Strategies to Optimize Enteral Nutrition in the Critically Ill Patient. Patricia S. Anthony, MS, RD Gland, Switzerland

Transcription

1 Strategies to Optimize Enteral Nutrition in the Critically Ill Patient Patricia S. Anthony, MS, RD Gland, Switzerland

2 Goals of Nutrition Support Have Evolved : FROM: Adjunctive Care Preserve lean body mass Preserve immune function Minimize metabolic complications TO: Therapeutic Strategy Attenuate the disease /hypermetabolic response Maintain gut integrity Favorably modulate the immune response Minimize metabolic complications Preserve lean body mass Preserve immune function

3 What, When & Where to Feed the Critically ill Patient...

4 Feeding of ICU Patients Has Also Changed % ICU Days TPN Enteral Nutrition Support Trends in Surgical ICU over 10 Years (Berger 1997)

5 When the Gut works, Use it! Choices: TPN vs EN

6 TPN vs EN: Outcomes Meta-Analysis Gramlich L, et al. Nutr 2004; 20: RCTs included, all reported clinically important outcomes No Difference: Vent time or Hosp LOS PN had higher incidence of hyperglycemia 4 studies documented cost savings with EN

7 RR= 0.64; p=0.004 TPN vs EN: Infectious Complications Gramlich L, et al. Nutr 2004; 20:

8 RR= 1.08, no diff TPN vs EN Mortality Gramlich L, et al. Nutr 2004; 20:

9 Why is TPN vs EN? With TPN: Gut hormones are not stimulated GALT is adversely affected Gut bacteria are more virulent Relative Nutrient deficiencies (ex: no glutamine) Limitations in CHO, Fat, and Protein sources More metabolic derangements

10 Benefits of Enteral Nutrition Increases blood flow to the gut Maintains mucosal & gut integrity Better nutrient use with fewer metabolic disturbances & complications than TPN Promotes gut motility Supports the immune system More cost effective than TPN (Raper 1992; Jolliet 1998; Moore 1992)

11 Feeding Maintains GALT / MALT GALT MALT

12 Feeding Affects Immune Response CD 4 Helper T Cell Response Sets Environment Inflamatory Down Regulation Th1 Cellular Th2 Dendritic Macrophage Microbes Tolerance Th3 Humoral

13 Loss of Structural Integrity with Gut Disuse Controls Panc on ETF Panc on TPN Groos (J Submicro Cytol Path 1996;28:61)

14 Loss of Functional Integrity with Gut Disuse Intestinal Permeability PEG 3350(%) Retrieval p=0.002 R=0.08 Systemic Endotoxemia 2 TPN ETF IgM Antibody to Endotoxin % - 1.1% p< Windsor (GUT 1998;42:431) 2 Ammori (J Gastro Surg 1999;3:252)

15 Benefits of Early EN: Human Studies Less weight loss Improved nutrition indices Blunted hypermetabolism (burns) Decreased infections Improved wound healing Shorter LOS after GI surgery Shorter ICU stay after head injury Aggressive protein feeding improved survival in burn pts Improved survival after femur fx

16 Early EN Meta-analysis Marik and Zaloga. CCM 2001; 29: Infectious Complications RR= 0.43 EN vs Late EN No Diff in Mortality

17 Early EN Meta-analysis Marik and Zaloga. CCM 2001; 29: Reduction of ICU days by Mean of 2.2 days with Early EN

18 Does Early EN Really Work? Meta-analysis Author / journal Study parameters Study design Outcome of EEN Marik CCM 2001 Feeding < or > 36h 15 studies 753 patients infections LOS Lewis BMJ 2001 Heyland JPEN 2003 NPO vs <24h 11 studies 837 patients infections LOS vomiting risk < 24 to 48 h 8 studies Trend to infections & mortality

19 Is Early Feeding Safe? Early Post-Op Feeding Trials Author Year N Population Timing Success McDonald Burn 6h 85% McCarter UGI 24h 78% Heslin UGI CA 24h 80% Velez GI 6h 81% Hedberg Post-op 12h 85% Braga Post-op 12h 91% DiFronzo Colon (PO) 48h 97% James Whipple 24h 85%

