total enteral nutrition and total parenteral nutrition in critically ill patients
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Prof. mridul panditrao, discusses intricate problems of starvation, the pathophysiological changes, Total enteral nutrition, total parenteral nutrition, various protocols etc...TRANSCRIPT
Total Enteral Nutrition
& Total Parenteral
Nutrition in Critically Ill
Patients
Dr. M. M. PANDITRAO
CONSULTANT
DEPARTMENT OF ANESTHESIOLOGY &
INTENSIVE CARE PUBLIC HOSPITAL AUTHORITY’S
RAND MEMORIAL HOSPITALFREEPORT, GRAND BAHAMA
THE BAHAMAS
Normal Energy & Protein Requirements
Proteins 10-20% Carbohydrates
& 80-90% Fats
Normal Energy & Protein Requirements (Contd.)
• Energy supply by 3 components • Exception:- Some organs viz. central
nervous system, red blood cells, marrow tissue
• Traumatized/Damaged issues• These tissues are absolutely and
obligatory demanders of glucose for their energy derivation.
Starvation
Definition
Lack of exogenous energy substrate and may be relative or absolute.
Hospital Malnutrition:Prevalence
• Numerous studies on hospital malnutrition have been published.
• Prevalence of malnutrition in U.S. hospitals today ranges from 30% to 50%.
• Patient’s nutritional status declines with extended hospital stay. Coats KG et al. J Am Diet Assoc 1993
Malnutrition Among Hospitalized Patients:
A Problem of Physician Awareness
• Up to 50% of hospitalized patients may be malnourished on admission
• Before nutritional assessment training: – Only 12.5% of malnourished patients are identified
• After 4 hours of training:– 100% of patients are
identified
Roubenoff et al. Arch Intern Med 1987
Prevalence of Malnutrition in
Hospitalized Patients
69% Adequate Nutritional State
21% ModeratelyMalnourished
10% Severely Malnourished
Detsky et al. JPEN 1987
Prevalence of Malnutrition in
Hospitalized PatientsIn a published British study:
• 46% of general medicine patients • 45% of patients with respiratory
problems• 27% of surgical patients• 43% of elderly patients
Percentage of malnourished patients at time of admission
McWhirter et al. Br Med J 1994
Malnutrition and its Consequences
• Changes in intestinal barrier• Reduction in glomerular
filtration• Alterations in cardiac function• Altered drug pharmacokinetics
Roediger 1994; Green 1999; Zarowitz 1990
Malnutrition and its Consequences
• Loss of weight• Slow wound healing• Impaired immunity • Increase in length of hospital
stays• Increased treatment costs• Increase in morbidity &
mortality
Malnutrition and Increased Complications
Many studies have shown that complications are 2 to 20 times more frequent in malnourished patients than in well-nourished patients.
Buzby et al. Am J Surg 1980Hickman et al. JPEN 1980
Klidjian et al. JPEN 1982
Marasmic starvation/ malnutrition
• Conservation of energy and proteins
• Stored substrates are utilized sparingly
• Fate is depending upon availability of energy and proteins
Utilization of Substrates
Starvation
• Muscles derive energy by the Oxidation of lipids
• Glycogen depletion augments lipolysis
• Glycerol and free fatty acids are released
• The liver synthesizes acetoacetate and beta hydroxybutyrate
• Keto-adaptation
Starvation
• Gluconeogenesis • Proteins are catabolised to form
glucose viz. carbohydrate residues of
amino acids • Glycerol and lactate from Lipid
Pathway
Starvation
Ketoadaptation is followed by :• Breakdown of proteins decreases • Utilization of glucose as main
substrate decreases• Ketones are used by tissues like
brain • Urea is replaced by mainly ammonia • Excretion of ammonia rises, with
help of glutamine
Critically ill patients
When these processes are correlated in response to the injury (trauma) &/ or sepsis, we can differentiate them in 2 classical phases:
1) Ebb phase 2) Flow phase.
