4.3 Recommendations from international and internationally recognised guidelines: PN

4.3.1 Key Parenteral nutrition (PN) Guidelines: Summary Tables

Table 4.31 to Table 4.35 summarise the evidence-based international and internationally rec- ognised guidelines on parenteral nutrition (PN) identified from searches of the websites of the relevant professional organisations and the US Department of Health and Human Sciences National Guideline Clearinghouse (www.ahrq.gov). The grading systems used in the guidelines are provided in Table 4.36 to Table 4.45. Links to relevant websites providing further information on the grading of evidence on medical nutrition in clinical guidelines are provided in Table 4.46.

Guidelines focusing on the practical or ethical aspects of administering PN have not been included but are listed in Section 4.3.2 (Guidelines: Theory to practice for enhanced patient care, Table 4.48. Other guidelines that were not identified using the above strategies may exist. In addition, we have only included guidelines in the English language. We would welcome information about other international guidelines that could be included in future editions of the dossier.

Note: The tables that follow include the recommendations relating to PN only, as they appear in the guidelines or documents, from various organisations, covering use of standard formula only. The full documents should be referred to for other information relating to nutritional management, such as screening, assessment, and use of other forms of nutritional support. Terminology relating to PN used within specific guidelines is presented in Table 4.47.

GENERAL

Table 4.31

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – General (parts of guidelines relevant to PN, standard formulas only)

Country	Body	Title	Patient group	Recommendation, guidance, or standard [grade of evidence, where available]
Australia	Dietitians Association of Australia (2019)	Nutrition And Hydration Policy Support Handbook For Acute Adult Inpatient Setting ¹	Adults in hospital	• Artificial nutrition support should be considered when patients cannot adequately or safely meet their nutrition requirements orally. • PN can be used for patients who are unable to tolerate or absorb adequate nutrition support via oral and enteral routes.
England and Wales	National Institute for Health and Care Excellence (NICE) (2006, updated 2017)	Nutrition support in adults: oral nutrition support, enteral tube feeding and parenteral nutrition ²	All patients in the hospital and community	Indications for PN: • Healthcare professionals should consider PN in people who are malnourished or at risk of malnutrition and meet either of the following criteria: inadequate or unsafe oral and/or EN intake a non-functional, inaccessible, or perforated (leaking) GI tract [D(GPP)]. • PN should be introduced progressively and closely monitored, usually starting at no more than 50% of estimated needs for the first 24–48 hours. PN can be withdrawn once adequate oral nutrition or EN is tolerated and nutritional status is stable. Withdrawal should be planned and stepwise, with a daily review of the patient’s progress [D(GPP)]. • PN should be stopped when the patient is established on adequate oral and/or enteral support. There is no minimum duration for PN [D(GPP)].
US	ASPEN (2017)	ASPEN Consensus recommendation. When is parenteral nutrition appropriate? ³	Adult patients	Do not use PN based on medical diagnosis or disease state. • Before starting PN, fully evaluate the feasibility of EN; reserve PN for clinical situations in which adequate EN is not an option. Circumstances where PN is the preferred method of nutrition: • Use PN in patients who are malnourished or at risk for malnutrition when a contraindication to EN exists or the patient does not tolerate adequate EN or lacks sufficient bowel function to maintain or restore nutrition status. Determining when EN is not feasible: • Evaluate clinical factors derived from history, physical examination, and diagnostic evaluations. Time frame for initiating PN: • After 7 days for well-nourished, stable adult patients who have been unable to receive significant (≥ 50% of estimated requirements) oral or enteral nutrients • Within 3–5 days in those who are nutritionally-at-risk and unlikely to achieve desired oral intake or EN • As soon as is feasible for patients with baseline moderate or severe malnutrition in whom oral intake or EN is not possible or sufficient • Delay in a patient with severe metabolic instability until their condition has improved. HPN ^a : • Consider for patients with intestinal failure who are clinically stable and able to receive therapy outside an acute care setting. • Perform a thorough evaluation of medical and psychosocial factors that influence suitability for HPN. • Address financial considerations/insurance coverage and patient responsibilities with patient and caregiver. Initiating HPN: • Establish organisational policies that delineate circumstances in which initiation of PN can take place outside the acute care setting. • Delineate patient-centred eligibility criteria for safely initiating HPN. • Develop strict protocols and procedures for initiating HPN, monitoring response to therapy, and documenting outcomes. • Conduct a comprehensive medical, clinical, and psychosocial assessment of HPN candidates to assess risk factors for adverse events related to initiating PN. • Consider initiating PN at home only when assessment confirms that the benefits greatly outweigh the risks.
US	ASPEN (2011)	Nutrition screening assessment, and intervention in adults ⁴	All patients in hospital and community	Nutrition support intervention is recommended for patients identified by screening and assessment as at risk for malnutrition or malnourished: Grade C (intervention described as “some intervention such as change in diet, EN, PN, or further medical assessment”).
US	ASPEN (2014)	Standards for nutrition support: home and alternate site care ⁵	All patients in homecare environments and alternate care sites*	The route selected to provide nutrition support shall be appropriate to the patient’s medical problems, safety, efficacy, and preference. • When functional, the GI tract is the preferred route for nutrition support therapy.
US	ASPEN (2018)	Standards for nutrition support: adult hospitalized patients ⁶	Adults in hospital	The route selected to provide nutrition support shall be appropriate to the patient’s medical condition and should be assessed periodically for continued appropriateness as well as for its adequacy in meeting goals of the nutrition care plan (see Figure 2 in original guideline).

ᵃHome care is defined as being provided in the traditional home as well as a group home, intermediate care facility, or assisted living facility. Alternate site care facilities can include skilled nursing facilities long-term acute care hospitals, or rehabilitation hospitals.
EN, enteral nutrition; GI, gastrointestinal; GPP, general practice point; HPN, home parenteral nutrition.

OLDER PEOPLE

Table 4.32

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Older People (parts of guidelines relevant to PN, standard formulas only)

Country	Body	Title	Recommendation, guidance, or standard [grade of evidence, where available]
Europe	ESPEN (2009)	Guidelines on parenteral nutrition: geriatrics ⁷	• PN is a safe and effective therapeutic procedure, provided that it is provided by an experienced team. Age per se is not a reason to exclude patients from PN [Grade C]. • PN is indicated and may allow adequate nutrition in patients who cannot meet their nutritional requirements via the enteral route and should be limited to situations when EN is contraindicated or poorly tolerated [Grade C]. • PN support should be instituted in the older person facing a period of starvation of more than 3 days when oral nutrition or EN is impossible or has been or is likely to be insufficient for more than 7–10 days [Grade C]. • PN is a useful method of nutritional support in older malnourished patients but is less often justified in geriatric patients than EN or oral nutritional supplements [Grade B]. • Indications for PN are similar in younger and older adults in the hospital and at home and are limited to situations when EN is contraindicated or poorly tolerated [Grade B].
Europe	ESPEN (2022)	ESPEN practical guideline: Clinical nutrition and hydration in geriatrics ⁸	• Older persons with reasonable prognosis (expected benefit) shall be offered PN if oral and enteral intakes are expected to be impossible for more than three days or expected to be below half of the energy requirements for more than one week, in order to meet nutritional requirements and maintain or improve nutritional status. [Grade GPP, strong consensus 100%]
Europe	The German Association for Nutritional Medicine (2009)	Lipid emulsions - Guidelines on Parenteral Nutrition ⁹	The recommended daily dose for parenteral lipids in adults is 0.7–1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l).
Unspecified (panel of international experts)	The Lipids in PN Summit (2025)	Lipids in parenteral nutrition – expert consensus statements: Translating guidelines into clinical practice ¹⁰	• ILEs are an integral part of parenteral nutrition. Originally, ILEs were included as an energy-dense source of calories and provided EFAs. • In adult medical and surgical ICU patients requiring parenteral nutrition, ILEs are an integral part of parenteral nutrition. • The use of ILEs containing fish oil should be considered during the first week of ICU admission in adult patients requiring parenteral nutrition, including surgical and critically ill patients, based on biological plausibility and associated clinical benefits.⁹ In adult medical and surgical ICU patients, the total lipid dose is, in general, up to 1.5g lipids/kg/day (including non-nutritive lipid sources such as propofol). A minimum ILE dose should be given to prevent EFA deficiency.

The grading system for recommendations is summarised in Table 4.37 (before 2015) and Table 4.38 (2015 onwards). EN, enteral nutrition; ESPEN, European Society for Parenteral and Enteral Nutrition; PN, parenteral nutrition.

