--- 護理人員應備的基本認識 - 台中榮總

全靜脈營養治療

--- 護理人員應備的基本認識

徐中平 醫師

國立陽明大學 外科教授 台中榮民總醫院 臨床營養醫療組召集人 腔外科主治醫師 急診外科主任

Malnutrition

„ Kwashiorkor - Acute

„ Inadequate protein intake

„ Hypoalbuminemia

„ Fatty liver

„ Marasmus – Chronic

„ Inadequate energy intake

„ Subcutaneous fat loss

„ Muscle wasting

„ Marasmic-kwashiorkor

„ Combination of Kwashiorkor and Marasmus

Historical Attempts at Correcting Malnutrition

„ BC - Ancient Egyptians rectal feedings

„ 1596 - Tube feeding via esophagus

„ 1790 - Tube feeding into stomach

„ 1881 - Long-term rectal feedings administered

„ 1910 - Duodenal feeding with weighted tube

„ 1918 - Immediate post gastrostomy jejunal feeding, with milk, dextrose, whisky

„ 1940 - duodenal-lumen tube for jejunal feeding, and gastric aspiration

„ 1944 - Early post-op feeding, casein hydrolysate

„ 1952 - Feeding with fine polyethylene tubes milk, liver protein, eggs, hydrolyzed starch

Landmark Hospital Malnutrition Study

„ Body height not recorded in 56%

„ Body weight not recorded in 23%

„ 61% of those with recorded weight lost

> 6 Kg

„ 37% had albumin < 3.0 g/dL

Butterworth CE, Nutr Today, 1974

Prevalence of Malnutrition in Hospitals

„ Numerous studies on hospital

malnutrition have been published

„ Prevalence of malnutrition in U.S. hospital today ranges from 30% to 50%

„ Patients’ nutritional status declines with extended hospital stay

Cost KG et al, J Am Diet Assoc, 1993

Malnutrition Among Hospitalized Patient: A Problem with Physician Awareness

„ Up to 50% of patients admitted may be malnourished

„ Prior to specific nutritional assessment training

„ Only 12.5% of malnourished patients identified

„ After training (4 hours training)

„ 100% of malnourished patient can be identified

Roubenoff R et al, Arch Intern Med, 1987

Prevalence of Malnutrition in Hospitalized Patients

0%

10%

20%

30%

40%

50%

60%

70%

Distribution of Patients

Severely Malnourished Moderately Nourished Well Nourished

Detsky AS et al, JPEN, 1987 Mobarhan S et al, JPEN, 1987

10% 21% 69%

Prevalence of Malnutrition in Hospitalized Patients

„ 46% of general medical patients

„ 45% of respiratory patients

„ 27% of surgical patients

„ 43% of elderly patients

McWhirter JP et al., Br Med J, 1994

Consequences of Malnutrition in Metabolically Stressed Patients

„ Muscle wasting

„ Severe weight loss

„ Delay wound healing

„ Impaired immunity

„ Multi-organ dysfunction

„ Increased length of stay

„ Higher costs

„ Increased morbidity/mortality

Malnutrition Is Associated

with Increased Complications

„ 42% of patients with severe malnutrition experience major complications

„ 9% of patients with moderate malnutrition experience major complications

„ Severely malnourished patients are four times as likely to have post-operative complications as well-nourished patients

Detsky AS et al., JPEN, 1987 Detsky AS et al., JAMA, 1994

Summary

„ Malnutrition

„ Widely prevalent

„ Associated with

„ Increased morbidity/mortality

„ Increased length of hospital stay

„ Higher costs

„ Nutritional therapy must become an integral part of patient care

Metabolic Response to Starvation and Injury

„ Metabolism of substrates and micro-nutrients is altered in starvation and injury.

„ During starvation, metabolic processes slow down to conserve energy and adapt to caloric deprivation.

„ Following injury, the hormonal milieu of the body is altered increasing the demand for energy, protein, and micronutrients.

„ Failure to recognize and provide nutritional needs during starvation or injury can result in loss of body mass, loss of body protein, and impairment or loss of body function.

Metabolic Response to Starvation

„ ↑Production and utilization of ketone bodies

„ ↑Release and use of free fatty acids

„ ↓Metabolic rate

„ Conservation of visceral protein

Metabolic Response to Starvation

Hormone Source Secretion

change Norepinephrine Sympathetic nerve

system

↓↓↓

Norepinephrine Adrenal gland ↑ Epinephrine Adrenal gland ↑ Thyroid hormone

T4 Thyroid gland

(changed to T3 peripherally)

↓↓↓

Landsberg L et al., N Engl J Med, 1978

Metabolic Response to Injury

Ebb Phase

Flow Phase

Time

Energy Expenditure

Cuthbertson D et al., Adv Clin Chem, 1969

Metabolic Response to Injury --- Ebb Phase

„ Often characterized by hypovolemic shock

„ Priority is life maintenance/homeostasis

„ ↓Cardiac output

„ ↓ Oxygen consumption

„ ↓ Blood pressure

„ ↓ Tissue perfusion

„ ↓ Body temperature

„ ↓ Metabolic rate

Cuthbertson D et al., Adv Clin Chem, 1969

Metabolic Response to Injury --- Flow Phase

„

↑Catecholamines

„

↑ Glucocoticoids

„

↑ Glucagon

„

Release of cytokines, lipid mediators

„

Production of acute phase proteins

Cuthbertson D et al., Adv Clin Chem, 1969

Metabolic Response to Starvation and Injury

Starvation Injury /Illness

Metabolic Rate ↓ ↑↑

Body Fuel conserved wasted

Body Protein conserved wasted

Urinary Nitrogen ↓ ↑↑

Weight Loss slow rapid

The body adapts to starvation but not when accompanied by critical injury or illness.

