Meal Volume Research Articles

Feeding of adult Ornithodoros tartakovskyi ticks using a modified artificial membrane feeding system.

Development and maintenance of laboratory tick colonies provides reliable access to a variety of tick species at multiple life stages. Advances in techniques for the membrane feeding of ticks reduce the number of laboratory animals needed for colony maintenance. In the present study, modifications to the existing protocol for in vitro feeding of the argasid species Ornithodoros tartakovskyi were made. Adult O. tartakovskyi ticks of both sexes were allowed to feed to engorgement using a novel membrane feeding apparatus in a six-well plate format with well-inserts of laboratory-grade, wax sealing film. Of the 193 ticks placed on the membrane, 89% (n = 172) fed until engorgement and subsequently detached. The modified feeding method described will aid in future laboratory tick-based research because it allows for increased containment, ease of sorting, successful in vitro feeding, easy replacement of blood meals and a reduction in the total volume of blood meal required.

Gastric motor and sensory function in health assessed by magnetic resonance imaging: Establishment of reference intervals for the Nottingham test meal in healthy subjects.

Current investigations of gastric emptying rarely identify the cause of symptoms or provide a definitive diagnosis in patients with dyspepsia. This study assessed gastric function by magnetic resonance imaging (MRI) using the modular "Nottingham test meal" (NTM) in healthy volunteers (HVs). The NTM comprises (a) 400mL liquid nutrient (0.75kcal/mL) labeled with Gadolinium-DOTA and (b) an optional solid component (12 agar-beads [0kcal]). Filling sensations were documented. MRI measurements of gastric volume, emptying, contraction wave frequency, and secretion were obtained using validated methods. Gastric function was measured in a population of 73 HVs stratified for age and sex. NTM induced moderate satiety and fullness. Labeled fluid was observed in the small bowel in all subjects after meal ingestion ("early-phase" GE). Secretion was rapid such that postprandial gastric content volume was often greater than meal volume (GCV0>400mL), and there was increasing dilution of the meal during the study (P<0.001). Gastric half-time was median 66-minutes (95% reference interval 35 to 161-minutes ["late-phase" GE]). The number of intact agar beads in the stomach was 7/12 (58%) at 60-minutes and 1/12 (8%) at 120-minutes. Age, bodyweight and sex had measurable effects on gastric function; however, these were small compared to inter-individual variation for most metrics. Reference intervals are presented for MRI measurements of gastric function assessed for the mixed liquid/solid NTM. Studies in patients will determine which metrics are of clinical value and also whether the reference intervals presented here offer optimal diagnostic sensitivity and specificity.

Profilaktyka i terapia żywieniowa w chorobie wrzodowej żołądka

Peptic ulcer disease is considered a very important clinical problem. It is the most frequently occurring gastrointestinal disease entity. It is characterized by the formation of cavities in the gastric mucosa and occurs in people of all ages. The main factor responsible for its development is Helicobacter pylori. There are also many factors responsible for the development of the disease. Genetic predisposition, pathogenicity of H. pylori strain, taking various medications as well as inappropriate diet, rich in stimulants, are indicated. Treatment of the disease consists mainly in the eradication of pathogenic bacteria. This procedure is extremely difficult due to the growing resistance of H. pylori to antibiotics. Therefore, the therapy consists of administering several drugs at the same time. Additionally, during the course of treatment, care should be taken to balance the protective and irritating factors of the gastric mucosa. Proton pump inhibitors are helpful for this purpose. An increasing importance of support is attributed to proper dietary management. It aims to select easily digestible products that do not stimulate the excessive secretion of hydrochloric acid and do not remain in the stomach for a long time. Products stimulating the movement of the stomach are also eliminated in order to reduce pain. In addition to the selection of the right products, the amount and volume of meals, as well as the way of preparing them, are important. The diet in peptic ulcer of the stomach fully covers the energy demand and for minerals and vitamins. Taking into account the antibiotic resistance of pathogenic bacteria, substances of vegetable origin are also more and more often indicated as an important element supporting treatment.