CHILDREN

Table 4.33

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Children (parts of guidelines relevant to PN, standard formulas only)

Country	Body	Title	Recommendation, guidance, or standard [grade of evidence, where available]
Europe	European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and ESPEN, supported by the European Society of Paediatric Research	Guidelines on paediatric parenteral nutrition (2005) ¹¹	• Timing for initiation of PN depends on individual circumstances and the age and size of the infant or child. • In small preterm infants, starvation for just 1 day may be detrimental; thus, PN must be instituted shortly after birth if it is clear that enteral feeds will not be tolerated soon. • In older children and adolescents, longer periods of inadequate nutrition (up to about 7 days) may be tolerated, depending on age, nutritional status, and the disease, surgery, or medical intervention.
Europe	ESPEN, ESPGHAN, and European Cystic Fibrosis Society (ECFS) (2024)	Guidelines on nutrition care for infants, children, and adults with cystic fibrosis ¹²	• The use of PN may be reserved for exceptional cases when EN is not possible or has failed. [Grade 0- Strong consensus 100 % agreement] • Formulation choice of total PN may favour a lipid anti-inflammatory profile including medium chain triglycerides (MCT) and fish oil to minimise the risk of cholestasis (0). [Grade GPP/0- Strong consensus 100 % agreement]
International	Surviving Sepsis Campaign (2020)	Surviving Sepsis Campaign International Guidelines for the Management of Septic Shock and Sepsis-Associated Organ Dysfunction in Children ¹³	• We suggest enteral nutrition as the preferred method of feeding and that parenteral nutrition may be withheld in the first 7 days of PICU admission in children with septic shock or other sepsis-associated organ dysfunction (weak recommendation, moderate quality of evidence). Our recommendation to withhold PN in the first 7 days of PICU admission is of moderate certainty and must be explored further using pragmatic timing for PN in the first week, particularly in severely malnourished patients and neonates.
US	ASPEN (2017)	Consensus recommendation. When is parenteral nutrition appropriate? ³	Use of PN is based on medical diagnosis or disease state: • Neonatal: Consider PN in the critical care setting, regardless of diagnosis, when EN is unable to meet energy requirements for energy expenditure and growth. • Paediatric: Use PN when the GI tract is not functional or cannot be accessed or when nutrient needs for growth are greater than can be provided through oral intake or EN support alone. Circumstances where PN is the preferred method of nutrition (neonatal and paediatric): • Initiate PN for total or supplemental nutrient provision if EN is not feasible or is not sufficient to meet total nutrient needs. Determining when EN is not feasible (neonatal and paediatric): • Initiate PN and withhold EN when a clear contraindication to EN exists, such as intestinal injury and perforation. • Assess intestinal function, perfusion, and overall hemodynamic stability when evaluating readiness for EN rather than relying on strict adherence to a list of contraindications, such as the presence of umbilical catheters or use of vasoactive medications. Time frame for initiating PN: • Neonatal: begin PN promptly after birth in very low birth weight infants (< 1500 g); there are insufficient data to suggest a specific time frame for initiation of PN in more mature preterm infants or critically ill term neonates. • Paediatric: For the infant, child, or adolescent with a self-limited illness, it is reasonable to delay starting PN for 1 week. However, initiate PN within 1–3 days in infants and within 4–5 days in older children and adolescents when it is evident that they will not tolerate full oral intake or EN for an extended period. HPN (paediatric) • Consider HPN for carefully selected, clinically stable paediatric patients who are expected to require PN for an extended period. • Discharge patients to the care of a paediatric homecare team and infusion provider with paediatric experience. • Do not initiate PN in the home setting; patients should be admitted to hospital for initiation of PN.
US	Society of Critical Care Medicine (SCCM) and ASPEN (2017)	Guidelines for the provision and assessment of nutrition support therapy in the pediatric critically ill patient ¹⁴	Guidelines relate to critically ill paediatric patients (aged > 1 month and < 18 years) expected to spend > 2–3 days in a PICU, admitting medical, surgical, and cardiac patients. Indication for and optimal timing of PN in critically ill children: • On the basis of a single RCT, we do not recommend the initiation of PN within 24 h of PICU admission [quality of evidence: moderate; GRADE recommendation: strong]. Role of PN as a supplement to inadequate EN: • For children tolerating EN, we suggest stepwise advancement of nutrient delivery via the enteral route and delaying PN. Based on current evidence, the role of SPN to reach a specific goal for energy delivery is not known. • The time when PN should be initiated to supplement insufficient EN is unknown. The threshold for and timing of PN initiation should be individualised. Based on a single RCT, SPN should be delayed until 1 week after PICU admission for patients with normal baseline nutrition state and low risk of nutrition deterioration. • On the basis of expert consensus, we suggest PN supplementation for children who are unable to receive any EN during the first week in the PICU. For patients who are severely malnourished or at risk of nutrition deterioration, PN may be supplemented in the first week if they are unable to advance past low volumes of EN [Quality of evidence: low; GRADE recommendation: weak].
US	ASPEN	Nutrition support of the critically ill child (2009) ¹⁵	• In critically ill children with a functioning GI tract, EN should be the preferred mode of nutrient provision, if tolerated [Grade C].
US	ASPEN	Standards for nutrition support: pediatric hospitalized patients (2013) ¹⁶	• PN should be used when the GI tract is not functional or cannot be accessed, or the patient’s nutrient needs are greater than can be met through the GI tract.

ASPEN, American Society for Parenteral and Enteral Nutrition, ECSF, European Cystic Fibrosis Society; EN, enteral nutrition; GI, gastrointestinal; HPN, home parenteral nutrition; PICU, pediatric inten- sive care unit; PN, parenteral nutrition; RCT, randomized controlled trial; SPN, supplemental parenteral nutrition

SPECIFIC DISEASES

Table 4.34

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Specific Diseases and Conditions (parts of guidelines relevant to PN presented here, standard formulas only)

