PEDIATRICS Vol. 109 No. 3 March 2002, pp. 457-459
The Significance of Gastric Residuals in the Early Enteral Feeding Advancement of Extremely Low Birth Weight Infants
* Division of Neonatology and Pediatric Critical Care Medicine, Department of Pediatrics, University of Ulm, Ulm, Germany
KZVA-Kinderklinik, Augsburg, Germany
Department of Pediatrics, University of Bonn, Germany
|| Department of Pediatrics, Medical Academy of Dresden, Germany
¶ Department of Pediatrics, University of Münster, Germany
# Department of Pediatrics, University of Rostock, Germany
** Department of Pediatrics, University of Würzburg, Germany
Department of Biometry and Medical Documentation, University of Ulm, Germany
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ABSTRACT |
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 TOP ABSTRACT INTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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Objective. To evaluate whether the mean gastric residual volume (GRV) and green gastric residuals (GR) themselves are significant predictors of feeding intolerance in the early enteral feeding advancement in extremely low birth weight (ELBW; <1000 g) infants.
Design. Ninety-nine ELBW infants were fed following a standardized protocol (day 3–14). At 48 hours of age, milk feeding was started (12 mL/kg/d increments, 12 meals per day). GR were checked before each feeding, and a GRV up to 2 mL/3 mL in infants 
750 g/>750 g was tolerated. In cases of increased GRV, feedings were reduced or withheld. The color of GR was assessed as clear, milky, green-clear, green-cloudy, blood-stained, or hemorrhagic. Multiple regression analysis was used to study the effect of the mean GRV and the color of GR on the feeding volume on day 14 (V14).
Results. The median V14 was 103 mL/kg/d (0–166). V14 increased with an increasing percentage of milky GR, whereas the mean GRV and the color green did not have a significant effect.
Conclusions. 1) Early enteral feeding could be established in ELBW infants. The critical GRV seems to be above 2 mL/3 mL because there was no significant negative correlation between the mean GRV and V14. 2) Green GR were not negatively correlated with V14 and should not slow down the advancement of feeding volumes in absence of other clinical signs and symptoms.
Key Words: infant nutrition • extremely low birth weight infant • gastric residual
Abbreviations: GR, gastric residuals • VLBW, very low birth weight, birth weight less than 1500 g • GRV, gastric residual volume • NEC, necrotizing enterocolitis • ELBW, extremely low birth weight, birth weight less than 1000 g • V14, feeding volume on day 14
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INTRODUCTION |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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It is common practice to check the gastric residuals (GR) before each feeding in very low birth weight (VLBW) infants. The gastric residual volume (GRV) is regarded as an objective parameter for intestinal tolerance of feeding. Increased pregavage residuals are regarded as one of the gastrointestinal manifestations of stage I (suspected) necrotizing enterocolitis (NEC).1,2 The definition of increased GR, however, and its relation to feeding tolerance has never been studied in a systematic manner in early enteral feeding advancement in extremely low birth weight (ELBW;
1000 g) infants. The presence of green GR often prompts the initiation of medical diagnostic procedures, but the significance of green GR and its impact on feeding tolerance has also not been studied in ELBW infants.
In a multicenter trial on early enteral feeding advancement in ELBW infants feedings were advanced following a strict standardized protocol.3 GR up to 2 mL in infants 750 g and up to 3 mL in infants from 750 to 1000 g were tolerated. Feedings were decreased or withheld if the GRV exceeded these preset criteria. The color of the GR did not influence the feeding strategy.
Based on our clinical experience, we hypothesized that our preset gastric residual thresholds (2 mL/3 mL) were too low and that green GR by themselves as opposed to other colors were not a significant predictor of early enteral feeding intolerance in absence of other clinical signs and symptoms.
The aim of this analysis was to evaluate whether a high mean gastric residual volume and green GR by themselves were significantly associated with early feeding intolerance.
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METHODS |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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The present study was part of a randomized, multicenter trial comparing 2 different preterm infant formulas for the early enteral feeding advancement of ELBW infants.3 The protocol was approved by the University of Ulm Review Board on Human Investigation. Informed written parental consent was obtained. Exclusion criteria were major congenital malformations and known gastrointestinal abnormalities. Complementary parenteral nutrition was gradually decreased with increasing enteral intake. The study period covered the first 2 weeks of life.
