From the Guidelines
The correct answer is B. 150 g protein/day. For a patient receiving 1,800 calories per day through total parenteral nutrition (TPN), the recommended protein requirement would be approximately 150 grams per day. This calculation is based on the standard protein requirement for critically ill patients receiving TPN, which typically ranges from 1.2 to 2.0 g/kg/day of protein, as recommended by the American Society for Parenteral and Enteral Nutrition (ASPEN) and the European Society for Clinical Nutrition and Metabolism (ESPEN) 1. For an average adult weighing about 70-80 kg, this would translate to approximately 150 grams of protein daily, considering the minimum protein target of 1.2 g/kg/day as suggested by ASPEN and ESPEN guidelines 1. Protein is essential during TPN therapy to prevent muscle wasting, support wound healing, maintain immune function, and provide necessary amino acids for tissue repair. This amount of protein (150 g) represents about 33% of the total caloric intake, which falls within the appropriate range for balanced parenteral nutrition, as protein should be supplied at 1.0 –1.5 g/kg per day, based on ideal body weight for adults 1. The other options either provide insufficient protein (125 g) or excessive amounts (200 g, 250 g, 300 g) that could potentially cause metabolic complications such as azotemia or hepatic dysfunction in a patient receiving only 1,800 calories per day. Key considerations in determining protein requirements include the patient's ideal body weight, age, and clinical condition, as well as the need to balance protein intake with energy provision to optimize outcomes 1. In clinical practice, it is crucial to monitor patients' nutritional status, adjust protein intake accordingly, and prioritize individualized nutrition support to minimize morbidity, mortality, and improve quality of life. Some patients may require higher or lower protein intake based on specific conditions, such as renal or hepatic impairment, and careful consideration of these factors is necessary to provide optimal nutrition support 1.
From the Research
Protein Requirements for Total Parenteral Nutrition
To determine the protein requirements for a patient receiving 1,800 cal/day in total parenteral nutrition, we need to consider the following factors:
- The patient's daily caloric intake
- The type and amount of calories infused
- The patient's nutritional state
Relevant Studies
Based on the provided studies, we can see that:
- A study published in 1980 2 found that increasing the amino acid concentration from 2.5 to 5% had no effect on the rate at which the body cell mass increased.
- The same study found that carbohydrate calories were more efficient than lipid calories in restoring a depleted body cell mass.
- Another study published in 1985 3 found that total parenteral nutrition can effectively quench protein catabolism and enhance protein synthesis.
Protein Requirements
However, none of the provided studies directly address the protein requirements for a patient receiving 1,800 cal/day in total parenteral nutrition. Some key points to consider are:
- The general protein requirements for adults are typically in the range of 0.8-1.2 grams of protein per kilogram of body weight per day.
- Patients receiving total parenteral nutrition may have higher protein requirements due to their increased metabolic needs.
- The optimal protein intake for patients receiving total parenteral nutrition is not well established and may vary depending on individual factors such as the patient's nutritional state and the type and amount of calories infused.
Possible Answer Choices
Based on the general protein requirements for adults, we can estimate the protein requirements for a patient receiving 1,800 cal/day in total parenteral nutrition as follows:
- Assuming a typical adult weight of 70 kg, the protein requirements would be approximately 56-84 grams of protein per day (0.8-1.2 grams of protein per kilogram of body weight per day).
- However, this is just an estimate, and the actual protein requirements for a patient receiving total parenteral nutrition may be higher or lower, depending on individual factors.
- The answer choices provided are:
- A. 125 g protein/day
- B. 150 g protein/day
- C. 200 g protein/day
- D. 250 g protein/day
- E. 300 g protein/day
- Without more specific information about the patient's nutritional state and the type and amount of calories infused, it is difficult to determine which answer choice is correct.