What s New in ICU Nutrition

1. What�s New in ICU Nutrition?

2. �A slender and restricted diet is always dangerous in chronic and in acute diseases� Hippocrates 400 B.C.

3. ��do not let your patients starve and when you offer them nutrition support, do so by the safest, simplest, most effective route.� Dr Mike Stroud Feb 2006 Chair of NICE committee

5. 1970s: TPN - separate CH, AAs and Lipids Single lumen C/Lines, no pumps 2500-3000kcals/day: Lactic acidosis, high glucose loads, fatty livers, high insulin reqt 1980s: Scientific studies of metabolism: recognition of overfeeding, excess nitrogen 1990s: nitrogen limitation: 0.2g/kg/24hr, start of immuno-nutrition trials 2000s: glucose control, specific nutrients

6. Metabolic Responses in Severe illness Aims to mobilize substrate (amino acids and fatty acids) from body stores to support vital organs � catabolism - Protein redistribution from skeletal muscle to support the central viscera: wasting Aims to enhance resistance to infection: inflammatory cascade

7. Metabolic Demands and Response in Severe Illness Extreme physiological stress/organ failure Increased oxygen requirements High body temperature Acute phase response: cytokines Sympathetic nervous system stimulation Immuno-suppression Insulin resistance: hyperglycaemia Impaired gut function

8. Starvation Bobby Sands � lost 7 kg in first 17 days Died at 65 days (9 weeks) Not expending excess energy, not in ICU Weight loss approx 0.3kg/day after first week depending on activity/health Loss of muscle and fat Eventual death from slowing of all metabolic processes

9. Metabolic response to starvation Aims to minimize impact on vital organs and conserve energy Decreased metabolic rate Decreased temperature Reduction in physical activity ICU patients � often have starvation AND increased metabolic demands Complex metabolic and inflammatory processes �

10. Consequences of malnutrition Increased morbidity and mortality Prolonged hospital stay Impaired tissue function and wound healing Defective muscle function, reduced respiratory and cardiac function Prolonged weaning from ventilation Immuno-suppression, increased risk of infection Depression, lethargy

11. Scale of the problem McWhirter and Pennington 1994: >40% of hospital patients malnourished on admission Recent Scottish data 35% Estimated cost to hospitals: �3.8bn/yr Many ICU patients malnourished or at risk on ICU admission

12. The Downward Spiral of Malnutrition in ICU

13. SICS Nutrition Network Set up in June 2006 Links dietitians, pharmacists, ICU nurses, physios and doctors. Meets 3x/year Forum for sharing ideas Current projects on assessment/weighing Guidelines on practical issues Website with protocols/guidelines/teaching Educational meetings Encouraging projects in nutrition

14. National Initiatives QIS Standards MUST (BAPEN) NICE guidelines on Hospital Nutrition Charge Nurse Review

15. What are we good at? Feeding within 48 hours Reminding the surgeons about it Putting tubes in Giving TPN Looking after lines

16. What are we less good at? Nutritional screening Weighing patients Keeping tubes in Maintaining NG intake NJ feeding � practical issues Treating complications Identifying refeeding risk or syndrome Feeding in HDU

17. Nutritional State

18. Nutritional Assessment Various nutritional screening tools None very good for ICU Malnutrition Universal Screening Tool from the Malnutrition Advisory Group of BAPEN Uses BMI, weight loss, acute illness/intake Low risk-routine care, Medium - observe High risk: treat- �refer to dietitian/local protocols�

19. Screening in ICU MUST not very helpful in guiding decisions Almost all patients require artificial nutrition- cannot �observe� What about refeeding syndrome? Needs adaptation using NICE Guidelines Adapted MUST for ICU: Uses BMI/weight loss/food intake + refeeding risk assessment; linked to feeding flowchart

20. SNACC 1. Pilot study of Fife ICU screening tool 08 2. Systematic review of nutritional assessment in critical care: 09 3. Large study of screening tool in Scotland to compare it with other screens and look at outcome data � results may be useful to target interventions 2010-11

21. Weighing Patients Craig Hurnauth ICU S/N at SJH Audit of 13/14 NHS trusts in Scotland 12 trusts do not weigh patients in ICU on admission; use estimate/notes/family 1 weighs every day with hoist + weekly 5 use MUST 7 do not screen, 1 adapted screening tool 7 units in England � similar results

22. Weighing Patients Important for nutrition screening Drug dosages Cardiac output monitoring � LIDCO, PAFC, PICCO Fluid balance

23. Weighing Patients Estimation of weight can be up to 20% out: i.e. 80 kg instead of 100kg and vice versa Estimation of height also inaccurate but measuring height with tape fairly accurate We need to weigh patients in ICU and measure height

24. Methods of Weighing Hoist: time consuming, needs several nurses, risky for unstable patients or trauma patients Weigh beds �16000 each Digital bed scales � scales for each wheel of the bed � weighs bed + patient, mobile, minimal manpower, no disruption to patient

25. Methods of Weighing Progress since audit: 2 units have bought weigh beds 5 are considering bed scales

26. Keeping tubes in Sedation Stitching Posey Mitts Nasal Bridles

27. Maintaining NG intake Follow a protocol Gastric residuals: do not stop or reduce feed until you have 3 residuals of >250mls (check clinical signs) 400mls may be ok Starting and stopping feed: Extubations, fasting for theatre, scans, minor procedures Can catch up on feed that is missed Keep 10mls/hr if possible � gut protection

28. NJ feed: patient use per year

29. NJ feeding Bypasses the stomach Good for high residuals � gastroparesis High anastomoses Nervous surgeon syndrome Insertion: theatre, bedside, radiology, endoscopy May reduce aspiration, will increase feed given in selected patients

