Specialized Diets and Clinical Nutritional Interventions
Isolation Diet
The Isolation Diet is a monotonous diet, low in bacteria, indicated for patients with immunosuppression or hematologic malignancies. It often leads to suboptimal nutrient intake, aggravated by factors such as prolonged hospital stays, physical isolation, discomfort associated with chemotherapy treatment, and depression. This diet consists of cooked or pasteurized foods with minimal handling during preparation. It strictly excludes raw foods, including vegetables and unpeeled fruits. Commercially processed juices are permitted.
Personalized Diets
Personalized diets are therapeutic diets with specific dietary restrictions, often requiring detailed instructions or comments for preparation due to factors like food allergies, dislikes, or religious considerations. They are prepared daily. Due to their complexity, menu planning for two weeks, as with other diets, is not feasible, nor is their widespread application.
Optional Diets
With an optional diet, patients can choose from several food options daily, typically offering four possibilities for the first course, second course, and dessert. However, indiscriminate use of this option may lead to nutritionally unbalanced diets. Its indication is limited to patients prescribed a basal diet (normal or diabetic) who, due to circumstances like prolonged hospitalization, require special human attention, even at the expense of optimal nutritional quality. Therapeutic diets cannot be made optional.
Artificial Nutritional Support
The term “artificial nutritional support” describes various techniques used when an individual cannot meet their nutrient needs through normal oral food intake. Nutritional support may be needed to replenish lost body mass during simple starvation, but it is most often required to mitigate the effects of metabolic stress that persist for longer than 5-7 days. Methods of nutritional support include:
- Oral supplements: The addition of liquid or solid supplements that the patient swallows.
- Enteral nutrition: Gavage or tube feeding, where nutrients are delivered via a tube placed in the gastrointestinal tract.
- Parenteral nutrition: Nutrient administration directly into the venous system when the digestive tract is not functional or accessible.
Selecting Nutritional Support Methods
Parenteral nutrition, administered via a central vein, can meet all macronutrient needs, bypassing the gastrointestinal tract’s absorption processes. A general guideline for choosing between enteral nutrition (tube feeding) and parenteral (intravenous) nutrition is based on the axiom: “If the gut works, use it.” Using parenteral nutrition when the gut is functional carries greater risks that can be harmful.
Factors for Method Selection:
The decision to use a particular nutritional support method depends on three key factors:
- Presence or absence of a functional bowel
- Practical access to the intestine
- Anticipated duration of nutrition therapy
Additionally, some methods are not mutually exclusive and can be used in combination, particularly during transitions from one method to another.
Enteral Nutrition
Oral Nutritional Supplements
The selection of an oral nutritional supplement depends on several factors:
Factors for Supplement Selection:
- Inability to meet nutritional needs through diet alone
- Presence or absence of dysphagia (difficulty swallowing)
- Taste preference or sensitivity
- Fatigue
- Manpower and resources available to prepare food
- Tolerance to lactose, sucrose, glucose, or other dietary components
- Gastrointestinal tolerance to enteral osmotic load
Enteral Tube Feeding
Enteral tube feeding involves the administration of a liquid formula through a tube.
Indications for Enteral Tube Feeding:
- To meet normal or increased nutritional requirements in patients unable or unwilling to eat, such as those with:
- Anorexia
- Facial trauma
- Disorders of consciousness
- Mechanical ventilation
- Sepsis
- Transition from parenteral to oral nutrition.
Note: Enteral tube feeding requires a functional digestive tract (total or partial capacity).
Nasogastric Tube
The nasogastric tube is the simplest access device for enteral nutrition. It is generally well-tolerated by individuals with normal gastrointestinal function and an intact gag reflex. Its use allows for the normal digestive, hormonal, and bactericidal processes of the stomach to continue.