Chapter 45: Nutrition
Chapter 45: Nutrition
Scientific Knowledge Base
Foundational Components of Nutrition:
Carbohydrates
Proteins
Fats
Water
Vitamins:
Fat-soluble vitamins
Water-soluble vitamins
Minerals
Nutrients:
Definition: The biochemical units of nutrition, comprising essential elements required for bodily functions.
Anatomy and Physiology of the Digestive System
Key Processes:
Digestion: The breakdown of food into smaller components.
Absorption: The process of taking in nutrients from digested food.
Metabolism and Storage of Nutrients: Includes chemical reactions within cells that convert nutrients into energy and store them for future use.
Elimination: The removal of indigestible substances from the body.
Major Organs of the Digestive System
Gallbladder:
Function: Stores and concentrates bile, which is essential for fat digestion.
Liver:
Functions:
Breaks down and builds many biological molecules.
Stores vitamins and iron.
Destroys old blood cells and poisons.
Produces bile to aid in digestion.
Small Intestine:
Functions:
Completes digestion.
Absorbs nutrients and most water.
Mucus protects the gut wall from damage.
Stomach:
Functions:
Stores and churns food.
Hydrochloric acid (HCl) activates enzymes and breaks up food, while also killing germs.
Limited absorption occurs due to the protective mucus lining.
Pancreas:
Functions:
Hormones regulate blood glucose levels.
Produces bicarbonates to neutralize stomach acid for proper enzyme function in the small intestine.
Large Intestine:
Functions:
Reabsorbs some water, ions, and vitamins.
Forms and stores feces for elimination.
Dietary Guidelines
Key Components:
Dietary Reference Intakes (DRIs): Established guidelines of nutrient intake levels.
Food guidelines: Recommendations for food variety and balance.
Daily values: Reference values for nutrient contents in foods to assist in dietary planning.
Nursing Knowledge Base
Factors Influencing Nutrition:
Environmental Factors: Such as access to food and economic barriers.
Developmental Needs: Varies across different life stages including, but not limited to:
Infants through School Age: Need for proper breastfeeding, introduction to solid foods, and appropriate formula.
Adolescents: Increased nutritional demands due to growth and development.
Young and Middle Adults: Nutritional requirements tend to stabilize but can change with lifestyle.
Pregnancy and Lactation: Increased nutrient needs for both maternal and fetal health.
Older Adults: Changes in metabolism and absorption, necessitating a reevaluation of nutrient requirements.
Vegetarian Diets:
Types:
Ovolactovegetarian: Consumes eggs and dairy products.
Lactovegetarian: Consumes dairy products but no eggs.
Vegan: Excludes all animal products.
Alternative Food Patterns: Other dietary practices that may have unique nutritional outcomes.
Nursing Process
Assessment
Key Components of Assessment:
Through the Patient’s Eyes: Understanding the patient’s perspective on their nutrition.
Screening: Identifying nutritional risks.
Anthropometry: Measurement of body metrics (height, weight).
Laboratory and Biochemical Tests: Evaluating nutritional status through biological samples.
Diet History and Health History: Gathering comprehensive dietary intake over time.
Environment: Assessment of home and community resources.
Physical Examination: Observing signs of malnutrition or dietary deficiencies.
Dysphagia: Assessment for swallowing difficulties which can impact nutritional intake.
Analysis and Nursing Diagnosis
Common Diagnoses Include:
Risk for Aspiration: Concerns over food or fluids entering the airway.
Overweight: Excessive body weight relative to height and age.
Impaired Low Nutritional Intake: Inability to meet nutritional requirements.
Impaired Self-Feeding: Difficulties with feeding oneself.
Impaired Swallowing: Physical issues related to the intake of food.
Planning and Outcomes Identification
Key Considerations:
Outcomes: Establish desired nutritional outcomes based on assessments.
Setting Priorities: Determining which nutritional needs must be addressed first.
Teamwork and Collaboration: Working with a multidisciplinary team for optimal patient care.
Implementation
Strategies for Implementation:
Health Promotion: Activities to encourage healthy eating and active lifestyle.
