Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
The What, Why and When
of Permissive
Underfeeding
Ainsley Malone, MS, RD, CNSD
Nutrition Support Team
Mt. Carmel West Hospital
Mt. Carmel West
500 bed academic center
Non-physician based NST
•
Dietitian, pharmacist and nurse
What to Expect
Review rationale for underfeeding
Discuss research with parenteral
nutrition and enteral nutrition
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•
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Not always mutually exclusive
In critically ill population
Include obese population
Offer recommendations for practice
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Caloric Intake Quandary
???
•Minimize loss
•Promote clinical
improvement
•Overfeeding
and its
associated
complications
•Positive
outcomes
Paradigm Shift
A change in basic assumptions
within the ruling theory of science
History of Energy Intake
Early PN Regimens
•
•
175% to 200% of BEE
VA Cooperative Trial – 46 kcals/kg
Energy Requirements
•
Long, et al.
• Activity/injury factors
• High estimation of requirements
•
Kcals/kg
• 35 – 45 kcals/kg
• Obese patients using actual weight
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Adverse Effects?
Ventilatory complications reported
•
•
Case reports
Askanazi, et al. 1981
• Increased work of breathing, ventilator weaning failure
VA Cooperative Trial
•
Increased infectious complications seen in those with
mild or moderate malnutrition
Relationship to energy intake and/or
substrate?
Rationale for Underfeeding
Based upon “hormesis” concept
(Zaloga-1994)
•
•
•
“Less is more” theory
Beneficial effect of low dose vs toxic effect
of high dose
In setting of inflammation
• cytokine release,
• oxidant production
• damage
Critical Illness – Metabolic
Response
Flow phase - catabolism
•
Increased counter-regulatory hormones
• Favors catabolic processes
• Increased gluconeogenesis
• General duration of 3-10 days
Flow phase – anabolism
•
•
Decreased glucagon, epi and norepi
Increased growth hormone, IGF
• Favors anabolic processes
• Duration of 10 to 60 days
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Catabolic Phase
Ability to tolerate traditional
nutrient regimens?
Can endogenous glucose
production be suppressed?
Hyperglycemia common
Potential Benefits
Reduced nutrient oxidation
Reduced free radical and cytokine
production
Reduced DNA damage
Reduced metabolic demands
•
Potential for reduced CO2 production
•
Potential Benefits
Energy/carbohydrate restriction
Lower n-6 fatty acids
•
•
Reduced hyperglycemia
Reduced substrate for pro-inflammatory
mediator synthesis
Decreased Ca, Fe, Zn levels
•
May decrease inflammatory response and
cell injury
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Animal Models for
Underfeeding
Alexander, Ann Surg 1989
•
Animals with peritonitis
• Kcal range – 100 to 15 per kg
• Increased infections in higher calorie group
• Increased survival when provided fewer calories
• 100% mortality in high group vs 43% in low group
Berg and Simms, J Nutr 1990
Peck, JPEN 1992
•
•
Rats with restricted diets lived 20% longer
Significantly improved mortality in mice fed 50%
normal caloric intake
Underfeeding in Parenteral
Nutrition
Patino, World J Surg 1999
•
Retrospective of 107 ICU patients
Grouped by use of PN (early versus late)
22-24 kcals/kg day (IBW)
Lack of statistical analysis
Nitrogen balance
•
Glucose levels
•
•
•
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• -8.5 and -9.7
• 122 mg/dl and 135 mg/dl
Concluded results much improved from
earlier hypercaloric regimens
Underfeeding in Parenteral
Nutrition
McGowan, CCM 2000
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•
PRCT in acute care hospital
Compared a hypocaloric and eucaloric regimen
• 1000 kcals/day or 20-25 kcals/kg/day
• Protein provided at 1.5 g/kg/day
• Initiated less than total dextrose goal
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Nutrient intake
•
No difference in glucose levels or infections
Nitrogen balance more negative in hypocaloric group
Concluded that hypocaloric PN regimen not superior
• 913 ± 90 vs 1192 ± 212 kcals/day
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Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Enteral Nutrition and
Underfeeding
Krishnan, Chest 2003
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•
Prospective trial in ICU patients (n=187)
Compared energy intakes with AACP
guidelines
• 25 kcals/kg/day
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Divided energy intakes into tertiles
Average intake 50.6% of the ACCP
• Tertile II with ↑ likelihood of discharge alive
compared to I or III
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Criticism of PN use in up to 39% of patients
Enteral Nutrition and
Underfeeding
Ibrahim, JPEN 2002
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PRCT with ICU patients
Compared early versus late feeding group
• 100% estimated EE on Day 1 versus Day 5
• Late group to receive 20% of EEE Days 1-4
• Total caloric intake = 2370 ± 2000 kcals/day versus
629 ± 575 kcals (p<0.001)
•
Increased ICU LOS (p=0.02), VAP (p=0.04)
and antibiotic therapy (p=0.001) in the early
group
•
Conclusions and caveats
• No difference in mortality
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Enteral Nutrition and
Underfeeding
Ash, JPEN 2005 (abstract)
•
Retrospective review of trauma patients
(n=128)
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Evaluated caloric intakes in quartiles
•
Highest hospital LOS in Quartile IV
• Non-obese
• Kcals/kg/day
Enteral Nutrition and
Underfeeding
Hise, JADA 2007
•
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Prospective evaluation in MICU and SICU
Mean percent of goal energy intake per ICU
day calculated
• Energy intake from all sources
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Higher ICU LOS with >82% of goal intake
SICU population of >67% of goal intake
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Conclusions
•
