Parenteral Nutrition Flashcards
A pregnant patient is admitted with hyperemesis gravidarium (HEG). Which of the following is a clinical indication for PN use?
1: Vomiting NOT controlled with supportive care within 48 hours
2: Intolerance to EN trial and supportive care measures
3: Patient refusal of EN tube placement
4: Fluid and electrolyte imbalances
2: Intolerance to EN trial and supportive care measures
Hyperemesis gravidarum (HEG) is a severe form of pregnancy-induced nausea and vomiting. Due to the likelihood that the patient’s nutritional intake has been poor for several weeks due to vomiting, EN or PN may be required. Prior to implementation of nutritional therapy for HEG, fluid and electrolyte imbalances, ketonuria, and dehydration would be treated via IV fluid. Multivitamins with additional B vitamins are typically added to address suboptimal vitamin intake and prevent complications such as neuropathies (B6 and B12), Wernicke’s encephalopathy (thiamine), and neural tube defects (folic acid). Antiemetic treatment would begin and oral intake would temporarily be avoided. Initiation of an EN trial for HEG would be appropriate if the patient is still unable to take oral feedings after 24-48 hours of supportive therapy as listed above. If the EN trial fails due to exacerbated nausea, vomiting, diarrhea, significant gastric residuals, or tube displacement and is associated with clinically significant weight loss (greater than 5% of body weight), it is appropriate to begin PN
Rapid intravenous infusion of potassium phosphate may result in
1: thrombophlebitis.
2: hypercalcemia.
3: metabolic alkalosis.
4: vitamin D deficiency.
1: thrombophlebitis.
Infusion rates of phosphate should not exceed 7 mmol/h because faster infusion rates can often cause thrombophlebitis (ie, potassium phosphate) and metastatic calcium-phosphate deposition with potential resultant organ dysfunction.
What is the most common complication associated with PN administration?
1: Hypophosphatemia
2: Renal dysfunction
3: Sepsis
4: Hyperglycemia
4: Hyperglycemia
Hyperglycemia is the most common complication associated with PN administration and can be caused by various factors. Stress-associated hyperglycemia in acutely ill and septic patients often develops as a result of insulin resistance, increased gluconeogenesis and glycogenolysis, and suppressed insulin secretion.
Stress-associated hyperglycemia in acutely ill and septic patients often develops as a result:
(name 4)
- insulin resistance,
- Increased gluconeogenesis (non CHO –> glucose)
- Increased glycogenolysis (glycogen –> glucose)
- suppressed insulin secretion
What is the glycemic target for the majority of critically ill adult patients?
1: 80 to 110 mg/dL
2: 220 to 240 mg/dL
3: 140 to 180 mg/dL
4: 180 to 220 mg/dL
3: 140 to 180 mg/dL
The current recommendation for glycemic target by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) is to maintain the glucose level between 140-180 mg/dL for the majority of critically ill adult patients. Lower glucose targets (110 mg/dl to 140 mg/dL) may be appropriate for some patients, but this is only appropriate when this can be safely achieved. Targets less than 110 mg/dl are not recommended due to the adverse effects of hypoglycemia.
What is the preferred approach recommended by the American Association of Clinical Endocrinologists (AACE) and the American Diabetes Association (ADA) for subcutaneous insulin administration in the hospitalized adult patient with diabetes mellitus?
1: Sliding-scale insulin therapy
2: Basal insulin therapy
3: Bolus insulin therapy
4: Basal-bolus insulin therapy
4: Basal-bolus insulin therapy
The preferred approach for subcutaneous insulin administration is basal-bolus insulin therapy. This approach allows for basal insulin administered for hepatic glucose output combined with scheduled bolus insulin administered for meal times. There are three components to basal-bolus insulin therapy; basal insulin, nutritional component prior to meals and a correctional insulin.
Which form of glutamine supplementation improves physical compatibility and stability for admixture in PN solutions?
1: Glutamine dipeptide
2: Free glutamine
3: L-glutamine powder
4: Protein bound glutamine.