20 Author Adams McClave Montejo Braga Woodcock DeJonge Kozar Enteral Tolerance in Critical Care Populations Journal YR Int Care Med 97 CCM 99 CCM 99 CCM 01 Nutr 01 CCM 01 J Surg Res 02 Approx % Reaching Goal 51% 52% 63% 80% 25% 86% 65-85%

21 Route of Enteral Nutrition 1. Oral 2. Gastric 3. Duodenal/Jejunal For patients that can t be fed adequately, or with high risk of gastroparesis or aspiration

22 Mechanics of Early Feeding Start slow 10 to 20 cc/h Advance only with tolerance Use full strength formula Attempt to reach goal by 96 hours Repeated unsuccessful attempts may require partial parenteral support

23 Clinical Evidence of Enteral Feeding Intolerance Distention Pain Nasogastric tube (NGT) output Diarrhea Pneumotosis Abdominal compartment syndrome NOTE: no mention of bowel sounds

24 Contraindications to Enteral Feeding Emesis Obstruction Upper GI bleed (major) Inability to access Hemodynamic instability Increasing pressor requirement MAP < 60 mmhg Base feeding decisions on clinical condition Not presence or absence of Bowel Sounds

25 Outcomes in Critically Ill Patients Before & After Implementation of an Evidence-Based Nutritional Management Protocol Prospective evaluation before & after evidence based protocol introduction N=200 Med-Surg ICU Conclusions: Increased delivery of nutrient Shortened duration of mechanical ventilation Decrease mortality Barr J et al Chest 2004: 125:

26 Gastric Residual Volume Interpretation Overt regurgitation / aspiration stop feeds GRV > 500cc Stop feed & assess patient GRV > 200cc - < 500cc Return aspirate to patient & perform careful evaluation of tolerance and risk. GRV < 200cc Return aspirate to patient and continue ongoing assessment of risk. North American Summit on Aspiration, JPEN 2002 (supp)

27 McClave et al CCM 2005,33:

28 Decreasing Risk of Aspiration Use of small bowel feedings below the ligament of Treitz (vs. just post-pyloric) Evaluation of sedation medication use Constant elevation of the bed > (even during transport) Use of continuous feeds Improved oral health Use of prokinetic agents,(i.e. metoclopramide/ erythomycin) Increased nursing to patient ratio Use of endo-tracheal tubes designed to provide continuous aspiration of subglottic secretions (CASS)

29 What is the Optimal Formula? NO single formula meets needs for all patients Consider the disease/condition in selection of nutrient solution Decision should depend upon: Metabolic insult Condition of the mucosa Severity of condition Expected duration of need Tolerance Base decision on scientific evaluation of the data

30 Nutrient Requirements for ICU Patients Energy: kcal/kg/day usual BW (non-obese) non-protein kcal/kg/day (non-obese) 21 kcal/kg/day BW (obese) Ventilated or paralyzed - energy requirement - 30% Lipid: Up to 30-35% total calories Minimum 2-4% as EFA Protein 15-20% total calories 1-2 g/kg/day Max: g/kg/day (extreme losses) Carbohydrate 4-7 mg/kg/minute g/day (70 kg pt) Reasonable glycemic control with insulin therapy 35-55% total calories (Jolliet 1998; Cresci & Martindale 2002; Lottenburg 2005; Ministry of Health, Malaysia 2005; ASPEN 2002, Bistrian 2005)

31 Type of Protein Just as Important as the Amount (Jolliet 1998; Tome 2001; Yoshizawa 2004)

32 Who is at Risk for Malabsorption? Metabolic, Physiologic & gut changes occur Even in a Normal Gut Puts critically ill and highly stressed patient at risk of malabsorption and gut atrophy Consider a peptide formula to maximize nutrient utilization

33 Peptide Advantage - Nitrogen Retention & Absorption (Zaloga 1992)

34 Whey

35 Whey Protein Optimizes Oxidative Defenses ICU patients have requirements for cysteine Reflects glutathione synthesis to fight oxidative stress Whey protein is rich in cysteine Precursor for glutathione (GSH) EN formula rich in cysteine helps meet requirements in hypercatabolic conditions Ensures adequate glutathione status To support immune function Fight free radicals & oxidative stress often seen in critical care patients (Breuille 1997)

