130

Part II Nutrition Assessment, Consequences, and Implications

TABLE 8.3 Hypertonic Dehydration Lab Test

Osmolality, serum Sodium, serum Albumin BUN

BUN:creatinine ratio Urine-specific gravity

Abbreviation: BUN, blood urea nitrogen.

PREVENTING AND TREATING DEHYDRATION

It is very important to determine the type of dehydra- tion, because treatment depends on correct identifica- tion (20). Preventing dehydration is preferable to treating it. The first step is to estimate fluid needs. A number of equations for estimating fluid needs are available (44,45), but the simplest method is to esti- mate a baseline of 30 mL of water per kilogram of body weight (making sure to provide a minimum of 1,500 to 2,000 mL) and adjust per individual need (24). (See Box 8.4.)

The dietetics practitioner should ensure that the appropriate type of fluid is provided. In cases of evapo- rative fluid loss, water from beverages, food, medical nutritional supplements, tube feedings, or IVs is the appropriate replacement fluid. When GI fluid is lost, however, water and electrolytes must be replaced. An oral rehydration solution (46) or an appropriate IV solution can be used.

Overhydration leading to congestive heart failure is rare, especially when the oral/enteral route is used. However, cardiac and pulmonary monitoring should be done to detect fluid overload in clients with a history of cardiac problems.

Observing the resident during mealtime and collect- ing information from staff involved with daily meals is a useful and inexpensive evaluative tool to aid in avoiding dehydration. All staff, no matter what department or at what professional level, must work together to avoid dehydration. Even housekeeping can be cognizant of urine color in catheter bags when in resident rooms and encourage residents to have a drink.

Being proactive in promoting hydration is the key: ●

Minimize the length of time that residents in nursing facilities have to fast. If it is midnight to 8:00 AM, then staff should provide a late-night snack that has a high fluid content.

●

Work with the consultant pharmacist, nursing service, and physician to discontinue or reduce dosages of medications that may increase the potential for fluid imbalances.

BOX 8.4 Adult Fluid Requirements

Hydration status as a part of nutritional status is often overlooked. This can affect interpretation of biochemical measurements, anthropometry, and the physical exam. Assessment of hydration is quick and easy and should include assessment of fluid intake.

Method I: Wt (kg) × 30 mL = Daily Fluid Requirement Fluid requirements may differ for those clients with cardiac problems, renal failure, or dehydra- tion, or for those requiring fluid restrictions.

Method II: 100 mL/kg for first 10 kg body weight + 50 mL/kg for second 10 kg body weight + 15 mL/kg for remaining kg body weight

Shortcut Method II: [(kg body weight – 20) × 15] + 1,500 = mL fluid requirement

Source: Reprinted with permission from Chidester JC, Spangler AA. Fluid intake in the institutionalized elderly. J Am Diet Assoc. 1997;97:23-28, with permission from American Dietetic Association.

Normal Values

285–295 mOsm/kg water 136–145 mEq/L 3.5–5 g/dL

10–20 mg/dL 10:1

1.005–1.030

Hypertonic Dehydration > 295 mOsm/kg water 145 mEq/L > Normal > Normal > 25:1

> 1.031