Peripheral venous vs. capillary microfilariaemia in a dog co-infected with Dirofilaria repens and D. immitis: A comparative approach using triatomine bugs for blood collection

Dirofilaria immitis and D. repens are mosquito-borne nematodes, primarily infecting dogs, but also other species of carnivores and even humans. Given their impact on animal and human health, the transmission of these filarioids has been widely studied. The microfilariaemia has been shown to have a circadian variation for both Dirofilaria species infecting dogs. Due to methodological difficulties, the periodicity was only studied using venous blood samples, while the mosquitoes feed, in fact, on capillary blood. In this context, the present study aimed to test the feasibility of using triatomine bugs for the collection of capillary blood and to comparatively evaluate the level of microfilariaemia and its circadian variation in capillary blood vs. peripheral venous blood in a dog naturally co-infected with D. immitis and D. repens. The results showed a feeding success of 50%, with variations in the blood meal volume that the bugs ingested. The relative values of microfilariaemia (mf/bug) were strongly correlated with the volume of blood recovered: the more blood recovered from each bug, the higher values of microfilariaemia in the evening samples while the opposite results were obtained for the morning samples. The counting of microfilariae revealed a dominance of D. immitis in all the samples, but with significantly higher microfilariaemia in the venous blood. Meanwhile, for D. repens, the situation was opposite, with higher counts in the capillary blood samples. Our study showed that triatomine bugs can be used as a model for the collection and study of microfilariaemia in the capillary blood in mammals.

Glucose sensor-augmented continuous subcutaneous insulin infusion in patients with diabetic gastroparesis: An open-label pilot prospective study

Erratic blood glucose levels can be a cause and consequence of delayed gastric emptying in patients with diabetes. It is unknown if better glycemic control increases risks of hypoglycemia or improves hemoglobin A1c levels and gastrointestinal symptoms in diabetic gastroparesis. This study investigated the safety and potential efficacy of continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM) in poorly controlled diabetes with gastroparesis. Forty-five type 1 or 2 patients with diabetes and gastroparesis and hemoglobin A1c >8% from the NIDDK Gastroparesis Consortium enrolled in a 24 week open-label pilot prospective study of CSII plus CGM. The primary safety outcome was combined numbers of mild, moderate, and severe hypoglycemic events at screening and 24 weeks treatment. Secondary outcomes included glycemic excursions on CGM, hemoglobin A1c, gastroparesis symptoms, quality-of-life, and liquid meal tolerance. Combined mild, moderate, and severe hypoglycemic events occurred similarly during the screening/run-in (1.9/week) versus treatment (2.2/week) phases with a relative risk of 1.18 (95% CI 0.85–1.64, P = 0.33). CGM time in hypoglycemia (<70 mg/dL) decreased from 3.9% to 1.8% (P<0.0001), time in euglycemia (70–180 mg/dL) increased from 44.0% to 52.0% (P = 0.02), time in severe hyperglycemia (>300 mg/dL) decreased from 14.2% to 7.0% (P = 0.005), and hemoglobin A1c decreased from 9.4±1.4% to 8.3±1.3% (P = 0.001) on CSII plus CGM. Symptom scores decreased from 29.3±7.1 to 21.9±10.2 with lower nausea/vomiting, fullness/early satiety, and bloating/distention scores (P≤0.001). Quality-of-life scores improved from 2.4±1.1 to 3.1±1.1 (P<0.0001) and volumes of liquid nutrient meals tolerated increased from 420±258 to 487±312 mL (P = 0.05) at 24 weeks. In conclusion, CSII plus CGM appeared to be safe with minimal risks of hypoglycemic events and associated improvements in glycemic control, gastroparesis symptoms, quality-of-life, and meal tolerance in patients with poorly controlled diabetes and gastroparesis. This study supports the safety, feasibility, and potential benefits of improving glycemic control in diabetic gastroparesis.

Gastric emptying of different meal volumes of identical composition in preterm infants: a time series analysis.

