Transcript Nutrition in Surgical Patients

Nutrition in Surgical Patients
Ronald Merrell, MD
Chairman of Surgery
Virginia Commonwealth University
What?
•
•
•
•
•
Carbohydrate
Lipid
Protein
Trace elements
Vitamins
Who?
• Malnourished (>10% lean body mass)
• Incapable of eating (>10 days)
Why?
• Risks of malnutrition including infection,
poor healing and higher mortality
• Malnutrition is exacerbated by
physiological stress
When?
•
•
•
•
Preoperative?
Early?
Late?
---after initial resuscitation following injury
or surgery
How?
•
•
•
•
Parenteral
Enteral
Total
Partial
Issues
•
•
•
•
Metabolic response to injury
Cytokines, inflammation, hormones
Biology of substrates
Enteral vs. Parenteral
“Ashen faces, a thready pulse
and cold clammy extremities…”
The Ebb Phase
Cuthbertson, Quart. J.
Med.25:233,1932
The Ebb Phase
•
•
•
•
Hypometabolic
Hypothermic
Hypoinsulinemic
Hypoperfusion
•
•
•
•
Hypercortisolism
Hyperglucagonemia
Hyperglycemia
Hypercatecholemia
“The patient warms up,cardiac
output increases and the surgical
team relaxes…”
The Flow Phase
Cuthbertson. Lancet 1:233, 1942
The Flow Phase
• Hypermetabolic
• Hyperthermic
• Catabolic
•
•
•
•
Hyperinsulinism
Hypercortisolism
Hyperglucagonemia
High cardiac output
Nutritional Assessment
•
•
•
•
Body weight
Body mass index
creatinine height index
Serum proteins:albumin, prealbumin,
transferrin
• Immune competence: lymphocytes, DH
• Nitrogen balance
Caloric Requirement
•
•
•
•
Formula
Indirect calorimetry
PRN for nitrogen balance
Approximation
Nutritional Requirements
•
•
•
•
•
25 cal/kg/day
carbohydrate ~70%
Lipid 15-30%
Protein 1.5-2.0g/kg/day. Not for calories
Additional 50% to 100% for stress as in
ICU patients
Nutritional Goals
•
•
•
•
•
Nitrogen balance
Preserve or restore visceral protein
Reduce morbidity
Reduce mortality
Reduce hospital stay
Early Enteral Feeding: a metaanalysis
• Eight prospective randomized trials with
trauma and high risk surgical patients(118
enteral, 112 parenteral)
• Septic complications:enteral 18%,
parenteral 35%
• Moore. Ann. Surg. 216:172,1992
Parenteral requirements
• Dilution in right heart return because of
hyperosmolarity…….Central Venous Line
• Delivery of simple carbohydrate
(20%glucose)
• Lipid emulsion
• Amino acids
Enteral Requirements
• Delivery into the GI tract by tube with
minimum risk of aspiration or patient effort
• Delivery of nutrients with minimal need for
digestion
• Control of rate to prevent osmotic diarrhea
Advantages of enteral nutrition
•
•
•
•
Easier
GI bacterial translocation
Cheaper
Fewer specific complications
Nutrients with specific putative
contributions
•
•
•
•
•
Branch chain amino acids
Glutamine
Arginine
Nucleotides
Omega-3 fatty acids
Immune Enhancing Diet
• Arginine, nucleotide, fish oil
• Shorter stay, fewer infections
• Bower Critical Care Medicine. 23:436,
1995
•
•
•
•
•
•
Parenteral Nutrition
Immunosuppressive
IF...
Poorly administered
Hyperglycemia
No nucleotides
No arginine
No taurine
Excessive fats
Overfeeding with parenteral diets
• Carbohydrate: hyperglycemia, hypercarbia,
fatty liver
• Lipids: hypertriglyceridemia, hypoxia,
infection
• Protein: azotemia
Conclusions
• Nutrition is a powerful determinate of
patient outcome
• The proper provision of nutrition is a
component of basic patient care
• Nutrition is a precise and potentially very
hazardous form of intervention