A 72-year-old woman with a long history of severe Crohn’s disease presents with significant weight loss (BMI 14 kg/m²) and has been NPO for 5 days due to an ileus. She reports frequent exacerbations and admits to missing doses of her immunomodulator and not following her complex dietary plan because she finds the instructions overwhelming. Which of the following social determinants of health is the most significant risk factor contributing to her malnutrition?

A 62-year-old man is in the ICU on assist-control ventilation for ARDS. He is receiving a norepinephrine infusion via central line to maintain MAP. Due to severe pancreatitis with prolonged ileus, he has been without nutrition for 12 days. Baseline labs: phosphate 2.5 mg/dL (2.5–4.5), potassium 3.0 mEq/L (3.5–5.0), magnesium 1.4 mg/dL (1.7–2.2). You plan to start parenteral nutrition. Which pathophysiological mechanism BEST explains the potential for worsening hypophosphatemia, hypokalemia, and hypomagnesemia during the initial phase of refeeding?

A 62-year-old man is admitted to the critical care unit following a severe motor vehicle accident and is currently intubated on assist-control ventilation. He has multiple traumatic injuries, including a splenic laceration requiring embolization and a femur fracture. A central venous catheter is in place, and he is receiving a continuous norepinephrine infusion for hemodynamic support. His body mass index (BMI) is 28 kg/m² (approximately 80 kg), and he has no history of chronic malnutrition. Enteral nutrition was initiated via nasogastric tube 24 hours ago but is currently tolerated at only 20 mL/hour of a 1 kcal/mL formula, providing less than 500 kcal/day—under 25% of his estimated requirement of 25 kcal/kg/day (≈2000 kcal/day). Given this patient’s clinical status, which of the following is the most appropriate management strategy for his nutrition support at this time?

A 45-year-old female is on ICU day 5 for severe sepsis requiring mechanical ventilation. She remains on low-dose norepinephrine (0.05 µg/kg/min) via a central line but is hemodynamically stable (MAP 70 mm Hg). Her history includes Crohn’s disease with multiple resections leading to short bowel syndrome and a baseline BMI of 16 kg/m². She has been NPO since admission due to severe ileus and high-output jejunostomy, and two attempts at enteral feeding failed. Labs show albumin 2.1 g/dL (normal 3.5–5.0 g/dL) and prealbumin 8 mg/dL (normal 15–35 mg/dL). Nutrition support is being considered. Considering her pre-existing malnutrition, ongoing critical illness, and contraindications to enteral nutrition, which of the following is the MOST appropriate initial nutrition support strategy?

A 62-year-old man is admitted to the ICU after a severe aspiration event and is intubated on assist-control ventilation. He is receiving a continuous norepinephrine infusion for septic shock. His baseline BMI is 24 kg/m² with no history of malnutrition. Attempts at enteral nutrition via nasogastric tube over 48 hours have failed due to high gastric residual volumes (>500 mL) and abdominal distension despite prokinetic therapy. His blood glucose is 165 mg/dL and liver function tests are normal. Considering his nutritional history and current clinical status, which of the following is the MOST appropriate initial approach to parenteral nutrition (PN) initiation?

A 65-year-old man is admitted to the critical care unit for severe acute pancreatitis. He is on mechanical ventilation and receiving a continuous norepinephrine infusion via a central venous catheter. He has well-controlled hypertension and no history of malnutrition. He has been NPO for 3 days due to severe ileus, and multiple attempts at enteral nutrition via nasogastric tube have failed because of gastric residual volumes consistently >500 mL over 4 hours. His albumin is 3.8 g/dL and prealbumin is 18 mg/dL. Which of the following is the most appropriate initial strategy for this patient’s parenteral nutrition?

A 58-year-old male in the ICU with severe pancreatitis has been fasting for 10 days and was started on parenteral nutrition (PN) 24 hours ago. He now presents with lethargy, generalized muscle weakness, and premature ventricular contractions on telemetry. Laboratory values are: serum phosphate 1.2 mg/dL (normal 2.5–4.5 mg/dL), potassium 3.0 mEq/L (3.5–5.0 mEq/L), magnesium 1.2 mg/dL (1.7–2.2 mg/dL), and glucose 180 mg/dL. Which metabolic complication of initiating PN is MOST likely responsible for his presentation?

A 68-year-old man is in the intensive care unit for septic shock. He is intubated on assist-control ventilation and receiving a continuous norepinephrine infusion via a central line. He has been NPO for 4 days due to severe ileus and has developed acute kidney injury requiring continuous renal replacement therapy (CRRT). His pre-admission BMI was 19 kg/m², and he reports an unintentional weight loss of 10% over the past 3 months. Current labs include Na 138 mEq/L, K 3.2 mEq/L, Mg 1.4 mg/dL, PO₄ 1.8 mg/dL, and glucose 145 mg/dL. Parenteral nutrition (PN) is being considered. Which of the following is the most appropriate initial approach to parenteral nutrition for this patient?

A 62-year-old man (weight 75 kg, BMI 24 kg/m2) is admitted to the MICU with severe septic shock from community-acquired pneumonia. He is mechanically ventilated and receiving escalating norepinephrine (0.3 mcg/kg/min) via a central line. He has no history of malnutrition. Enteral nutrition (EN) was started 48 hours ago at 25 mL/hour via a gastric tube (goal 25 kcal/kg/day ≈ 1875 kcal/day), but over the past 72 hours he has had gastric residual volumes > 500 mL despite metoclopramide and erythromycin. A trial of post-pyloric feeding also failed due to intolerance. He remains hemodynamically unstable. What is the most appropriate next step in nutrition support?

A 62-year-old man is admitted to the ICU with severe sepsis and multi-organ dysfunction. He is on assist-control mechanical ventilation and receiving norepinephrine via a central line. His BMI is 28 kg/m² with no history of chronic malnutrition. Enteral nutrition (EN) was started on Day 1 via nasogastric tube at a trophic rate, but due to persistent gastric ileus, he is tolerating only 20% of his caloric goal at 72 hours. Which of the following is the most appropriate action regarding nutrition support?