Vitamin C in Home Parenteral Nutrition: A Need for Monitoring

A scoping review of parenteral requirements (macronutrients, fluid, electrolytes and micronutrients) in adults with chronic intestinal failure receiving home parenteral nutrition

INTRODUCTION

Home parenteral nutrition (HPN) prescriptions should be individualised in adults with chronic intestinal failure (IF). The aims of the review were to explore HPN requirements and available guidelines and to determine whether adults (≥ 18 years) receive recommended parenteral nutrient doses.

METHODS

Online databases searches identified empirical evidence (excluding case-reports), reviews and guidelines (Published 2006-2024 in English language). Additional reference lists were hand-searched. Older studies, cited in national guidelines were highlighted to map evidence source. Two reviewers screened 1660 articles independently, with 98 full articles assessed and 78 articles included (of which 35 were clinical studies). Citation tracking identified 12 older studies.

RESULTS

A lack of evidence was found assessing parenteral macronutrient (amounts and ratios to meet energy needs), fluid and electrolyte requirements. For micronutrients, 20 case series reported serum levels as biomarkers of adequacy (36 individual micronutrient levels reported). Studies reported levels below (27 out of 33) and above (24 out of 26) reference ranges for single micronutrients, with associated factors explored in 11 studies. Guidelines stated recommended parenteral dosages. Twenty-four studies reported variable proportions of participants receiving HPN dosages outside of guideline recommendations. When associated factors were assessed, two studies showed nutrient variation with type of HPN administered (multichamber or individually compounded bags). Five studies considered pathophysiological IF classification, with patients with short bowel more likely to require individualised HPN and more fluid and sodium.

CONCLUSIONS

This review highlights substantial evidence gaps in our understanding of the parenteral nutritional requirements of adult receiving HPN. The conclusions drawn were limited by temporal bias, small samples sizes, and poor reporting of confounders and dose. Optimal HPN nutrient dose still need to be determined to aid clinical decision-making and further research should explore characteristics influencing HPN prescribing to refine dosing recommendations.

ESPEN guideline on chronic intestinal failure in adults - Update 2023

BACKGROUND & AIMS

In 2016, ESPEN published the guideline for Chronic Intestinal Failure (CIF) in adults. An updated version of ESPEN guidelines on CIF due to benign disease in adults was devised in order to incorporate new evidence since the publication of the previous ESPEN guidelines.

METHODS

The grading system of the Scottish Intercollegiate Guidelines Network (SIGN) was used to grade the literature. Recommendations were graded according to the levels of evidence available as A (strong), B (conditional), 0 (weak) and Good practice points (GPP). The recommendations of the 2016 guideline (graded using the GRADE system) which were still valid, because no studies supporting an update were retrieved, were reworded and re-graded accordingly.

RESULTS

The recommendations of the 2016 guideline were reviewed, particularly focusing on definitions, and new chapters were included to devise recommendations on IF centers, chronic enterocutaneous fistulas, costs of IF, caring for CIF patients during pregnancy, transition of patients from pediatric to adult centers. The new guideline consist of 149 recommendations and 16 statements which were voted for consensus by ESPEN members, online in July 2022 and at conference during the annual Congress in September 2022. The Grade of recommendation is GPP for 96 (64.4%) of the recommendations, 0 for 29 (19.5%), B for 19 (12.7%), and A for only five (3.4%). The grade of consensus is "strong consensus" for 148 (99.3%) and "consensus" for one (0.7%) recommendation. The grade of consensus for the statements is "strong consensus" for 14 (87.5%) and "consensus" for two (12.5%).

CONCLUSIONS

It is confirmed that CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for the underlying gastrointestinal disease and to provide HPN support. Most of the recommendations were graded as GPP, but almost all received a strong consensus.

25 year experience of patterns of plasma vitamin C levels in patients requiring home parenteral support

OBJECTIVE

Vitamin C deficiency is common in patients with chronic intestinal failure. Risk factors are poorly understood and guidelines for monitoring largely based on expert opinion. The aim of this study was to describe patterns of vitamin C deficiency in patients on long-term home parenteral support (HPS).

DESIGN

A retrospective review of a prospectively collated database for 236 HPS patients cared for in Glasgow, from 1998 to 2023, was interrogated for subjects with paired CRP and vitamin C measurements. Following analysis of the impact of CRP on vitamin C levels, further review of associated clinical, micronutrient and dietetic details in those with a paired CRP <5 mg L-1 were used to identify risk factors for hypoascorbataemia.

RESULTS

1527 recorded episodes with paired CRP and vitamin C measurements were analysed. Period prevalence of hypoascorbataemia was between 29.3 and 52.5%, depending on choice of the lower reference range for vitamin C as either 15 μmol L-1 or 26.1 μmol L-1. The influence of CRP appeared most significant early during HPS with other factors, including extensive mucosal disease, precedent surgery or presence of a colostomy identified as more significant on multivariate analysis for those on long-term HPS (OR 1.3261-1.5609, 1.0752-1.1008, and 0.6260-0.6663 for threshold vitamin C of 26.1 or 15 μmol L-1 respectively).

CONCLUSION

Vitamin C may present differently in long term HPS patients in comparison to those in the acute phase of illness. An evidence based approach to guideline development should be promoted to reduce morbidity.

An evaluation of plasma vitamin C concentrations in individuals requiring home parenteral nutrition

BACKGROUND

Ascorbic acid (VitC) is an essential coenzyme to maintain health, but there are minimal data on the adequacy of VitC supply in patients requiring home parenteral nutrition (HPN).

METHODS

A prospective pilot study measuring plasma VitC, serum vitamins A,D,E and the minerals zinc, copper, selenium and magnesium in 28 adult HPN-dependent (≥6 months) patients was carried out.

RESULTS

57% of patients had insufficient VitC status. There was a strong, positive correlation between HPN provision of VitC and plasma VitC concentrations (r_s =0.663, p=0.00) with 83% insufficiency rate below a provision of 800mg/week. There was no association seen between plasma VitC and number of HPN days/week (p=0.539); number of months on HPN (p=0.773) or dependency on HPN (86±31% of energy requirements met via HPN v 77±23%, p=0.39).

CONCLUSIONS

VitC insufficiency is prevalent in HPN-dependent patients. Our data highlight the need for regular monitoring of VitC in those living with type III intestinal failure. This article is protected by copyright. All rights reserved.