Popp MB et al., In: Fischer JF, ed. Surgical Nutrition, 1983.

Methods for Determining Caloric Needs

„ Indirect calorimetry

„ Most reliable

„ Harris-Benedict (BEE) x activity factor x stress factor

„ Most popular

„ Rapid method

„ 25-30 kcal/kg body weight

Metabolic Response to Overfeeding

„

Hyperglycemia

„

Hypertriglyceridemia

„

Hypercapnia

„

Fatty liver

Macronutrients During Stress

„

Carbohydrate

„ Minimum of 100 g/day is required to prevent ketosis

„ Carbohydrate level in diet should provide 60-70% of non-protein calories during

stress

„ Glucose intake should not exceed 5 mg/kg/min

Macronutrients During Stress

„

Fat

„ Fat should provide approximately 20-55% of total calories

„ Maximum recommended rate of intravenous fat infusion is 1.0-1.5 g/kg/day

„ Serum triglyceride level should be monitored to ensure proper fat

clearance

Macronutrients During Stress

„

Protein

„ Requirements range from 1.2-2.0 g/kg/day in stress

„ Protein should comprise approximately 20% of total calories during stress

Determining Protein Needs of the Hospital Patient

Stress level Non-stressed Mildly stressed Severely stressed

Kcal/N Ratio ≧150:1 150-100:1 ﹤100:1

% Protein/Kcal ﹤15% protein 15-20% protein ﹥20% protein Protein/kg BW 0.8 g/kg/day 1.0-1.2 g/kg/day 1.5-2.0 g/kg/day

Role of Glutamine in Metabolic Injury

„ Is considered “conditionally essential” for critically ill patient

„ Is depleted following injury

„ Provides fuel for the cells of the immune system and GI tract

„ Helps maintain or restore mucosal integrity

Lacey et al., Nutr Rev, 1990 Smith et al., JPEN, 1990 Pastores et al., Nutr, 1994 Calder, Clin Nutr, 1994

Role of Arginine in Metabolic Injury

„ Supports cells of the immune system

„ Enhances nitrogen retention after metabolic stress

„ Improves wound healing in animal models

„ Secretagogue and precursor for polyamines and nitric oxide

Barbul A, JPEN,1986

Key Vitamin and Mineral Functions

„ Vitamin A

„ Wound healing and tissue repair

„ Vitamin C

„ Collagen synthesis, wound repair

„ B Vitamins

„ Metabolism, carbohydrate utilization

„ Pyridoxine

„ Essential for protein synthesis

„ Zinc

„ Wound repair, immune function, protein synthesis

„ Vitamin E

„ Antioxidation

„ Folic Acid, Iron, B12

„ Necessary for synthesis and turnover of red blood cells

Definition of PNT

„

Parenteral nutritional therapy is intravenous nutrition

„ Partial

„ Complete

„

Routes of access

„ Peripheral vein

„ Central vein

Indication for PNT

„ The American Society for Parenteral and Enteral Nutrition (ASPEN) states that parenteral nutrition should be

considered as an alternative only when enteral access cannot be obtained or when feeding into the GI tract is

contracted, such as:

„ Non-functioning GI tract

„ Inability to use GI tract

„ “Bowel reset” necessary ASPEN, 1993

Benefits of Enteral Feeding for GI Physiology and Functioin

„ ↓Hypermetabolic response to stress

„ Helps prevent stress ulcers

„ Maintains the secretion of gut peptides, secretory IgA and mucin

„ ↓ Loss of nitrogen and protein associated with disuse atrophy

„ ↑Synthesis of digestive enzymes

„ Maintains the absorptive, immune, endocrine functions of the GI tract

„ Maintains the barrier functions of the GI tract to prevent bacterial translocation

Clinical Conditions for PNT

„ Nonfunctioning GI tract

„ Inability to use the GI tract

„ Complete intestinal obstruction

„ Peritonitis

„ Intractable vomiting

„ Severe diarrhea of small bowel origin (>1500 mL/day)

„ Severe small-bowel ileus

„ High-output (>500 mL/day) entero-

cutaneous fistula (unless able to feed via GI tract distal to the fistula)

„ Short-bowel syndrome

„ Severe malabsorption

Contraindication for PNT

„

Ability to consume and absorb adequate nutrients orally or by enteral tube feeding

