BCNSP cheat sheet

Ideal body weight (IBW): males 50 kg + 2.3 kg per inch >5 ft; females 45.5 kg + 2.3 kg per inch >5 ft.

BMI = weight (kg) / height (m)^2; underweight <18.5, normal 18.5–24.9, overweight 25–29.9, obese ≥30.

Caloric requirements: 25–30 kcal/kg/day for stable adults; 30–35 kcal/kg/day for critically ill or hypermetabolic; obesity uses adjusted body weight and hypocaloric feeding.

Protein: 0.8 g/kg/day healthy adults; 1.2–2.0 g/kg/day stressed, critically ill, or burn patients; 1.2–1.5 g/kg/day for CKD on dialysis (individualize).

Fluid: 30–35 mL/kg/day or 1 mL/kcal; adjust for fever, drains, renal, and cardiac status.

Nitrogen balance = (protein intake g / 6.25) − (urine urea nitrogen g + 4 g); positive balance indicates anabolism.

Albumin (half-life ~20 days) and prealbumin (half-life ~2 days) are negative acute-phase reactants; low values reflect inflammation, not reliably nutritional status.

Indirect calorimetry measures resting energy expenditure via VO2 and VCO2; RQ >1.0 suggests overfeeding, <0.7 suggests underfeeding.

Enteral nutrition is preferred when the GI tract is functional: "if the gut works, use it" - lower infection risk and cost than parenteral nutrition.

Enteral contraindications: mechanical bowel obstruction, severe ischemic bowel, uncontrolled GI bleed, high-output proximal fistula, severe malabsorption, hemodynamic instability with gut hypoperfusion.

Parenteral nutrition indications: short bowel syndrome, high-output fistula, severe pancreatitis with intolerance to enteral feed, prolonged ileus, bone marrow transplant mucositis, severe malnutrition when enteral is not feasible.

Gastric access (NG, PEG) is preferred for short-term (<4 weeks NG) and long-term (>4 weeks PEG) when the stomach and small bowel function.

Post-pyloric (NJ, PEJ) access is indicated for gastroparesis, severe GERD, pancreatitis, or high aspiration risk.

PEG placement requires a patent GI tract and absence of ascites, coagulopathy, or peritonitis; risk of peristomal infection and buried bumper syndrome.

Central venous access for PN: TPN requires a central line (PICC, tunneled catheter, port); peripheral PN is limited to <900 mOsm/L and short duration.

Refeeding risk is highest in patients with BMI <16, weight loss >15% in 3–6 months, negligible intake >10 days, or low electrolytes; start low and advance slowly.

Standard polymeric formulas: 1.0–1.2 kcal/mL, intact protein, require functioning digestion and absorption.

Elemental (monomeric) formulas contain free amino acids or peptides and are low-residue; use in malabsorption, short bowel, or pancreatic insufficiency.

Disease-specific formulas: pulmonary (higher fat, lower carbohydrate), renal (lower protein, electrolyte-restricted), hepatic (branched-chain amino acid enriched), immune-modulating (arginine, glutamine, omega-3).

Initiation: start at 10–30 mL/hr and advance by 10–20 mL/hr every 4–8 hours to target over 24–48 hours; gastric residual volume check is not routinely required unless high risk.

Head-of-bed elevation 30–45 degrees reduces aspiration; post-pyloric feeding further reduces aspiration risk.

Monitoring: daily weights, fluid balance, electrolytes, glucose, and GI tolerance (nausea, distention, diarrhea); check tube position before use.

Formula contamination risk: hang time ≤4 hours for open-system formulas; change feeding sets every 24 hours.

Refeeding syndrome monitoring: check phosphate, potassium, magnesium daily during first week of feeding in at-risk patients.

PN components: dextrose (usually 10–35% for central, ≤10% peripheral), amino acids (3–15%), lipid emulsion (10–20%), electrolytes, vitamins, trace elements, and insulin as needed.

Dextrose provides 3.4 kcal/g; amino acids 4 kcal/g; lipid 20% emulsion provides 2.0 kcal/mL (10 kcal/g).

Peripheral PN osmolarity should be ≤900 mOsm/L; central PN can exceed 900 mOsm/L.

Calcium and phosphate can precipitate; use compatible salts and check for precipitate; do not add calcium to phosphate-containing solutions without compatibility data.

Lipid emulsions: limit to ≤1 g/kg/day (or ≤2 g/kg/day in some settings); monitor triglycerides, especially in hypertriglyceridemia or pancreatitis.

Compounding requires aseptic technique in a laminar flow hood; verify order, label, and expiration; 2-in-1 vs 3-in-1 (total nutrient admixture) stability considerations.

Cycling PN over 12–16 hours may reduce hepatic steatosis and improve patient mobility; taper to avoid rebound hypoglycemia.

Monitoring: glucose, electrolytes, renal and hepatic function, triglycerides, and fluid balance; adjust daily initially then weekly.

Enteral complications: aspiration, diarrhea, constipation, tube clogging, dislodgement, GI intolerance, hyperglycemia, refeeding syndrome.

Parenteral complications: catheter-related bloodstream infection, thrombosis, pneumothorax, hyperglycemia, electrolyte imbalance, hepatic steatosis, gallbladder sludge, metabolic bone disease.

Refeeding syndrome: hallmark is hypophosphatemia, hypokalemia, hypomagnesemia; start feeding at 10–20 kcal/kg/day and replete electrolytes.

Hyperglycemia management: target glucose 140–180 mg/dL; insulin infusion or sliding scale; avoid overfeeding dextrose.

Diarrhea in enteral feeding: evaluate formula osmolality, infusion rate, medications (sorbitol, antibiotics), and infection (C. difficile).

Catheter sepsis prevention: strict aseptic technique, chlorhexidine skin prep, minimize line accesses, and remove unnecessary lines.

Hepatic complications of PN: elevated transaminases, steatosis, cholestasis; strategies include cycling PN, limiting dextrose, and using fish-oil-based lipids.

Monitoring frequency: daily weights and electrolytes during acute phase; weekly labs once stable; reassess nutritional goals regularly.

Diabetes: use consistent carbohydrate intake, monitor glucose, and adjust insulin; enteral formulas with lower glycemic index may help.

Renal failure: restrict protein (0.6–0.8 g/kg/day pre-dialysis), potassium, phosphorus, and fluid; dialysis patients need higher protein (1.2–1.5 g/kg/day).

Liver disease: provide adequate protein (1.2–1.5 g/kg/day) and calories; do not restrict protein in encephalopathy; consider branched-chain amino acids.

Pancreatitis: enteral nutrition (nasojejunal) is preferred over parenteral; start low-fat formula; parenteral if enteral not tolerated.

Short bowel syndrome: high-calorie, low-fat, low-oxalate diet; supplemental vitamins and minerals; parenteral nutrition may be needed long-term.

Critical illness: early enteral nutrition within 24–48 hours; trophic feeding if not tolerating full feeds; avoid overfeeding.

Transitions of care: develop a discharge plan including home enteral or parenteral nutrition training, follow-up appointments, and monitoring parameters.

Home PN: requires trained caregiver, sterile technique, and regular monitoring; complications include catheter infections and liver disease.