Nutrition

A 70 kg 66-year-old woman with end-stage renal disease (ESRD) on hemodialysis (HD) requires total parenteral nutrition (TPN) during her hospitalization. Which TPN composition parameter would be considered appropriate for this patient?

• 15% dextrose solution

• 30% IV fat emulsion

• 210 g protein (3 g/kg/day)

• 105 G protein (1.5 g/kg/day)

• 3,500 mL water (50 mL/kg/day)

Answer explanation

• Patients with acute kidney injury (AKI) or chronic kidney disease (CKD) may have underlying inflammation and altered fluid status.

• • Energy requirements may be increased in these patients.

  • Protein intake recommendations are varied based on renal disease and therapy:

    • -Continuous renal replacement therapy: 1.8 to 2.5 g/kg/d

    • -AKI with hemodialysis: 1.5 to 2.5 g/kg/d

    • -Stage V CKD with hemodialysis: 1.2 g/kg/d

    • -Stage V CKD with peritoneal dialysis: 1.3 g/kg/d

    • -In patients with stage III or IV CKD, it remains unclear if decreased protein intake prevents the progression of kidney disease.

Ammonia is byproduct of protein metabolism and a highly potent neurotoxin. Decreased ammonia clearance leads to encephalopathy

A 25-year-old man is admitted following a major trauma that was complicated by sepsis.

Which of the following is the CORRECT daily calorie and protein requirements?

• 25 kcal/kg/day and 1.0 g protein/kg/day

• 25 kcal/kg/day and 1.5 g protein/kg/day

• 35 kcal/kg/day and 1.5 g protein/kg/day

• 35 kcal/kg/day and 2.5 g protein/kg/day

• 40 kcal/kg/day and 2.5 g protein/kg/day

Answer explanation

Estimated energy requirements must consider organ function, body weight, and the clinical condition

Baseline energy requirement for a surgical patient is 25 kcal/kg/day with 1-1.5 g of protein/kg/day,

Burn patients need 35-40 kcal/kg/day and 2-2.5 g of protein/kg/day

Trauma patients with sepsis require about 30-35 kcal/kg/day and 1.5-2 of protein/kg/day

Trauma patients without sepsis require about 25-30 kcal/kg/day and 1.5 of protein/kg/day

Regardless of the stress status, It is rare that a patient energy expenditure exceeds 3,000 kcal per day

Burn patients require a large increase in energy.  This is why it is imperative to place a nasogastric tube and start tube feeding immediately after the initial resuscitation.

A 35-year-old man is hospital day 7 in the ICU due to a severe attack of acute necrotizing pancreatitis. His current weight is 100 kg. Several attempts to start him on enteral feeding have failed due to persistent ileus, so he was started on total parenteral nutrition (TPN). Assuming his current daily caloric requirement is 25 kcal/kg per day and his protein requirement is 1.5 g/kg per day. How many non-protein calories should the patient get per day through his TPN?

• 2,200 kcal/day

• 1,500 kcal/day

• 1,900 kcal/day

• 1,650 kcal/day

• 2,500 kcal/day

Answer explanation

Daily caloric requirement: 100 kg x 25 kcal/kg = 2,500 kcal/day

Daily protein requirement: 100 kg x 1.5 g/kg = 150 g/day

Caloric values of TPN:

• -Protein: 4 kcal/g

• -Dextrose: 3.4 kcal/g

• -Lipids: 9 kcal/g

Total protein calories: 150 g x 4 kcal/g = 600 kcal/day

Dextrose and lipids (nonprotein calories): 2,500 - 600 = 1,900 kcal per day

When administering parenteral nutrition, central administration is preferred. When placing central venous catheter in the IJ, what is the best reason for using ultrasound?