BackgroundPreterm infants' meals typically progress to higher volumes over time. Knowledge of gastric emptying (GE) responses to differing meal volumes may inform enteral feeding management. We examined the effect of meal volume and composition on preterm GE.MethodsForty infants were studied at 33.3±1.4 (29.7-35.6) weeks postmenstrual age when fully enteral fed (target 150 ml/kg/day). Intraindividual comparisons of GE were made for paired meals of 100% and 75% prescribed volume and identical composition of mother's own milk (n=21) and pasteurized donor human milk (n=19). Serial stomach ultrasound images were used to calculate gastric residual volumes (GRVs) and remaining meal proportions (% meal).ResultsGE was faster in the early postprandial period and slowed over time (P<0.001). Reduced volume meals had slower GE rates and lower GRV (P<0.001). Serial postprandial % meal was similar between reduced and full volume meals (P=0.41). Higher milk casein concentration was associated with slower GE (P=0.04). Complete gastric emptying (GRV=0 ml) was more common in infants fed at 3 h intervals compared with those fed every 2 h (P=0.002).ConclusionEarly postprandial GE is more rapid for larger meal volumes. Stable preterm infants may tolerate feeding of a 3 h meal volume at shorter intervals.

The newborn rat gastric emptying rate is volume and not developmentally dependent.

Gastric residuals are a common finding in enterally fed preterm neonates and traditionally thought to reflect immaturity-related delayed gastric emptying. Adult human data suggest that the meal volume regulate the gastric emptying rate, but early in life, this has not been adequately evaluated. The goal of this study was to study the rat postnatal changes in gastric emptying rate and the strain-induced effect on muscle contraction. We hypothesized that the stomach content volume and not developmental factors determines the newborn gastric emptying rate, via the Rho-kinase 2 (ROCK-2) pathway. Gastric volume and emptying rate measurements were obtained by ultrasound at different postprandial times and the wall strain-dependent changes in muscle contraction were evaluated ex vivo. The newborn rat gastric emptying rate was unrelated to postnatal age, maximal 30min postprandial, and directly proportional to content volume. In vitro measurements showed that the agonist-induced gastric muscle contraction was directly proportional to the stomach wall strain. These changes were mediated via upregulation of ROCK-2 activity. The newborn rat gastric emptying rate is not developmentally regulated, but dependent on the content volume via wall strain-induced ROCK-2 activation. Further clinical studies addressing the content volume effect on the rate of gastric emptying are warranted, to enhance feeding tolerance in preterm neonates.

Association of Novel Complementary Feeding Indicators with Length‐for‐Age Z‐Scores in Rural Malawi

BackgroundInadequate complementary feeding (CF) from 6–24 months contributes to growth failure in many low income settings. However, recommended indicators of CF are inconsistently associated with length‐for‐age z‐scores (LAZ).ObjectiveTo assess the relationship between novel indicators of CF, including consistency and meal volume, with LAZ in rural Malawi.Methods1,331 households with a child aged 6 to 17 months were sampled from 53 communities in Mchinji district, Malawi using a single stage cluster sampling approach based on caregivers' participation in community women's groups. Data were collected on household sociodemographics, CF practices, and child anthropometry using WHO recommended methods. To assess food consistency, caregivers selected from a series of photographs that which most closely resembled their child's food. Caregivers estimated meal volume using uncooked rice which was then measured; meal volume was then classified as either below or above the age‐specific median for the following age categories: 6–8 months, 9–11 months, and 12–17 months. A summary feeding index (range 0–8 points) was created based on partially or fully meeting WHO recommended CF practices in addition to meal volume and consistency. Length‐for‐age z‐scores, derived from WHO Child Growth Standards, were regressed onto individual CF indicators and the summary feeding index, controlling for covariates. Logistic regression was used to assess the relationship between stunting and scoring in the second or third range of index scores (3–5 and 6–8 points, respectively).ResultsMean child age was 10.8 ± 3.2 months and 51% were female. There was no association between LAZ and minimum dietary diversity (P=0.4), minimum meal frequency (P=0.6), or minimum acceptable diet (P =0.8). There was evidence of interaction between child's age and both food consistency and meal volume. Among 6–8 month old infants, thicker food consistency was positively associated with LAZ (β = 0.14, 95% CI 0.02, 0.27); there was no relationship in older age categories. Meal volume was positively associated with LAZ in children 9–11 months (β = 0.29, 95% CI = 0.04, 0.54) and 12–17 months (β = 0.33, 95% CI = 0.10, 0.56), but not those aged 6–8 months. Each one point increase in the summary feeding index (median=5, IQR=3), was positively associated with LAZ (β = 0.05, 95% CI 0.00, 0.10) and reduced odds of stunting (OR = 0.93, 95% CI 0.87, 1.00). Compared to scoring in the lowest index category, scoring in the middle (3–5 points; OR=0.69, 95% CI 0.46, 1.05) or highest range (6–8 points; OR=0.58, 95% CI 0.38, 0.88) was associated with reduced odds of stunting.ConclusionNovel indicators of CF, such as consistency and meal volume, may be useful to understand the totality of CF and its relation to child growth in low income settings.Support or Funding InformationFunding and support for this research was provided by Concern Worldwide; Malawi Department of Nutrition, HIV and AIDS; World Bank; Emory Global Health Institute; Laney Graduate School, Emory University; and the National Institute of Diabetes and Digestive and Kidney Disease of the National Institutes of Health under award number T32DK007734.

