose = 50 gm of glucose monohydrate = 50 x 4 = 200 Kcal 6.25gm of protein = 1gm of body nitrogen

50. Stepwise calculations of nutritional requirements Step 5 – Calculate fluid intake in 24 hours – 40ml/kg/day = 40 x 50 = 2000ml/day Step 6 – Prepare standard nutrition for 2000ml 100gms protein = 1000 ml of 10% amino acids 150 gms of carbs = 750 ml of 20% dextrose 70gms of lipids = 350 ml of 20% lipofundin Total volume – 2100 ml giving 1650 calories

51. Stepwise calculations of nutritional requirements Step 7 – If patient has renal failure – reduce protein intake to 40gm/day and 1000 ml fluid/day 40gm of protein – 400 ml of 10% amino drip 150 gm of carbs = 300 ml of 50% dextrose 70gm of fat = 250 ml of 30% lipids Final volume = 950 ml giving 1470 calories

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