1: Glutamine dipeptide
Glutamine supplementation is available in parenteral solutions, some predigested enteral formulas, and oral nutrition supplements. Glutamine dipeptide products such as L-alanyl-L-glutamine and Glycyl-L-glutamine improve water solubility, stability during heat sterilization, and the capability for prolonged shelf life when compounding in parenteral solutions. Free glutamine is unstable in parenteral solutions. Parenteral glutamine supplementation is more beneficial than enteral supplementation. Enteral glutamine is protein bound and it is difficult to determine the exact glutamine content. L glutamine powder is used in oral nutrition supplements.
Which of the following additives has the greatest risk of destabilizing the intravenous fat emulsion (IVFE) in a total nutrient admixture (TNA)?
1: Sodium chloride
2: Calcium acetate
3: Iron dextran
4: Potassium phosphate
3: Iron dextran
Phase separation and the liberation of free oil from the destabilization of TNAs can result over time when an excess of cations is added to a given formulation. The higher the cation valence, the greater the destabilizing power; thus, trivalent cations such as Fe +3 (from iron dextran) are more disruptive than divalent cations such as calcium and magnesium. Monovalent cations such as sodium and potassium are least disruptive to the emulsifier, yet when given in sufficiently high concentrations, they may also produce instability. There is no safe concentration of iron dextran in any TNA.
Which of the following factors has been associated with an increase in prescribing errors related to PN formulations?
1: Standardized PN order form
2: Calculation of PN dosages
3: PN components ordered as amount per day
4: PN components listed in same sequence on order form as PN label
2: Calculation of PN dosages
Common factors associated with the majority of PN prescribing errors include: inadequate knowledge regarding PN therapy, certain patient characteristics related to PN therapy (e.g., age, impaired renal function), miscalculation of PN dosages, specialized PN dosage formulation characteristics, and prescribing nomenclature.
According to the A.S.P.E.N. PN Safety Consensus Recommendations, which of the following is the best method to express the dextrose content on the label of a PN formulation in order to avoid misinterpretation?
1: Volume of the percent original concentration added (e.g., 500 mL of 50% dextrose)
2: Grams per liter (e.g., 250g/L)
3: Percent of final concentration after admixture (e.g., 35% dextrose)
4: Grams per 24-hour nutrient infusion (e.g., 225 g/day)
4: Grams per 24-hour nutrient infusion (e.g., 225 g/day
PN ingredients shall be ordered in amounts per day for adults and amounts per kilogram per day for pediatric and neonatal patients. This limits the confusion of conversion from amounts per liter, percent concentration, or volume. Amount per day refers to macronutrients in grams per day and micronutrients in mEq, mmol, mcg, or mg per day.
According to the A.S.P.E.N. PN Safety Consensus Recommendations all of the following are considered to be mandatory for the PN order form EXCEPT
1: Full generic name for each ingredient (unless brand name can identify unique properties of specific dosage form)
2: Recommended laboratory monitoring
3: Infusion schedule (continuous or cyclic)
4: Electrolytes ordered as complete salt form rather than individual ion
2: Recommended laboratory monitoring
The addition of recommended laboratory monitoring to PN order forms is strongly recommended, but it is not required.
A complete PN order shall contain the following: complete patient identifiers, birth date or age, allergies, height and dosing weight in metric units, diagnosis/diagnoses, indication(s) for PN, administration route/vascular access device (peripheral versus central), contact information for prescriber, date and time order submitted, administration date and time, volume and infusion rate, infusion schedule (continuous or cyclic), and type of formulation (TNA versus dextrose/amino acids with separate IVFE). PN ingredients shall be ordered as follows: amounts per day (for adult patients) or amounts per kilogram per day (for pediatric and neonatal patients), electrolytes as complete salt form, full generic name for each ingredient, using The Joint Commission approved abbreviations and avoiding ISMP error prone abbreviations, symbols, and dose designations, dose for each macronutrient and electrolyte, dose for vitamins (including MVI and individual entities), dose for trace elements (including multi-components and/or individual entities), dose for each non-nutrient medication.