„

Hemodynamic instability

„

Undefined therapy goals

„

To prolong life in terminal illness

Central Venous PNT

„

Therapy > 10 days

„

Amino acids > 5%

„

Dextrose 50-70%

„

Vitamins, minerals, and trace elements

„

Osmolality > 700 mOsm/L

PNT formula

„

Amino acids

„ Standard concentrations range from 5% to 15%

„ Kcal from amino acids 4 kcal/g

„ N2 = grams of protein/6.25

PNT Protein Sources

„

Standard formulation

„ Crystalline amino acids

„

Renal formulation

„ Essential amino acids and histidine

„ 1 g/hour is removed by PD or HD

„

Hepatic formulation

„ Branched chain amino acids

PNT Formula

„ Lipids

„ use to prevent

essential fatty acid deficiency

„ Used as a source of non-protein kcal

„ Available in 10%, 20%, or 30%

concentrations

„ May be added daily to the base PN

solution or given separately

„ Fatty acid composition

„ Chain length

„ Short chain (≦6 carbons)

„ Medium-chain (7-12 carbons)

„ Long-chain (13-27 carbons)

„ C-bond saturation

„ Saturated

„ Unsaturated

„ MUFA

„ PUFA (ω-3, and ω-6)

PNT Formula

„

Electrolytes

„ Calcium, magnesium, phosphate, chloride, potassium, sodium

„ Forms and amounts are titrated based on metabolic status and fluid and electrolyte balance

PNT Formula

„

Vitamins and Minerals

„ Generally added in amounts lower than RDA for stable patients

„ Added to the PNT solution daily just before infusion

„ Acute illness, infection, pre-

existing malnutrition or excessive fluid losses may increase vitamin needs

PNT Formula

„

Trace Elements

„ Includes zinc, copper, chromium, manganese daily

„ Needs may vary among patients and disease status

„ Long-term PNT patients require the addition of selenium and iron

PNT Monitoring

„ Parameters

„ Body weight

„ N2 balance

„ Visceral protein parameters

„ Creatinine-height index

„ Metabolic

„ Glucose

„ Fluid and electrolyte balance

„ Liver and renal function

„ Cholesterol and triglycerides

PNT Complications

„

Catheter related

„ Insertion

„ Pneumothorax

„ Chylothorax

„ Hemothorax

„ Air embolism

„ Arterial puncture

„ Nerve injury

PNT Complications

„

Catheter related

„ Mechanical

„ Malpositioned catheter

„ Phlebitis

„ Thrombosis

„ Catheter occlusion

„ Rupture

„ Embolus

PNT Complications

„

Catheter related

„ Infection

„ Exit site

„ Tunnel

„ Colonization

„ Bacteremia

„ Systemic sepsis

PNT Complications

„

Metabolic

„ Hyper-or hypoglycemia

„ Electrolyte imbalance

„ Parenteral azotemia

„ Acid/base abnormality

PNT Complications

„

Gastrointestinal

„ Gastritis and ulceration

„ Hepatic dysfunction

„ Gastrointestinal atrophy

PNT Complications

„

Overfeeding

„ More than 35 kcal/kg may lead to

„ Hepatic steatosis

„ Hyperglycemia

„ Increased BUN

„ Hypertriglyceridemia

„ Respiratory distress syndrome

„ Increased CO2 production

ENT Complications

„ Mechanical

„ Irritation or infection

„ Use appropriate tubes and devices

„ Tube displacement

„ Proper tube secure

„ Aspiration

„ 30-45% head or bed elevation

„ Monitoring gastric residuals

„ Tube clogging

„ Flush q3-4 hours

ENT Complications

„ Gastrointestinal

„ Non-tube feeding factors

„ Medical condition

„ GI function

„ Medications

„ Failure to feed

„ Tube feeding factors

„ Formula composition

„ Delivery method

„ Contamination

Formula Composition

„ Osmolality

„ Slow infusion rate of hypertonic formula or change to isotonic formula

„ Lactose

„ Use lactose free formula

„ Fiber content

„ Use fiber-containing formula

„ Complexity

„ Change to oligomeric formulas for patients with malabsorption/maldigestion

Continuous Feeding Method of Delivery

„

In continuous feeding, advance full strength formula slowly

„

Starts with rate of 25 mL/hour,

then changes to 50 mL/hour, then

changes to 75 mL/hour

Intermittent Feeding Method of Delivery

„

Initiate at full strength

„

Initiate at small volumes and slow rates (≦ 250 mL/20 min)

„

Progress up to no more than 500 mL/30 min

„

Avoid bolus feeding

„

Administer jejunal feeding

continuously

Prevention of Tube Feeding Contamination

„

Recommended formula hang time

„ Decanted 8-12 hours

„ Commercially pre-filled containers 24 hours

„ Practice clean technique when preparing feeding

Criteria for Determining Patient Eligibility for HNT

„ Willingness to accept therapy

„ Medical suitability

„ Rehabilitation potential

„ Adequate social and economic issues

„ Acceptable home environment

„ Acceptable education, psychological and emotional factors