Feeding Protocol
At 48 hours of age, bolus gavage milk feeding was started (nasogastric tube). Human milk feeding was encouraged, and formula was fed if human milk was not available. Human milk (from the infants’ mothers) was cultured daily and raw human milk was replaced by formula if more than 105 organisms per mL were grown. The infants were fed every 2 hours, starting at 12 mL/kg birth weight/d. Feedings were advanced every 24 hours by 12 mL/kg birth weight/d whenever >50% of the calculated amount was given during the previous 24 hours.
GR were checked before each feeding. Every 2 hours gentle massage to the abdomen of the infants was applied by the nurses to make sure that the tip of the nasogastric tube was not adhering to the wall of the stomach while they were aspirating the GR. In infants 750 g a GRV up to 2 mL was tolerated and the scheduled feed was given; with GRV above 2 mL the difference up to the scheduled feed had been given (eg, 600 g infant, GRV = 3 mL, scheduled feed = 7 mL milk: 7 mL–3 mL = 4 mL to feed); no milk had been given if the GRV was above 2 mL and the volume of the feed was equal to or less than the GRV (eg, 600 g infant, GRV = 6 mL, scheduled feed = 6 mL milk: no milk to feed).
In infants from 751 to 1000 g, a GRV up to 3 mL was tolerated and the scheduled feed was given; with GRV above 3 mL the difference up to the scheduled feed had been given; no milk had been fed if the GRV was above 3 mL and the volume of the feed was equal to or less than the GRV.
The color of the GR, the subjective impression of those in charge and clinical conditions such as hypotension, infection, mild abdominal distension, or Indomethacin therapy did not influence the feeding strategy. After extubation or intubation, feedings were withheld for 6 hours. Feeding were withheld for at least 5 days after surgery and for 10 days in case of NEC stage 
2.
Data Collection
Demographic variables were recorded for all infants. Every second hour, beginning at 48 hours of age and ending after the 14th day of life, vomiting, GRV, the color of GR, and the feeding volume were recorded. The color of GR was assessed as clear (mucous), milk-colored, green-clear, green-flaky, blood-stained, or hemorrhagic. NEC stage 2 was defined according to the Bell stages.1
Data Analysis
For the whole group of surviving infants, the median daily feeding volume was calculated. For every infant, the mean GRV and the percentage of assessments of any GR color were calculated. A multiple linear regression model was assessed to the data after checking for normality by normal probability plots. With a backward selection strategy the impact of the mean GRV and of the percentages of assessments of every GR color on the feeding volume on day 14 (V14) were evaluated. The level of significance of staying in the model was set to P = .05. The data were analyzed using SAS 6.12 (SAS Institute Inc, Cary, NC). Data are shown as median (minimum-maximum).
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RESULTS |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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One hundred fifty-two ELBW infants were admitted to the 7 participating units within the study period, and 53 were excluded for the following reasons: death within the first 2 days of life (N = 19), incorrect randomization (N = 15; 15 consecutively enrolled infants in 1 study center received the same formula without randomization), nonenrollment for unknown reason (N = 5), bad general condition (N = 6), transfer to another hospital within the study period (N = 4), NEC on the first day of life before randomization (N = 1), suspected trisomia 18 (N = 1), and small number of infants (N = 2; one study center enrolled only 2 infants; this center was excluded).
Ninety-nine infants were enrolled in the study. Gestational age was 26 weeks (23–33), birth weight was 820 g (362–990 g), 40 infants were small for gestational age (birth weight less than the tenth perentile), and 84 infants were delivered by caesarean section.
In 59 of the 99 ELBW infants, the feeding volume was advanced according to the protocol by 12 mL/kg/d on at least 10 of 12 study days and on the final study day (day 14) the median feeding volume was 103 (0–166) mL/kg birth weight. NEC (Bell stage 2) occurred in 5 infants within the study days 6 to 9. All cases of NEC were diagnosed by absent bowel sounds, abdominal tenderness, and pneumatosis intestinalis. Within the 24 hours before NEC was diagnosed, the mean GRV was 1.2 (0.7–2.5) mL. In addition, laparotomy was performed in 5 infants for the following reasons: meconium ileus (N = 1), meconium ileus together with perforated microcolon (N = 3), and large subcapsular hematoma of the liver (N = 1). The V14 was zero in all of them. Three infants died within the study period for the following reasons: severe respiratory distress syndrome (N = 2) and intracranial hemorrhage into the posterior fossa (N = 1).