The normal increase in insulin after a meal may be required to prevent postprandial renal sodium and volume losses

Despite the effects of insulinopenia in type 1 diabetes and evidence that insulin stimulates multiple renal sodium transporters, it is not known whether normal variation in plasma insulin regulates sodium homeostasis physiologically. This study tested whether the normal postprandial increase in plasma insulin significantly attenuates renal sodium and volume losses. Rats were instrumented with chronic artery and vein catheters, housed in metabolic cages, and connected to hydraulic swivels. Measurements of urine volume and sodium excretion (UNaV) over 24 h and the 4-h postprandial period were made in control (C) rats and insulin-clamped (IC) rats in which the postprandial increase in insulin was prevented. Twenty-four-hour urine volume (36 ± 3 vs. 15 ± 2 ml/day) and UNaV (3.0 ± 0.2 vs. 2.5 ± 0.2 mmol/day) were greater in the IC compared with C rats, respectively. Four hours after rats were given a gel meal, blood glucose and urine volume were greater in IC rats, but UNaV decreased. To simulate a meal while controlling blood glucose, C and IC rats received a glucose bolus that yielded peak increases in blood glucose that were not different between groups. Urine volume (9.7 ± 0.7 vs. 6.0 ± 0.8 ml/4 h) and UNaV (0.50 ± 0.08 vs. 0.20 ± 0.06 mmol/4 h) were greater in the IC vs. C rats, respectively, over the 4-h test. These data demonstrate that the normal increase in circulating insulin in response to hyperglycemia may be required to prevent excessive renal sodium and volume losses and suggest that insulin may be a physiological regulator of sodium balance.

Invited review: Abomasal emptying in calves and its potential influence on gastrointestinal disease

Creating the ideal nutrition program for calves is a demanding task that has undergone tremendous change in recent years. Products and technologies including novel milk replacers and automated calf feeding systems have been developed to facilitate the ability of dairy producers to feed for higher growth rates before weaning. The creation of new feeding programs and milk replacers has to be looked at carefully, not only from a nutrition point of view but also from the perspective of a potential effect on physiologic digestion and calf health. Abomasal emptying is a critical factor that may link nutrition and disease. The purpose of this article is to review both intrinsic and extrinsic factors that are responsible for abomasal emptying. Predominant extrinsic factors controlling abomasal emptying include meal volume, energy density, and osmolality along with the content and source of protein. This article also reviews experimental methods used to measure abomasal emptying in the calf including those that would be appropriate for use under field conditions. Among these methods, the use of ultrasonography and different absorption tests (d-xylose, acetaminophen) as tools to measure abomasal emptying are discussed. The relationship between abomasal emptying and disease is explored, particularly as it relates to abomasal bloat. Abomasal bloat is a complex syndrome that seems to be increasing in frequency and whose etiology likely at least partially involves slowing of abomasal emptying. Suggestions for minimizing the effect of feeding programs on abomasal emptying are explored as well as needs for future research.

Differential brain responses to gradual intragastric nutrient infusion and gastric balloon distension: A role for gut peptides?