36 Supplying Large Amounts of Carbohydrates Leads to Hyperglycemia Insulin resistance Impaired wound healing HYPERGLYCEMIA (Effects in stressed patients) Risk of infection Risk of loss LBM Skeletal muscle proteolysis Oxidative stress (proinflammatory)

37 Lipids Lipids - Important substrate for ICU patients: Provides energy and protein sparing Minimizes need for excessive carbohydrate load Caloric dense Provides essential fatty acids (EFA) Which lipid source? Risk for LCT fat malabsorption with compromised gut Use low inflammatory fats Omega 3 FA, MCT

38 Key nutrients: Vitamins and Trace Minerals in Critical Illness B vitamins Antioxidants (A,C, E, Se, Zn, Cu, Mn) No official guidelines available supplement any deficiency prevent deficiency Critical Illness: losses via wound, GI tract, urine requirements due to inflammatory response release of free radicals thus need for antioxidants

39 Is it really Diarrhea? No universally accepted definition Clinically useful definition: any abnormal volume or consistency of stool that results in fluid and electrolyte or acid/base imbalance Other definition: >500 ml every 8 hrs or >3 stools/day for at least 2 consecutive days Stool is usually pasty in pts fed non-fiber containing formulas

40 The cause of the Diarrhea is usually NOT the enteral feeding

41 Is it really Diarrhea? What is underlying diagnosis? malabsorption? malnutrition ( albumin level) was there diarrhea before the EN was started? Quantify stool volume Review medication list Is the most appropriate EN formula being used? Is enteral feeding being fed too fast? Check for infection (i.e. clostridium difficile, etc.) Consider bacterial overgrowth Consider use of fiber formula Consider use of anti-diarrheal agent Consider degree of malnutrition

42 Medications Common diarrhea culprits Antibiotics Sorbitol containing medications H 2 blockers Lactulose / laxatives Magnesium containing antacids Potassium & PO 4 supplements Antineoplastics Quinidine

43 Commonly Used Medications Osmolality Acetaminophen (65 mg/ml) Aminophylline liquid (21 mg/ml) Ampicillin suspension (50 mg/ml) Cimetidine solution ( 60 mg/ml) Digoxin elixir (50 mcg/ml) Ferrous sulfate liquid (60 mg/ml) Furosemide solution (10 mg/ml) Magnesium citrate solution Metaclopramide syrup (1 mg/ml) Multivitamin liquid 5400 mosm/kg 450 mosm/kg 2250 mosm/kg 5550 mosm/kg 1350 mosm/kg 4700 mosm/kg 2050 mosm/kg 1000 mosm/kg 8350 mosm/kg 5700 mosm/kg

44 Osmolality of Foods Milk Gelatin Broth Cola Popsicles Juices 275 mosm/l 535 mosm/l 445 mosm/l 750 mosm/l 720 mosm/l 990 mosm/l Ice Cream 1150 mosm/l

45 Safe Handling Techniques Formula hang time Mixing powdered formulas Sterile or boiled, cooled water used Clean blender and mixing utensils &containers Storage of unused open formula Frequency of bag change Frequent hand washing

46 Formula Hang Time Hang only 4-6 hours of formula at one time Do not add new formula to existing formula in bag Hang less formula in warm environments

47 Formula Storage Store open formula in a covered container in the refrigerator Discard opened, unused formula after 24 hours, even if refrigerated Unopened formula should be stored at room temperature

48 Frequency of equipment changes Feeding bags/containers manufacturers recommend every 24 hours Syringes (bolus feedings) unlimited must be thoroughly cleaned with soap and water between each feeding

49 Conclusions Patients do NOT benefit from Malnutrition or Starvation EN is the best route for Nutritional Support Optimal Nutritional Support IMPROVES outcomes Optimal Nutrition requires the patient to receive nutrition -- appropriate timing, amount and formulation

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