All surviving infants (N = 96) were included in the final analysis. In every infant a median number of 144 (24–144) GR were checked. A total number of 12 924 were checked. In 44.4% (0%–100%) of the time, the GRV was zero. The percentage of the GR colors was: clear 3.3% (0%–42.3%), milky 36.0% (0%–81.2%), green-clear 8.9% (0%–43.0%), green-cloudy 5.2% (0%–55.2%), bloodstained 0.2% (0%–4.2%), and hemorrhagic 1.8% (0%–63.9%). The regression analysis (Table 1) showed that the V14 increased significantly with an increasing percentage of negative (GRV = 0) or milky GR. The mean GRV and colors other than milky did not have a significant impact on V14. One percent (0.01) increase in the percentage of milky GR increased V14 by 2.04 mL and 1% (0.01) increase in the percentage of negative GR (GRV = 0) increased V14 by 0.74 mL.
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DISCUSSION |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
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In VLBW infants, feeding tolerance algorithms are based on preprandial GRV measurement and a high preprandial GRV or green GR are regarded as a significant marker of feeding intolerance. However, several dynamic and fixed definitions of increased GRV have been used. For example, feeding intolerance was defined as a GRV of more then 20% of the volume given in the 4 preceding hours,4 more than 50%5,6 or 20%7,8 of a 3-hour feeding volume (bolus tube-feeding every 3 hours), or more than 30%9 or 20%8,10 of a 2-hour feeding volume (bolus tube-feeding every 2 hours), or as a total GRV from the previous day greater than 10% of the feedings.11 Fixed definitions of feeding intolerance were a GRV of more than 2 mL of undigested formula,12 more than 2 mL or bilious-colored,13 or more than 3 mL/kg or green-colored.14 None of these definitions has been shown to be superior to another in a randomized, controlled trial.
In the present study, the feeding tolerance algorithm was based only on the gastric residual volume that was assessed before each feeding. Using a fixed definition of an increased GRV (2 mL/3 mL), there was no correlation between the average GRV and V14. Two important points might account for this observation: The definition of feeding intolerance (increased GR) itself and the reliability of the measurement of the GRV.
If there was a critical GRV less than our GRV thresholds (2 mL/3 mL), there should be a significant negative correlation between the mean GRV and V14. The V14 should decrease with increasing mean GRV. Because there was no correlation, we concluded that the GRV thresholds could be increased. However, there may be an association between the velocity of daily feeding advancement and the GRV threshold. More rapid feeding advancement than in the present study (ie, >12 mL/kg birth weight/d) may require different GRV thresholds.
With regard to the reliability of the measurement of the GRV, the variability of the present technique of aspirating the GR has not been evaluated. In a study on the effect of body position on GRV,15 the reliability of the measurement of the GRV by aspiration was evaluated. When measured in only one position (right lateral position, prone, or supine) the aspirated GRV underestimated the total GRV by 25% on average and the variability increased as total GRV decreased. Therefore, the technique of extracting the GR might have been be too inaccurate to use to use the GRV as a significant predictor of early feeding intolerance.
In the present study, the majority of GR were of milky color, which has been reported by others as well.5 Colors other than milky had no impact on the feeding volume. Therefore, in the absence of other clinical signs and symptoms, green GR by themselves, at a volume <2 mL/3 mL were not a significant sign of feeding intolerance. A certain amount of duodeno-gastral reflux seemed to be normal. However, the total goodness of fit of the multiple regression model r2 was 0.30, indicating that only 30% of the variability of V14 was predicted by the GRV and its color. Finally, it is a limitation of the study that the statistical analysis was done on a posthoc basis and not with a sample size determination of an a priori hypothesis.
With regard to the NEC (Bell stage 2) incidence of the present study (5%, 95% confidence interval 1.7% to 11.4%), which was in agreement with a recent American Neonatal Research Network report,16 the feeding protocol seemed to be safe. Additional research is required to show whether higher GRV thresholds will permit more rapid feeding advancement in ELBW infants without adverse effects. In an ongoing trial on early enteral nutrition of VLBW infants, the tolerated GRV was increased up to 5 mL/kg body weight.