Patient Group	Country & Body	Title	Recommendation, Guidance, or Standard [Grade of Evidence]
Critical Illness	Canada Canadian Critical Care Society (CCCS) and Canadian Critical Care Trials Group (CCCTG) (2015)	Canadian Critical Care Nutrition Clinical Practice Guidelines¹⁷	Use of EN vs PN: • When considering nutrition support for critically ill patients, we recommend EN over PN in patients with an intact gastrointestinal tract. Combination PN and EN: • For critically ill patients starting on EN, we recommend that PN is not started at the same time as EN. In the patient who is not tolerating adequate EN, there are insufficient data to put forward a recommendation about when PN should be initiated. Practitioners will have to weigh the safety and benefits of initiating PN on a case-by-case basis. We recommend that PN is not started in critically ill patients until all strategies to maximise EN delivery (such as small bowel feeding tubes, motility agents) have been attempted. Early vs delayed SPN: • We strongly recommend that early SPN and high IV glucose are not used in unselected critically ill patients (i.e., low-risk patients with short stay in ICU). In the patient who is not tolerating adequate EN, there are insufficient data to put forward a recommendation about when PN should be initiated; practitioners will have to weigh the safety and benefits of initiating PN in patients on a case-by-case basis. PN vs standard care: • We recommend that PN is not used routinely in critically ill patients with an intact gastrointestinal tract; early PN should be considered in nutritionally high-risk patients with a relative contraindication to early EN.
Critical Illness	Europe ESPEN (2023)	ESPEN practical and partially revised guideline: Clinical nutrition in the intensive care unit¹⁸	• In case of contraindications to oral and EN, PN should be implemented within three to seven days. [Grade B, consensus 89%] • Early and progressive PN can be provided instead of no nutrition in case of contraindications for EN in severely malnourished patients. [Grade 0, strong consensus, 95%] • In patients who do not tolerate full-dose EN during the first week in the ICU, the safety and benefits of initiating PN should be weighed on a case-by-case basis. [Grade GPP, strong consensus, 96%] • In non-intubated patients with dysphagia and a very high aspiration risk, postpyloric EN or, if not possible, temporary PN during swallowing training with removed nasoenteral tube can be performed. [Grade GPP, strong consensus, 92%] • In the case of an unrepaired anastomotic leak, internal or external fistula, or if distal feeding access is not achieved, EN should be withheld, and PN may be commenced. [Grade GPP, strong consensus, 100%] • Early and progressive EN should be used in septic patients after hemodynamic stabilisation. If contraindicated, EN should be replaced or supplemented by progressive PN. [Grade GPP, strong consensus 94%] • The administration of intravenous lipid emulsions should generally be a part of PN. [Grade GPP, strong consensus, 100%] • Parenteral lipid emulsions enriched with EPA and DHA (Fish oil dose 0.1–0.2 g/kg/d) can be provided in patients receiving PN. [Grade 0, strong consensus, 100%]
Critical Illness	US ASPEN (2016)	Guidelines for the provision and assessment of nutrition support therapy in the adult critically ill patient¹⁹ Specific patient populations: organ failure (pulmonary, renal, and hepatic), acute pancreatitis, surgical subsets (trauma, traumatic brain injury, open abdomen, and burns), sepsis, postoperative major surgery, chronically critically ill, obese critically ill, and end-of-life situations	When to initiate PN in the adult critically ill patient at low nutrition risk: • We suggest that, in the patient at low nutrition risk (e.g., NRS 2002 ≤ 3 or NUTRIC score ≤ 5), exclusive PN be withheld over the first 7 days following ICU admission if the patient cannot maintain volitional intake and if early EN is not feasible. [Quality of evidence: very low] When to initiate PN in the critically ill patient at high nutrition risk: • Based on expert consensus, in the patient determined to be at high nutrition risk (e.g., NRS 2002 ≥ 5 or NUTRIC score ≥ 5) or severely malnourished, when EN is not feasible, we suggest initiating exclusive PN as soon as possible following ICU admission. Optimal timing for initiating supplemental PN (SPN): • We recommend that, in patients at either low or high nutrition risk, use of SPN be considered after 7–10 days if EN alone is unable to meet > 60% of energy and protein requirements. Initiating SPN earlier than this in critically ill patients receiving some EN does not improve outcomes and may be detrimental. [Quality of evidence: moderate]
Critical Illness	US ASPEN (2022)	Guidelines for the provision of nutrition support therapy in the adult critically ill patient: The American Society for Parenteral and Enteral Nutrition²⁰	In adult critically ill patients who are candidates for EN, does similar energy intake by PN vs EN as the primary feeding modality in the first week of critical illness impact clinical outcomes? There was no significant difference in clinical outcomes between early exclusive PN and EN during the first week of critical illness. As PN was not found to be superior to EN and no differences in harm were identified, we recommend that either PN or EN is acceptable. [Evidence Grade: High; Strength of Grade recommendation: Strong] In adult critically ill patients receiving EN, does provision of SPN, as compared with no SPN during the first week of critical illness, impact clinical outcomes? There was no significant difference in clinical outcomes. Based on findings of no clinically important benefit in providing SPN early in the ICU admission, we recommend not initiating SPN prior to day 7 of ICU admission. [Evidence Grade: High; Strength of Grade recommendation: Strong]
Critical Illness	International Surviving Sepsis Campaign (2012)	International guidelines for management of severe sepsis and septic shock (2012)²¹	Nutrition: We suggest intravenous glucose and EN rather than TPN alone or PN in conjunction with enteral feeding in the first 7 days after a diagnosis of severe sepsis/septic shock. [Grade 2B]
Critical Illness	England & Wales National Institute for Health and Care Excellence (NICE) (2006, updated 2017)	Nutrition support in adults: oral nutrition support, enteral tube feeding and parenteral nutrition²	If intestinal tolerance persistently limits enteral tube feeding in surgical or critical care patients, PN should be used to supplement or replace enteral tube feeding. [Grade B]
Renal Failure	US ASPEN (2017)	Consensus recommendation: when is parenteral nutrition appropriate?³	Intradialytic PN (IDPN), global recommendations: Do not use as the sole source of nutrition intervention in malnourished patients with CKD. Consider for adult and paediatric patients with CKD who are malnourished and unable to tolerate adequate oral intake or EN.
Renal Failure	US ASPEN (2010)	Nutrition support in adult acute and chronic renal failure²²	This guideline does not contain specific recommendations on when to initiate PN. Patients with renal failure who require nutrition support therapy should receive EN if intestinal function permits. [Grade E]
Renal Failure	US National Kidney Foundation (2020)	Kidney Disease Outcomes Quality Initiative (KDOQI) clinical practice guidelines for nutrition in chronic renal failure: 2020 update²³	In adults with CKD with protein energy wasting, we suggest a trial of TPN for CKD 1-5 patients (2C) and IDPN for CKD5D on MHD patients (2C), to improve and maintain nutritional status if nutritional requirements cannot be met with existing oral and enteral intake. [Grade 2C]
Renal Failure	Europe European Renal Association – European Dialysis and Transplant Association (2007)	European best practice guideline on nutrition²⁴	When intensive dietary support, oral supplements, and EN have failed, a course of PN is recommended. [Evidence level IV] IDPN is recommended in malnourished patients only if spontaneous nutrient intake is > 20 kcal/kg IBW and 0.8 g protein/kg IBW/day. Otherwise, TPN infused over the entire day is indicated. [Opinion]
Renal Failure	Europe ESPEN (2024)	ESPEN practical guideline on clinical nutrition in hospitalized patients with acute or chronic kidney disease²⁵	• Intradialytic parenteral nutrition (IDPN) shall be applied in malnourished non-critically ill hospitalised patients with CKD and KF on haemodialysis, or the same patients if at risk of malnutrition who fail to respond or do not tolerate ONS or EN. [Grade A, strong consensus 100%] • EN, PN, or EN and PN shall be given to critically and noncritically ill hospitalised patients with AKI/AKD, CKD, CKD with KF unable to achieve at least 70% of macronutrient requirements with oral nutrition. [Grade A, strong consensus 96%] • In case of contraindications to oral and EN, PN should be implemented within three to seven days. [Grade B, consensus 89% • Early and progressive PN can be provided instead of no nutrition in case of contraindications for EN in severely malnourished patients. [Grade 0, strong consensus 95%]
Renal Failure	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: adult renal failure²⁶	Acute renal failure (ARF): • The indications for and contraindications to PN in ARF are comparable to those in other critically ill patients (see ICU guidelines). • PN is appropriate in ARF when the GI tract cannot be used for enteral feeding, or when EN is not enough to reach nutrient intake goals. [Grade C] Chronic renal failure (CRF): • Conservatively treated patients with CKD seldom need PN. Potential indications of PN in CKD patients are similar to the indications for PN in non-renal patients. Malnourished CKD patients requiring nutritional support should only be considered for PN when ONS and EN are impossible or fail to reach nutritional goals. Special attention should be given to CKD requiring PN during perioperative periods [Grade C]. • When nutritional requirements cannot be met by dietary intake (with or without ONS), in combination with EN or by the enteral route alone, the goals of PN in CKD patients are (a) prevention and treatment of PEW leading to cachexia; (b) ensuring provision of optimal energy, essential nutrients and trace elements; and (c) attenuation of CKD progression through protein or phosphate restriction [Grade C]. Patients on maintenance haemodialysis (HD): • In acutely ill patients with CKD on dialysis, the decision to use PN should be based on the same criteria as in ARF patients. • In non-acutely ill malnourished HD patients with mild PEW as defined by insufficient spontaneous intake, dietary counselling, and, if necessary, ONS should be prescribed. • In patients exhibiting severe PEW, with spontaneous intake > 20 kcal/day, dietary counselling and ONS should be prescribed; IDPN is indicated in patients unable to comply with ONS; EN can be necessary when ONS or IDPN fail to improve nutritional status. • In patients exhibiting severe PEW, with spontaneous intake < 20 kcal/day, or in stress conditions: both ONS and IDPN are generally unable to provide satisfactory nutritional supply and are not recommended; daily nutritional support is necessary, and EN should be preferred to PN; central venous PN is indicated when EN is impossible or insufficient. Patients on continuous ambulatory peritoneal dialysis (CAPD): • Intravenous PN has been poorly investigated in CAPD patients. Current data suggest that PN should be limited to malnourished and stressed CAPD patients, or patients with severe encapsulating peritonitis, when nutritional requirements cannot be ensured by oral or enteral routes. [Grade C] • In acutely ill patients with CKD on dialysis, the decision to use PN should be the same as in ARF patients. [Grade C] • In CAPD patients presenting with mild PEW as defined by insufficient spontaneous intake, dietary counselling, and, if necessary, ONS should be prescribed. [Grade C] • In patients exhibiting severe PEW, with spontaneous intake > 20 kcal/day: dietary counselling and ONS should be prescribed; IPPN may be considered in patients unable to comply with ONS; EN can be necessary when ONS are unable to improve nutritional status. [Grade C] • In patients exhibiting severe PEW, with spontaneous intakes < 20 kcal/day, or in stress conditions: daily nutritional support is necessary and EN should be preferred to PN; central venous PN is indicated when EN is impossible or insufficient. [Grade C] • In acutely ill patients with CKD on dialysis, the goal of PN is to reduce protein catabolism and nutritional depletion-associated morbidity and mortality. In chronically undernourished CAPD patients, IPPN aims to improve quality of life and to reduce PEW-related complications, hospitalisation rate, and mortality. [Grade C]
