Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-25T01:06:24.194Z Has data issue: false hasContentIssue false
  • English
  • Français

Importance of measuring CO2-production rate when using 13C-breath tests to measure fat digestion

Published online by Cambridge University Press:  09 March 2007

S. Amarri ,
W. A. Coward ,
M. Harding  and
L. T. Weaver
S. Amarri*
Affiliation:
Department of Paediatrics, University of Modena, Italy
W. A. Coward
Affiliation:
MRC Dunn Nutrition Unit, Cambridge, UK
M. Harding
Affiliation:
MRC Dunn Nutrition Unit, Cambridge, UK
L. T. Weaver
Affiliation:
Department of Child Health, University of Glasgow, Yorkhill Hospitals, Glasgow, UK
*
*Corresponding author:Dr S. Amarri, fax +39 59 424583, email [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Stable isotope breath tests offer a safe, repeatable non-invasive method of measuring fat digestion. They involve the ingestion of a substrate labelled with 13C followed by serial measurements of the 13C: 12C ratio in expired CO2, from which the percentage of the 13C dose recovered (PDR) can be calculated. However PDR depends on the CO2-production rate. Our aim was to compare results obtained using directly measured CO2-production rates with those calculated from two predicted values. Twelve normal healthy children and twenty-four children with cystic fibrosis (CF) (without or with the normal dose of enzyme supplementation) were studied with 1,3-distearyl, 2[carboxyl[13C]octanoyl glycerol. The volume of CO2 produced (litres/min) was measured at rest for 30 min approximately 3 h after substrate ingestion, and the results were converted to mmol/min. For each subject the expected BMR was calculated from the equation of Schofield (1985), based on sex, age, weight and height, and from these values, CO2-production rate was derived. Surface area was calculated and an estimated value of 5 mmol/m2 per min (Shreeve et al. 1970) was used. Using these three CO2-production rates, three different PDR were calculated and compared. In healthy children there was a close concordance between measured and predicted CO2-production rates, but children with CF had a mean measured CO2-production rate 39% higher than normal children. This use of normal data for predicted CO2-production rates in children with CF underestimates cumulative PDR. If direct measurements of CO2-production rate are not available or impossible to perform the Vco2 obtained from the BMR calculated using the equations of Schofield (1985) or Shreeve et al. (1970) can be used in normal children. However, if accurate results for PDR are to be obtained, CO2-production rates should be measured when performing breath tests in conditions where energy expenditure and/or CO2-production rate are not expected to be normal.

Keywords

13C-Breath testsStable isotopesCystic fibrosis
Type
Technical Note
Information
British Journal of Nutrition , Volume 79 , Issue 6 , June 1998 , pp. 541 - 545
Copyright
Copyright © The Nutrition Society 1998

