Accuracy of home enteral feed preparation for children with inherited metabolic disorders

Enteral tube feeding in patients receiving dietary treatment for metabolic diseases: A retrospective analysis in a large French cohort

Context

A strictly controlled diet (often involving enteral tube feeding (ETF)) is part of the treatment of many inherited metabolic diseases (IMDs).

Objective

To describe the use of ETF in a large cohort of patients with IMDs.

Design

A retrospective analysis of ETF in patients with urea cycle disorders (UCDs), organic aciduria (OA), maple syrup disease (MSUD), glycogen storage diseases (GSDs) or fatty acid oxidation disorders (FAODs) diagnosed before the age of 12 months.

Setting

The reference center for IMDs at Necker Hospital (Paris, France).

Results

190 patients born between January 1991 and August 2017 were being treated for OA (n = 60), UCDs (n = 55), MSUD (n = 32), GSDs (n = 26) or FAODs (n = 17). Ninety-eight of these patients (52%) received ETF (OA subgroup: n = 40 (67%); UCDs: n = 12 (22%); MSUD: n = 9 (28%); GSDs: n = 23 (88%); FAODs: n = 14 (82%)). Indications for ETF were feeding difficulties in 64 (65%) patients, cessation of fasting in 39 (40%), and recurrent metabolic decompensation in 14 (14%). Complications of ETF were recorded in 48% of cases, more frequently with nasogastric tube (NGT) than with gastrostomy. Among patients in whom ETF was withdrawn, the mean duration of ETF was 5.9 (SD: 4.8) years (range: 0.6–19.8 years). The duration of ETF was found to vary from one disease subgroup to another (p = 0.051). While the longest median duration was found in the GSD subgroup (6.8 years), the shortest one was found in the UCD subgroup (0.9 years).

Conclusion

ETF is an integral part of the dietary management of IMDs. The long duration of ETF and the specific risks of NGT highlights the potential value of gastrostomy.

In this study at a French tertiary hospital, we documented the indications, modalities, duration and complications of enteral tube feeding in a cohort of patients with inherited metabolic diseases.

The challenge of nutritional profiling of a protein-free feed module for children on low protein tube feeds with organic acidaemias

BACKGROUND

Enteral tube feeding for children with organic acidaemias (OA) is recommended. Protein restriction, providing minimum safe levels of protein intake, is advocated. Standard paediatric tube feeding formulae provide more than the minimum safe protein requirements and are unsuitable in OA without modification. Modified paediatric enteral feeds consist of several modular ingredients. The aim of this prospective longitudinal interventional study was to assess the efficacy of a premeasured novel protein-free module developed for children aged over 12 months compared to conventional practice.

METHODS

In total, 15 children with OA (11.6-31 kg) needing enteral feeding were recruited. The protein-free module, from either a protein-free infant feed or modular ingredients, was replaced by the study feed. To ensure metabolic stability, energy and protein intake were unchanged. Dietary intake, anthropometry and nutritional biochemistry were recorded at baseline and week 26.

RESULTS

Dietary intakes of magnesium (P = 0.02), sodium (P = 0.005), vitamin D (P = 0.04), docosahexaenoic acid (P = 0.01) and arachidonic acid (P = 0.001) significantly improved; plasma selenium (P = 0.002) and whole blood glutathione peroxidase (P = 0.02) significantly increased. Feed preparation accuracy as measured by composition analysis showed consistent errors both in pre- and study feeds.

CONCLUSIONS

A protein-free module improved nutritional intake and biochemistry, although feed preparation errors remained a common finding.

Proposed guidelines for the diagnosis and management of methylmalonic and propionic acidemia

Methylmalonic and propionic acidemia (MMA/PA) are inborn errors of metabolism characterized by accumulation of propionic acid and/or methylmalonic acid due to deficiency of methylmalonyl-CoA mutase (MUT) or propionyl-CoA carboxylase (PCC). MMA has an estimated incidence of ~ 1: 50,000 and PA of ~ 1:100’000 -150,000. Patients present either shortly after birth with acute deterioration, metabolic acidosis and hyperammonemia or later at any age with a more heterogeneous clinical picture, leading to early death or to severe neurological handicap in many survivors. Mental outcome tends to be worse in PA and late complications include chronic kidney disease almost exclusively in MMA and cardiomyopathy mainly in PA. Except for vitamin B₁₂ responsive forms of MMA the outcome remains poor despite the existence of apparently effective therapy with a low protein diet and carnitine. This may be related to under recognition and delayed diagnosis due to nonspecific clinical presentation and insufficient awareness of health care professionals because of disease rarity.