According to the A.S.P.E.N. PN Safety Consensus Recommendations all of the following are considered to be mandatory for the inpatient PN label EXCEPT
1: infusion rate expressed in mL/h.
2: beyond-use date and time.
3: size of in-line filter (1.2 or 0.22 micron).
4: electrolyte content expressed in individual ions.
4: electrolyte content expressed in individual ions.
Ingredients are to be expressed on the PN label in the same sequence and units of measure as the PN order. Electrolytes are to be ordered as complete salt forms as opposed to individual ions.
The PN label should include the following: two patient identifiers, patient location or address, dosing weight in metric units, administration date and time, beyond use date and time, route of administration (central versus peripheral), prescribed volume and overfill volume, infusion rate in mL/h, duration of infusion (continuous versus cyclic), size of in-line filter (1.2 or 0.22 micron), completer name of all ingredients, barcode, all ingredients shall be listed in the same sequence and same units of measure as PN order, name of institution or pharmacy, and institution or pharmacy contact information (including telephone number). If IVFE is to be infused separately, the IVFE label should include: two patient identifiers, patient location or address, dosing weight, administration date and time, route of administration (central versus peripheral), prescribed about of IVFE and volume required to deliver that amount, infusion rate in mL/h, duration of infusion (not longer than 12 hours), complete name of IVFE, beyond use date and time, name of institution or pharmacy, and institution or pharmacy telephone number.
What is the nutritional value of the following PN order? 2400 mL with 300 grams dextrose and 90 grams protein in addition to 225 mL 20% IVFE.
1: 1830 kcal, 90 grams protein, 40 grams fat, 2625 mL
2: 2010 kcal, 90 grams protein, 40 grams fat, 2400 mL
3: 1830 kcal, 90 grams protein, 45 grams fat, 2625 mL
4: 1470 kcal, 90 grams protein, 45 grams fat, 2400 mL
3: 1830 kcal, 90 grams protein, 45 grams fat, 2625 mL
One (1) gram of dextrose is equal to 3.4 calories. One (1) gram of protein is equal to 4 calories. One (1) mL of 20% IVFE is equal to 2 calories. IVFE 20% provides 20 grams/100 mL; thus 225 mL provides 45 grams fat. 2400 mL plus 225 mL equals 2625 mL.
A patient who weighs 75 kg is receiving 65 mL/hour of a 2-in-1 PN solution that contains 117 grams protein and 273 grams dextrose in addition to 250 mL of 20% IVFE. What is the daily caloric content of this regimen per kg body weight?
1: 27.5 kcal/kg/day
2: 21.9 kcal/kg/day
3: 26.5 kcal/kg/day
4: 25.3 kcal/kg/day
4: 25.3 kcal/kg/day
One (1) gram of dextrose is equal to 3.4 calories. One (1) gram of protein is equal to 4 calories. One (1) mL of 20% IVFE is equal to 2 calories. The total daily caloric intake equals 468 kcal (protein) + 928 kcal (dextrose) + 500 kcal (IVFE) or 1896 kcal/day. When divided by the patient’s weight of 75 kg the total daily caloric intake per kg is 25.3 kcal/kg/day.
In the critically ill obese patient, specific guidelines for the provision of calories and protein have been recommended by both the Society of Critical Care Medicine and the American Society for Parenteral and Enteral Nutrition. For a patient with a BMI > 30 kg/m2, which of the following choices best reflects those recommendations for parenteral and enteral nutrition?
1: 15-20 kcal/kg ideal body weight/day & less than 2.0 g/kg ideal body weight/day
2: 15-20 kcal/kg ideal body weight/day & greater than or equal to 2.0 g/kg ideal body weight/day
3: 22–25 kcal/kg ideal body weight/day & less than 2.0 g/kg ideal body weight/day
4: 22–25 kcal/kg ideal body weight/day & greater than or equal to 2.0 g/kg ideal body weight/day
4: 22–25 kcal/kg ideal body weight/day & greater than or equal to 2.0 g/kg ideal body weight/day
Hypocaloric feeding with parenteral and enteral nutrition is generally recommended in the critically ill obese patient. For all classes of obesity where BMI is >30 kg/m2, the goal of the parenteral and enteral regimen should not exceed 65% to 70% of target energy requirements or 11–14 kcal/kg actual body weight/day Protein should be provided in a range greater than or equal to 2.0 g/kg ideal body weight/day for class I and class II patients (BMI 30–40 kg/m2), greater than or equal to 2.5 g/kg ideal body weight/day for class III (BMI > 40kg/m2).
