Refeeding Syndrome
Refeeding REFEEDING SYNDROME (source: Management of Refeeding Syndrome in Medical Inpatients) Epidemiology 14.6% of 967 malnourished patients Pathophysiology (hypothetical) 1. Decreased insulin, increased glucagon 2. Glycogenolysis -› gluconeogenesis - › protein catabolism; vitamin deficiencies due to reduced intake; lipolysis -› free fatty acids -› ketogenesis in liver. 3. Carbohydrate reintroduction stimulates insulin secretion, anabolic processes. 4. Increased protein synthesis, Na+ retention, glucose uptake, thiamine use, intracellular shift of P04, Mg2+, and K+ 5. Hypophosphate, hypomagnesium, hypokalemia, hypothiamine (beriberi symptoms) , salt/H20 retention Risk Factors --A) Minor risk factors ---BMI < 18.5
›10% unintentional weight loss in 3-6 months
›5 days starvation
h/o EtOH / drug abuse
--B) Major risk factors -=--BMI < 16
›15% unintentional weight loss in 3-6 months
›10 days starvation
LOW K+/P04/Mg2+ prior to feeding
--C) Very high risk factors - - - -BMI < 14
›20% weight loss
---›15 days starvation --1 of A = LOW; 2 of A or 1 of B = HIGH; 1 of C = VERY HIGH Clinical Presentation 1. First 72 hrs after nutritional therapy, regardless of feeding mode 2. Hyperglycemia 3. Electrolyte imbalances: --Hypophosphatemia --<0.32 mmol/L --A central defining criterion in several studies --Rhabdo, hemolysis, respiratory failure -Hypokalemia, Hypomagnesemia
<2.5 mmol/L, <0.50 mmol/L
- -Cardiac ARRHYTHMIA, paresis, rhabdo, confusion, respiratory insufficiency 4. Vit B1 deficiency -Essential coenzyme in Krebs cycle Refeeding --Two weeks causes depletion of stores -Glucose gets converted to lactate instead leading to MET ACIDOSIS -Wernicke's encephalopathy (dry beriberi) -Cardiovascular disorder (wet beriberi) 5. Salt retention -K+ shift intracellularly leads to HYPERNATREMIA (Na+/K+-ATPase) -Water retention - -Noradrenaline/Angiotensin I lead to peripheral resistance and EDEMA 6. Tachycardia 7. Tachypnea Diagnosis -Electrolyte imbalances, either.
Phosphate decreased >30% from baseline or
<0.6 mmol/L -- Two electrolyte shifts below normal range (Mg2+, P04, K+) -Plus clinical symptoms, any of. ---Tachycardia - - Tachypnea --Peripheral edema Management 1. Level of evidence. Very few CTs, systematic review of case series, retrospective, cohort, and case-control studies. National Institute for Health and Care Excellence guidelines are often standard or care. 3. Nutritional support (Friedli et al. 2018 systematic review of 45 studies) --10-15 kcal/kg/day (5 for high risk) [Dog et al 2015 RCT showed low calorie diet was effectivel --50-60% CHO, 30-40% fat, 15-20% protein --20-30 mL/kg/day fluid © fluid balance -Thiamine 200-300 mg IV or PO for 3 days and 10 days multivitamin. 4. Risk stratification = High risk, expert consensus treatment plan --Check K, Mg, P04, Na, Ca -Correct fluid deficit --Correct electrolyte levels prior to feeding - -Supplement vitamins 200% DV, and trace elements 100% DV prior to feeding --Thiamine sould be given at least 30 minutes prior to feeding (see below) --Calories ---Day 1-3: 10-15 kcal/kg/day -Day 4-5: 15-25 kcal/kg/day -Day 6: 25-30 kcak/kg/day -Day 7+: full requirement --Fluids •-Day 1-3: 25-30 ml/kg/day --Day 4+: 30-35 ml/kg/day --Electrolytes
Day 1-7: Na+ restriction, < 1 mmol/kg/day
--Vitamins
Day 1-3: 200-300 mg thiamine
•---Day 1-10: Multivitamin --Check daily body weights and hydration status -Check electrolytes