Chronic Heart Failure	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: cardiology and pneumology²⁷	• Although there is no evidence from well-designed studies, PN is recommended to stop or reverse weight loss in patients with evidence of malabsorption, on the basis that it improves outcome in other similar conditions and there is a plausible physiological argument for it. [Grade C] • Currently, there is no indication for PN in the prophylaxis of cardiac cachexia. [Grade C]
COPD	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: cardiology and pneumology (2009)²⁷	There is limited evidence that COPD patients intolerant of EN profit from PN. However, small studies suggest that, in combination with exercise and anabolic pharmacotherapy, PN has the potential to improve nutritional status and function. [Grade C]
Gastrointestinal Disease	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: gastroenterology²⁸	Crohn’s disease (CD): • Improvement of growth: PN should be used if enteral feeding cannot be tolerated. [Grade B] • Primary therapy for active CD: PN should not be used as a primary treatment in patients with inflammatory luminal CD. [Grade A] • Perioperative nutrition: As for other underlying diseases, PN in the perioperative period should be given to prevent or treat malnutrition in patients who are not likely to be fed orally and/or enterally. • Maintenance of remission: PN is not recommended for maintenance of remission. [Grade B] • PN is indicated when nutrition cannot be maintained via the intestine in the following situations [all Grade B]: Obstructed bowel not amenable to feeding tube placement beyond the obstruction Short bowel resulting in severe malabsorption or fluid and electrolyte loss, which cannot be managed enterally Severe dysmotility making enteral feeding impossible A leaking intestine from high-output intestinal fistula, or surgical anastomotic breakdown Patient intolerant of EN whose nutrition cannot be maintained orally Unable to access the gut for enteral feeding. Ulcerative colitis (UC): • Except in complicated UC or in the perioperative period, PN is not indicated to treat undernutrition in UC. [Grade B] • PN is indicated as an adjuvant to other forms of medical treatment – but not as a primary treatment – and is used in severe attacks of UC only when EN is not tolerated or is contraindicated (e.g., impending or established toxic megacolon, colonic perforation, massive colonic bleeding). [Grade B] • PN does not have any role in the maintenance of remission in UC. [Grade B] Role of PN in short bowel (intestinal failure): • Post-operative phase: Most patients with a short bowel require PN for the first 7–10 days after resection, but not necessarily in isolation. [Grade C] • Adaption phase: Appropriate EN and/or oral nutrition should be initiated as soon as possible and progressively increased depending on the tolerance of the gut and the patient. • Maintenance/Stabilisation phase: According to the length of residual small bowel and type of anatomy (preserved colon or not), patients with short bowel may need long-term PN. [Grade B] In some, the main problem relates to stabilizing water and electrolyte balance. In some (usually with a retained colon) appropriate adaptive hyperphagia, and intestinal adaptation may improve nutritional status sufficiently such that PN can be reduced or stopped. [Grade B]
Gastrointestinal Disease (IBD)	Europe ESPEN (2023)	ESPEN Guideline: Clinical nutrition in inflammatory bowel disease (IBD) (2023)²⁹	IBD • If oral feeding is not sufficient, then EN can be considered as supportive therapy. EN using formulas or liquids usually takes preference over PN unless it is completely contraindicated. [Grade 0; Strong consensus 96% agreement.] • PN shall be performed in IBD (i) when oral nutrition or EN is not sufficiently possible (e.g. when the gastrointestinal tract is dysfunctional or in patients with CD with short bowel), (ii) when there is an obstructed bowel where there is no possibility of placement of a feeding tube beyond the obstruction or where this has failed, or (iii) when other complications occur such as an anastomotic leak or a high output intestinal fistula. [Grade GPP; Strong consensus 100% agreement]. • PN may usually not be used in UC unless the patient cannot be fed effectively otherwise. [Grade 0; Strong consensus 95% agreement] • In surgical patients, medical nutrition therapy (EN and/or PN as indicated) should be initiated without delay if the patient is malnourished at the time of surgery or if oral diet cannot be adequately recommenced within seven days after surgery. [Grade GPP; Strong consensus 96% agreement]. • If the energy and/or nutrient requirements cannot be met by oral and enteral intake alone (<50% of the needs) for more than seven days, a combination of EN and PN is recommended. [Grade GPP; Strong consensus 100% agreement] • PN shall be used as the only intervention only if EN is impossible (e.g., because of the absence of access, severe vomiting, or diarrhoea) or contraindicated (e.g., because of intestinal obstructions or ileus, severe shock, intestinal ischemia). [Grade A; Strong consensus 100% agreement]. • In patients with CD with prolonged gastrointestinal failure (such as patients in whom resection has created a short bowel), PN is mandatory and lifesaving at least in the early stages of intestinal failure, and therefore, PN should be performed in such conditions. [Grade GPP; Strong consensus 95% agreement].
Chronic Intestinal Failure	Europe ESPEN (2023)	ESPEN guideline on chronic intestinal failure in adults – Update 2023²⁸	Chronic intestinal failure • HPN should be prescribed as the primary and life-saving therapy for patients with transient-reversible or permanent-irreversible CIF. [Grade B - Strong consensus 100% agreement]
Celiac Disease	US ACG (2013)	ACG: Clinical guidelines: diagnosis and management of celiac disease ³¹	Celiac Disease • Patients with refractory celiac disease should be monitored closely and receive aggressive nutritional support, including PN whenever indicated. (Strong recommendation, high level of evidence)
Celiac Disease	US ACG (2023)	ACG: Clinical guidelines: diagnosis and management of celiac disease³²	Celiac Disease • Parenteral nutritional support is often needed in patients with refractory celiac disease.
Gastrointestinal Disease (Intestinal Failure)	Europe ESPEN (2016)	Management of acute intestinal failure: a position paper from the European Society for Clinical Nutrition and Metabolism (ESPEN) Special Interest Group³³	Intestinal failure (IF): • Although enteral nutrition has proven to be the most beneficial in almost all patient populations, it is relatively rare that it is sufficient in acute IF/enterocutaneous fistula (ECF) individuals because of the compromised integrity of the GI tract. Therefore, PN often represents the main option, alone or in association with EN.
Gastrointestinal Disease (Chronic Intestinal Failure)	Europe ESPEN (2016)	ESPEN guidelines on chronic intestinal failure in adults³⁴	HPN is the primary treatment for chronic IF: • We recommend that patients selected for HPN have confirmed IF that, despite maximal medical therapy, would lead to deterioration of nutrition and/or fluid status. [Grade of evidence: very low; strength of recommendation: strong] • We suggest the use of enteral tube feeding in combination with oral feeding in patients with chronic IF with a low level of HPN dependence (i.e., B1 category of clinical classification) and in whom the expected gain with tube feeding could allow them to wean off HPN. [Grade of evidence: low; strength of evidence: weak] • We recommend that HPN is not delayed in malnourished patients with chronic intestinal pseudo-obstruction (CIPO) who have chronic GI motility dysfunctions and oral/EN is obviously inadequate. [Grade of evidence: very low; strength of evidence: strong] • We recommend HPN is not delayed in malnourished patients with radiation enteritis if oral nutrition/enteral tube feeding is obviously inadequate. [Grade of evidence: very low; strength of evidence: strong] • We recommend HPN as the primary treatment for patients with chronic IF and the early referral of patients to intestinal rehabilitation centres with expertise in both medical and surgical treatment, to maximise the opportunity of weaning off HPN, to prevent HPN failure, and to ensure timely assessment of candidacy for intestinal transplantation. • We suggest the use of EN in combination with oral feeding in patients with chronic IF with a low level of HPN dependence (i.e., B1 category of clinical classification) and in whom the expected gain with EN could allow them to wean off HPN. [Grade of evidence: low; strength of recommendation: weak]
Liver Disease	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: hepatology³⁵	Alcoholic steatohepatitis: • Immediate commencement of PN is indicated in patients with moderate or severe malnutrition who cannot be fed sufficiently orally or enterally. [Grade A] Liver cirrhosis: • Immediate commencement of PN is indicated in moderately or severely malnourished patients who cannot be sufficiently nourished orally or enterally. [Grade C] • Patients who can be fed sufficiently by the oral or enteral route but who have to abstain from food temporarily for more than 12 h (including nocturnal fasting) should be given IV glucose (2–3 g/kg/d). When this fasting period lasts longer than 72 h, TPN is required. [Grade C] • PN should be considered in patients with unprotected airways and encephalopathy when cough and swallow reflexes are compromised. [Grade C] • Early postoperative (additional) PN after surgery is indicated if patients cannot be nourished sufficiently by the oral/enteral route. [Grade A] • After liver transplantation, patients should receive early postoperative nutrition; PN is second choice to EN. [Grade C] Acute liver failure: • As in other critically ill patients, artificial nutrition is indicated when the patient is unlikely to resume normal oral nutrition within the next 5–7 days irrespective of current nutritional state. PN is helpful in patients who cannot be fed adequately by EN. [Grade C]