Which of the following is a indication for the use of parenteral nutrition (PN)?
1: High output fistula
2: Crohn’s disease
3: Pancreatitis
4: Hyperemesis gravidarum
1: High output fistula
PN is indicated for a non-functioning or inaccessible gastrointestinal tract. PN is indicated in patients with a high output fistula (>500 mL/day). PN is not routinely needed as nutrition support for Crohn’s disease. The preferred route of administration for nutrition intervention in patients with acute pancreatitis is EN. Only patients with severe hyperemesis gravidarum refractory to EN and pharmacotherapy would require PN.
When is parenteral nutrition (PN) indicated in severe burn patients?
1: Total body surface area burn exceeds 20%
2: As soon as possible after admission due to extremely high caloric needs
3: Enteral nutrition is contraindicated or unlikely to meet nutrition needs
4: Within 7-10 days after hospital admission
3: Enteral nutrition is contraindicated or unlikely to meet nutrition needs
Several studies have found that the use of PN in patients with burns has been associated with increased mortality. The use of PN in patients with burns is, therefore, reserved for patients who are unable to be fed enterally.
The routine use of perioperative parenteral nutrition (PN) is indicated for patients with a non-functioning GI tract who are
1: normally nourished.
2: mildly to moderately malnourished.
3: mildly malnourished with secondary co-morbidities.
4: severely malnourished.
4: severely malnourished.
Many studies have identified the severely malnourished patient as benefiting from preoperative nutrition support with PN. Results from multiple preoperative PN studies of surgical patients have shown no overall reduction in perioperative mortality. However, significant reductions in perioperative complications are achieved in the severely malnourished patient receiving more than 7 days of preoperative PN.
Which of the following is a indication for PN support in an adult cancer patient?
1: Abdominal tumor resulting in an unresolved small bowel obstruction for greater than seven days
2: Metastatic cancer, receiving palliative care
3: Receiving concurrent chemotherapy and radiation therapy
4: Mild malnutrition, scheduled for tumor resection surgery in three days
1: Abdominal tumor resulting in an unresolved small bowel obstruction for greater than seven days
Any adult patient with a gastrointestinal obstruction that precludes oral intake for at least one week may benefit from nutrition support. Mildly malnourished patients do not require PN unless oral intake is anticipated to be inadequate for more than one week. The palliative use of nutrition support in terminally ill cancer patients is rarely indicated. Most side effects of chemotherapy and radiation can be managed without the use of PN. Adult cancer patients scheduled for surgery who are severely malnourished may benefit from PN if the therapy can continue for 7-10 days preoperatively.
When should PN be used in Crohn’s disease?
1: As a primary therapy to rest the bowel
2: Only after failure to tolerate EN
3: To prevent associated malnutrition
4: Preoperatively regardless of nutrition status
2: Only after failure to tolerate EN
Studies comparing PN to EN in patients with Crohn’s disease found no advantage of parenteral over enteral nutrition. Remission rates were similar and there was no evidence that bowel rest with PN had any advantage. Therefore, EN should be used in patients with Crohn’s disease requiring nutrition support therapy. PN should be reserved for Crohn’s patients who do not tolerate EN. Peri-operative specialized nutrition support is indicated in patients with inflammatory bowel disease who are severely malnourished and in whom surgery may be safely postponed.
Current recommendations regarding safe administration of intravenous fat emulsion (IVFE) include
1: IVFE hang time up to 24 hours when included as part of a total nutrient admixture (TNA).
2: IVFE hang time up to 24 hours when administered as an infusion separate from PN.
