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| Ques.1 |
What is Nutrition? |
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| Ans: |
Nutrition is a process/science through which all the nutrients, required to maintain the proper metabolic activities within the body, are given in adequate quantity to a person/ patient.The human body needs continuous and regulated supply of nutrients for normal growth, physiological functioning & health maintenance. The main nutrients, utilized for the human body are
1. Carbohydrates
2. Fats (Lipids)
3. Proteins
These are the major elements of the diets. Other minor elements are trace elements, vitamins & minerals. These are metabolized by the cell & produce energy in form of ATP.
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| Ques.2 |
What are Carbohydrates? |
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| Ans: |
The organic molecules,
• Which are made up from the carbon, hydrogen & oxygen
• Having an empirical formula Cn (H2O)n
• Contain polyhydroxy aldehyde or ketone group.
are known as carbohydrates.
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Carbohydrate Metabolism
About 45% of total energy uptake is derived from carbohydrates. Glucose is the most important source of fuel & produces energy.
Diet is first converted in to the simple forms. After metabolism, intestinal wall absorbs them. This is applicable for all types of the complex molecules. Similarly carbohydrates are also converted in to its simple form i.e. glucose. This glucose is taken up by individual cell from the blood. After reaching to the individual cell, glucose enters into the Kreb’s cycle. In this cycle, energy is produced. From this energy, body utilizes the necessary energy & remaining energy is stored. Excess amount of the glucose is converted in to glycogen & stored in the liver.
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Classification |
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Functions
• Major source of energy (4Kcal/gm)
• Effects on satiety and gastric emptying
• Control of blood sugar and insulin metabolism
• Maintain Gastro-intestinal function and integrity
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| Ques.3 |
What are Lipids? |
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| Ans: |
Lipids include fats, oils, and waxes. Molecules classified as lipids are relatively insoluble in water and are soluble in non-polar solvents like ether or chloroform. Dietary lipids have a high-energy content and are important sources of fat-soluble vitamins and essential fatty acids. In cellular structures, lipids form substantial portions of all membranes. Lipids are stored in adipose tissues that act as insulation, both thermal and electrical, and support and cushion internal organs.
Fats are compounds composed of fatty acids bound to glycerol. The side chains or R groups of fatty acids usually contain an even number of carbon atoms in a straight chain. The carbon atoms may be joined by single (saturated) or double bonds (unsaturated).
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Classification of Lipids
3 Fatty acid + 1 glycerol = Triglyceride
Triglyceride is further classified in to following-
LCT
• Chain length - > 12 C
• Rich source of EFA
• Require L-Carnitine to enter inside cell. So take more time to produce energy
MCT
• Chain length – 6-12 C
• Lack of EFA
• Doesn’t require L-Carnitine to enter inside cell, so act as instant source of energy
Fatty acid is further classified in to following:
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Functions
• A source of essential fatty acids
• Most concentrated source of energy
• Reserve energy supply in body
• Carrier for fat soluble vitamins like A, D, E & K
• Synthesizer of important compounds like phospholipids, cholesterol etc.
• Cushion and insulation for body and organs
• Fasten wound healing
• Softness of the skin
• A satiety factor (sense of satisfaction from meals)
• Provides 9 Kcal/ gm
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| Ques.4 |
What are Proteins? |
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| Ans: |
Proteins and peptides are made of amino acids that are joined by covalent bonds called peptide bonds. Some 300 amino acids occur in nature but only 20 of these are relevant to protein synthesis in living things.
Protein is a building block of the body. Basic functional unit of the protein is amino acid; the chemical formula of the protein contains C, H, O, N and/or S.
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Amino acid
Amino acids are the building blocks (sub-units) of proteins. Our daily protein requirement is really a need for amino acids. They contain nitrogen, which is the fourth most abundant element in the body. The amino acids in the body are all "alpha" amino acids, meaning that they have nitrogen attached to the first (alpha) carbon atom in the molecule. The nitrogen also has hydrogen atoms attached to it, thus forming an "amine" group. Hence, it is term "amino" acid.