References

Amarri, S & Weaver, LT (1995) 13C-breath tests to measure fat and carbohydrate digestion in clinical practice. Clinical Nutrition 14, 149–154.CrossRefGoogle Scholar
Amarri, S, Harding, M, Coward, WA, Evans, TJ, Paton, JY & Weaver, LT (1995) 13C and H2 breath tests to study extent and site of starch digestion in cystic fibrosis. Journal of Pediatric Gastroenterology and Nutrition 20, 448.Google Scholar
Amarri, S, Harding, M, Coward, AW, Evans, TJ & Weaver, LT (1997) 13C mixed triglyceride breath test and pancreatic enzyme supplementation in children with cystic fibrosis. Archives of Disease in Childhood 76, 349–351.CrossRefGoogle Scholar
Bland, JM & Altman, DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet i, 307–310.CrossRefGoogle Scholar
Buchdahl, RM, Cox, M, Fulleylove, C, Marchant, JL, Tomkins, AM, Brueton, MJ & Warner, JO (1988) Increased energy expenditure in cystic fibrosis. Journal of Applied Physiology 64, 1810–1816.CrossRefGoogle ScholarPubMed
Castlemead Growth Program (1993) Welwyn Garden City, UK: Castlemead Publications.Google Scholar
Elia, M (1990) The estimation of short-term energy expenditure by the labelled bicarbonate method. In New Techniques in Nutrition Research, pp. 207–232 [Whitehead, RG and Prentice, AM, editors]. London: Academic Press.Google Scholar
Elia, M & Livesey, G (1988) Theory and validity of indirect calorimetry during net lipid synthesis. American Journal of Clinical Nutrition 47, 591–607.CrossRefGoogle ScholarPubMed
Ghoos, YF, Maes, BD, Geypens, BJ, Mys, G, Hiele, MI, Rutgeerts, PJ & Vantrappen, G (1993) Measurement of gastric emptying rate of solids by means of a carbon-labelled octanoic acid breath test. Gastroenterology 104, 1640–1647.CrossRefGoogle Scholar
Graham, DY, Klein, PD, Evans, DJ, Evans, DG, Alpert, LC, Opekun, AR & Boutton, TW (1987) Campylobacter pyloridis detected noninvasively by the 13C-urea breath test. Lancet i, 1174–1177.CrossRefGoogle Scholar
Haycock, GB, Schwartz, GJ & Wisotsky, DH (1978) Geometric method for measuring body surface area: a height: weight formula validated in infants, children and adults. Journal of Pediatrics 93, 62–66.CrossRefGoogle ScholarPubMed
Kalivianakis, M, Verkade, HJ, Stellard, F, Van der, Werf M, Elzinga, H & Vonk, RJ (1997) The 13C-mixed triglyceride breath test in healthy adults: determinants of the CO2 response. European Journal of Clinical Investigation 27, 434–442.CrossRefGoogle Scholar
Leijssen, DPC & Elia, M (1996) Recovery of 13C and 14CO2 in human bicarbonate studies: a critical review with original data. Clinical Science 91, 665–677.CrossRefGoogle ScholarPubMed
Matthews, JNS, Altman, DG, Campbell, MJ & Royston, P (1990) Analysis of serial measurements in medical research. British Medical Journal 300, 230–235.CrossRefGoogle ScholarPubMed
McClean, P, Harding, M, Coward, WA, Green, MR & Weaver, LT (1993) Measurement of fat digestion in early life using a stable isotope breath test. Archives of Disease in Childhood 69, 366–370.CrossRefGoogle ScholarPubMed
Metges, CC & Wolfram, G (1991) Medium and long chain triglycerides labelled with 13C: a comparison of oxidation after oral and parenteral administration in humans. Journal of Nutrition 121, 31–36.CrossRefGoogle ScholarPubMed
Murphy, MS, Eastham, EJ, Nelson, R & Aynsley-Green, A (1990) Non-invasive assessment of intraluminal lipolysis using a 13CO2 breath test. Archives of Disease in Childhood 65, 574–578.CrossRefGoogle ScholarPubMed
Pallikarakis, N, Sphiris, N & Lefebvre, P (1991) Influence of the bicarbonate pool and on the occurrence of 13CO2 in exhaled air. European Journal of Applied Physiology 63, 179–183.CrossRefGoogle ScholarPubMed
Schofield, WN (1985) Predicting basal metabolic rate, new standards and review of previous work. Human Nutrition: Clinical Nutrition 39C, 5–41.Google ScholarPubMed
Shreeve, VW, Cerasi, E & Luft, R (1970) Metabolism of (2-14C) pyruvate in normal, acromegalic and HGH-treated human subjects. Acta Endocrinologica 65, 155–169.Google ScholarPubMed
Tanner, JM, Whitehouse, RH & Takaishi, M (1966) Standards from birth to maturity for height, weight, height velocity, and weight velocity: British children, 1965. Archives of Disease in Childhood 41, 454–471.CrossRefGoogle ScholarPubMed
Vantrappen, GR, Rutgeerts, P, Ghoos, YF & Hiele, MI (1989) Mixed triglyceride breath test: a noninvasive test of pancreatic lipase activity in the duodenum. Gastroenterology 96, 1126–1134.CrossRefGoogle ScholarPubMed
Weaver, LT, Thomas, JE, McClean, P, Harding, M & Coward, WA (1993) Stable isotope breath tests: their use in paediatric practice. In Progress in Understanding and Management of Gastro-intestinal Motility Disorders, pp. 155–168 [Janssens, J, editor]. University of Leuven: Department of Medicine.Google Scholar
Weaver, LT, Dibba, B, Sonko, B, Bohane, TD & Hoare, S (1995) Measurements of starch digestion of naturally 13C-enriched weaning foods, before and after partial digestion with amylase-rich flour, using a 13C breath test. British Journal of Nutrition 74, 531–537.CrossRefGoogle ScholarPubMed