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Pharmaconutrition: Selected Nutrients and Their Influence on
Patient Outcomes
The Canadian Clinical Practice Guidelines
Daren K. Heyland, MD, FRCPC, MSc
Queen’s University, Kingston, Ontario
www.criticalcarenutrition.com
Updated July 2006
Immunonutrition: Cocktail Approach?
• Specific nutrients found to have effects on immune system, metabolism, and GI structure and functionArginineGlutamineOmega-3 fatty acidsNucleic acidsothers
• Individual effect on clinical outcomes?
Insult
• infection• trauma• I/R• hypoxemic/ hypotensive
Activation ofPMN’s
= oxidative stress
Death
organ = failure
Pathophysiology of Critical Illness
mitochondrial dysfunction
Role ofGIT
Key nutrient deficiencies(e.g. glutamine, selenium)
activation of coagulation/complement
generation of OFR (ROS + RNOS)
endothelial dysfunction
elaboration of cytokines, NO, and other mediators
cellular = energetic failure
Arginine
Elective Surgical Patient
• cellular immune dysfunction – T-cell
• decrease cytokine activation – IL-2, IFN
Elective Surgical Patient
arginase
arginine
expression of zeta chain
Taheri Clin Cancer Res 2001 ;7:958
=
1.18 (0.88,1.58)
Elective
Surgery
Critically Ill
General Septic Trauma Burns Acute Lung Injury
Arginine
Glutamine
Omega 3 FFA
Antioxidants
Population
Nutrients
Which Nutrients?Which Patients?
Canadian Clinical Practice Guidelines JPEN 2003;27:355
www.criticalcarenutrition.com
Underlying Rationale for Framework
o No scientific rationale for combining nutrients together; need to consider them alone
o Empirical evidence that the nutrients have different treatment effects across populations
Elective
Surgery
Critically Ill
General Septic Trauma Burns Acute Lung Injury
Arginine Benefit No benefit Harm No benefit No benefit No benefit
Glutamine Possible Benefit
PN Beneficial
(? receiving EN)
… EN Possibly
Beneficial
EN Possibly
Beneficial
…
Omega 3 FFA
… … … … … Possible Benefit
Antioxidants … Possible Benefit
… … … …
Population
Nutrients
Which Nutrient for Which Population?
Canadian Clinical Practice Guidelines JPEN 2003;27:355
Arginine-supplemented diets?
Mitaka Shock 2003;19: 305
Underlying PathophysiologyRole of Nitric Oxide
cNOS
cNOS + iNOS
Eff
ect o
f A
rgin
i ne
ind u
ced
NO
for
mat
ion
Har
mfu
lB
enef
itia
l
Arginine / NO availability
Optimal NO-Balance
- Hemodynamic instability- Immune Suppression- Cytotoxicity- Organe dysfunction
- Microcirculation - Immune augmentation
Suchner Brit J Nutrition 2001
Effect of Arginine-supplemented diets on
Mortality
www.criticalcarenutrition.com
www.criticalcarenutrition.com
Effect of Arginine-supplemented diets on
Infectious complications
• Possible mortality in septic pts.
Crit Care Med 1995;23:436
Dent, Crit Care Med 2003
Bertolini Int Care Med 2003;29:834
cost.
• Lack of treatment effect.
But what about ...
Effect of Arginine-supplemented diets in Critically Ill Patients
Glutamine supplementation?
Potential Beneficial Effects of Glutamine
Fuel forFuel forEnterocytesEnterocytes
Fuel forFuel forLymphocytesLymphocytes
Nuclotide Nuclotide SynthesisSynthesis
Maintenance ofMaintenance ofIntestinalIntestinalMucosal BarrierMucosal Barrier
Maintenance ofMaintenance ofLymphocyteLymphocyteFunctionFunction
Preservation Preservation of TCA Functionof TCA Function
Decreased FreeRadical availability (Anti-inflammatory action)
GlutathioneGlutathioneSynthesisSynthesis
GLNGLNpoolpool
GlutamineTherapy
Enhanced HeatEnhanced Heat Shock ProteinShock Protein
Anti-cataboliceffect
Preservation of Muscle mass
Reduced Reduced TranslocationTranslocationEnteric BacteriaEnteric Bacteriaor Endotoxinsor Endotoxins
Reduction ofReduction ofInfectious Infectious complicationscomplications
Inflammatory Cytokine Inflammatory Cytokine AttenuationAttenuation
NF-BNF-B??
Preserved CellularEnergetics- ATP content
GLNGLNPoolPool
Critical IllnessCritical Illness
Enhanced insulin sensitivity
Effect of Glutamine:A Systematic Review of the Literature
www.criticalcarenutrition.com
Infectious Complications
Effect of Glutamine:A Systematic Review of the Literature
www.criticalcarenutrition.com
Mortality
Results of subgroup analysis
EN vs PN?
Mortality Infection
EN 0.80 (0.45-1.43)
P=0.46
0.83 (0.64-1.08)
P=0.16
PN 0.67 (0.48-0.92)
P=0.01
0.75(0.54-1.04)
P=0.08
Benefit of Parenteral Glutamine in Patients on
EN?
Fish Oil supplemented diets?