30. Complications Ileus � trickle of feed may be beneficial Avoid opioids, optimise fluid balance and electrolytes, consider Neostigmine Constipation: treat with appropriate drugs Diarrhoea: exclude infections, optimise fluid balance and electrolytes, replace loss ??fibre feeds Intolerance: ? Sepsis, prokinetics, NJ feeding, avoid opioids Line sepsis - SPSP

31. Overfeeding Lactic acidosis Hyperglycaemia Increased infections Liver impairment (Alk phos, ALT, GGT, acalculous cholecystitis) Persistent pyrexia Exact requirements calculated by dietitians (generally less than in the fit) 25kcal/kg/24hours rough guide, 10 in refeeding risk

32. Refeeding Syndrome Prisoners of war 1944-5, 1944: conscientious objectors in USA studied Starvation: early use of glycogen stores for amino acids - gluconeogenesis 72 hrs: fatty acid oxidation; use of fatty acids and ketones for energy source, low insulin levels Atrophy of organs, reduced lean body mass

33. Refeeding syndrome Carbohydrate feeding: shift to CH metabolism Insulin release Phosphate and potassium shift into cells. Magnesium, potassium and phosphate drop May get Lactic acidosis Sodium and water shift out of cells � oedema Insulin causes sodium retention Protein synthesis needs potassium and phosphate - these drop more Thiamine deficiency occurs (co-factor in CH metabolism): encephalopathy, weakness

34. Refeeding Syndrome in ICU Unlikely to be a clear diagnosis Many effects: oedema, arrhythmias, pulmonary oedema, cardiac decompensation, respiratory weakness, fits, hypotension, leukocyte dysfunction, diarrhoea, coma, rhabdomyolysis, sudden death Screen: nutritional history and electrolytes Remember in HDU patients/malnourished ward patients Poor awareness among doctors!

35. Risk of re-feeding syndrome Two or more of the following: BMI less than 18.5 kg/m2 (<16) unintentional weight loss greater than 10% within the last 3-6 months (>15%) little or no nutritional intake for more than 5 days (>10) Hx alcohol abuse or drugs including insulin, chemotherapy, antacids or diuretics (Critically low levels of PO42-, K+ and Mg2+)

36. Managing refeeding problems provide Thiamine (Pabrinex)/multivitamin/trace element supplementation start nutrition support at 10 kcal/kg/day increase levels slowly restore circulatory volume monitor fluid balance and clinical status replace phosphate, magnesium and K+ Reduce feeding rate if problems arise NOTES FOR PRESENTERS Please refer to the NICE Quick Reference Guide � page 19NOTES FOR PRESENTERS Please refer to the NICE Quick Reference Guide � page 19

37. Intake in HDU

38. Feeding in HDU

39. ACTION Establish guidelines for feeding Identify high-risk patients/refeeding risk Aim for oral/NG supplementation in these patients Aim to improve fluid administration ERAS/Pre-op supplements Monitoring of calorific requirements/intake Dietitian follow-up to wards

40. Immuno-nutrition The immune system: a complex and interactive biological system that coordinates the detection, destruction and elimination of any foreign material or organism entering the body. Oxidants: cytokines, NFkB, genes, inflamn Nutrients: glutamine, FFAs, protein Glutathione: oxidant defence Anti-inflammatory molecules

41. THE ICU GAMBLEHow to tip the scales?

42. Critical Illness Small reductions in mortality over years Increasing problems with infection Advances in treatment have limited effects Patho-physiology complex The future: replacement of the body�s own �stress substrates� �Disease-modulating� nutrients Reduce oxidant and metabolic stress Favourably modulate immune response

43. Glutamine Amino acid �essential in sepsis/major trauma Levels drop after injury, exercise and stress. Very low in critical illness first 72 hours Vital to gut, immune cells, and kidney Serves as metabolic fuel; precursor to DNA synthesis, decreases inflammation Glutamine deficiency at onset of critical illness/sepsis correlated with increased mortality Studies in burns/trauma show improvement Big studies in all ICU patients awaited

44. PROBIOTICS �live micro-organisms which when administered in adequate amounts confer a health benefit on the host�

45. Probiotics Critical illness causes virulence of gut bacteria; treatment worsens gut function Probiotics inhibit growth of pathogenic enteric bacteria, eliminate pathogenic toxins block epithelial invasion by pathogens enhance T-cell and macrophage function Potential to cut VAP and C. diff BUT: safety concerns � dose, type,storage unforeseen effects: more research needed

47. Dietary Lipids Ratios in paleolithic diet ?6:?-3 1:1 Current Western diet 16:1 Current UK PN Soybean oil base 7:1 New PN (�SMOF�) 2.5:1 Cell membrane composition depends on balance AA, DHA and EPA are present in inflammatory cell membrane phospholipids Increased ?-3 levels reduce the inflammatory response in various ways: gene expression, cell activity, adhesion molecules, cytokines

48. Antioxidants Oxidative stress in critically ill patients contributes to organ damage / malignant inflammation (free radicals, mitochondrial damage) Glutathione, Vitamins A, C and E Zinc, copper, manganese, iron, selenium Already added to feeds Should we give extra? Results of SIGNET and REDOXs awaited

49. What is the evidence in ICU? Early enteral feeding is best Hyper/hypoglycaemia/overfeeding are bad Starvation and refeeding are bad Nutritional deficit a/w worse outcome EN a/w aspiration and VAP PN �if can�t have EN; soon if malnourished Combination can be used to achieve goals Protocols improve delivery of feed Some nutrients show promising results