Metabolic Response to Trauma
Time
Ener
gy E
xpen
ditu
re
Ebb PhaseEbb
PhaseFlow
PhaseFlow
Phase
Cutherbertson DP, et al. Adv Clin Chem 1969;12:1-55
Ebb phase
As happens in normal response to starvation, there is no dearth of availability of substrate but actually an inability or decreased ability to utilize it. Gluconeogenetic activity takes over, leading to increased protein breakdown and decrease in lean body mass.
Metabolic Response to Trauma:
Ebb Phase • Characterized by hypovolemic shock• Priority is to maintain life/homeostasis
Cardiac output Oxygen consumption Blood pressure Tissue perfusion Body temperature Metabolic rate
Cuthbertson DP, et al. Adv Clin Chem 1969;12:1-55Welborn MB. In: Rombeau JL, Rolandelli RH, eds. Enteral and Tube Feeding. 3rd ed. 1997
Flow phase
After duration of days to weeks, increased metabolic activity, process of repair / regeneration is initiated and recovery phase starts with increased energy demand. If the supply is well maintained, then the organ function and structure is restored and normalcy is achieved.
Metabolic Response to Trauma:
Flow Phase• Catecholamines• Glucocorticoids• Glucagon• Release of cytokines, lipid
mediators• Acute phase protein production
Cuthbertson DP, et al. Adv Clin Chem 1969;12:1-55Welborn MB. In: Rombeau JL, Rolandelli RH, eds. Enteral and Tube Feeding. 3rd ed. 1997
Necrobiosis
• Massive trauma / overwhelming sepsis / infection.
• Improper, inadequate or inappropriate measures of correction, shock.
• Inherent failure of homeostatic mechanism.
• Any additional systemic / metabolic disorders, burns.
Then as a result of failure of
multiple organ systems – death ensues as the final outcome
Stress starvation
Hypoalbuminemia & Oedema• Severe acute inflammatory response
mediated through the cytokines • Transmigration of proteins (albumin)
to extra vascular compartment • Oedema, hypovolemia and
haemodynamic instability
Stress starvation (Contd.)
• Adaptative strategies as in “normal” starvation glycogenolysis, lipolysis and ketoadaptation: fail
• “Gluoneogenesis” is the only alternative pathway : especially by catabolising proteins (muscles) leading to severe negative nitrogen balance & grave sequelae
What’s to be done?
• Metabolic response to critical illness • Supportive strategies • Adequate nutritional support at right time via right route
in a right proportion Outcome
• Significantly decreasing morbidity and mortality in critically ill patients
Nutrition : Basic Principles1. Critically ill : Prone for high energy
expenditure and rapid protein breakdown. E N initiated within 24 hours of admission significantly reduces morbidity.
2. Parenteral support to be administered to all patients who cannot tolerate enteral regimen within 5 days of starvation.
3. Factors to be taken into consideration: preoperative fasting status/ level of
starvation before ICU admittance, number of days anticipated on ventilator and any associated systemic problems.
Nutrition : Basic Principles4. Intra-operative Jejunal access for
enteral nutrition: better option 5. Optimization of protein and energy
requirement (avoid over/ under feeding)
Protein input - 1.5-2.5 g/kg/day with 50% of total administered enterally
Total caloric intake of 1500-2000 kcal/ day is to be achieved (25 kcal/kg/day ) as per BEE
6. Appropriate electrolyte supplementation : Na
P, K & Mg supplementation
Nutrition : Basic Principles
7. Substrate for provision of energy is carbohydrates and lipids in the ratio of 70:30. Peripheral insulin resistance and
hyperglycemic state, mainly due to impaired glucose utilization and
gluconeogenesis. Overzealous administration of glucose ( eg: >
5 mg/kg/day) will increase the susceptibility to infection.
8. Proper selection of volume, composition and route of administration, for patients with
Renal & hepatic insufficiency Cardio-pulmonary diseased
Nutrition : Basic Principles
9. Critical monitoring essential10.High degree of suspicion and
constant “looking out” for complications
11.Immunonutriton is still a contentious issue, especially in terms of final outcome!