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ACKNOWLEDGMENTS |
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This study was supported by the Milupa GmbH and Co KG, Friedrichsdorf, Germany.
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FOOTNOTES |
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Received for publication Apr 16, 2001; Accepted Aug 23, 2001.
Reprint requests to (F.P.) Universitäts-Kinderklinik, 89070 Ulm, Germany. E-mail: frank.pohlandt{at}medizin.uni-ulm.de
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REFERENCES |
|---|
|
TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
- Bell MJ, Ternberg JL, Feigin RD, et al. Neonatal necrotizing enterocolitis. Therapeutic decisions based upon clinical staging. Ann Surg.1978; 187 :1 –7[Medline]
- Walsh MC, Kliegman RM. Necrotizing enterocolitis: treatment based on staging criteria. Pediatr Clin North Am.1986; 33 :179 –201[Medline]
- Mihatsch WA, von Schoenaich P, Fahnenstich H, et al. Randomized multi-center trial of two different formulas for very early enteral feeding advancement in extremely low birth weight infants. J Pediatr Gastroenterol Nutr.2001; 33 :155 –159[Medline]
- Dollberg S, Kuint J, Matzkereth R, Mimouni FB. Feeding tolerance in very low birth weight infants is affected by mode of feeding: a randomized clinical trial of intermittent versus continuous drip feeding. Pediatr Res.1999; 45 :280A
- Schanler RJ, Shulman RJ, Lau C. Feeding strategies for premature infants: beneficial outcomes of feeding fortified human milk versus preterm formula [comment]. Pediatrics.1999; 103 :1150 –1157[Abstract/Full Text]
- Akintorin SM, Kamat M, Pildes RS, et al. A prospective randomized trial of feeding methods in very low birth weight infants. Pediatrics.1997; 100(4) . Available at: http://www.pediatrics.org/cgi/content/full/100/e4
- Rayyis SF, Ambalavanan N, Wright L, Carlo WA. Randomized trial of slow versus fast feed advancements on the incidence of necrotizing enterocolitis in very low birth weight infants. J Pediatr.1999; 134 :293 –297[Medline]
- Dollberg S, Kuint J, Mazkereth R, Mimouni FB. Feeding tolerance in preterm infants: randomized trial of bolus and continuous feeding. J Am Coll Nutr.2000; 19 :797 –800[Medline]
- Currao WJ, Cox C, Shapiro DL. Diluted formula for beginning the feeding of premature infants. Am J Dis Child.1988; 142 :730 –731[Medline]
- Wang LY, Hung HY, Hsu CH, Kao HA, Huang FY. Clinical experience with early enteral feeding in very-low-birth-weight infants. Chung Hua Min Kuo Hsiao Erh Ko I Hsueh Hui Tsa Chih.1997; 38 :282 –287[Medline]
- Slagle TA, Gross SJ. Effect of early low-volume enteral substrate on subsequent feeding tolerance in very low birth weight infants. J Pediatr.1988; 113 :526 –531[Medline]
- Silvestre MAA, Morbach CA, Brans Y, Shankaran S. A prospective randomized trial comparing continuous versus intermittent feeding methods in very low birth weight neonates. J Pediatr.1996; 128 :748 –752[Medline]
- Dunn L, Hulman S, Weiner J, Kliegman R. Beneficial effects of early hypocaloric enteral feeding on neonatal gastrointestinal function: preliminary report of a randomized trial. J Pediatr.1988; 112 :622 –629[Medline]
- Meetze WH, Valentine C, McGuigan JE, Conlon M, Sacks N, Neu J. Gastrointestinal priming prior to full enteral nutrition in very low birth weight infants. J Pediatr Gastroenterol Nutr.1992; 15 :163 –170[Medline]
- Geraldo V, Pyati S, Joseph T, Pildes RS. Gastric residual (GR): reliability of the measurement. Pediatr Res.1997; 41 :150A
- Lemons JA, Bauer CR, Oh W, et al. Very low birth weight outcomes of the National Institute of Child Health and Human Development Neonatal Research Network, January 1995 through December 1996. Pediatrics.2001; 107 :1 –8[Abstract/Full Text]
PEDIATRICS (ISSN 1098-4275). ©2002 by the American Academy of Pediatrics
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