Parenteral nutrition (PN) is a complex intravenous admixture identified by the Institute for Safe Medication Practices (ISMP) as a high-alert medication.1 In a 2011 survey by the American Society for Parenteral and Enteral Nutrition (ASPEN), respondents noted significant variances in PN utilization and compliance with established PN safety guidelines.2 This survey further revealed that 44% of respondents were not aware of a system to track PN related safety errors within their institution.2

UNC Medical Center (see the SIDEBAR) recognizes that the PN use process is complex, multidisciplinary, and contains numerous opportunities for error, especially when navigating transitions of care. To safeguard patients, analyze the risks presented at each stage of the PN use cycle and create standardized strategies to prevent miscommunication or error (see the FIGURE).

Initiating Parenteral Nutrition

When initiating patients on PN therapy, use validated screening tools or diagnostic criteria to identify patients with existing malnutrition or who are at high risk of developing malnutrition based on disease state and clinical acuity.3 PN use should be restricted to patients who are unable to meet nutritional needs via the oral or enteral route. In general, 7 to 10 days of PN therapy is necessary to see a meaningful difference in clinical outcomes.3 While not exclusive to patients receiving PN therapy, the majority of patients who are receiving PN are at inherent risk of refeeding syndrome due to high use among malnourished patients.4 For in-depth clinical guidance and peer reviewed recommendations, see the resources described in the TABLE.

Support Safe Ordering

A variety of clinicians may be involved in the PN ordering process, including physicians, advanced practice providers, pharmacists, and clinical dietitians. Create policies and procedures dictating who can order PN, the required training and credentialing processes, and ongoing competencies. Ideally, PN orders are submitted via a computerized provider order entry using a standardized order template appropriate for the PN population. Incorporating clinical decision support including soft and hard (catastrophic) limits is vital to enhance safety.

UNC Medical Center’s multidisciplinary nutrition support team (NST) consists of physicians, registered dietitians, and pharmacists responsible for evaluating and ordering PN for all adult patients. Orders are placed using a standardized template within the EHR.

Strengthen Order Verification Processes

A basic order verification process includes a clinical review of PN content, including PN appropriateness, line access, and PN content (fluid, macronutrients, electrolytes, micronutrients, and medications) based on routine laboratory assessment, intake/output, and any other medications that may affect fluid, electrolytes, and nutrition.

Consider conducting a chemical stability and compatibility review in addition to a clinical review. Medications included in the PN preparation should have documented compatibility with PN solutions. Of note, compatibility is influenced by the components of the PN solution including the type of amino acid formulation and the presence and type of lipid injectable emulsion (ILE). The absence of a color change or visible precipitation does not guarantee the clinical efficacy of the added medication. Calcium-phosphate precipitation risk should be effectively mitigated using manufacturer-provided calcium-phosphate solubility curves. Both amino acids and dextrose final concentrations contribute to the calcium-phosphate solubility; train staff to effectively utilize the curves to predict precipitation risk. Compounded PN often varies from the final concentrations reported in the manufacturer data, and a conservative evaluation is warranted to prevent potentially serious consequences.

At our institution, clinical pharmacists perform the order review and verification for adult patients receiving PN on the services they cover. The EHR has been optimized with soft and hard limits to guide the NST members to order safe PN. These limits also guide the review of the PN during the order verification process, highlighting higher-than-standard doses that require additional scrutiny. Catastrophic limits do not allow the clinician to proceed with the order, preventing those errors from reaching the order verification step.

Compounding Considerations

PN may be ordered as a custom compounded admixture or using commercially available multi-chamber bag (MCB) PN solutions. Some institutions may use a mix of both options, particularly during times of shortage. PN may be compounded on-site or outsourced to a compounding pharmacy or a system-wide shared services center. MCB PN solutions are available in a variety of formulations and require activation prior to administration. Select additives such as multivitamins, trace elements, and electrolytes may be added to MCB PN prior to dispensing. Exercise caution when adding electrolytes and refer to manufacturer guidelines and testing. Particularly, calcium chloride is the common salt used in MCB PN, and the addition of phosphate salts will vary compared to standard calcium-phosphate curves. Order transcription may be required depending on the functionality of the EHR to communicate with an automated compounding device (ACD).

Our institution exclusively provides custom PN products. However, MCB PN has been considered for use during times of critical shortage of amino acids, concentrated dextrose, or sterile water for injection. For information on how our institution eliminated PN order transcription errors see the article “Adopt a Multifaceted Approach to PN Safety", published in Pharmacy Purchasing & Products’ April 2024 issue.