Acute Care: Nutritional interventions during hospitalization.
Advancing Diets: Gradually transitioning patients through different diet stages as their condition improves.
Promoting Appetite: Techniques to enhance patient food intake.
Assisting Patients with Oral Feeding: Ensuring safety and comfort during meals.
Enteral Tube Feeding:
Types:
Levin Tube: A flexible tube used for feeding.
Weighted Feeding Tube: Designed to aid in placement within the stomach.
Salem Sump Tube: A double-lumen tube for gastric decompression and feeding.
Parenteral Nutrition
Implementation Tasks:
Initiating Parenteral Nutrition: Guidelines for starting intravenous nutritional support.
Preventing Complications: Strategies to minimize risks associated with parenteral nutrition.
Blood Glucose Monitoring: Regular checks to maintain safe blood sugar levels during feeding.
Restorative and Continuing Care
Considerations in Restorative Nutrition:
Medical Nutrition Therapy:
Used for managing various diseases, including:
Gastrointestinal Diseases
Diabetes Mellitus
Cardiovascular Diseases
Cancer and Cancer Treatment
HIV/AIDS
Evaluation
Assessment of Outcomes:
Through the Patient’s Eyes: Evaluating patient satisfaction with nutritional outcomes.
Patient Outcomes Measurement: Assessing the efficacy of interventions.
Safety Guidelines for Nursing Skills
Precautions during Nursing Procedures:
Anticoagulation and Bleeding Disorders: Risk of epistaxis during nasal tube placement.
Risks Associated with Nasal Tubes: Including sinusitis, otitis, vocal cord paralysis, and pressure injuries.
Use of ENFit Connectors: Requirement for enteral nutrition sets to promote safety and compatibility.
Aseptic Technique: Essential for preparing and delivering enteral feedings.
Labeling Enteral Equipment: To ensure correctness and avoid mix-ups.
References
Copyright ©2026 by Elsevier, Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Chapter 45: Nutrition
Scientific Knowledge Base
Foundational Components of Nutrition:
Nutrients:
Definition: The biochemical units of nutrition, comprising essential elements required for multiple body functions. They are necessary for us to meet all our energy needs.
Carbohydrates:
Main source of energy in the diet and fuel for the brain, skeletal muscles during exercise, erythrocyte and leukocyte production, and cell function of the renal medulla.
Primary source: plant-based foods (except for lactose).
Fiber: Structural part of plants not broken down by digestive enzymes. Can be soluble or insoluble.
Proteins: Essential for the growth, maintenance, and repair of body tissues.
Fats (Lipids):
Most caloric-dense nutrients.
Composed of triglycerides and fatty acids.
Water:
Utilized to maintain an adequate fluid environment.
Makes up 60 to 70% of the total body weight.
Adequate intake comes from drinking liquids and eating solid foods with high water content (e.g., fresh fruits and vegetables).
Vitamins:
Essential to normal metabolism.
Fat-soluble vitamins: A, D, E, and K.
Water-soluble vitamins: C and B complex.
Minerals: Inorganic elements essential to the body to stimulate biochemical reactions.
Anatomy and Physiology of the Digestive System
Key Processes: Make sure to review the Anatomy and Physiology (A&P) of the digestive system as it relates to these processes (as illustrated in figure 45.1 in the book):
Digestion: The breakdown of food into smaller components, beginning with food particles in the mouth and lubrication by salivary glands.
Absorption: The process of taking in nutrients from digested food.
Metabolism and Storage of Nutrients: Includes chemical reactions within cells that convert nutrients into energy and store them for future use.
Elimination: The removal of indigestible substances from the body.
Major Organs of the Digestive System
General Flow: Food is swallowed down the pharynx and transported by the esophagus into the stomach, gallbladder, liver, and pancreas area, eventually proceeding to the rectum and anus for elimination.
Gallbladder:
Function: Stores and concentrates bile, which is essential for fat digestion.
Liver:
Functions:
Breaks down and builds many biological molecules.
