Nutrient Absorption & Intestinal Surgery Effects

### Nutrient Absorption and Consequences of Intestinal Surgery

• The majority of nutrient absorption occurs in the first half of the small intestine
• The duodenum/jejunum is responsible for absorbing simple carbohydrates, fats, amino acids, vitamins, minerals, and water
• Resecting the duodenum can lead to calcium and iron malabsorption
• The ileum absorbs bile salts, vitamin B12, water, and some carbohydrates, proteins, calcium, magnesium, and phosphorus
• Resecting the ileum can lead to fat and protein malabsorption, vitamin B12 deficiency, and electrolyte imbalances, ultimately resulting in fluid and electrolyte losses, diarrhea, and steatorrhea
• The colon absorbs water, electrolytes, and short-chain fatty acids
• Resecting the colon in addition to the ileum will compound fluid and electrolyte losses and increase diarrhea

### Post-Operative Diet

• A patient recovering from surgery may begin with a diet of nothing by mouth (NPO) to prevent aspiration
• The diet will gradually progress from clear liquids to normal foods as the patient's ability to digest food improves
• Patients may require tube feeding or total parenteral nutrition (TPN) if they are unable to meet their energy requirements through oral intake

### Specific Surgical Conditions

• Colostomy is a surgical procedure that creates an opening from the colon to the surface of the skin to allow for defecation when feces cannot pass through the rectum and anus
• Ileostomy bypasses the entire colon and creates an opening from the ileum to the anus
• Jejunoileostomy involves connecting a short segment of the jejunum to the terminal ileum, effectively bypassing 90% of the small bowel
• Tonsillectomy is the surgical removal of the tonsils
• Cholecystectomy is the surgical removal of the gallbladder
• Hemorrhoidectomy is the surgical removal of hemorrhoids

### Dietary Management

• A cold liquid diet is recommended for tooth extraction, tonsillectomy, and other procedures to prevent bleeding
• Gastrostomy feeding is used to rest the esophagus after removal
• A low-fiber, dry meal diet with restricted carbohydrates is recommended to avoid dumping syndrome
• A high-protein diet with no simple sugars is recommended for gastric surgery

### Dumping Syndrome

• Dumping syndrome is characterized by a decrease in plasma volume due to increased peristaltic movement

### Nutrition Therapy in Burns

• Burns are injured tissue caused by heat, flame, chemicals, electricity, or radiation
• Burns can result in decreased blood volume, plasma loss, edema, damaged vessel walls, increased metabolic rate, weight loss, nitrogen and nutrient losses, and hyperglycemia.

### Metabolic Changes

• Burns cause a loss of tissue which leads to dehydration and fluid imbalances, both intracellularly and extracellularly.
• Loss of protein, salt, and fluid can occur, leading to electrolyte and fluid imbalances, decreased vascular volume and pressure, and decreased urinary output
• Energy expenditure is increased significantly in patients with major burns, exceeding basal needs by 50-100%.
• Edema usually presents within the first 1-2 days after the burn.
• Gastric atony can occur, resulting in delayed gastric emptying
• Patients are at high risk of weight loss.
• Cellular potassium withdrawal is increased, leading to increased serum potassium levels.

### Burn Classification

• First-degree burns affect the epidermis and present as warmth, tenderness, and pain.
• Second-degree burns affect the epidermis and dermis.
• Third-degree burns affect the epidermis, dermis, and subcutaneous fat.

Burn Management

• Medical Management involves pain relievers, anti-infective drugs, and medications to promote tissue regeneration
• Dietary Management begins with IV fluids to replace fluid losses.
• Tube feeding is used to meet energy requirements when oral intake is not possible.
• Fluid and sodium intake is closely monitored to control water retention.
• Providing high-calorie, high-carbohydrate, and high-protein diets are essential to meet increased energy demands, spare protein, and promote tissue regeneration.
• Supplementation with vitamins (vitamin C and B complex) and minerals are crucial for energy metabolism, wound healing, tissue regeneration, and to support oxidative enzyme systems to metabolize extra carbohydrates and proteins
• Iron supplements are recommended to prevent or correct anemia.