Liver Disease	Europe ESPEN (2020)	ESPEN practical guideline: Clinical nutrition in liver disease³⁶	Acute liver failure: • In malnourished ALF patients, enteral nutrition (EN) and/or PN should be initiated promptly, as in other critically ill patients. [Grade GPP, strong consensus 96%] • PN should be used as second-line treatment in patients who cannot be fed adequately by oral and/or EN. [Grade GPP, consensus 90%] Alcoholic steatohepatitis PN shall be commenced immediately in moderately or severely malnourished patients with severe ASH who cannot be nourished sufficiently by oral and/or enteral route. [Grade GPP, strong consensus 100%] PN should be considered in patients with unprotected airways and hepatic encephalopathy when cough and swallow reflexes are compromised or EN is contraindicated or impracticable. [Grade GPP, majority agreement 72%] Non-alcoholic fatty liver disease / Non-alcoholic Steatohepatitis: • EN or PN shall be administered in NAFL/NASH patients during severe intercurrent illness, when oral nutrition alone is inadequate or impossible or contraindicated. [Grade GPP, strong consensus 96%] Liver cirrhosis: • PN should be used in cirrhotic patients in whom oral and/or EN are ineffective or not feasible. [Grade B, strong consensus 100%]
Acute and Chronic Pancreatitis	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: pancreas³⁷	Acute pancreatitis: • All patients who the clinician decides require nutritional support is indicated should have this commenced by the enteral route; PN is indicated only in patients who are unable to tolerate targeted requirements, that is, when the gut has failed or administration of EN is impossible for other reasons (e.g. prolonged ileus, complex pancreatic fistulae, abdominal compartment syndrome). [Grade B] • As EN tolerance increases, the volume of PN should be decreased. When tolerated, EN is associated with improved outcomes compared with PN. [Grade A] • PN does not significantly stimulate pancreatic secretion and has no adverse effects on pancreatic function. [Grade A] Chronic pancreatitis: • Malnutrition is frequent because of pain-induced anorexia and continuing alcohol abuse. Resting energy expenditure may also be increased. PN may be indicated in patients with gastric outlet obstruction secondary to duodenal stenosis and in those with complex fistulating disease. [Grade C]
Acute and Chronic Pancreatitis	Europe ESPEN (2024)	ESPEN practical guideline on clinical nutrition in acute and chronic pancreatitis³⁸	Acute pancreatitis: • In patients with acute pancreatitis and inability to feed orally, enteral nutrition shall be preferred to parenteral nutrition. [Grade A, strong consensus, 97%] • PN should be administered in patients with acute pancreatitis who do not tolerate enteral nutrition or who are unable to tolerate targeted nutritional requirements, or if contraindications for EN exist. [Grade GPP, strong consensus, 97%] • PN is indicated in patients undergoing minimally invasive necrosectomy who do not tolerate EN or who are unable to tolerate targeted nutritional requirements, or if there exist contraindications for enteral nutrition. [Grade GPP, strong consensus, 94%] • In patients with severe acute pancreatitis and intraabdominal pressure > 20 mmHg or in the presence of acute compartment syndrome, enteral nutrition should be (temporarily) stopped and parenteral nutrition should be initiated. [Grade GPP, strong consensus, 94%] • In patients with severe acute pancreatitis and open abdomen enteral nutrition should be administered, at least in a small amount. If required for achievement of nutritional requirements, supplementary or total parenteral nutrition should be added. [Grade B, strong consensus, 97%] Chronic pancreatitis: • Parenteral nutrition may be indicated in patients with gastric outlet obstruction and in those with complex fistulating disease, or in case of intolerance of enteral nutrition. [Grade GPP, strong consensus, 100%]
Acute and Chronic Pancreatitis	US American College of Gastroenterology (ACG) (2023)	Management of acute pancreatitis (2023)³⁹	• Parenteral nutrition should be avoided, unless the enteral route is not possible, not tolerated, or not meeting the caloric needs.
Acute and Chronic Pancreatitis	International International Consensus Guideline Committee	International consensus guidelines for nutrition therapy in pancreatitis (2012)⁴⁰	• Use PN if nutrition therapy is indicated but EN is contraindicated or not well tolerated. [Grade A: Platinum]
Cystic Fibrosis	Europe ESPEN	ESPEN Guidelines on Nutrition in Cystic Fibrosis¹²	• The use of PN may be reserved for exceptional cases when EN is not possible or failed. [Grade 0 - Strong consensus 100% agreement] • Infants with meconium ileus requiring surgical intervention (approx. 70%) should initially be supported by PN to support their growth. (GPP) • PN is not routinely recommended as a method of nutritional support for people with cystic fibrosis due to the benefits of EN, risk of complications, difficulty of administration, and high cost. • PN may be essential as short-term nutritional support following intestinal resection in infants presenting with MI and children and adults following major gastrointestinal surgery, where EN is not possible. It may also be beneficial for severely compromised patients awaiting transplantation.
Surgery	Europe ESPEN (2021)	ESPEN guideline: clinical nutrition in surgery⁴¹	Indication for nutritional therapy: • If the energy and nutrient requirements cannot be met by oral and enteral intake alone (<50% of caloric requirement) for more than seven days, a combination of enteral and PN is recommended (GPP). PN shall be administered as soon as possible if nutrition therapy is indicated and there is a contraindication for EN, such as in intestinal obstruction. (A) [Grade GPP/A; strong consensus 100% agreement] Preoperative PN: • Preoperative PN shall be administered only in patients with malnutrition or severe nutritional risk where energy requirement cannot be adequately met by EN(A). A period of 7 to 14 days is recommended (0). [Grade A/0 - strong consensus 100% agreement] After organ transplant: • If necessary, EN and PN should be combined. Long-term nutritional monitoring and qualified dietary counselling are recommended for all transplants. [Grade GPP; strong consensus 100% agreement] Bariatric surgery: • PN is not required in uncomplicated bariatric surgery. [Grade 0; strong consensus 100% agreement]
Surgery	Europe European Society of Coloproctology (2016)	Consensus on the surgical management of intestinal failure in adults⁴²	• PN should be started as soon as it is anticipated that EN will be unable to meet the patient’s nutritional and metabolic needs. [Level of evidence: 5] • HPN is the primary therapeutic option for intestinal failure, as it is associated with better or comparable long-term survival compared with intestinal transplantation. [Level of evidence: 5]
Surgery	England & Wales National Institute for Health and Care Excellence (2006, updated 2017)	NICE: Nutrition support in adults: oral nutrition support, enteral tube feeding and parenteral nutrition²	• Perioperative SPN should be considered in malnourished surgical patients who have an inadequate or unsafe intake via the oral and/or enteral routes or a non-functional, inaccessible, or perforated (leaking) GI tract. [Grade B]
Surgery	US ASPEN (2017)	Consensus recommendation. When is parenteral nutrition appropriate?³	• Consider pre-operative PN in severely malnourished patients unable to tolerate sufficient oral intake or EN. • Reserve post-operative PN for severely malnourished patients unable to tolerate EN for more than 7 days, unless initiated pre-operatively.
Bariatric Surgery	US American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic & Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologist (2019)	Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures–2019 update⁴³	EN or PN should be considered in bariatric surgery patients at high nutritional risk (e.g., NRS ≥ 3); PN should be considered in patients who are unable to meet their needs using their GI tract for at least 5–7 days with non-critical illness or 3–7 days with critical illness. [Grade D] PN should be considered in patients with severe protein malnutrition and/or hypoalbuminemia, not responsive to oral or EN protein supplementation. [Grade D] Severe malnutrition should prompt hospital admission for initiation of nutritional support. [Grade D] The initiation and formulation of EN or PN should be guided by current clinical practice guidelines. [Grade D]
Pressure Ulcers	Europe, US, Australia, New Zealand, Hong Kong, Singapore National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel and Pan Pacific Pressure Injury Alliance (2025)	Prevention and Treatment of Pressure Ulcers/Injuries: Clinical Practice Guideline: Nutrition in pressure injury prevention⁴⁴	We suggest that nutritional supplementation be implemented for individuals at risk of pressure injuries who have been identified as malnourished or at risk of malnutrition when nutritional needs are not met by usual dietary intake. [Conditional recommendation, very low certainty of evidence] Consider options in the following priority when providing nutrition supplementation: increased and optimised oral intake, fortified foods, oral supplements, enteral tube feeding, parenteral supplementation.
HIV and Chronic Infectious Diseases	Europe ESPEN (2006)	ESPEN guidelines on enteral nutrition: wasting in HIV and other chronic infectious diseases⁴⁵	If oral intake is possible, nutritional intervention should be implemented according to the following scheme [Grade C]: nutritional counselling; oral nutritional supplements; tube feeding; PN.
Dementia	Europe ESPEN (2015)	Guidelines on nutrition in dementia (2015)⁴⁶	We suggest parenteral fluids for a limited duration in periods of insufficient fluid intake to overcome a crisis situation. [Grade of evidence: very low] We recommend against the use of artificial nutrition (EN, PN, and parenteral fluids) in the terminal phase of life. [Grade of evidence: very low]
Dementia	Europe ESPEN (2024)	ESPEN guideline on nutrition and hydration in dementia – Update 2024⁴⁷	Enteral and parenteral nutrition and parenteral fluids shall NOT be initiated in persons with dementia in the terminal phase of life. [Grade GPP – strong consensus 96% agreement] Parenteral nutrition can be used temporarily in patients with mild or moderate dementia, if significantly low nutritional intake is predominantly caused by a potentially reversible condition, but enteral nutrition is contraindicated or not tolerated. [Grade GPP – strong consensus 100% agreement] Parenteral fluids can be given temporarily in periods of insufficient fluid intake to overcome a crisis situation. [Grade GPP – strong consensus 100% agreement]
Polymorbid Patients	Europe ESPEN (2024)	ESPEN practical guideline: Nutritional support for polymorbid medical inpatients⁴⁸	In polymorbid medical inpatients whose nutritional requirements cannot be met orally, EN before parenteral nutrition (PN) can be administered to ensure reaching nutritional goals. [Grade 0; Strong consensus 100%] In polymorbid medical inpatients whose nutritional requirements cannot be met orally, the use of EN may be superior to PN because of a lower risk of infectious, non-infectious complications and maintenance of gut integrity. [Grade 0, Strong consensus 100%]