Stores vitamins and iron.
Destroys old blood cells and poisons.
Produces bile to aid in digestion.
Small Intestine:
Functions:
Completes digestion.
Absorbs nutrients and most water.
Mucus protects the gut wall from damage.
Stomach:
Functions:
Stores and churns food; churning action begins here.
Hydrochloric acid (HCl) activates enzymes and breaks up food, while also killing germs.
Limited absorption occurs due to the protective mucus lining.
Pancreas:
Functions:
Hormones regulate blood glucose levels.
Produces bicarbonates to neutralize stomach acid for proper enzyme function in the small intestine.
Large Intestine:
Functions:
Reabsorbs some water, ions, and vitamins.
Forms and stores feces for elimination.
Dietary Guidelines
MyPlate Program:
Developed by the USDA, replacing the My Food Pyramid chart.
Provides a basic guide for making food choices for a healthier lifestyle.
MyPlate Electronic Application: Allows individuals to receive personalized food choices and track progress in real-time.
Key guidelines and recommendations for the general population can be found in Box 45.2 of the book.
Dietary Reference Intakes (DRIs):
Established guidelines of nutrient intake levels that present evidence-based criteria for an acceptable range of amounts of vitamins and nutrients for each gender and age group.
Nutrient and vitamin requirements are based on age, height, and weight.
Food Guidelines:
Recommendations for food variety and balance, including 4 major components: fruits, vegetables, grains, and protein.
Guidelines are updated and revised on a yearly basis (e.g., Dietary Guidelines for Americans 2020-2025).
Daily Values: Reference values for nutrient contents in foods to assist in dietary planning.
Adequate Diet: Includes guides for balancing calories, decreasing portion size, increasing healthy food choices, increasing water consumption, and decreasing fat, sodium, and sugars.
Nursing Knowledge Base
Factors Influencing Nutrition:
Individual caloric and nutrient requirements vary by:
Stage of development
Body composition
Activity levels
Pregnancy and lactation
Presence of diseases
Environmental Factors: Beyond individual control, contributing to conditions like obesity.
Lack of access to full-service grocery stores or affordable healthy food choices (e.g., food deserts).
Developmental Needs: Varies across different life stages including, but not limited to:
Infants through School Age:
Marked by rapid growth and high protein, vitamin, mineral, and energy requirements.
Energy intake for healthy infants (birth to 1 year): approximately . Neonates need .
Nutritional needs of premature infants vary with gestational age and stage of growth.
Breastfeeding: Recommended for newborns for the first 6 months of life and with complementary foods from 6 months to 2 years.
Benefits: decreased ear infections, lower respiratory illness, sudden infant death syndrome (SIDS), childhood leukemia, decreased diabetes, obesity, asthma, and atopic dermatitis. It's also economically beneficial.
Formula: Iron-fortified formulas are acceptable for infants if breastfeeding is not chosen, with nutrient composition approximate to human milk.
Infants should not have regular cow milk during the first year of life as it is too concentrated for the infant's kidneys.
Breast milk or formula provides sufficient nutrients for the first 4 to 6 months.
Introduction of Solid Food: Iron-fortified cereals are typically the first semi-solid food (4 to 11 months) and are an important non-milk source of protein. Foods are added based on the infant's nutritional needs, physical readiness, and need to detect/control allergic reactions.
Adolescents:
Increased energy needs to meet greater metabolic demands for growth.
Risks: high consumption of fast food, obesity, concerns about body image, desire for independence (eating at fast food restaurants), peer pressure, and fad diets (e.g., anorexia nervosa, bulimia nervosa).
Young and Middle Adults:
Need nutrients for energy, maintenance, and repair.
Energy needs usually decline over the years; obesity becomes a problem due to decreased physical exercise, eating out more often, and increased ability to afford more luxury foods.
Adult women using oral contraceptives often need extra vitamins.
Iron and calcium intake continue to be important for bone density.
Pregnancy and Lactation:
Increased nutrient needs for both maternal and fetal health.