• Higher ICU and hospital LOS
• Limit energy intake to 80% or less in severe critical
illness
Rationale for Underfeeding in
Obesity
Obese associated with metabolic
changes
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Insulin resistance
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Obstructive sleep apnea
Fatty infiltration
• Hyperglycemia
•
Provide nutrients without exacerbating
metabolic issues
Protect lean body mass
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Obese Patient
Dickerson, AJCN 1986
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•
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Pilot study (n=14)
Prospective evaluation with PN
Received 51% of non-protein kcals
• 2.1 g/protein/kg
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•
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Weight loss occurred
Nitrogen balance +2.4±1.9 g/day
Wounds and fistulas healed
Obese Patient
Burge, JPEN 1994
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Prospective trial in acutely ill patients (n=16)
Randomized to receive 50% or 100% nonprotein kcals
•
Nitrogen balance
•
• 2 g protein/kg
• 1.3 ± 3.62 hypocaloric group
• 2.8 ± 6.9 control group
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Conclusion – hypocaloric PN can result in a
comparable nitrogen balance
Obese Patient
Choban, 1997 AJCN
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•
•
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Prospective evaluation in acute/critically ill
patients (n=30)
22 kcals/kg IBW – hypocalorie
36 kcals/kg IBW – control
No difference in weight change or nitrogen
balance
• ICU patients with no difference
•
•
Trend toward lower glucose levels in
hypocaloric group
Conclusion
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Obese Patients
Dickerson, Nutrition 2002
•
Retrospective evaluation in critically ill
patients (n=40)
• Hypocaloric = < 20 kcals/kg adj BW
• Eucaloric = ≥ 20 kcals/kg adj BW
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Actual energy intake - Average at week 4
• 22 kcals/kg/IBW – hypocaloric
• 29 kcals/kg/IBW - eucaloric
•
No significant differences in nitrogen balance
Obese Patient
Dickerson, Nutrition 2002
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Clinical outcomes
• Decreased ICU stay (p=0.03)
• Decreased antibiotic therapy (p=0.03)
• No difference in glucose levels
• May be related to EN versus PN
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Conclusion
• Hypocaloric EN feeding approach at least AS
favorable is eucloric feeding
• May provide a clinical benefit
Obese Patient
Choban and Dickerson, NCP 2005
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•
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Combined data sets
Evaluated morbidly obese (Class III = BMI ≥
40)
N = 70
• 44 provided hypocaloric regimen
• 26 provided eucaloric regimen
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Via regression determined higher protein
intake is needed
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Trend toward worsening hyperglycemia in
Class III compared to less obese
• 1.9 - 2.5 g/kg/IBW in critically ill patients
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Recommendations
ADA Evidence Analysis Library
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•
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2007 summary on EN delivery in critical illness
Recommends 14-18 kcals/kg actual weight
(non-obese)
Caloric intake preview: energy intake of 9 to
18 kcal per kg may be associated with
decreased mortality
Canadian Clinical Practice Guidelines
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Recommend “low dose” PN
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Refer to lack of prospective trials
• Short duration and in those not malnourished
http://ada.portalxm.com/eal/topic.cfm?cat=3368
Is Underfeeding with EN
Occurring?
McClave, et al, 1999
44 MICU and CCU patients
Nasogastric tubes
Data recorded q 4 hrs
78% of ordered TF delivered
Feeding disruption
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11% - 102%
High residual volume
Procedures
Is Underfeeding with EN
Occurring?
Petros, Clin Nutr 2006
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Observational study of ICU patients
• At least 7 days of EN
• Assess EE via indirect calorimetry
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Caloric target minimum of 20 kcals/kg/day
EN interrupted in 32% of feeding days
Daily infused volume = 86.2 ± 30.4% of prescribed
Mean energy intake
• 39.2% on Day 1
• 83.1% on Day 6
•
Conclusion – Caloric delivery much less than MEE
Clin Nutr 2006;25:51-59
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Contribution to
Underfeeding
Marshall, Intensive Crit Care Nurse
2006
•
•
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Descriptive survey of 376 critical care
nurses on enteral feeding practices
Response rate = 50.5%
Gastric residual volume measurement –
65.4%
• Reason to delay feeding
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Patient positioning (21%) and tube
placement issues (25%)
•
Conclusion
• Decreased enteral feeding intakes
Practice Recommendations
Populations for permissive underfeeding
Suggested energy intakes
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•
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Sepsis, ARDS, trauma, surgical patients
14-18 kcals/kgday in the non-obese
22 kcals/kg/day in the obese
Recommended goal for PN not for EN
Length of underfeeding
•
•
Monitor energy intake via EN
Recommendations are for 7-10 days or when
metabolic response abates
Take Home Messages
Permissive underfeeding an
alternative concept
Preventing overfeeding essential
Animal models supportive
Research with PN and EN and
patient suggests benefit
Actively pursue with PN patient but
not EN
Oklahoma Dietetic Association
Ainsley Malone, MS, RD, LD, CNSD
April, 16, 2008
Permissive Underfeeding: What,
Where and Why?
Thank You!!