Small volume enemas do not accelerate meconium evacuation in very low birth weight infants

Safety of different concentrations of glycerine enema for meconium evacuation in preterm infants: study protocol for a randomised controlled trial

INTRODUCTION

Various approaches are employed to expedite the passage of meconium in preterm infants within the neonatal intensive care unit (NICU), with glycerine enemas being the most frequently used. Due to the potential risk of high osmolality-induced harm to the intestinal mucosa, diluted glycerine enema solutions are commonly used in clinical practice. The challenge lies in the current lack of knowledge regarding the safest and most effective concentration of glycerine enema. This research aims to ascertain the safety of different concentrations of glycerine enema solution in preterm infants.

METHODS AND ANALYSIS

This study protocol is for a single-centre, two-arm, parallel-group, double-blind and non-inferiority randomised controlled trial. Participants will be recruited from a NICU in a teriary class A hospital in China, and eligible infants will be randomly allocated to either the glycerine (mL): saline (mL) group in a 3:7 ratio or the 1:9 ratio group. The enema procedure will adhere to the standardised operational protocols. Primary outcomes encompass necrotising enterocolitis and rectal bleeding, while secondary outcomes encompass feeding parameters, meconium passage outcomes and splanchnic regional oxygen saturation. Analyses will compare the two trial arms based on an intention-to-treat allocation.

ETHICS AND DISSEMINATION

This trial is approved by the ethics committee of the Medical Ethics Committee of West China Second University Hospital of Sichuan University. The results will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2300079199.

The efficacy of glycerin suppositories for preterm infants: A meta-analysis of randomized controlled studies

BACKGROUND

The effect of glycerin suppositories on full enteral feeds remained controversial in preterm infants, and thus we conducted this meta-analysis to identify the influence of glycerin suppositories on full enteral feeds in preterm infants.

METHODS

The protocol was registered in PROSPERO (CRD20214283090). We searched PubMed, EMbase, Web of science, EBSCO and Cochrane library databases through February 2020, and included randomized controlled trials assessing the effect of glycerin suppositories on full enteral feeds in preterm infants. This meta-analysis was performed using the random-effect model.

RESULTS

Six Randomized controlled trials were included in the meta-analysis. Overall, compared with control group in preterm infants, glycerin suppositories demonstrated no significant effect on days to full enteral feeds (mean difference = -0.26; 95% confidence interval [CI] = -1.16 to 0.65; P = .58), the incidence of necrotizing enterocolitis (odd ratio = 3.62; 95% CI = 0.56-23.32; P = .18) or death (odd ratio = 1.46; 95% CI = 0.40-5.40; P = .57), but may increase the days under phototherapy (mean difference = 0.50; 95% CI = 0.43-0.57; P < .00001). Only low heterogeneity was seen among all outcomes.

CONCLUSIONS

Glycerin suppositories may provide no additional benefits to preterm infants.

Management of Prolonged Meconium Evacuation in Preterm Infants - A Survey-based Analysis in German Neonatal Intensive Care Units

AIM

Due to the functional immaturity of bowel motility, a delayed passage frequently requires evacuation of meconium in preterm infants. Often rectal enemas and oral laxatives are used to manage these bowel evacuation disorders.

METHODS

An online survey was sent to all 163 high-level Neonatal Intensive Care Units (NICUs) in Germany. The participants were queried on rectal enemas, laxative therapy, and outcome incidences.

RESULTS

A total of 110/163 (67.5%) hospitals participated in the study. 103/110 (93.6%) participating sites applied rectal enemas in cases of delayed meconium evacuation and 63/110 (57.3%) additionally used oral laxatives. In total, 15 different solutions and 7 different application systems were used for rectal instillation. Preterm infants receiving enemas within the first 48 hours after birth were found to have a significantly lower incidence of FIP (p = 0.006). Altogether 8 different oral laxatives were utilized.

CONCLUSION

Therapeutic approaches to the management of prolongated meconium evacuation differ widely among German NICUs. Our survey highlights the diversity of applied substances, means of application, and differences in duration and frequency of interventions. Macrogol was commonly used in neonates as an oral laxative despite the lack of approval from the manufacturer.

Interventions for Promoting Meconium Passage in Very Preterm Infants—A Survey of Current Practice at Tertiary Neonatal Centers in Germany

Meconium passage is often delayed in preterm infants. Faster meconium passage appears to shorten the time to full enteral feeds, while severely delayed meconium passage may indicate meconium obstruction. Neonatologists often intervene to promote meconium passage, assuming that benefits outweigh potential risks such as necrotizing enterocolitis (NEC). We performed an anonymous online survey on different approaches to facilitate meconium passage among tertiary neonatal intensive care units (NICUs) in Germany between February 2022 and April 2022. We collected information on enteral nutrition, gastrointestinal complications, and interventions to promote meconium passage. We received 102 completed questionnaires (response rate 64.6%). All responders used interventions to promote meconium passage, including enemas (92.0%), orally applied contrast agents (61.8%), polyethylene glycol (PEG) (46.1%), acetylcysteine (19.6%), glycerin suppositories (11.0%), and maltodextrin (8.8%). There was substantial heterogeneity among NICUs regarding frequency, composition, and mode of administration. We found no differences in NEC incidence between users and nonusers of glycerin enemas, high or low osmolar contrast agents, or PEG. There is wide variability in interventions used to promote meconium passage in German NICUs, with little or no evidence for their efficacy and safety. Within this study design, we could not identify an increased risk of NEC with any intervention reported.