Older Adults:
Adults 65 years and older have a decreased need for energy as metabolic rates slow with age.
Vitamin and mineral requirements remain unchanged compared to middle adulthood.
Religious and Cultural Dietary Restrictions:
Many people follow special dietary recommendations and restrictions based on religious beliefs, cultural background, health beliefs, personal preference, or concern for efficient land use to produce food.
Table 45.3 in the book provides detailed examples of religious dietary restrictions (e.g., Muslim, Christianity, Hinduism, Judaism, Churches of Jesus of Latter-day Saints/Mormons, Seventh-Day Adventists). Nurses must be familiar with these to accommodate patients' rights and hospital obligations.
Vegetarian Diets: Consumption of a diet consisting predominantly of plant foods.
Types:
Ovolactovegetarian: Avoids meat, fish, and poultry but consumes eggs and milk.
Lactovegetarian: Consumes dairy products but no eggs.
Vegan: Excludes all animal products.
Children following vegetarian diets: Are at risk for protein and vitamin deficiencies (e.g., Vitamin B12), requiring careful planning for a balanced healthy diet.
Alternative Food Patterns: Other dietary practices that may have unique nutritional outcomes.
Nursing Process
Assessment
Key Components of Assessment: Nurses should conduct a complete head-to-toe physical assessment, thoroughly assess each patient, critically analyze findings, and identify accurate nursing diagnoses. Keep close contact with patients and families to identify potential malnutrition or dietary habit problems. Observe for weight changes, cultural eating practices, food preferences, values, and expectations for nutritional therapy.
Through the Patient’s Eyes: Understanding the patient’s perspective on their nutrition.
Screening: Identifying nutritional risks (malnutrition, obesity) early for effective intervention and prevention. This includes obtaining weight and height during admission, comparing to previous admissions, and assessing dietary intake (e.g., regular, low sodium, diabetic, fluid restriction). Screen for malnutrition when conditions interfere with ingesting, digesting, or absorbing adequate nutrients.
Anthropometry: Symptomatic measurement of the size and makeup of the body.
Document actual weight and compare height and weight with standards.
Ideal Body Weight (IBW): Provides an estimate of what a patient should weigh.
Rapid weight gain or loss usually reflects fluid shift.
Body Mass Index (BMI): Measures weight corrected for height and serves as an alternative to traditional height and weight relationships; calculated by dividing a patient's weight in kilograms by height in meters squared ().
Laboratory and Biochemical Tests: Evaluating nutritional status through biological samples.
Common tests: measurement of plasma proteins (albumin, pre-albumin, transferrin, retinol binding proteins, total iron binding capacity) and hemoglobin.
Diet History and Health History: Gathering comprehensive dietary intake over time, focusing on specific diet history. Assess patient's knowledge about any prescribed therapeutic diet (e.g., fluid restriction for renal patients, low-sodium diet) and general nutritional habits.
Environment: Assessment of home and community resources, including access to grocery stores (food deserts), financial ability to purchase food, or reliance on food banks.
Physical Examination: Observing clinical signs of alteration in nutritional status (refer to Table 45.4 in the book for detailed background).
General appearance (fatigue, falling asleep, irritability, confusion, malnutrition), posture, skin turgor.
GI symptoms (diarrhea, constipation, distended abdomen).
Skin (dry and scaly), hair (brittle), lips (dry and flaky), gums (lack of moisture) are key indicators of malnutrition or nutritional deficit.
Dysphagia: Assessment for swallowing difficulties, referring to a sensation of food or liquid being delayed or hindered in passage from mouth to stomach.
Notable in patients with stroke, myasthenia gravis, multiple sclerosis (MS), or due to the aging process.
Risks: aspiration pneumonia, malnutrition, dehydration, increased hospital stay, and readmissions.
Analysis and Nursing Diagnosis
Common Diagnoses Include: Appropriate nursing diagnoses based on assessment findings.
Risk for Aspiration: Concerns over food or fluids entering the airway.
Risk for Malnutrition: Not properly getting the amount of nutrients needed for an adequate diet.
