Parenteral Nutrition (PN) may be used to achieve caloric and micro-/macronutrient goals when enteral nutrition (EN) is not tolerated or contraindicated [1]. Depending on the relative proportion of both feeding routes on total delivery of medical nutrition therapy (MNT), PN can both be used to supplement or substitute EN.
Feasibility/Equipment: PN can be administered via peripheral or central venous catheters, according to the osmolality of the PN formulation. Amount and relative proportion of can be calculated from medical records.
Scoring information: The use of PN due to intolerance of EN may be expressed dichotomic (yes/no), or in percentage fraction of the total caloric amount of daily delivered MNT.
Cost: Nursing efforts may be lower when using PN compared to EN. Enhanced recovery and shorter intensive care unit stay may reduce healthcare cost.
Evidence: Certain patient- and disease-related factors influence the decision of using PN due to intolerance of EN: diagnosis malnutrition vs. no malnutrition before ICU admission; the underlying disease itself (e.g., pneumonia with sepsis vs. myocardial infarction; hemodynamic involvement (e.g., shock vs. no shock); the phase of the disease (early vs. late), and the extent of intolerance to EN (e.g., temporarily discontinuous bowel resection vs. trophic nutrition possible) [2]. PN should not be commenced until all “all reasonable strategies to improve EN tolerance have been attempted”, and PN caloric goals should follow the same rules that apply when using EN [3]. Individually optimised energy supplementation with SPN starting 4 days after ICU admission should be considered as a strategy to improve nutrition delivery [4].Care should be taken not to overachieve caloric goals in the early phase of disease, as risk of overfeeding may be larger when using PN, therefore, a personalized approach using indirect calorimetry is recommended [5].
Accuracy / measurement properties:
In a trial comparing supplemental PN combined with EN alone mean energy delivery between day 4 and 8 was 28 kcal/kg per day (SD 5) for the SPN group (103% [SD 18%] of energy target), compared with 20 kcal/kg per day for the EN group (77% [27%]). The authors found a significantly reduced incidence of infection in patients receiving supplemental PN, but this findings could not be replicated [4]. A study including 237 critically ill cardiac surgery patients found that the combined use of EN and PN was started with significant time delay and this practice contributed to excess energy deficits [6]. In a recent prospective observational cohort study, early enteral (aOR 1.06, 95% CI 1.01-1.11) but not early parenteral nutrition (aOR 1.04, 95% CI 0.98-1.11) was significantly associated with mortality on day 28 [7]. In mechanically ventilated adults with at least one organ failure and EN delivery below 80% of estimated energy requirement supplemental PN significantly increased energy delivery when compared to usual care, with no effect on outcomes [8].
References
1. Compher C, Bingham AL, McCall M, Patel J, Rice TW, Braunschweig C, McKeever L: Guidelines for the provision of nutrition support therapy in the adult critically ill patient: The American Society for Parenteral and Enteral Nutrition. JPEN J Parenter Enteral Nutr 2022, 46(1):12-41.
2. Kott M, Hartl WH, Elke G: Enteral vs. parenteral nutrition in septic shock: are they equivalent? Curr Opin Crit Care 2019, 25(4):340-348.
3. Singer P, Blaser AR, Berger MM, Calder PC, Casaer M, Hiesmayr M, Mayer K, Montejo-Gonzalez JC, Pichard C, Preiser JC et al: ESPEN practical and partially revised guideline: Clinical nutrition in the intensive care unit. Clin Nutr 2023, 42(9):1671-1689.
4. Heidegger CP, Berger MM, Graf S, Zingg W, Darmon P, Costanza MC, Thibault R, Pichard C: Optimisation of energy provision with supplemental parenteral nutrition in critically ill patients: a randomised controlled clinical trial. Lancet 2013, 381(9864):385-393.
5. Berger MM, Pichard C: Parenteral nutrition in the ICU: Lessons learned over the past few years. Nutrition 2019, 59:188-194.
6. Stoppe C, Dresen E, Wendt S, Elke G, Patel JJ, McKeever L, Chourdakis M, McDonald B, Meybohm P, Lindner M et al: Current practices in nutrition therapy in cardiac surgery patients: An international multicenter observational study. JPEN J Parenter Enteral Nutr 2023, 47(5):604-613.
7. Pardo E, Lescot T, Preiser JC, Massanet P, Pons A, Jaber S, Fraipont V, Levesque E, Ichai C, Petit L et al: Association between early nutrition support and 28-day mortality in critically ill patients: the FRANS prospective nutrition cohort study. Crit Care 2023, 27(1):7.
8. Ridley EJ, Davies AR, Parke R, Bailey M, McArthur C, Gillanders L, Cooper DJ, McGuinness S, Supplemental Parenteral Nutrition Clinical I: Supplemental parenteral nutrition versus usual care in critically ill adults: a pilot randomized controlled study. Crit Care 2018, 22(1):12.