ACG, American College of Gastroenterology; ARF, acute renal failure; ASPEN, American Society of Parenteral and Enteral nutrition; BM, biomedical endpoints; CAPD, continuous ambulatory peritoneal dialysis; CD, Crohn’s disease; CKD, chronic kidney disease; CRF, chronic renal failure; ECFS, European Cystic Fibrosis Society; EN, enteral nutrition; ESPEN, European Society for Clinical Nutrition and Metabolism; ESPGHAN, European Society for Paediatric Gastroenterology, Hepatology and Nutrition; GPP, good practice point; HD, haemodialysis; HPN, home parenteral nutrition; IBW, ideal body weight; ICU, intensive care unit; IDPN, Intradialytic parenteral nutrition; IF, intestinal failure; IPAA, or intraperitoneal amino acids; IV, intravenous; NICE, National Institute for Health and Care Excellence; NRS, nutrition risk score; NUTRIC, Nutrition Risk in the Critically Ill; ONS, oral nutritional supplementation; PEW, protein-energy wasting; PN, parenteral nutrition; SPN, supplemental parenteral nutrition; TPN, total parenteral nutrition; UC, ulcerative colitis

CANCER

Table 4.35

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Oncology (parts of guidelines relevant to PN presented here, standard formulas only)

Patient Group	Country & Body	Title	Recommendation, Guidance, or Standard [Grade of Evidence]
Patients with Cancer	Europe ESPEN (2021)	ESPEN practical guideline: Clinical Nutrition in cancer⁴⁹	Modes of nutrition; when to escalate: If a decision has been made to feed a patient, we recommend EN if oral nutrition remains inadequate despite nutritional interventions (counselling, ONS), and PN if EN is not sufficient or feasible. [Strength of recommendation: strong; level of evidence: moderate] Refeeding syndrome: If oral food intake has been decreased severely for a prolonged period of time, we recommend to increase nutrition (oral, EN, or PN) slowly over several days and to take additional precautions to prevent refeeding syndrome. [Strong; low] Home artificial nutrition: In patients with chronic insufficient dietary intake and/or uncontrollable malabsorption, we recommend home artificial nutrition (PN or EN) in suitable patients. [Strong; low] Radiotherapy: We do not recommend PN as a general treatment in radiotherapy but only if adequate oral nutrition/EN is not possible (e.g., in severe radiation enteritis or severe malabsorption). [Strong; moderate] Medical oncology; curative or palliative anticancer drug treatment: In a patient undergoing curative anticancer drug treatment, if oral food intake is inadequate despite counselling and ONS, we recommend supplemental EN or, if this is not sufficient or possible, PN. [Strong; very low] High-dose chemotherapy and HSCT: During intensive chemotherapy and after HSCT, we recommend to maintain physical activity and to ensure adequate nutritional intake, which may require EN or PN. [Strong; very low] If oral nutrition is inadequate, EN is preferred over PN unless there is severe mucositis, intractable vomiting, ileus, severe malabsorption, protracted diarrhoea, or symptomatic GI graft versus host disease. [Weak; low] Patients with advanced cancer receiving no anticancer treatment: We recommend offering and implementing nutritional interventions in patients with advanced cancer only after considering together with the patient the prognosis and both the expected benefit on quality of life and potentially survival, as well as the burden associated with nutritional care. [Strong; low]
Patients with Cancer	US Academy of Nutrition and Dietetics (2013)	Oncology (ONC) guideline (2013)⁵⁰	In adult oncology patients who have pre-cachexia or cancer cachexia, prompt and aggressive intervention to address nutrition impact symptoms and preserve or prevent loss of lean body mass and weight should be initiated by the registered dietitian nutritionist. Early rather than later intervention to prevent weight loss is more likely to be effective. The metabolic derangements in cancer cachexia that promote wasting can lead to loss of weight and lean body mass and poor outcomes. Medical nutrition therapy (MNT) in adult patients undergoing chemotherapy or radiation treatment: Adult oncology patients undergoing chemotherapy or radiation treatment should receive MNT, which has been shown to improve treatment outcomes in patients undergoing chemotherapy, radiation, or chemoradiotherapy in ambulatory or outpatient and inpatient oncology settings.
Patients with Cancer	US ASPEN (2009)	Nutrition support therapy during adult anticancer treatment and in hematopoietic cell transplantation (2009)⁵¹	Adult cancer patients undergoing anti-cancer treatment and HSCT: Nutrition support therapy is appropriate in patients undergoing HSCT who are malnourished and who are anticipated to be unable to ingest and/or absorb adequate nutrients for a prolonged period. When PN is used, it should be discontinued as soon as toxicities have resolved after stem cell engraftment. [Grade B]
Non-Surgical Cancer Patients	Europe ESPEN (2009)	ESPEN guidelines on parenteral nutrition: non-surgical oncology⁵²	Nutritional support should be started if a patient is undernourished, if it is anticipated that they will be unable to eat for more than 7 days, or if inadequate food intake (< 60% of estimated energy expenditure) is anticipated for more than 10 days. [Grade C]. If nutritional support cannot be given through the enteral route, it has to be delivered by vein. SPN should substitute the difference between the actual oral/enteral intake and estimated requirements. [Grade C] Perioperative PN: Recommended in malnourished candidates for artificial nutrition, when EN is not possible. [Grade A] Anti-cancer therapy: The routine use of PN during chemotherapy, radiotherapy, or combined therapy is not recommended. [Grade A] However, if patients are malnourished or facing longer than 1 week of starvation, and EN support is not feasible, PN is recommended. [Grade C] If patients develop GI toxicity from chemotherapy or radiation therapy, short-term PN is usually better tolerated (and more efficient) than EN to restore intestinal function and prevent nutritional deterioration. Intestinal failure: In aphagic patients with incurable cancer, survival may be limited more by under-nutrition than by tumour progression. Long-term PN should be offered to patients with intestinal failure if: (1) enteral nutrition is insufficient; (2) expected survival due to tumour progression is longer than 2–3 months; (3) PN is expected to stabilise or improve performance status and quality of life; (4) the patient desires this mode of nutritional support. [Grade C] Weight-losing cancer patients: SPN is of probable benefit in supporting patients with incurable cancer with weight loss and reduced nutrient intake. [Grade B] HSCT: PN should be reserved for those with severe mucositis, ileus, or intractable vomiting. [Grade B] No clear recommendation can be made timing of PN initiation. Withdrawal should be considered when patients are able to tolerate approximately 50% of their requirements enterally. [Grade C]
Patients with Cancer-Related Cachexia	Europe European Society For Medical Oncology (ESMO) (2022)	Cancer cachexia in adult patients: ESMO Clinical Practice Guidelines⁵³	Regular nutritional screening and nutritional support, including (if necessary) enteral nutrition or PN, is recommended in all patients receiving anticancer treatment and in those with an expected survival of more than a few months. [V, B] If safe, the oral route should be the first option for nutritional support. Enteral tube feeding may be used in cases of dysphagia if the small bowel function is preserved. PN should be considered if oral intake and tube feeding are not tolerated or remain inadequate. [II, A] Home PN should be offered to patients if their QoL and/or length of survival is expected to be severely compromised by progressive malnutrition. Indicators of a potential benefit are ECOG/WHO PS 0-2, a low level of systemic inflammation (normal levels of serum albumin, modified Glasgow Prognostic Score <2), and the absence of metastatic disease. [V, B] There is insufficient evidence to routinely recommend supplemental PN in hypophagic, malnourished patients receiving chemotherapy to improve QoL and nutrition parameters. [V, B]
Patients with Cancer of the Aerodigestive Tract	Europe European Society For Medical Oncology (ESMO) (2022)	Oesophageal cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up⁵⁴	Supportive care for patients with advanced oesophageal cancer should follow the recommendations provided in the ESMO Clinical Practice Guideline for gastric cancer, including early palliative care referral and nutritional support. Local and locoregional diseases: Correction of malnutrition is often warranted before curative-intent therapy can be started.
Patients Receiving Palliative Care	US ASPEN (2017)	Consensus recommendation. When is parenteral nutrition appropriate?³	Do not use PN solely to treat poor oral intake and/or cachexia associated with advanced malignancy. Limit the use of PN in palliative care to carefully selected candidates, with an expected survival of 2-3 months, for whom oral intake or EN is not feasible. Evaluate clinical factors and performance status when selecting candidates for PN at the end of life. Involve patients and caregivers in a clear and complete dialogue regarding realistic goals of PN as well as the potential risks and burdens.

