Page 594 - Nutrition Essentials for Nursing Practice

582 U N I T 3 Nutrition in Clinical Practice

Table 21.7 Nutrition Guidelines for Acute Kidney Injury

Nutrient Recommendations Factors That Impact Actual Allowance

Protein 1.5–2.5 g/kg Degree of catabolism
Renal function
Calories 25–50 cal/kg Approximate amino acid loss during
Sodium 1.1–3.3 g/day
CRRT is 10–15 g/day.
Potassium 2.0–3.0 g/day
Phosphorus Individualized Degree of stress
Calcium Individualized Nutritional status
Fluid 500 mL ϩ urine output
Serum sodium levels
Blood pressure
Edema
Urinary losses (in diuretic phase)
Use of dialysis

Serum potassium levels
Urinary losses (in diuretic phase)

Serum phosphorus levels

Serum calcium levels

Urine output
Type of dialysis, if any

Source: Academy of Nutrition and Dietetics. (2012). Nutrition prescription for acute renal failure. In Nutrition
care manual. Available at www.nutritioncaremanual.com. Accessed on 711/12; and McClave, S., Marteindale,
R., Vanek, V., McCarthy, M., Roberts, P., Taylor, B., . . . Cresci, G. (2009). Guidelines for the provision and
assessment of nutrition support therapy in the adult critically ill patient: Society of Critical Care Medicine
(SCCM) and American Society for Parenteral and Enteral Nutrition (ASPEN). Journal of Parenteral and Enteral
Nutrition, 33, 277–316.

a means to avoid or delay initiation of dialysis therapy (McClave et al., 2009). Serum levels
of potassium, magnesium, phosphorus, and calcium are monitored. Table 21.7 summarizes
nutrient recommendations and factors that influence nutrient needs.

KIDNEY STONES

Hyperoxaluria: ele- Kidney stones form when insoluble crystals precipitate out of urine. They vary in size from
vated levels of oxalate sand-like “gravel” to large, branching stones, and although they form most often in the
in the urine. kidney, they can occur anywhere in the urinary system.

Struvite: magnesium Approximately 75% of kidney stones are made of calcium oxalate; hyperoxaluria is con-
ammonium phosphate sidered to be a primary risk factor for this type of stone (Liebman and Al-Wahsh, 2011). The
crystals formed by the remaining stones are composed of calcium phosphate, uric acid, or struvite. Cystine (an amino
action of bacterial acid) stones are rare and occur only in people with cystinuria, an autosomal recessive disorder.
enzymes.
Certain factors increase the risk of kidney stones, including dehydration or low urine
Oxalate: a salt of volume, urinary tract obstruction, gout, chronic inflammation of the bowel, and intestinal
oxalic acid. Oxalate can bypass or ostomy surgery. A wide variety of dietary factors either promote or inhibit the
form strong bonds with formation of calcium oxalate kidney stones.
various minerals; when
combined with calcium, Fluid. A low fluid intake concentrates the urine, increasing the likelihood of chemicals
it forms a nearly precipitating out to form kidney stones—regardless of the composition of the stone. An
insoluble compound. adequate fluid intake helps keep urine dilute.

Oxalate. Oxalate is found in many plant foods, including nuts, fruit, vegetables, grains, and
legumes. Normally, only 2% to 15% of oxalate consumed is absorbed (Liebman and