Amino acids also contain a carboxyl group, as do fatty acids. Carboxyl groups are the basis of carboxylic acid; hence the term "acids" is used for both amino acids and fatty acids. The body can use only amino acids that have the structure that bends light to the left (levo). The letter “L” preceding their names designates these amino acids.
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Classification
Amino acid can be classified in to the following:
Essential amino acid (EAA)
They are the amino acid, which cannot be produced within body so we have to acquire it from the outside i.e., from the food.
There are nine essential amino acids are present in the nature and they are:
- Phenyalanine - Leucine - Methionine
- Isoleucine - Threonine - Tryptophan
- Valine - Arginine - Lysine
Non-essential amino acid (NEAA)
They are the amino acids, which are synthesized in the body. Examples are glutamine, histidine etc. it doesn’t mean that they’re not useful to body but body synthesizes it as and when required.
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Functions:
• Tissue maintenance & repair
• Growth
• Enzymes & hormones synthesis
• Blood proteins
• Fluid balance
• Body proteins
• Immuno-competence
• Energy (4 Kcal/gm)
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Estimate of Protein Requirement
Estimate needs:
Maintenance : 0.8 - 1.0 gm / kg bw/ day.
Mild stress : 1.0 - 1.4 gm / kg bw/ day.
Severe burns : 1.5 - 2.2 gms / kg bw/ day.
Repletion factor = 4 gms / day.1 gm Nitrogen = 6.25 gms of protein.
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Estimate of Energy Requirement
Energy requirements: BEE* x Stress factor x Activity factor
(Activity factor can vary from 0.5 to 1.0 & Stress factor from 0.8 to 2.0)
(* Basal Energy Expenditure)
PROTEIN AND CALORIE REQUIREMENT
| Requirement |
Mild stress |
Moderate stress |
Severe stress |
| Gm / kg / Day |
1.0 |
1.5 |
2-2.2 |
| Kcal / kg / Day |
30 |
35 |
45 |
| Non protein kcal : N2 ratio |
167:1 |
133: 1 |
100 – 125: 1 |
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| Ques.5 |
What is Malnutrition? |
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| Ans: |
A condition caused by inadequate intake or inadequate digestion of nutrients. It may result from eating an inadequate or unbalanced diet, digestive problems, absorption problems, or other medical conditions.
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Types of malnutrition
Malnutrition has two forms:
1) Protein malnutrition (kwashiorkor or hypo-albuminemic malnutrition)
2) Protein-calorie (marasmus or protein-energy) malnutrition.
Protein malnutrition is usually caused by inadequate nutrient intake in conjunction with the stress response. Common causes include chronic diarrhea, renal dysfunction, infection, hemorrhage, trauma, burns, and critical illness. Protein malnutrition can result in:
• Marked hypo-albuminemia
• Anemia
• Edema
• Muscle atrophy
• Delayed wound healing
• Impaired immuno competence
Protein malnutrition is not as easily recognized as protein-calorie malnutrition, but is associated with significant increases in the rates of morbidity and mortality.
The patient with protein-calorie malnutrition is typically emaciated, elderly, and chronically ill. Long-term nutritional repletion is usually required. Protein-calorie malnutrition usually results in:
• Weight loss
• Reduced basal metabolism
• Depletion of subcutaneous fat
• Brady-cardia and Hypothermia
Although the distinction between protein malnutrition and protein-calorie malnutrition is not always clear, these conditions can usually be differentiated on the basis of time course, etiology, and clinical signs.
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Causes for malnutrition:
Medical problems
• Recent surgery or trauma
• Sepsis
• Chronic illness
• Gastrointestinal disorders
• Anorexia, other eating disorders
• Dysphasia
• Recurrent nausea, vomiting, or diarrhea
• Pancreatitis
• Inflammatory bowel disease
• Gastrointestinal fistulas
Psychosocial problems
• Alcoholism, drug addiction
• Poverty, isolation
• Disability
Abnormal diet
• Fad or limited diet
• Recent decrease in food intake
Consequences of malnutrition:
Malnutrition places stressed patients at a greatly increased risk for morbidity and mortality.