Manage Dispensing

Compounded PN products are typically patient-specific. Follow labeling requirements, as for all medications. Determine beyond-use dates (BUDs) based on the documented stability of PN formulations. The recent release of USP <797> indicates a BUD for Category 2 compounded sterile preparations of 4 days at room temperature and 10 days under refrigeration. However, PN BUDs should remain consistent with the previous publication of 30 hours at room temperature and 9 days under refrigeration. The current USP <797> guidelines are based on sterility only and do not take into account the complex compatibility issues of PN admixtures.5

Our facility continues to utilize a BUD of 30 hours at room temperature. We do not currently refrigerate PNs for our adult patients since they are compounded and delivered to the units near the scheduled administration time.

Administration

Although pharmacists are not routinely responsible for PN administration, some questions about medication administration are within the scope of pharmacist responsibilities. An intravenous access device appropriate for the osmolarity of the formulation ordered is essential in preventing venous complications such as phlebitis and extravasation. Administer all PN products using a 1.2 micron filter. In the event of a y-site administration of ILE along with 2-in-1 PN, place the filter below the y-site to capture both the 2-in-1 and ILE products. Y-site administration of additional medications should be discouraged unless line access is severely limited, the medication is essential, and a pharmacist has determined that the medication is compatible with the PN formulation. Compatibility information for custom PN is challenging to interpret given the variety of amino acid and ILE formulations available and tested, whether by the manufacturer or available in reference books.

At our institution, we infuse 2-in-1 PN and separate ILE following the y-site administration technique as described. Two nurses perform an independent double check of the PN formulation label versus the PN formulation order. We discourage co-administration of other medications as a general rule but do allow for co-administration upon pharmacist review of compatibility and physician’s order, if clinically necessary. We use a standard hang time of 2200 daily for adult patients.

Conduct Daily Monitoring

Monitor newly initiated patients daily for signs of refeeding syndrome. Less frequent labs (every other day or two to three times weekly) may be appropriate for longer stay patients who are clinically stable and do not require frequent changes to their formulation. Monitoring parameters should also include weight and clinical progress. An interdisciplinary approach, even in the absence of a formal NST, is essential to providing high quality care for adult patients requiring PN.

Our team reviews daily labs and adjusts PN formulations as indicated. For patients who are clinically stable but unable to be discharged, labs are de-escalated to two to three times per week.

Handling In-Hospital Transfers

Policies and Procedures

In addition to standardized electronic order forms for PN, standardized processes and procedures can aid in safety during transitions of care. For example, institute a daily deadline for all PN order submissions to ensure that orders are prepared by staff who are trained in PN compounding and preparation. Using a standardized hang time can help prevent issues when transitioning between units. Additionally, a standard administration time can prevent confusion when patients transition from unit to unit.

Using custom compounded PN will require different policies and procedures compared to MCB PN. MCB PN use may result in the need to hang multiple bags in a 24 hour period or the need to discontinue and discard the remainder of a bag at the conclusion of a 24 hour hang time. Separate infusion of lipids will also require standardization of y-site infusion or separate infusion.

UNC Medical Center utilizes a daily deadline for adult PN orders of 1500. Labels are subsequently printed in a batch by our sterile processing area pharmacists and technicians for compounding. We have a standard administration time for adult PN and ILE at 2200 daily. We exclusively utilize custom compounded PN, simplifying transfer procedures as only a single bag is dispensed per day.

Hand-Off Communication

Clinician responsibility for PN management varies by institution. Regardless of the parties involved, a standardized hand-off communication tool is essential for a smooth transition. Important documentation includes indication for PN, venous access device, PN start date, estimated or measured nutritional requirements, and nutritional goals.

At our institution, we require a full nutrition follow-up assessment at least once a week for patients undergoing PN therapy. We utilize a daily note that communicates key changes in nutritional provisions (incorporating calories from other sources such as oral or enteral nutrition), fluid requirements, and micronutrient recommendations (for patients with identified deficiencies). We also have a tool used for day-to-day hand-off communication as team members may cross-cover patients on days when the primary clinician is not available.

