1.4 Nutrition Support & Hydration

Key Takeaways

  • Enteral nutrition delivers formula into a functioning GI tract through a feeding tube; parenteral nutrition delivers nutrients intravenously when the gut cannot be used
  • The guiding principle is "if the gut works, use it" — enteral feeding is preferred over parenteral when the GI tract is functional
  • Tube feedings require monitoring of formula type, rate, water flushes, and aspiration precautions such as keeping the head of bed elevated
  • Signs of dehydration include dark urine, dry mouth, decreased intake, confusion, and sudden weakness; older adults are especially vulnerable
  • CMS significant weight loss thresholds are 5% in 30 days, 7.5% in 90 days, and 10% in 180 days
Last updated: June 2026

When a resident cannot meet needs by mouth, the care team turns to nutrition support. The CDM must understand the two routes, support safe tube-feeding operations, and watch for the hydration and weight problems that dominate long-term-care nutrition.

Enteral vs. Parenteral Nutrition

This is the single most confused pair in the domain, so fix it permanently.

Enteral NutritionParenteral Nutrition
RouteFeeding tube into the GI tractIntravenous (IV) into the bloodstream
RequiresA working gutUsed when the gut cannot be used
ExamplesNG tube, PEG/G-tubeTPN (total parenteral nutrition)
PreferencePreferred routeLast resort

The memory hook is "if the gut works, use it." Enteral feeding keeps the digestive tract active, costs less, and carries fewer infection risks than parenteral, so it is preferred whenever the GI tract is functional. Enteral = enters the gut; parenteral = bypasses the gut.

Tube-Feeding Basics

For enteral feeding, the team monitors:

  • Formula type and concentration ordered by the provider
  • Rate and method (continuous pump, intermittent, or bolus)
  • Water flushes to maintain hydration and keep the tube patent
  • Aspiration precautions — keep the head of bed elevated (about 30-45 degrees) during and after feeding

The CDM helps ensure the correct formula reaches the right resident and that supplies and storage meet food-safety standards.

Dehydration: Signs and Strategies

Older adults have a blunted thirst response, making dehydration the most common fluid problem in long-term care. Watch for:

  • Dark, concentrated urine and decreased output
  • Dry mouth, dry skin, poor skin turgor
  • Confusion, weakness, or sudden functional decline
  • Decreased fluid intake at meals

Hydration strategies include offering fluids frequently, providing preferred beverages, hydration carts and pass rounds, fluids with medications, and high-water foods. Dehydration raises the risk of urinary tract infections, falls, and confusion.

Unintended Weight Loss Thresholds

Unintended weight loss is a major clinical red flag and a focus of regulatory surveys. CMS defines significant weight loss by these thresholds:

Time periodSignificant loss
30 days (1 month)5%
90 days (3 months)7.5%
180 days (6 months)10%

Reaching any threshold should trigger nutrition intervention. In practice, the facility should not wait for a deadline — a noticeable downward trend warrants prompt assessment, provider notification, and a documented plan.

Test Your Knowledge

A resident has a fully functioning GI tract but can no longer eat enough by mouth after a stroke. Which form of nutrition support is preferred?

A
B
C
D
Test Your Knowledge

A long-term-care resident weighed 200 lb and now weighs 185 lb one month later. Does this meet the CMS threshold for significant weight loss?

A
B
C
D
Test Your Knowledge

Which finding is MOST consistent with dehydration in an older resident, and why are older adults especially at risk?

A
B
C
D