Pre requisites:1. Routine history taking 2. Assessment of physical status 3. Comparative assessment of
approximate weight & weight loss4. Periods of fasting/ starvation5. Investigations:- blood urea, serum
creatinine, serum electrolytes and serum proteins
Albumin level of less than 3.5g/dl is indicative strongly of sepsis and associated with high post- abdominal surgical morbidity and mortality.
Pre requisites: (Contd.)6. Nutritional requirements : Protein
requirements in terms of ‘Nitrogen balance’ (NB)
N.B. = N (in) – N (out)* = Protein _ N (out)
6.25 (gm/day) * N (out) = Urine Urea N/0.8 (gm/day) + GI
losses (2 – 4 gms/ day) + cutaneous losses (0-4
gm/day) = Urine Urea N + 4 -- as a constant factor
0.8
NB =(Protein intake) – (Urine urea nitrogen + 4) 6.25
0.8 keep positive nitrogen balance of 2
– 4 gm / day
Pre requisites: (Contd.) Calculating Basal Energy
Expenditure (BEE)
• Harris-Benedict Equation– Variables gender, weight (kg), height
(cm), age (years) Men: 66.47 + (13.75 x weight) + (5 x height) –
(6.76 x age) Women: 65.51 + (9.56 x weight) + (1.85 x height) –
(4.67 x age)
Calorie requirement = BEE x Activity factor x Stress factor
Pre requisites: (Contd.)
7. Resting Energy Eexpenditure (REE)
REE = BEE x 1.1 – 1.4 Old Concept :Injury, sepsis and
burns increase energy requirements by 30%, 60% and 100%.
Actual requirement rises only by 14% more than calculated BEE
Calories to be supplied are not more than calculated REE
Asknazi J. et al Ann Surg 1980Frankenfield D C et al Crit Care Med 1994
8. Electrolyte requirements • Na+ : 100-120 meq/day • K+ : 80 – 120 meq/day• Mg+ : 12 – 15 mmol/day • Ca+ : around 5 mg/day • Phosphorus : 14 – 16 mmol/day
Pre requisites: (Contd.)
Pre requisites: (Contd.)
9. Micro Nutrients Agent Requirement/
day
Iron 0 – 2 mg
Zinc 1 – 15 g
Copper 1 -5 g
Chromium 10 – 20 g
Selenium 20 – 100 gManganese 150 -800 mg
Vit E 10 – 50 IU
Vit A 2500 IU
Vit C 300 – 500 mg
Vit D 250 IU
Agent Requirement/day
Vit K 10 mg/week
Thiamine 50 – 250 mg
Riboflavin 5 mg
Niacin 50 mg
Pantothenate
15 mg
Pyridoxine 5 mg
Folic acid 600 g
BIZ 12g
Biotin 60g
Routes & Technologies of Administration
ENTERAL
PARENTERAL
The Total Enteral Nutrition (TN)
DEFINED :
Delivery of all the necessary substrates (Amino acids + Carbohydrates + Lipids) via an access either through the natural anatomical GI route or surgically created one
Benefits of Enteral Nutrition Therapy
• Maintains GIT structure, integrity
and function• Easier, more Physiological• Enhances intestinal immune function• Reduces bacterial translocation• Decreases risk of sepsis• Fewer complications than with
parenteral nutrition• Lower costs, Less expensive
Benefits of Enteral Nutrition Therapy
Improved Patient OutcomesImproved wound healingDecreased risk of complications
– Nosocomial infection
Decreased length of stayDecreased healthcare costs
Benefits of Enteral Nutrition Therapy
Early Intervention as Part of Initial Care
Enteral Nutrition• Oral supplements• Tube feeding
Parenteral Nutrition• Total• Peripheral
If the gut works, use it!”