Overweight: Excessive body weight relative to height and age; can also include Risk for Obesity.
Impaired Low Nutritional Intake: Inability to meet nutritional requirements.
Impaired Self-Feeding: Difficulties with feeding oneself (e.g., infants, adults with disease processes).
Impaired Swallowing: Physical issues related to the intake of food (e.g., post-stroke, MS).
Planning and Outcomes Identification
Key Considerations: Develop a plan of care for each identified nursing diagnosis, planning to maintain optimal nutritional status rather than just correcting day-to-day problems. Apply critical thinking and judgment when developing the plan.
Outcomes: Establish desired nutritional outcomes. Consider what behaviors or physical changes would most benefit the patient due to interventions. For improved knowledge, nutritional education and counseling are important, tailored to the patient's understanding for recall and compliance in preventing disease and promoting health.
Setting Priorities: Determine which nutritional needs must be addressed first by considering the urgency, likelihood, and seriousness of identified problems.
Teamwork and Collaboration: Working with a multidisciplinary team for optimal patient care. The plan of care must be carried out 24/7 by all involved (nurse, tech, physician, physical therapy, occupational therapy). Nutritional interventions must be included in discharge planning as patients return home or to extended care settings. Communication of patient outcomes and planned interventions to all team members is essential.
Implementation
Strategies for Implementation:
Health Promotion: Activities to encourage healthy eating and active lifestyle. Nurses play a key role in educating patients and family caregivers about balanced nutrition, healthy food choices, and how to obtain resources. This involves confirming health literacy and providing information about community resources to integrate knowledge into lifestyles and prevent disease or complications.
Acute Care: Nutritional interventions during hospitalization require considering various factors influencing nutritional intake (e.g., NPO status due to testing, non-working feeding tubes).
Patients with nutritional deficits typically require strict intake and output (I&O).
NPO patients typically receive standard IV fluids to replace lost nutrients.
Advancing Diets: Gradually transitioning patients through different diet stages as their condition improves. Often advanced 'diet as tolerated' after NPO, especially for GI disturbances. Special diets may be required for patients with decreased immune function (e.g., neutropenic diet for chemotherapy patients, disallowing fresh fruits or vegetables). Nurses must be astute to these dietary restrictions.
Promoting Appetite: Techniques to enhance patient food intake.
Provide an environment free of odors, offer oral hygiene, and maintain patient comfort.
Offer small, frequent meals.
Medications like megestrol may be prescribed to increase appetite (typically after other measures, for chronic diseases or cancer diagnosis).
Assisting Patients with Oral Feeding: Ensuring safety, independence, and dignity during meals.
Patients with dysphagia are at risk for aspiration and require more assistance: feed slowly, provide smaller bites and sips of water, and allow adequate time to chew thoroughly and swallow before the next bite.
Enteral Tube Feeding: Receiving formula via nasal-internal routes (nasogastric, nasoduodenal, nasojejunal) or through a gastric tube inserted into the stomach (gastrostomy, jejunostomy).
Types:
Routes: Nasogastric, nasoduodenal, nasojejunal, gastrostomy, jejunostomy.
Levin Tube: A flexible tube used for feeding, typically placed by advanced practice nurses (APN) or healthcare providers (HCP).
Weighted Feeding Tube: Designed to aid in placement within the stomach, typically placed by APN or HCP.
Salem Sump Tube: A double-lumen tube for gastric decompression and feeding, which a bedside nurse can insert.
Placement Verification: After insertion, verify tube placement by X-ray before any feeding begins.
Feeding Type: Gastric feeding is for low gastric reflux risk; jejunostomy (or
gegen feeding) is preferred for gastric reflux risk to prevent aspiration.Patient Care Plan: Should include tube maintenance, tolerance to feeding, type of tube placed, GI assessment, and nutritional status.
Safety: Always elevate the head of the bed to a minimal of 30 to 45 degree angle before infusing formula. Test tubes for patency. Maintain aspiration precautions (post signs above the bed if high risk). Maintain adequate intake and output.