Lipid enemas for meconium evacuation in preterm infants - a retrospective cohort study

Background

Enemas are used in preterm infants to promote meconium evacuation, but frequent high-volume enemas might contribute to focal intestinal perforation (FIP). To replace a regime consisting of frequent enemas of varying volume and composition, we implemented a once-daily, low-volume lipid enema (LE) regimen. We investigated its impact on meconium evacuation, enteral nutrition, and gastrointestinal complications in preterm infants.

Methods

We performed a single-center retrospective study comparing cohorts of preterm infants < 28 weeks gestation or < 32 weeks, but with birth weight < 10th percentile, before and after implementing LE. Outcomes were rates of FIP, necrotizing enterocolitis (NEC), and sepsis. We assessed stooling patterns, early enteral and parenteral nutrition. We used descriptive statistics for group comparisons and logistic regression to identify associations between LE and gastrointestinal complications and to adjust for group imbalances and potential confounders. Exclusion criteria were gastrointestinal malformations or pre-determined palliative care.

Results

Data from 399 infants were analyzed, 203 before vs. 190 after implementing LE; in the latter period, 55 protocol deviations occurred where infants received no enema, resulting in 3 groups with either variable enemas, LE or no enema use. Rates of FIP and sepsis were 11.9% vs. 6.4% vs. 0.0% and 18.4% vs. 13.5% vs. 14.0%, respectively. NEC rates were 3.0% vs. 7.8% vs. 3.5%. Adjusted for confounders, LE had no effect on FIP risk (aOR 1.1; 95%CI 0.5–2.8; p = 0.80), but was associated with an increased risk of NEC (aOR 2.9; 95%CI 1.0–8.6; p = 0.048). While fewer enemas were applied in the LE group resulting in a prolonged meconium passage, no changes in early enteral and parenteral nutrition were observed. We identified indomethacin administration and formula feeding as additional risk factors for FIP and NEC, respectively (aOR 3.5; 95%CI 1.5–8.3; p < 0.01 and aOR 3.4; 95%CI 1.2–9.3; p = 0.02).

Conclusion

Implementing LE had no clinically significant impact on meconium evacuation, early enteral or parenteral nutrition. FIP and sepsis rates remained unaffected. Other changes in clinical practice, like a reduced use of indomethacin, possibly affected FIP rates in our cohorts. The association between LE and NEC found here argues against further adoption of this practice.

Trial registration

Registered at the German Register of Clinical Trials (no. DRKS00024021; Feb 022021).

Glycerin suppositories used prophylactically in premature infants (supp): A pilot randomized controlled trial

BACKGROUND

Glycerin suppositories are often used to facilitate meconium evacuation in premature infants. The evidence for this practice is inconclusive. The purpose of this study was to assess the feasibility of a multicenter randomized controlled trial on the effectiveness of this treatment strategy.

STUDY DESIGN

We conducted an external pilot study for a multicenter randomized controlled trial of premature infants randomized to glycerin suppositories or placebo procedure. Participants were included if they were gestational age of 24 weeks 0 days to 31 weeks 6 days and/or birthweight of 500 to 1500 grams. We excluded infants with life-threatening congenital anomalies, contraindications to receiving suppositories, or signs of clinical instability. Outcomes included cost, recruitment, and treatment-related adverse events.

RESULT

A total of 109 were screened, 79 were initially eligible, and 34 consented to participate. Four of these infants were excluded prior to randomization due to thrombocytopenia, 30 were randomized, and 26 reached full enteral feeds. Three infants (10%) experienced rectal bleeding 5 to 43 days after completing study treatments. An anal fissure was noted in two of these patients. There were no cases of rectal perforation but one infant assigned to active treatment developed necrotizing enterocolitis.

CONCLUSIONS

Conducting a multicenter randomized controlled trial on the use of glycerin suppositories in premature infants is feasible. Minor modifications to the study protocol are needed to increase participant recruitment and simplify the administration of study treatments.

Prevention of meconium obstruction in very low birth weight preterm infants

INTRODUCTION

Delayed meconium expulsion is a cause of bowel obstruction in the extremely premature newborn (<28 WGE) weighing less than 1500g at birth.

