Malnutrition & Nutrition Support Flashcards
Aetiology of Malnutrition
Chronic Disease (e.g., organ failure, cancer, sarcopenic obesity):
Decreased appetite, impaired nutrient absorption, increased requirements, metabolic disturbances.
Chronic inflammation → muscle wasting and anorexia.
Acute Disease (e.g., burns, surgery):
Increased metabolic demands, nutrient loss, catabolic processes.
Elevated inflammatory markers due to tissue damage.
Chronic Starvation/Anorexia Nervosa:
Consistent kcal deficiency; may lack inflammatory markers or show low WBC counts.
Acute Muscle Wasting:
Indicated by low pre-albumin or creatinine; linked to trauma, infections, critical illness.
Increased inflammatory markers often present.
Follow-Up Times for Malnutrition
Acute Care Facilities (ACF):
Initial assessment on admission → follow-up weekly until stable.
Monthly follow-up for less critical patients; bi-weekly for high-risk cases.
Community Settings:
Follow-up every 3 months.
Re-Screening in ACF:
Monthly intervals for all patients.
Iatrogenic Malnutrition
Definition: Malnutrition caused by medical treatment or hospital stays.
Causes:
Medications: Side effects like nausea, taste changes, poor appetite.
Neglect: Lack of nutritional assessment or response to malnutrition.
Poor EN/TPN management: Formula issues, early discontinuation.
Inadequate Monitoring: Missed weight, intake, or biochemistry changes.
GI Surgeries: Impaired digestion and nutrient absorption.
Infections/Sepsis: Increased nutrient requirements.
Long Hospital Stays: Decreased appetite, immobility, muscle wasting.
Prevention:
Regular assessments and monitoring.
Early interventions for high-risk patients.
Address medication side effects.
Use of MDT approaches and SOPs for malnutrition management.
Malnutrition in Developing Countries
Kwashiorkor:
Cause: Protein deficiency.
Symptoms: Pot belly, oedema, loss of appetite, enlarged fatty liver, lethargy, mild muscle wasting.
Marasmus:
Cause: Severe energy deficiency (CHO, protein, fat).
Symptoms: Prominent bones, severe muscle and fat loss, no oedema.
Key Notes for Practice (Malnutrition)
Chronic inflammation is a hallmark of malnutrition in chronic and acute diseases.
Regular monitoring of pre-albumin and creatinine can help detect acute muscle wasting.
Vigilant assessment and early intervention are critical for preventing iatrogenic malnutrition.
Kwashiorkor and Marasmus differ in etiology and clinical presentation (oedema in Kwashiorkor, muscle wasting in Marasmus).
Refeeding Syndrome Definition
What: A metabolic complication triggered by reintroducing normal caloric intake in a malnourished state.
Cause: Shift in electrolytes and metabolic changes, particularly due to carbohydrate (CHO) reintroduction.
Pathophysiology of RFS
Starvation Phase:
Energy from protein and fat, low insulin production, depletion of thiamin, phosphate (PO4), magnesium (Mg), potassium (K+), and corrected calcium (Corr. Ca).
Refeeding Phase:
Sudden CHO intake → insulin spike → glucose, electrolytes, and thiamin shift intracellularly → rapid depletion of extracellular nutrients.
RFS Signs & Symptoms
Electrolyte Imbalances:
Hypokalaemia, hypophosphataemia, hypomagnesaemia, hypocalcaemia.
Cardiac & Respiratory: Irregular heart rhythms, breathing difficulties.
Neuromuscular: Muscle cramps, general weakness, seizures, or coma in severe cases.
Other: Glucose intolerance, fluid retention (Na and H2O).
Refeeding Blood Reference Values
Potassium (K+):
Normal: 3.5 - 5.1 mmol/L.
Critical: <3 mmol/L.
Magnesium (Mg):
Normal: 0.77 - 1.33 mmol/L.
Critical: <0.6 mmol/L.
Phosphate (PO4):
Normal: 0.8 - 1.45 mmol/L.
Critical: <0.4 mmol/L.
Risk Factors for RFS
High Risk (1 or more):
BMI <16.
Unintentional weight loss >15% in 3-6 months.
No nutrient intake >10 days.
Low pre-feeding K+, PO4, Mg.
Anorexia nervosa.
At Risk (2 or more):
BMI <18.5.
Unintentional weight loss >10% in 3-6 months.
No nutrient intake >5 days.
Alcohol or drug abuse (including insulin, chemo, antacids, diuretics).
RFS Treatment Approach
- Caloric Intake:
Start at 25kcal/kg/day for the first 2 days.
Gradually increase as tolerated, not exceeding 1000kcal/day initially. - Electrolyte Monitoring & Supplementation:
Daily monitoring; IV supplementation as needed.
Potassium (K+): 2 - 4 mmol/kg/day.