Complications include:
• A longer recovery period
• Impaired host defenses and sepsis
• Impaired wound healing
• Anemia
• Impaired GI tract function
• Muscle atrophy
• Impaired cardiac function
• Impaired respiratory function
• Reduced renal function
• Brain dysfunction
• Delayed bone callus formation
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| Ques.6 |
What is Enteral Nutrition? |
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| Ans: |
A complete nutrition, (containing carbohydrates, protein, fat, vitamins and minerals), which is given by the enteral route (tube feed or orally) is known as enteral nutrition.
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Advantages of EN:
Utilizes normal physiological actions of digestion and absorption
• Substrate utilization is more superior in enteral feeding than in parenteral hyper alimentation
• GI integrity is maintained with enteral delivery of nutrients
Safe
• Avoids complications associated with parenteral hyper alimentation, e.g. sepsis, thrombophlebitis, catheter embolus
Convenient
• Does not require sterile technique
• Less monitoring is required
Economic
• Lower cost than parenteral solutions and equipment
Self-medication
• Self-medication is possible in the case of enteral nutrition.
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Routes Of Administration For Enteral Nutrition
Enteral nutrition can be administered by two ways
1) Oral feeding
2) Tube feeding
1) Naso enteric
i) Naso gastric
ii) Naso duodenal
iii) Naso jejunal
2) Enterostomy
i) Placed surgically
(a) Gastrostomy
(b) Jejunostomy
ii) Placed endoscopically
(a) Percutaneous endoscopic Gastrostomy
(b) Percutaneous endoscopic Jejunostomy
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Decision Making Chart For Enteral Nutrition Route
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Enteral tube feeding
Indications:
• Inability to consume adequate nutrients by mouth with gastrointestinal tract that can be used safely
• Severe Dysphagia
• Malnourished patients with pressure ulcers
• Patients who will be unable to consume adequate calories
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| Ques.7 |
What is Parenteral Nutrition? |
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| Ans: |
The provision of "sensible" amounts of nutrients to support the patient until sufficient oral or enteral feeding can be established could be described as the mission statement for TPN therapy.
TPN is an essential feature of the modern medical care. It has been for nearly 15 years now that TPN is being given through TNA (Total Nutrient Admixture) or AIO (All in one) admixture with carbohydrates, lipids, and amino acids mixed in a bag and infused continuously over 24 hours.
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Total Nutrition: Fluid containing all the nutritive elements
The primary goal of Total Parenteral Nutrition (TPN) is to provide patients with adequate calories and protein to prevent malnutrition and its associated complications. A normal diet provides individuals with an adequate mix of carbohydrates, fats and proteins for energy and tissue development.
TPN therapy is a critical element in the treatment of patients. One out of eight persons undergo parenteral nutrition therapy of some or the other form by the means of Total or Partial parenteral nutrition every year.
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Evolution And Advancement of Delivery System:
Parenteral Nutrition and the delivery systems have evolved to a very large extent in the past decade.
Ever since the importance of Nutrition in Clinical Setting has been realized, not only pharmaceutical companies, but to a very large extent even the medical fraternity has contributed a lot to the Evolution and the Advancement of the Parenteral Nutrition products as well as their delivery systems.
From “One-in-One” Glass bottles to “Two-in-One” Double Chamber Bags and now the latest buzzword in Total Parenteral Nutrition “Three-in-One” Triple Chamber bags.
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Routes of Administration:
TPN can be given through:
1. Central route using Central Venous Catheter
2. Peripheral route in case lower osmolarity solution
Complication of The Central Venous Catheterization:
• Catheter related sepsis (Metabolic & Mechanical)
• Venous thrombosis (blockage of the vein by clot formation)
• Entry in to the pleural space
• Arterial / venous injury
• Cardiac injury
• Catheter embolism (blockage of the catheter)
• Extensive catheter care is required
Limitation Of Peripheral Route:
• Concentrated solutions of more than 900 mOsmol / L cannot be used
• The site of the infusion needs to be changed every 24 hours
• Thrombophlebitis, swelling, reddening of site & pain |
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