BackgroundRapid gastric balloon distension to discomfort threshold activates the “pain neuromatrix” and deactivates exteroceptive sensory and “default mode network” regions. However, little is known about brain mechanisms underlying tolerance of meal-induced gastric distension. We aimed to directly compare brain responses to gradual balloon distension and intragastric nutrient infusion and to explore the role of differential gut peptide release in these responses. Materials and methodsBrain responses to balloon- and nutrient-induced distension (to individually titrated pain or maximal satiation threshold) were measured in 15 healthy volunteers using H215O-PET on 2 separate days in counterbalanced order. The effects of increasing gastric distension and plasma levels of ghrelin and peptide YY3-36 (PYY3-36) on neural activity were assessed. ResultsBalloon distension progressively activated pain-responsive regions and deactivated exteroceptive sensory and “default mode network” areas. During nutrient infusion, “pain neuromatrix” regions and the orbitofrontal cortex were progressively deactivated, while the midbrain was activated. Plasma levels of PYY3-36 and ghrelin increased and decreased, respectively, during nutrient infusion only; decreasing ghrelin levels correlated with increasing midbrain activity. ConclusionDifferent brain responses to gastric balloon distension and intragastric nutrient infusion are associated with nutrient-induced gut-brain signals, particularly to the midbrain, where these signals may interfere with both descending pain modulatory and mesolimbic reward processes. Deactivation of the “pain neuromatrix” during nutrient infusion may constitute the neurophysiological mechanism underlying the tolerance of normal meal volumes in health without induction of (painful) symptoms. Nutrient-induced deactivation of the orbitofrontal cortex may represent a key interoceptive meal termination signal.

Issue Highlights

Issue Highlights

Evaluation of the acceptability of improved supplementary foods for the treatment of moderate acute malnutrition in Burkina Faso using a mixed method approach

The objective of this study was to evaluate, within the context of a randomized controlled trial of product effectiveness, the acceptability of new formulations of six corn-soy blended flours (CSB) and six lipid-based nutrient supplements (LNS) with different quantities of milk and qualities of soy for the treatment of children with moderate acute malnutrition (MAM).Our study included 1546 children aged 6–23 months and involved questionnaires after one month of supplementation home visits and interviews with a sub-sample of 20 trial participants and their caretakers, and nine focus group discussion.All 12 products were well accepted in terms of organoleptic qualities and received good ratings. However, LNS were more appreciated by caretakers and children. Additionally, an effect of soy isolate was detected on child appreciation where products with high milk content also received better ratings. CSB were not consumed as readily; 33.9% (n = 257) of children receiving CSB were reported to have leftovers compared to 17.3% (n = 134) of children receiving LNS (p=<0.001). Both CSB and LNS were referred to as foods with medicinal properties and perceived as beneficial to child health. They were both reported to have high priority in the daily feeding of the child.In conclusion, there were minimal differences in acceptability of the various CSB and LNS formulations, although CSB were less readily consumed and required smaller meal volumes. Since all products were well-accepted, decisions regarding whether the more expensive products should be used for the treatment of MAM will need to be based on their effect on child nutrition, growth and health. Future supplementary feeding programs in similar contexts could furthermore consider introducing supplementary foods as a medical treatment, as this may increase adherence and decrease sharing.

The relationship between wing length, blood meal volume, and fecundity for seven colonies of Anopheles species housed at the Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand

Established colonies of Anopheles campestris, Anopheles cracens, Anopheles dirus, Anopheles kleini, Anopheles minimus, Anopheles sawadwongporni, and Anopheles sinensis are maintained at the Armed Forces Research Institute of Medical Sciences (AFRIMS). Females were provided blood meals on human blood containing citrate as an anticoagulant using an artificial membrane feeder. The mean wing length, used as an estimate of body size, for each species was compared to blood-feeding duration (time), blood meal volume, and numbers of eggs oviposited. Except for An. campestris and An. cracens, there were significant interspecies differences in wing length. The mean blood meal volumes (mm3) of An. kleini and An. sinensis were significantly higher than the other 5 species. For all species, the ratios of unfed females weights/blood meal volumes were similar (range: 0.76–0.88), except for An. kleini (1.08) and An. cracens (0.52), that were significantly higher and lower, respectively. Adult females were allowed to feed undisturbed for 1, 3, and 5min intervals before blood feeding was interrupted. Except for An. campestris and An. sawadwongporni, the number of eggs oviposited were significantly higher for females that fed for 3min when compared to those that only fed for 1min. This information is critical to better understand the biology of colonized Anopheles spp. and their role in the transmission of malaria parasites as they relate to the relative size of adult females, mean volumes of blood of engorged females for each of the anopheline species, and the effect of blood feeding duration on specific blood meal volumes and fecundity.