Techniques of Access
Enteral Contraindications
• Hemodynamic instability• Pressors• Peritonitis• Bowel obstruction• Proximal fistula*• High output fistula• Bowel ischemia
Complications of TEN
Complications Complications of GI access:-
Dislodgements Small bowel volvulus, infarction Catheter/tube occlusion Leakage/skin breakdown Tube malposition
Gastric distention and aspiration Diarrhea and GI complications Other infections
Protocol for TEN • Tube placement, confirmed with X ray• Raise HOB to 30 • Start with 15 ml/hr with increments of 15
ml/hr every 12th hourly to 60 ml/hr.• Continue 60 ml/hr for 24 hrs.• Increments 15 ml/hr every 12 hrly. After
that to reach TEN max of 100 – 120 ml/hr.• Intermittent aspiration (every 4th hourly)
assess if <150 Continue,if < 150 – 300 Prokinetic like
Metaclopramide, if > 300 ml reduce rate by 50% & try
other alternative.• Irrigate tube 4th hourly with 30 ml of
water,12th hourly with 10 ml of sodabicarb.
The Total Parenteral Nutrition (TPN)
DEFINED:
Delivery of all the necessary, required substrates (combination of amino acids + concentrated glucose + lipids) via central vein (to overcome high osmolarity of the preparation due to high concentration of glucose) with the help of a pump for prolonged duration as required in critically ill patients.
The Total Parenteral Nutrition
Access • Subclaviabn ( Right one preferred)• Internal Jugular
Rarely and to be avoided:- • Femoral vein• Median cubital• Any peripheral veins
The Total Parenteral Nutrition
Formulations• Multiple preparations • Energy providers:- Glucose + lipids
(a combination of medium chain + long chain – MCT / LCT : triglyceride) in the ratio of 60% - 70% + 30% - 40%
• Proteins in the form of amino acid preparation provides nitrogen up to 8 – 16 g/lit
• Micro nutrients, electrolytes and other additives like anticoagulants
Complications of TPN • Procedure complications
Pneumothorax, chylothorax, haemothorax, air embolism, hydrothorax
Carotid arterial puncture Subclavian arterial puncture
• Mechanical Wrong position in to the peripheral
vein. Blockade of catheter
• Metabolism related to all electrolytes & glucose
• Infection / Sepsis
Protocol for starting TPN• Confirm proper placement of
central venous catheter • Absolutely thorough aseptic
precautions while handling • Carbohydrates at rate of
– Not more than 4 mg/kg/min– Lipids not more than 0.1 gm/kg/hr
• Infusion pump to be used “all in one” system
• Calculate nitrogen requirement and titrate
• Continuous monitoring
The recent reviews Meta analysis of 5, level 2 randomized controlled trials carried out by Hemdon (1987)8 , Hemdon (1989) 9, Dunham (1994) 10 , Chiarelli (1996) 11 and Bauer (2000) 12 revealed
• Parenteral nutrition in combination
with enteral nutrition in critically ill provides no added benefit to enteral nutrition alone
• Parenteral nutrition with enteral nutrition is associated with high cost to enteral nutrition alone
The recent reviews
Same findings were confirmed by, Dhaliwal R , Jurewitsch B et al,13 after doing systematic review of the evidence
The recent reviewsLatest guidelines about the enteral nutrition and parenteral nutrition in terminally ill cancer patients by Dy SM (2006) 14 confirm
• Enteral and parenteral nutrition combined may help improve survival, functional status and quality of life
• These benefits appear to be primarily limited to the patients with good functional status
• The risks and the complications as mentioned in the past are confirmed
Summary• Recognize when nutritional
support is warranted• Choose route of nutrition (enteral
vs. parenteral)• Plan nutrient prescription• Discuss benefits vs. complications
of enteral and parenteral nutrition• Describe how to monitor patients
receiving nutrition support
Conclusion
• A Few, Basic & Fundamental Concepts
• “Critically ill”: a Misleading word• Multiple Factors have multiple
roles!• Magnitude of Malnutrition—
Unimaginable!• Understand, Estimate, Strategize
and Execute!• EN or PN ?????• Use Your own Discretion!!!!!!