These guidelines aim to provide a trans-European consensus to guide practitioners, set standards of care and to help to raise awareness. To achieve these goals, the guidelines were developed using the SIGN methodology by having professionals on MMA/PA across twelve European countries and the U.S. gather all the existing evidence, score it according to the SIGN evidence level system and make a series of conclusive statements supported by an associated level of evidence. Although the degree of evidence rarely exceeds level C (evidence from non-analytical studies like case reports and series), the guideline should provide a firm and critical basis to guide practice on both acute and chronic presentations, and to address diagnosis, management, monitoring, outcomes, and psychosocial and ethical issues. Furthermore, these guidelines highlight gaps in knowledge that must be filled by future research. We consider that these guidelines will help to harmonize practice, set common standards and spread good practices, with a positive impact on the outcomes of MMA/PA patients.

Accuracy of formula preparation equipment for liquid measurement

Background

Modular specialist feeds may consist of a number of individual liquid ingredients. Accurate feed preparation is dependent on competent liquid measurement. We investigate the accuracy of two measuring jugs (one retail mix-and-measure; and one produced to laboratory standards); and the influence of volume and technique on accuracy.

Materials and methods

20 health professionals aged 18–60 y (mean: 46 y) measured 3 different volumes of water with each of two measuring jugs. For each volume with each jug, 2 measurements in randomised order were made: 1) eye-level with the jug, and 2) standing upright (total of 12 measurements). Measured quantities were weighed and the difference between measured and target volumes calculated.

Results

The laboratory jug was more accurate (mean difference 9.3 ml, range − 30.5 to 57.5 ml, std error mean 1.59) than the retail jug (mean difference − 17.7 ml, range − 92.0 to 48.5 ml, std error mean 1.59). Accuracy improved with increased volume (450 ml: mean difference − 9.4 ml, range − 75.5 to 49.5 ml, std error mean 1.95; and 810 ml: mean difference − 0.7 ml; range − 92.0 to 43.0 ml, std error mean 1.95).

Conclusions

Accurate measurement of liquid ingredients is difficult to achieve even for trained professionals. The cumulative effect of many different liquid measurement errors (inappropriate jug type, inaccurate volume measured and poor technique) may lead to clinically important errors in the preparation of modular specialist feeds.

Home enteral tube feeding in children with inherited metabolic disorders: a review of long-term carer knowledge and technique

BACKGROUND

Home enteral tube feeding (HETF) is commonly used in children with inherited metabolic disorders (IMD). It is unclear how caregiver knowledge and their safety in using tube feeding techniques changes over time.

METHODS

Caregivers of children with IMD on HETF from one UK IMD centre had annual interviews over 3 years using a structured questionnaire and observation to assess HETF knowledge and safety techniques.

RESULTS

Thirty-two caregivers of IMD children (median age 5.3 years; range 0.3-13.6 years) were studied. Seventy-eight percent (n = 25) of subjects had been on HETF for >5 years. Over 3 years, many caregivers' HETF techniques deteriorated: accurate feed ingredient measurement decreased from 36% to 11%; correct flushing of tubes decreased from 56% to 44%; checking tube position as recommended decreased from 72% to 56%; and correct hand washing decreased from 38% to 25%. Despite improvements, knowledge of some aspects remained poorly understood: dangers of incorrect tube placement increased from 41% to 56%; correct position for night feeding increased from 38% to 56%; and feed ingredient storage decreased from 87% to 38%.

CONCLUSIONS

The HETF techniques of caregivers of children with IMD declined over time. Caregivers need to understand that HETF, particularly in IMD, is a serious procedure associated with life-threatening risks. Poor HETF practices may cause feed contamination, incorrect feed concentration, feed intolerance, aspiration, peritonitis and even metabolic decompensation. HETF skills should be reassessed annually, with compulsory retraining if basic 'core' HETF competencies are not demonstrated.