• To reduce CLABSI regardless of site

• To reduce pneumothoraces

• To reduce all complications from IJ catheters

• To properly situate catheter tips after all lines

• To reduce number of placement attempts

Answer explanation

Level 1 evidence shows that ultrasound decreases incidence of all complications of central venous access in IJ and femoral vein

Which of the following is the definition of respiratory quotient?

• CO2 produced/O2 consumed

• O2 consumed/CO2 produced

• CO2 consumed/O2 produced

• CO2 produced/O2 produced

• O2 produced/CO2 consumed

Answer explanation

• -RQ can help identify overfeeding or underfeeding

  • -An RQ greater than 1 results from lipogenesis (overfeeding from excess carbohydrates).

    • -Overfeeding can result in hyperglycemia and hypertriglyceridemia.

    • -Overfeeding can also make it more challenging to wean a patient from mechanical ventilation, given the extra CO₂ that is generated and must be expired.

  • -An RQ less than 0.7 results from ketosis and fat oxidation (starvation).

Which one of the following statements about nitrogen balance is correct?

• Nitrogen balance is the ratio of intake of nitrogenous compounds / output of nitrogenous metabolites from. the body

• In nitrogen equilibrium the excretion of nitrogenous metabolites is greater than the dietary intake of nitrogenous compounds.

• Positive nitrogen balance means that there is a net loss of protein from the body

• In positive nitrogen balance the excretion of nitrogenous metabolites is less than the dietary intake of nitrogenous compounds.

• In negative nitrogen balance the excretion of nitrogenous metabolites is less than the dietary intake of nitrogenous compounds

A 72-year-old male smoker is found to have an oropharyngeal squamous cell carcinoma. He has lost 18 kg (40 lb) over the last month and has not been able to tolerate oral intake. He is referred for a Stamm gastrostomy. What is the recommended position of the gastrostomy through the skin?

• 1 cm below costal margin and 1 cm left of midline

• 1 cm below costal margin and 1 cm to the right of midline

• 3 cm below costal margin and 1 cm to the left of midline

• 3 cm below costal margined 3 cm to the left of midline

• 3 cm below the costal margin and 3 cm to the right of midline

Answer explanation

A gastrostomy tube can be used for many conditions, which can be grouped into two main categories: decompression and enteral nutrition. Stamm gastrostomy is by far the most common open operation for gastrostomy tube placement. Currently, the endoscopically placed gastrostomy tube (PEG) is still more prevalent. The Stamm may be chosen when the anatomy is hostile, multiple operations and adhesions are present, and PEG is not safe to accomplish.  

The recommended location for Stamm gastrostomy placement is 3 cm below the costal margin and 3 cm to the left of midline, in the anterior wall of the body of the stomach. Once the abdomen is opened, the anterior body of the stomach is grasped and a purse string is made. A gastrostomy is made within the purse string and the gastric tube is placed. A stab incision is made in the anterior abdominal wall and the tube is brought out through the abdomen. It is then sewn to the peritoneum and the skin for security.

What is the most common complication of PEG placement?

• Refeeding syndrome

• Gastrocolocutaneous fistula

• Infection at PEG tube site

• Hemorrhage

• Accidental extubation of PEG tube

Answer explanation

All are potential complications of percutaneous endoscopic gastrostomy (PEG) tube placement, superficial infection at the insertion site is the most common complication, occurring in 5.4% to 17.0%. Administration of preoperative antibiotics (typically a third-generation cephalosporin) has been shown to significantly reduce the rate of insertion site infection and should be part of any PEG tube placement. If the patient is already on antibiotics preoperatively, there is no need to add additional antibiotics.

The vast majority of these infections, around 70% in some studies, are minor and resolve with antibiotics alone and do not require further intervention.

In what conditions would you prefer jejunal feeding tube placement over gastric?

• Gastroparesis

• Delayed gastric emptying

• Gastric outlet obstruction

• All the above

What is the best marker of nutritional status in a stable patient in the outpatient setting?

• Albumin

• Prealbumin

• Transferrin

• C reactive protein