ASPEN, American Society of Parenteral and Enteral nutrition; EN, enteral nutrition; ESPEN, European Society for Clinical Nutrition and Metabolism; GI, gastrointestinal; HSCT, hematopoietic stem cell transplant; MNT, medical nutrition therapy; ONS, oral nutritional supplementation; SPN, supplemental parenteral nutrition

Table 4.36

Grading of recommendations in NICE guidelines (adapted from NICE 2006)²

Grade	Evidence
A	• At least one meta-analysis, systematic review, or RCT rated as 1++ (i.e., high-quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias), and directly applicable to the target population, or • A systematic review of RCTs or a body of evidence consisting principally of studies rated as 1+ (i.e., well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias), directly applicable to the target population, and demonstrating overall consistency of results • Evidence drawn from a NICE technology appraisal
B	• A body of evidence including studies rated as 2++ (i.e., high-quality systematic reviews of case–control or cohort studies, high-quality case–control or cohort studies with a very low risk of confounding, bias, or chance and a high probability that the relationship is causal) directly applicable to the target population, and demonstrating overall consistency of results, or • Extrapolated evidence from studies rated as 1++ or 1+
C	• A body of evidence including studies rated as 2+ (i.e., well-conducted case–control or cohort studies with a low risk of confounding, bias, or chance and a moderate probability that the relationship is causal), directly applicable to the target population and demonstrating overall consistency of results, or • Extrapolated evidence from studies rated as 2++
D	• Evidence level 3 (i.e., non-analytic studies, e.g., case reports, case series) or 4 (i.e., expert opinion), or • Extrapolated evidence from studies rated as 2+, or • Formal consensus
D (GPP)	• A good practice point (GPP) is a recommendation for best practice based on the experience of the Guideline Development Group

NICE, National Institute of Health and Care Excellence; RCT, randomised controlled trial

Table 4.37

Grading levels of evidence used in ESPEN guidelines before 2015 (adapted from Schutz 2006)⁵⁵

Grade	Level of evidence	Requirement
A	Ia Ib	• Meta-analysis of randomised controlled trials (RCTs) • At least one RCT
B	IIa IIb III	• At least one well-designed controlled trial without randomisation • At least one other type of well-designed quasi-experimental study • Well-designed non-experimental descriptive studies such as comparative studies, correlation studies, case-control studies
C	IV	• Expert opinions and/or clinical experience of respected authorities

RCT, randomised controlled trial

Table 4.38

Levels of evidence and grades of recommendation used in ESPEN guidelines from 2015 (adapted from Bischoff et al., 2015)⁵⁶

Level of evidence
1++	High-quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias
1+	Well-conducted meta-analyses, systematic reviews, or RCTs with a low risk of bias
1−	Meta-analyses, systematic reviews, or RCTs with a high risk of bias
2++	High-quality systematic reviews of case–control or cohort studies High-quality case–control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal
2+	Well-conducted case–control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal
2-	Case–control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is causal
3	Non-analytic studies (e.g., case reports, case series)
4	Expert opinion
Grades of recommendation
A	At least one meta-analysis, systematic review, or RCT rated as 1++, and directly applicable to the target population; or A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results
B	A body of evidence including studies rated as 2++, directly applicable to the target population; or A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or extrapolated evidence from studies rated as 1++ or 1+
O	Evidence level 3 or 4; or extrapolated evidence from studies rated as 2++ or 2+
GPP	Good practice points/expert consensus: Recommended best practice based on the clinical experience of the guideline development group

RCT, randomised controlled trial

Table 4.39

ESPGHAN and ESPEN grades of evidence and strength of recommendation¹²

Grades of evidence	Definition of evidence⁵⁷
High	Further research is very unlikely to change our confidence in the estimate of effect
Moderate	Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Low	Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Very low	Any estimate of effect is very uncertain
Strength of recommendation
Strong	We recommend/do not recommend
Weak	We suggest/do not suggest

Table 4.40

ASPEN grading of guidelines and levels of evidence (for guidelines published before 2012)⁴⁵

Grading of guidelines
A	Supported by at least two level I investigations
B	Supported by one level I investigation
C	Supported by at least one level II investigation
D	Supported by at least one level III investigation
E	Supported by level IV or V evidence
Levels of evidence
I	Large randomised trials with clear-cut results; low risk of false-positive (alpha) and/ or false-negative (beta) error
II	Small randomised trials with uncertain results; moderate-to-high risk of false-positive (alpha) and/or false-negative (beta) error
III	Non-randomised cohort with contemporaneous controls
IV	Non-randomised cohort with historical controls
V	Case series, uncontrolled studies, and expert opinion

Since 2012, ASPEN has adopted a revised method of evidence grading based on the GRADE methodology (Druyan 2012⁵⁹) (see Table 4.41)

Table 4.41

ASPEN grading of guidelines and levels of evidence (for guidelines published after 2012)⁵⁹

Quality of evidence and definitions
High	Further research is very unlikely to change our confidence in the estimate of effect
Moderate	Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Low	Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Very low	Any estimate of effect is very uncertain
Quality of evidence	Weighing risks vs benefits	GRADE recommendation	Clinical guideline statement
High to very low	Net benefits outweigh harms	Strong	We recommend
High to very low	Trade-offs for patient are important	Weak	We suggest
High to very low	Uncertain trade-offs	Further research needed	We cannot make a recommendation at this time

Based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology (Druyan 2012)⁵⁹

Table 4.42

Society of Critical Care Medicine (SCCM) and ASPEN determination of the quality of evidence¹²

Quality of evidence	Weighing risks vs benefits	GRADE recommendation	Clinical guideline statement
High to very low	Net benefits outweigh harms	Strong	We recommend
High to very low	Trade-offs for patient are important	Weak	We suggest
High to very low	Uncertain trade-offs	Further research needed	We cannot make a recommendation at this time

GRADE, Grading of Recommendations, Assessment, Development, and Evaluation

Table 4.43

Surviving Sepsis Campaign Guidelines Committee including the Pediatric Subgroup: determination of the quality of evidence

Underlying methodology
A	(high) RCTs
B	(moderate) Downgraded RCTs or upgraded observational studies
C	(low) Well-done observational studies with control RCTs
D	(very low) Downgraded controlled studies or expert opinion based on other evidence
Factors that may decrease the strength of evidence
1	Poor quality of planning and implementation of available RCTs, suggesting high likelihood of bias
2	Inconsistency of results, including problems with subgroup analyses
3	Indirectness of evidence (differing population, intervention, control, outcomes, comparison)
4	Imprecision of results
5	High likelihood of reporting bias
Main factors that may increase the strength of evidence
1	Large magnitude of effect (direct evidence, relative risk > 2 with no plausible confounders)
2	Very large magnitude of effect with relative risk > 5 and no threats to validity (by two levels)
3	Dose-response gradient

RCT, randomised controlled trial

Table 4.44

American College of Gastroenterology: quality of evidence and strength of recommendation

Quality of evidence	Strength of recommendation
High	Further research is very unlikely to change our confidence in the estimate of effect
Moderate	Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Low	Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Very low	Any estimate of the effect is very uncertain

Based on Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology (Druyan 2012)⁵⁹