The most common errors in the management of gastroesophageal reflux

Gastro-Esophageal Reflux (GER) occurs in more than two-thirds of otherwise healthy children and is one of the major reason for referral to paediatricians; in fact, a quarter of all paediatric visits in the first six months of life [1] and numerous accesses to the paediatric gastroenterologist services are secondary to GER. GER is defined as the passage of gastric contents into the esophagus and is different from gastroesophageal reflux disease (GERD), which includes all the symptoms and/or complications associated with GER [2]. GER is considered a physiological normal process which occurs several times a day in healthy infants, children and adults. GER is usually associated with transient lower esophageal sphincter relaxations independent from swallowing, which allow the passage of gastric contents into the esophagus. Episodes of GER in healthy adults tend to occur after meals, lasting less than three minutes and usually do not cause symptoms. Although we know less on the normal physiology of newborns and infants, regurgitation is the most visible symptom and tends to occur daily in 50% of all infants with a peak incidence between 4 and 6 months of life [3]. For the majority of paediatric patients (especially in infants), the clinical history and the objective appraisal, in the absence of danger signals, are sufficient to reliably diagnose a not complicated GER and initiate conservative treatment strategies; in general, the diagnostic tests are not always necessary. The reliability of the symptoms to make the clinical diagnosis of GERD is higher in children younger than 8 years, reporting heartburn: only in this case, the doctor can make a diagnosis of Gastro Esophageal Reflux Syndrome and give an indication for therapy [4]. To date, no single symptom or set of symptoms can be trusted, and then used to diagnose GERD in children or to predict which patients are more likely to respond to therapy [2]. The only exception is the child (age> 8y.o.) reporting a history of long-term heartburn with or without vomiting. The new ESPGHAN/NASPGHAN guidelines [2] describe different treatment options for the treatment of infants / children with GER and GERD. In particular, they emphasized the changes in lifestyle, because it can effectively reduce the symptoms of both infants and children. They are based on a combination of changes of milk formulas and positional therapy. In infants with GER, it can be effective the changes to the mother's diet if children are breastfed, change the formula in use, reducing the volume of the single meal associated with an increased frequency of feedings. In particular, the guidelines stress that the allergy to milk proteins may have a clinical presentation similar to GERD. A strategy of nutritional intervention involves the use of thickened formulas that are able to decrease the regurgitation. A recent meta-analysis has shown that the anti regurgitation formula have the following functions: a) increase the number of infants without regurgitation; b) reduce the number of episodes of regurgitation and vomiting daily; c); increase the weight recovery of the infant, d) although they do not change the 24 hours pH study [4].

Effect of Exercise Intensity on Subsequent Gastric Emptying Rate in Humans.

Previous investigations have suggested that exercise at intensities greater than 70% maximal oxygen uptake (VO2max) reduces gastric emptying rate during exercise, but little is known about the effect of exercise intensity on gastric emptying in the postexercise period. To examine this, 8 healthy participants completed 3 experimental trials that included 30 min of rest (R), low-intensity (L; 33% of peak power output) exercise, or high-intensity (H; 10 × 1 min at peak power output followed by 2 min rest) exercise. Thirty minutes after completion of exercise, participants ingested 595 ml of a 5% glucose solution, and gastric emptying rate was assessed via the double-sampling gastric aspiration method for 60 min. No differences (p > .05) were observed in emptying characteristics for total stomach volume or test meal volume between the trials, and the quantity of glucose delivered to the intestine did not differ between trials (p > .05). Half-emptying times did not differ (p = .902) between trials and amounted to 22 ± 9, 22 ± 9, and 22 ± 7 min (M ± SD) during the R, L, and H trials, respectively. These results suggest that exercise has little effect on postexercise gastric emptying rate of a glucose solution.