3: Use of a 0.22 micron filter when administering a TNA to remove microorganisms from a contaminated PN.
4: Use of a 1.2 micron filter when administering a TNA to remove microorganisms from a contaminated PN.
1: IVFE hang time up to 24 hours when included as part of a total nutrient admixture (TNA).
TNA are more likely to be stable for 30 hours at room temperature (25 degrees Celsius) or for 9 days refrigerated (5 degrees Celsius) followed by 24 hours at room temperature. Prolonged storage and/or light exposure can result in degradation of some components of TNA. IVFEs are most stable at their manufactured pH (~6-9), and the addition of acidic dextrose can contribute to TNA instability. Electrolytes, especially positively charged cations calcium and magnesium neutralize the negative charge on the surface of the lipid particle. Commercially available IVFE in the US are stabilized with egg yolk phosphatides providing a mechanical and electrical barrier to particle coalescence. Amino acids offer a protective effect by enhancing the admixtures buffering effect.
Which of the following is the most appropriate distal catheter tip placement of a peripherally inserted central catheter (PICC)?
1: Cephalic vein
2: Superior vena cava
3: Internal jugular vein
4: Supraclavicular vein
2: Superior vena cava
A peripherally inserted central catheter (PICC) is defined as a catheter inserted via peripheral vein whose distal tip lies in the vena cava. The cephalic or basilic vein is often used as the insertion site for PICCs. Central or peripheral access is not defined by the initial point of entry into the vascular system but rather by the position of the distal catheter tip. Central lines are defined as catheters with the distal tip in either the superior or inferior vena cava. Therefore, by definition, a PICC is used as central venous access.
Which of the following is a disadvantage of a peripherally-inserted central catheter (PICC)?
1: High rate of catheter malposition
2: High risk of pneumothorax
3: Requires repeated skin puncture
4: Only available with single lumen
1: High rate of catheter malposition
PICC line disadvantages include: high rate of malposition; limited arm mobility; and limited ability to perform daily self-care due to the availability of only one hand. Advantages of PICC lines include: no risk of pneumothorax; available in single, double, and triple lumens; and repeated skin puncture is not required.
When is it most appropriate to start PN infusion in a patient with a new central venous catheter inserted at the bedside without fluoroscopy?
1: Immediately
2: After auscultating for catheter tip placement
3: After chest X-ray confirms correct placement of catheter tip
4: After ensuring there were no complications with insertion
3: After chest X-ray confirms correct placement of catheter tip
A common complication of central venous catheters inserted at the bedside is catheter misplacement, including pneumothorax. The use of fluoroscopy during catheter insertion allows immediate repositioning of the catheter tip to its correct location in the superior vena cava. PN solutions can be started immediately if the catheter was inserted with the use of fluoroscopy. However, central catheters placed at bedside without fluoroscopy should be radiographically confirmed and documented in the medical record before initial use. Once it has been determined the catheter is in the correct position, PN may be initiated. Auscultation is not a method to determine central venous catheter tip placement.
According to the Centers for Disease Control and Prevention (CDC), which of the following is true regarding peripherally inserted central catheter (PICC) line care?
1: Scheduled replacement is recommended to prevent catheter-related blood stream infections (CRBSIs)
2: Remove the PICC line immediately if fever develops
3: Guidewire exchange should be used when the PICC is a suspected source of infection
4: Remove the PICC line only if it is suspected or known to be the source of infection
Current CDC recommendations: Do not routinely replace central venous catheters, peripherally inserted central catheters, hemodialysis catheters, or pulmonary artery catheters to prevent catheter-related infections. Catheter replacement at scheduled time intervals has not shown a decrease in CRBSI. Do not remove CVCs or PICCs based on fever alone. Clinical judgment should be used to determine appropriateness of catheter removal if infection is evidenced from another site or a noninfectious cause is suspected. Catheter insertion over a guidewire is associated with less discomfort and a lower rate of mechanical complication when compared to percutaneous insertion at a new site, but replacement of temporary catheters during bacteremia should not be done over a guidewire due to source of infection (colonization of skin to insertion site).