Hospital Discharge Management

Managing the transfer of patients on PN therapy in the hospital to home or an alternate site of care (eg, long-term acute care hospital, skilled nursing facility) is complex and requires interdisciplinary involvement. Assess the safest discharge option for the patient based on clinical status and acuity as well as insurance coverage and financial responsibility. To be discharged home, a patient and/or caregiver must be capable of home administration of PN in a clean environment. Storage conditions are also an important consideration prior to discharge. Not all alternate sites of care have the capacity to provide PN. Furthermore, some alternate sites of care may have specific preferences regarding custom versus MCB PN, continuous versus cyclic infusion schedules, etc. All of these details are important elements for consideration when creating a safe and efficacious nutrition plan at the time of discharge.6

Creating checklists can be valuable for both communication and clear documentation. ASPEN published a practice tool with detailed steps and key considerations that can be helpful in developing an institution-specific transition of care checklist.6

Prepare for Hospital Admission

It is vital that medication reconciliation be an interdisciplinary effort, and a standardized process led by pharmacists is key to achieving this outcome. Obtaining a copy of the PN formula from the dispensing home or alternate site of care pharmacy should be a standard part of the medication reconciliation process whenever possible. Consider uploading a copy of the PN formula as a reference in the EHR for further documentation. At our institution, a member of the NST contacts the home infusion or alternate site of care pharmacy to obtain a copy of the patient’s most recent PN formulation. A copy is then uploaded into the patient’s chart for reference, the formulation is also referenced in routine nutrition documentation.

In some cases, a patient receiving PN at home (or at an alternate site of care) may not need PN at the time of hospital admission. For example, a patient who is admitted with severe sepsis or bacteremia should have their PN formulation held until blood cultures, empiric antibiotic therapy, and the disposition of central venous access can be determined. Patients may require a “PN holiday” or “line holiday” during which central venous access is removed. During this period, patients may require intravenous fluids in lieu of PN to maintain hydration and serum electrolytes.

If PN therapy is appropriate to resume upon hospital admission, the home PN prescription can serve as a useful reference for pre-hospital fluid, electrolyte, and nutritional requirements. However, it is still vital to perform a full nutrition assessment. For patients admitted to an intensive care unit, consider infusing PN formulations continuously rather than as a cycled regimen. For patients receiving lipid-based medications such as propofol or clevidipine, nutritional ILE should be withheld. Calorie requirements vary based on clinical status (eg, early critical illness, late critical illness, chronic critical illness, or stable/non-critically ill). Surgical interventions or wound healing needs may require an adjustment in protein provisions.

Conclusion

PN is a high-alert medication with multiple opportunities for error throughout the use process. Implementing standardized processes upon admission as well as during the various key points in transitions of care can enhance safety and ensure adequate nutritional provisions for patients who require this complex therapy. Leverage available practice tools that can be adapted to fit the specific institution or site of care.

Sara Bliss, PharmD, BCPS, BCNSP, BCCCP, FASPEN, is a clinical pharmacist, nutrition support, at the University of North Carolina Medical Center in Chapel Hill, North Carolina. Sara received her PharmD from University of Tennessee Health Science Center in Memphis, Tennessee. She completed two years of post-graduate residency training at the University of Arizona Medical Center in Tucson, Arizona. Her second year residency focused on nutrition support pharmacy practice.

References

1. Institute for Safe Medication Practices. ISMP list of high-alert medications in acute care settings. 2024. www.ismp.org/system/files/resources/2024-01/ISMP_HighAlert_AcuteCare_List_010924_MS5760.pdf. Accessed February 24, 2025.
2. Boullata J, Guenter P, and Mirtallo J. A parenteral nutrition use survey with gap analysis. JPEN J Parenter Enteral Nutr. 2013; 37 (2): 212-22.
3. Borthington P, Balint J, Bechtold M, et al. When is parenteral nutrition appropriate? J Parenter Enteral Nutr. 2017;41(3):324-77.
4. da Silva JS, Seres DS, Sabino K, et al. ASPEN consensus recommendations for refeeding syndrome. Nutr Clin Pract. 2020;35(2):178-95.
5. ASPEN. Revised USP 797 Guidelines Now in Effect. www.nutritioncare.org/News/General_News/Revised_USP_797_Guidelines_Now_in_Effect/. Accessed February 26, 2025.
6. Adams SC, Gura KM, Seres DS, et al. Safe care transitions for patients receiving parenteral nutrition. Nutr Clin Pract. 2022;37(3):493-508.
7. Ayers P, Adams S, Boullata J, et al. ASPEN parenteral nutrition safety consensus recommendations. JPEN J Parenter Enteral Nutr. 2014;38(3):296-333.
8. Boullata J, Gilbert K, Sacks G, et al. ASPEN clinical guidelines: parenteral nutrition ordering, order review, compounding, labeling, and dispensing. JPEN J Parenter Enteral Nutr. 2014;38(3):334-77.

SIDEBAR

UNC Medical Center’s PN Program

University of North Carolina Medical Center has more than 900 beds and is part of a statewide health system. We are a tertiary care facility, academic medical center, and level 1 trauma center that primarily functions using a decentralized distribution model with automated dispensing cabinets across the institution. On average, we compound 1,200 PNs per month for both adult and pediatric patients.