On the validity of the 13C‐acetate breath test for comparing gastric emptying of different liquid test meals: a validation study using magnetic resonance imaging

(13) C-acetate breath testing (BT) is applied to assess and compare gastric emptying of liquid meals. Gastric half-emptying times (t50 ) from BT show offsets compared to t50 values from γ-scintigraphy and ultrasonography. Linear transformations have been proposed to correct these offsets. This investigation critically validates the BT for the assessment of liquid gastric emptying by using simultaneously recorded meal and total gastric content volume emptying data from magnetic resonance imaging (MRI). Data were collected during a recently published double-blind, randomized, cross-over MRI gastric emptying study of three (13) C-labeled enteral formulas differing in protein sources (PMID: 24699556). Breath testing-derived t50 was computed with the analysis methods commonly applied in gastric emptying research, i.e., the exponential-beta function and the Wagner-Nelson (WN) method, respectively. Breath testing t50 values from exponential-beta function and WN method showed a positive and negative offset to MRI data, respectively. Linear regression detected low concordance between MRI and both BT methods revealing meal specific and emptying rate-dependent offsets. The WN method showed worse agreement and correlation with MRI emptying data. Breath testing rather reflected meal volume than total gastric content volume emptying. This validation study indicates that the (13) C-acetate breath test may not be applied to compare gastric emptying of arbitrary liquid meals without prior validation by imaging methods. t50 values from BT are biased by (i) the properties of the meal and (ii) the selected method used for (13) CO2 exhalation analysis. No linear transformation common for all meals was applicable to correct the offsets between BT and MRI.

Energy‐Dense Formulae May Slow Gastric Emptying in the Critically Ill

Enteral feed intolerance occurs frequently in critically ill patients and can be associated with adverse outcomes. "Energy-dense formulae" (ie, >1 kcal/mL) are often prescribed to critically ill patients to reduce administered volume and are presumed to maintain or increase calorie delivery. The aim of this study was to compare gastric emptying of standard and energy-dense formulae in critically ill patients. In a retrospective comparison of 2 studies, data were analyzed from 2 groups of patients that received a radiolabeled 100-mL "meal" containing either standard calories (1 kcal/mL) or concentrated calories (energy-dense formulae; 2 kcal/mL). Gastric emptying was measured using a scintigraphic technique. Radioisotope data were collected for 4 hours and gastric emptying quantified. Data are presented as mean ± SE or median [interquartile range] as appropriate. Forty patients were studied (n = 18, energy-dense formulae; n = 22, standard). Groups were well matched in terms of demographics. However, patients in the energy-dense formula group were studied earlier in their intensive care unit admission (P = .02) and had a greater proportion requiring inotropes (P = .002). A similar amount of calories emptied out of the stomach per unit time (P = .57), but in patients receiving energy-dense formulae, a greater volume of meal was retained in the stomach (P = .045), consistent with slower gastric emptying. In critically ill patients, the administration of the same volume of a concentrated enteral nutrition formula may not result in the delivery of more calories to the small intestine over time because gastric emptying is slowed.

Food, the Immune System, and the Gastrointestinal Tract

Food, the Immune System, and the Gastrointestinal Tract

Acceptability and utility of an innovative feeding toolkit to improve maternal and child dietary practices in Bihar, India.

Dietary practices in India often fail to provide adequate nutrition during the first 1,000 days of life. To explore the acceptability and utility of a low-cost and simple-to-use feeding toolkit consisting of a bowl with marks to indicate meal volume and frequency, a slotted spoon, and an illustrated counseling card to cue optimal dietary practices during the first 1,000 days. In Samastipur District, Bihar, India, we conducted 16 focus group discussions and 8 key informant interviews to determine community acceptability and obtain feedback on design and delivery of the feeding toolkit. We conducted 14 days of user testing with 20 pregnant women, 20 breastfeeding women 0 to 6 months postpartum, and 20 mothers with infants 6 to 18 months of age. The toolkit, which is made of plastic, was well accepted by the community, although the communities recommended manufacturing the bowl and spoon in steel. The proportion of pregnant and breast-feeding women taking an extra portion of food per day increased from 0% to 100%, and the number of meals taken per day increased from two or three to three or four. For children 6 to 18 months of age, meal frequency, quantity of food consumed during meals, and thickness of the foods increased for all age groups. Children 6 to 8 months of age who had not yet initiated complementary feeding all initiated complementary feeding during the testing period. Simple feeding tools are culturally acceptable and can be appropriately used by families in Bihar, India, to improve dietary practices during the first 1,000 days of life. Research is needed to assess whether the tools promote dietary and nutritional improvements over and above counseling alone.