Phosphate (PO4): 0.3 - 0.6 mmol/kg/day.
Magnesium (Mg): 0.2 mmol/kg IV or 0.4 mmol/kg/day PO. - Thiamine Supplementation:
200-300mg/day to prevent deficiency. - Vitamin Support:
Multivitamins and vitamin B complex.
RFS Key Takeaways
RFS is life-threatening and requires close monitoring.
Hallmarks: Hypokalaemia, hypophosphataemia, and hypomagnesaemia.
Gradual caloric reintroduction and proactive electrolyte and vitamin supplementation are essential to prevent complications.
Nutrition Support - Enteral Nutrition
Indication: For patients unable to meet nutritional needs orally.
When to Start:
Deficit 30-40%: Consider supplemental EN with dietary modifications/ONS.
Deficit >40%: EN required if oral/ONS insufficient
Types of EN Tubes
NG (Nasogastric): Short-term (<4 weeks), higher aspiration risk.
NJ/Nasoduodenal: Post-pyloric insertion; for aspiration risk or gastric issues.
Gastrostomy: Long-term feeding.
PEG: Endoscopic insertion, rotate to prevent buried bumper syndrome.
RIG: Radiologic insertion, for obstructions or inability to access orally.
JEJ (Jejunostomy): For high aspiration risk, GI absorption issues, or UGI surgery.
Routes of Feeding
NGT: Short-term (<14 days), no gastroparesis, vomiting, or reflux history.
PEG: Long-term (>3 weeks), fully functional gut (not for GORD or gastroparesis).
PEJ/NJ: Long-term (>3 weeks), impaired gastric function or history of aspiration.
Complications of EN
Common Issues:
Aspiration pneumonia.
GI intolerance (bloating, diarrhea).
Buried bumper syndrome (PEG).
Solutions:
Post-pyloric tube if aspiration risk persists.
Adjust feed rates or formula composition.
Methods of EN Administration
Pump Feeding: Precise, continuous rate; reduces GI distress.
Gravity Feeding: Controlled rate but time-intensive.
Bolus Feeding: Large volumes mimicking meals; less restrictive but higher aspiration risk.
Continuous Infusion: Over 16-24 hours; better glycemic control.
Intermittent Feeding: Periodic feedings with 4+ hour breaks.
Signs of Poor Tolerance in EN Feeding
Vomiting: Suggests volume or feed composition issues.
Abdominal Distension: Indicates gas accumulation or motility issues.
Diarrhea: Suggests nutrient absorption issues or feed intolerance.
Large Gastric Aspirates: >250-500ml indicates delayed gastric emptying.
Types of Enteral Feeds
Standard Formulas: Balanced nutrition (1-1.2 kcal/ml).
Macronutrient breakdown: 15% Protein, 30% Fat, 55% CHO.
Fibre content:
Fibre-Containing: For long-term feeders; supports regularity.
Fibre-Free: For critically ill or severe gut dysmotility.
Specialised Formulas:
Arginine-Enriched: Wound healing, tissue repair.
Diabetes Formulas: Slow-digesting CHO for glycemic control.
Respiratory Formulas: Low CHO to reduce CO2 production.
Renal Formulas: Low protein, phosphorus, sodium, potassium.
Water Flushes (EN)
Purpose: Prevent blockages, maintain tube patency, and meet hydration needs.
Frequency: Every 4-6 hours or as per clinical guidelines.
Additional Needs: Adjust for fever, heat, or limited PO fluids.
Parenteral Nutrition
Indication: For non-functional GI tract or inability to meet needs via EN/oral.
Examples: Radiation enteritis, ileus, severe pancreatitis, severe IBD.
Administration:
Central Line: For long-term or high kcal needs; catheter in superior vena cava.
Peripheral (PICC): For short-term use, lower kcal requirements.
Complications & Monitoring in PN
Central Line Issues: Infection, thrombosis, catheter misplacement.
Monitoring:
Regular bloodwork to assess electrolytes and nutrient levels.
Adjust formulas based on clinical response and tolerance.
EN support planning:
Impaired absorption or digestion -> elemental or semi-elemental formula
Electrolyte restriction -> renal formula
Fluid restriction or high energy needs -> high energy formula (1.5 - 2.0 kcal/ml)
High protein needs -> high protein standard formula (1 - 1.2 kcal/ml)
Considerations when choosing a formula feed
Osmolality:
- 300 - 500 mOsm/kg = formula has approximately the same concentration of solutes in blood
- Optimises absorption of formula, usually used when feeding into small intestine (intestinal failure, short bowel syndrome) or poor tolerance of standard/polymeric feeds
Speciality formulations:
- Designed for diabetes, respiratory disorders or wound healing
- Low sodium, branched-chain amino acids, high fat low CHO