Parenteral Nutrition
Implementation Tasks: A form of specialized nutritional support provided via IV, typically through a central line due to the high concentration of nutrients (also known as hyperalimentation/hyperal and lipids).
Initiating Parenteral Nutrition: Guidelines for starting intravenous nutritional support.
Candidates: Patients in highly stressed physiological states such as sepsis, burns, cancer, or head injury.
Preventing Complications: Strategies to minimize risks associated with parenteral nutrition.
Blood Glucose Monitoring: Regular checks to maintain safe blood sugar levels during feeding.
Clinical and laboratory monitoring by the healthcare provider team daily, with orders adjusted based on results (e.g., including glucose for diabetic patients, with ongoing accu-checks).
Registered dietitians also follow these patients daily and recommend adjustments to nutrients.
Restorative and Continuing Care
Considerations in Restorative Nutrition:
Medical Nutrition Therapy: The use of specific nutritional therapies to treat an illness, injury, or condition.
Helps the body metabolize certain nutrients, correct nutritional deficiencies, and eliminate foods that may exacerbate disease symptoms.
Most effective using a team approach that promotes collaboration between the healthcare team and the registered dietitian.
Used for managing various diseases, including:
Gastrointestinal Diseases:
Treatment of malabsorption syndromes like celiac disease includes a gluten-free diet (avoiding wheat, rye, and barley).
Short bowel syndrome results from extensive bowel resection, causing malabsorption due to lack of intestinal surface area, requiring lifetime feeding with elemental enteral formulas or parenteral nutritional feeding.
Diabetes Mellitus:
Type 1 diabetes requires both insulin and dietary management for optimal control from diagnosis.
Type 2 diabetes is often controlled with diet and exercise, monitored by a registered dietitian for adequate nutrients and glycemic control.
Individualized diet according to a patient's age, build, weight, and activity level; maintaining prescribed carbohydrate intake is important.
Cardiovascular Diseases:
Diet therapy aims to reduce risk factors for hypertension and coronary artery disease.
Involves balancing caloric intake with exercise to maintain a healthy body weight.
Eating a diet high in fruits, vegetables, whole grains, and high-fiber foods.
Eating fish at least 2 times per week.
Limiting food and beverages high in added sugar and salt.
Recommended guidelines: limiting saturated fats to less than 7%, trans fats to less than 1%, and cholesterol to less than 300 mg per day.
Cancer and Cancer Treatment:
Due to smell aversion, nausea, and vomiting, creative meal preparation is needed to control odors.
Encourage small, frequent meals and nutritious, easy-to-digest snacks.
Avoid spices due to weak, dry, or brittle gums from chemotherapy or radiation.
HIV/AIDS:
Restorative care for malnutrition focuses on maximizing calories and nutrients.
Address each cause of nutritional depletion in the care plan.
Progression of individualized tailored nutritional support begins with oral nutrition, then progresses to enteral nutrition, and finally to parenteral nutrition.
Evaluation
Assessment of Outcomes: Nurses must evaluate interventions frequently and make adjustments as needed to obtain the best ultimate outcome for the patient. Always include patients in any adjustments to maintain compliance.
Through the Patient’s Eyes: Evaluating patient satisfaction with nutritional outcomes.
Patient Outcomes Measurement: Assessing the efficacy of interventions to maintain adequate nutritional support and well-being.
Safety Guidelines for Nursing Skills
Precautions during Nursing Procedures:
Anticoagulation and Bleeding Disorders: Poses a risk for epistaxis (nosebleeds) during nasal tube placement.
Risks Associated with Nasal Tubes: Including sinusitis, otitis, vocal cord paralysis, and medical device-related pressure injury to the nose.
Use of ENFit Connectors: Required for all enteral nutrient sets, syringes, and feeding tubes to promote safety and compatibility.
Aseptic Technique: Essential for preparing and delivering enteral feedings.
Labeling Enteral Equipment: Always label any type of enteral equipment when utilizing with patients and their feeding, to ensure correctness and avoid mix-ups.
References
Copyright ©2026 by Elsevier, Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.