Protein and Energy Requirements for Dialysis Patients Flashcards

For a patient on nocturnal home hemodialysis (NHHD, 6 nights/week, 8 hours/night), how do dietary restrictions generally compare to conventional HD (3×/week)?

Answer: NHHD patients may have liberalized dietary restrictions (especially for potassium and phosphorus) due to the superior dialysis efficiency of more frequent, longer sessions

Nocturnal home HD (6×/week, 8 hr/night) provides ~3× the dialysis dose of conventional HD, significantly enhancing clearance of small solutes (urea, potassium, phosphorus). This often allows liberalization of dietary restrictions — many NHHD patients can follow a less restrictive diet.

Which validated formula is used to estimate protein and energy needs when indirect calorimetry is unavailable in a hospitalized dialysis patient?

Answer: Modified Harris-Benedict or Mifflin-St Jeor equation adjusted to IBW or dry weight, with a stress factor of 1.0–1.3 depending on clinical status

Predictive equations (Modified Harris-Benedict, Mifflin-St Jeor) using adjusted/ideal body weight provide reasonable energy estimates when indirect calorimetry is unavailable. Stress factors (1.0–1.3) account for clinical condition (stable, mild infection, severe illness).

In a malnourished hemodialysis patient who has been started on aggressive protein and energy repletion, which potentially fatal electrolyte complication must be closely monitored?

Answer: Refeeding syndrome: hypophosphatemia, hypokalemia, and hypomagnesemia from cellular uptake during anabolism

Refeeding syndrome occurs when aggressive nutrition is provided to severely malnourished patients. Insulin released in response to carbohydrate causes intracellular uptake of phosphate, potassium, and magnesium, leading to life-threatening hypophosphatemia (< 1.0 mg/dL), hypokalemia, and hypomagnesemia.

A stable PD patient reports consuming approximately 1.8 g protein/kg/day but has a decreasing serum albumin trend. The MOST likely explanation combining assessment and physiology is:

Answer: Despite adequate protein intake, elevated C-reactive protein (inflammation marker) suggests the albumin decline is inflammation-mediated, not nutritional insufficiency; further investigation of infection or inflammatory condition is needed

Albumin is a negative acute-phase reactant — inflammation suppresses hepatic albumin synthesis regardless of protein intake. In a patient consuming adequate protein but with declining albumin, inflammatory workup (CRP, ESR, cultures for silent peritonitis) is the priority over further dietary protein increase.

Which type of muscle measurement provides the MOST objective assessment of somatic protein stores independent of fluid status in hemodialysis patients?

Answer: Total body protein by neutron activation analysis (NAA)

Total body protein measured by in vivo neutron activation analysis (NAA) is the gold standard for measuring somatic protein stores, but it is research-only. In clinical practice, MAMC (derived from mid-arm circumference and triceps skinfold) is the most accessible and valid fluid-independent muscle measure.

For a hemodialysis patient receiving 3× weekly treatment, what is the optimal timing for the largest protein/meal intake relative to the HD session?

Answer: After dialysis sessions (within 1–2 hours) to replenish amino acid losses and take advantage of post-dialysis anabolic window

Post-dialysis is the optimal time for protein-rich meals because: (1) it replaces the 6–8 g amino acids lost in dialysate; (2) the dialysis session creates an acute catabolic state, and the immediate post-dialysis window (similar to post-exercise) is anabolically primed for protein synthesis.