Mechanisms of Action
• Mediator formation depends on the phospholipid fatty acid content of arachidonic acid (AA) in inflammatory cell membranes
• It is possible to modulate the content of AA in inflammatory cell membranes by changing lipid composition of the diet
Borage Oil
DGLA
PGE1 and LessInflammatory Eicosanoids
Substitution of AABy DGLA
resulting in:
Fish Oil
GLA EPA
Less Inflammatory Eicosanoids
(TXA3, PGE3, LTB5)
Substitution of AABy EPA
Resulting in:
Arachidonic Acid
CyclooxygenaseLipoxygenase
Pro-InflammatoryEicosanoids
(LTB4, TXA2, PGE2)
Decrease in
Mechanisms of Action
Effect of Fish Oils/Borage Oils and antioxidants in Critically Ill
with ALI
• RCT of 146 critically ill patients with ALI and BAL+ for WBCs
• Double-blinded; ITT
• Experimental: Oxepa®
• Control: high fat diet
• Groups well matched at baseline
0
5
10
15
20
25
VentDays
ICUDays
ICUDeaths
Oxepacontrol
Gadek Crit Care Med 1999;27:1409
P=0.03 P=0.17P=0.02
Effect of Fish Oils/Borage Oils and antioxidants in Critically Ill
with ALI• RCT of 100 critically ill
patients with ALI
• Single center
• unblinded; not ITT
• Experimental: Oxepa®
• Control: high fat diet
• Oxepa associated with improved oxygenation and lung compliance
0
10
20
30
40
50
60
VentDays
ICUDays
ICUDeaths
Oxepacontrol
Singer Crit Care Med 2006:34;1033
Effect of Fish Oils/Borage Oils and antioxidants in Critically Ill
with ALI• RCT of 165 critically ill patients
with ARDS secondary to sepsis
• Double-blinded; not ITT
• Experimental: Oxepa®
• Control: high fat diet
• Oxepa associated with:
• improved oxygenation
• More Vent free days
• More ICU free days
• Fewer new organ failures
05
101520253035404550
VentDays
ICUDays
ICUDeaths
Oxepacontrol
Pontes -Arruda Crit Care Med 2006:34;2345
P=0.04
Overall Effect on Mortality
www.criticalcarenutrition.com
• treatment effect of antioxidants?
• treatment effect of borage oils?
• comparison to standard enteral feeding products?
Interpretation of Studies?
How do you interpret the findings?
Antioxidant-supplemented specialized diets?
OFRCONSUMPTION
OFR
PRODUCTION
Depletion ofAntioxidant Enzymes
OFR Scavengers Vitamins/Cofactors
InfectionInflammation
Ischemia
OFR production > OFR consumption =Impaired- organ function- immune function- mucosal barrier function
Complications and Death
OXIDATIVESTRESS
Rationale for Antioxidants
• Endogenous antioxidant defense mechanisms• Enzymes (superoxide dismutase,
catalase, glutathione perioxidase, glutathione reductase including their cofactors Zn and Selenium)
• Sulfhydryl group donors (glutathione)• Vitamins E, C, and B-carotene
Rationale for Antioxidants
1 . P re -e x is t in g d e f ic ie n c ie s - d u e to o ld a g e , s m o k in g , m a ln u tr i tio n , c h ro n ic d is e a se s
2 . In c re a s e d re q u ire m e n ts - h ig h a n tio x id a n t c o n s u m p tio n fro m h ig h ra d ic a l fo rm a tio n - h ig h d e m a n d s in h yp e rm e ta b o lis m
3 . In c re a s e d lo s s e s - s k in e xu d a te in b u rn s , b lo o d lo s s , d ia ly s is , g a s tr ic a s p ira te , in te s tin a l
f is tu la
4 . R e d u c e d s u p p ly - p o s ttra u m a tic , p o s to p e ra tiv e d e la y o f a d e q u a te n u tr i tio n / a n tio x id a n t
s u p p ly - in te r ru p t io n s in n u tr ie n t s u p p ly b e c a u s e o f c l in ic a l / d ia g n o s tic
p ro c e d u re s
Rationale for Antioxidants
Effect of Combined Antioxidant
Strategies in the Critically Ill
Effect on Mortality
Elective
Surgery
Critically Ill
General Septic Trauma Burns Acute Lung Injury
Arginine Benefit No benefit Harm No benefit No benefit No benefit
Glutamine Possible Benefit
PN Beneficial
(? receiving EN)
… EN Possibly
Beneficial
EN Possibly
Beneficial
…
Omega 3 FFA
… … … … … Possible Benefit
Antioxidants … Possible Benefit
… … … …
Population
Nutrients
Which Nutrient for Which Population?
Canadian Clinical Practice Guidelines JPEN 2003;27:355
1200 ICU patientsEvidence of
organ failureR
glutamine
placebo
ConcealedStratified by
site
R
R
antioxidants
placebo
Factorial 2x2 design
placebo
antioxidants Shock
REducing Deaths from OXidative Stress:
The REDOXS study
Critical Care Nutrition Web Site
www.criticalcarenutrition.com – web based clinical practice
guidelines– summaries of evidence – online survey of current practice– benchmarking (other sites and
the clinical practice guidelines) – tools (protocols, etc)– research related news