Table 4.45

Academy of Nutrition and Dietetics recommendation ratings

Statement Rating	Definition	Implication for Practice
Strong	A Strong recommendation means that the workgroup believes that the benefits of the recommended approach clearly exceed the harms (or that the harms clearly exceed the benefits in the case of a strong negative recommendation), and that the quality of the supporting evidence is excellent/good (grade I or II).* In some clearly identified circumstances, strong recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits strongly outweigh the harms.	Practitioners should follow a Strong recommendation unless a clear and compelling rationale for an alternative approach is present.
Fair	A Fair recommendation means that the work group believes that the benefits exceed the harms (or that the harms clearly exceed the benefits in the case of a negative recommendation), but the quality of evidence is not as strong (grade II or III).* In some clearly identified circumstances, recommendations may be made based on lesser evidence when high-quality evidence is impossible to obtain and the anticipated benefits outweigh the harms.	Practitioners should generally follow a Fair recommendation but remain alert to new information and be sensitive to patient preferences.
Weak	A Weak recommendation means that the quality of evidence that exists is suspect or that well-done studies (grade I, II, or III)* show little clear advantage to one approach versus another.	Practitioners should be cautious in deciding whether to follow a recommendation classified as Weak, and should exercise judgment and be alert to emerging publications that report evidence. Patient preference should have a substantial influencing role.
Consensus	A Consensus recommendation means that Expert opinion (grade IV) supports the guideline recommendation even though the available scientific evidence did not present consistent results, or controlled trials were lacking.	Practitioners should be flexible in deciding whether to follow a recommendation classified as Consensus, although they may set boundaries on alternatives. Patient preference should have a substantial influencing role.
Insufficient Evidence	An Insufficient Evidence recommendation means that there is both a lack of pertinent evidence (grade V)* and/or an unclear balance between benefits and harms.	Practitioners should feel little constraint in deciding whether to follow a recommendation labelled as Insufficient Evidence and should exercise judgment and be alert to emerging publications that report evidence that clarifies the balance of benefit versus harm. Patient preference should have a substantial influencing role.
Recommendations are categorised in terms of either imperative or conditional statements. Imperative statements are broadly applicable to the target population and do not impose restraints on their pertinence. Imperative recommendations may include terms such as “should” or “may” and do not contain conditional text that would limit their applicability to specified circumstances. Conditional statements clearly define a specific situation or population. Conditional recommendations are often presented in an if/then format, such that if CONDITION then ACTION(S) because REASONS(S) Fulfilment of the condition triggers one or more guideline-specified actions.

Academy Evidence-Based Nutrition Practice Guidelines published on the Evidence Analysis Library (EAL) are assigned a rating of: strong, fair, weak, consensus, or insufficient evidence based on the following criteria. Criteria for Recommendation Ratings Adapted by the Academy of Nutrition and Dietetics from the American Academy of Pediatrics, Classifying Recommendations for Clinical Practice Guidelines, Pediatrics.2004;114;874-877s

Table 4.46

Signposts for evidence grading by other international organisations

Recommending body	Signpost for evidence grading
National Pressure Ulcer Advisory Panel (NPUAP), European Pressure Ulcer Advisory Panel (EPUAP) and Pan-Pacific Pressure Injury Alliance (PPPIA)	https://journals.lww.com/aswcjournal/fulltext/2024/03000/protocol_for_the_development_of_the_fourth_edition.5.aspx
Academy of Nutrition and Dietetics	https://www.andeal.org/recommendation-ratings
American Society for Enteral and Parenteral Nutrition (ASPEN)	https://aspenjournals.onlinelibrary.wiley.com/doi/full/10.1177/0148607111420157
North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN)	https://www.naspghan.org/content/63/en/professional-educa- tion/publications/clinical-guidelines
Surviving Sepsis Campaign	https://www.esicm.org/wp-content/uploads/2018/03/SSC-guidelines-2012.pdf https://www.sccm.org/clinical-resources/guidelines/guidelines/surviving-sepsis-campaign-international-guidelines
European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN)	www.clinicalnutritionjournal.com/action/showPdf?pii=S0261-5614%2823%2900457-0
European Society for Clinical Nutrition and Metabolism (ESPEN)	http://www.espen.org/files/ESPEN-Guidelines/0 Standard_ operating_procedures_for_ESPEN_guidelines_and_consen- sus_papers_2.pdf
The European Society for Medical Oncology (ESMO)	https://pmc.ncbi.nlm.nih.gov/articles/PMC11055998/

Table 4.47

Definitions of parenteral nutrition according to recommending organisation

Organisation	Term	Definition
Academy of Nutrition and Dietetics⁶⁰	Medical nutrition therapy (MNT)	Evidence‐based application of the nutrition care process. The provision of MNT (to a patient/client) may include one or more of the following: nutrition assessment/reassessment, nutrition diagnosis, nutrition intervention, nutrition monitoring, evaluation that typically results in the prevention, delay, or management of diseases and/or conditions.
Academy of Nutrition and Dietetics⁶⁰	Parenteral nutrition (PN)	IV administration of nutrients such as amino acids, carbohydrate, lipid, and added vitamins and minerals delivered via central (into a large-diameter vein, usually the superior vena cava adjacent to the right atrium) or peripheral route (into a peripheral vein, usually of the hand or forearm).
ASPEN⁶¹	MNT	Assessment of the nutrition status of a patient, followed by nutrition therapy, ranging from diet modification to the administration of EN or PN.
ASPEN⁶¹	PN	The administration of IV nutrients.
ESPEN⁶²	MNT	Encompasses oral nutritional supplements, enteral tube feeding (EN), and PN. The latter two have traditionally been called artificial nutrition, but this term is suggested to be replaced by MNT.
	PN	Nutrition therapy provided through IV administration of nutrients such as amino acids, glucose, lipids, electrolytes, vitamins, and trace elements; can be central through a central venous line or peripheral through a peripheral IV line.
	Total PN (TPN) (also, exclusive PN)	The patient's complete nutritional needs (all macro and micronutrients) are covered by PN, and nutrition is not given by any route other than IV.
	Supplemental PN (SPN) (also, partial PN or complementary PN)	Nutrition is provided in addition to PN by any route other than IV; for example, when the oral or enteral tube routes cannot independently achieve the defined nutritional care plan target.
	Home PN (HPN)	PN used outside the hospital. Home TPN or SPN is often used for patients with chronic intestinal failure, malignant obstruction, or partial obstruction of the gastrointestinal tract.
	Intra-dialytic PN (IDPN)	PN given IV through the venous line of the dialysis circuit, and thus given cyclically during the dialysis session. IDPN is not a routine technique for supplemental nutrition therapy, but may be indicated to prevent nutritional deterioration in patients receiving dialysis treatment when other methods of nutrition therapy have proved insufficient to meet nutritional and metabolic needs.

ASPEN, American Society of Parenteral and Enteral nutrition; ESPEN, European Society for Clinical Nutrition and Metabolism; IV, intravenous

Next section →4.3.2 Guidelines: From theory to practice for enhanced patient care

4.3 Recommendations from international and internationally recognised guidelines: PN

4.3.1 Key Parenteral nutrition (PN) Guidelines: Summary Tables

GENERAL

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – General (parts of guidelines relevant to PN, standard formulas only)

OLDER PEOPLE

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Older People (parts of guidelines relevant to PN, standard formulas only)

CHILDREN

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Children (parts of guidelines relevant to PN, standard formulas only)

SPECIFIC DISEASES

CANCER

Summary of some examples of evidence-based international and internationally recognised guidelines referring to parenteral nutrition (PN) as an integral part of patient and disease management – Oncology (parts of guidelines relevant to PN presented here, standard formulas only)

Grading of recommendations in NICE guidelines (adapted from NICE 2006)2

Grading levels of evidence used in ESPEN guidelines before 2015 (adapted from Schutz 2006)55

Levels of evidence and grades of recommendation used in ESPEN guidelines from 2015 (adapted from Bischoff et al., 2015)56

ESPGHAN and ESPEN grades of evidence and strength of recommendation12

ASPEN grading of guidelines and levels of evidence (for guidelines published before 2012)45

ASPEN grading of guidelines and levels of evidence (for guidelines published after 2012)59

Society of Critical Care Medicine (SCCM) and ASPEN determination of the quality of evidence12

Surviving Sepsis Campaign Guidelines Committee including the Pediatric Subgroup: determination of the quality of evidence

American College of Gastroenterology: quality of evidence and strength of recommendation

Academy of Nutrition and Dietetics recommendation ratings

Signposts for evidence grading by other international organisations

Definitions of parenteral nutrition according to recommending organisation

Grading of recommendations in NICE guidelines (adapted from NICE 2006)²

Grading levels of evidence used in ESPEN guidelines before 2015 (adapted from Schutz 2006)⁵⁵

Levels of evidence and grades of recommendation used in ESPEN guidelines from 2015 (adapted from Bischoff et al., 2015)⁵⁶

ESPGHAN and ESPEN grades of evidence and strength of recommendation¹²

ASPEN grading of guidelines and levels of evidence (for guidelines published before 2012)⁴⁵

ASPEN grading of guidelines and levels of evidence (for guidelines published after 2012)⁵⁹

Society of Critical Care Medicine (SCCM) and ASPEN determination of the quality of evidence¹²