OBJECTIVE

To evaluate the efficacy of conservative treatment in the prevention of meconium obstruction in very-low-birt- weight preterm infants.

METHOD

Descriptive and retrospective study performed at the Neonatal Intensive Care Unit of a tertiary level hospital. All very-low-birth-weight preterm infants who were born during the study period, from August 2016 to January 2017, and who had meconium obstruction were included.

RESULTS

A sample of 42 newborn infants was obtained. Regarding the expulsion of meconium, 57.1% of the sample spontaneously ejected meconium, while 42.9% received different treatments. Of these, 72.2% were treated with saline enemas, 16% with acetylcysteine enemas, 16% with Gastrografin^® and none required surgical treatment.

CONCLUSION

Conservative treatment seems to be an effective therapeutic measure for the prevention of meconium obstruction in very-low-birth-weight preterm infants since it achieved the expulsion of meconium without having to apply surgical treatment.

A Randomized Controlled Trial of Glycerin Suppositories During Phototherapy in Premature Neonates

OBJECTIVE

To determine if glycerin suppositories were effective in reducing total duration of phototherapy in premature neonates. We hypothesized that glycerin suppositories would have no effect on phototherapy duration or total serum bilirubin levels.

DESIGN

Prospective randomized controlled double-blinded trial.

SETTING

Level IV NICU.

PARTICIPANTS

Neonates born between 30 weeks, 0 days and 34 weeks, 6 days gestational age who developed physiologic hyperbilirubinemia needing phototherapy.

METHODS

Neonates were randomized to the no-suppository group or to the suppository group. Neonates were randomized to receive glycerin suppositories every 8 hours while under phototherapy or to a sham group. The primary outcome was total hours of phototherapy. Secondary outcomes included peak total serum bilirubin levels, time from start to discontinuation of phototherapy, rate of decline in bilirubin levels, repeat episodes of phototherapy, and number of stools while the neonates received phototherapy.

RESULTS

A total of 39 neonates were assigned to the no-suppository group and 40 to the suppository group. Withholding suppositories was not inferior to providing suppositories. The total hours of phototherapy were not longer (i.e., noninferior) among neonates not provided suppositories (61 ± 53 hours) than among those given suppositories (72 ± 49 hours). There were no differences in peak bilirubin levels, rate of bilirubin decline, or repeat episodes of phototherapy.

CONCLUSION

Routine use of glycerin suppositories among preterm neonates who receive phototherapy does not affect bilirubin levels or phototherapy duration.

Enemas, suppositories and rectal stimulation are not effective in accelerating enteral feeding or meconium evacuation in low-birthweight infants: a systematic review

Early full enteral feeding in preterm infants decreases morbidity and mortality. Our systematic review covered the effectiveness of rectal stimulation, suppositories and enemas on stooling patterns and feeding tolerance in low-birthweight infants born at up to 32 weeks. It comprised seven studies published between 2007 and 2014 and covered 495 infants.

CONCLUSION

Suppositories were ineffective in shortening the time to reach full enteral feeding, and the evidence on enemas was contradictory. Enemas and rectal stimulation did not shorten the time until complete meconium evacuation was reached. Further research into safe, effective interventions to accelerate meconium excretion is needed.

Meconium Evacuation for Facilitating Feed Tolerance in Preterm Neonates: A Systematic Review and Meta-Analysis

BACKGROUND

A delayed passage of meconium is considered as a risk factor for feed intolerance in preterm neonates.

OBJECTIVES

The aim of this study was to review the effects of different therapeutic agents for meconium evacuation on feed tolerance in preterm neonates.

METHODS

A systematic review of randomised controlled trials (RCTs) of different therapeutic agents for meconium evacuation in preterm neonates (gestation <32 weeks and/or birth weight <1,500 g) using the Cochrane systematic review methodology was undertaken. Databases including Google Scholar were searched in January 2016. The primary outcome was the time to reach full feeds (TFF; ≥120 ml/kg feeds with stoppage of parenteral nutrition >24 h). Secondary outcomes included necrotising enterocolitis (NEC), weight at discharge and adverse effects. The results were summarised as per the GRADE guidelines.

RESULTS

Six RCTs (2 each of glycerine suppository and enema, 1 normal saline enema and 1 oral osmotic contrast agent; n = 442) with a low or unclear risk of bias were included. The pooled estimate (random effects model) showed no reduction in TFF [mean difference (MD) -0.03, 95% CI -2.47, 2.41, p = 0.98; level of evidence: low]. No differences in NEC [risk ratio (RR) 1.71, 95% CI 0.63, 4.65, p = 0.30; level of evidence: low] and weight at discharge (MD -0.08, 95% CI -0.30, 0.15, p = 0.50; level of evidence: low) were found. The trial assessing oral osmotic contrast agents reported a trend towards a higher incidence of NEC ≥ stage II. There were no other adverse effects.

CONCLUSION

Limited low-quality evidence indicates that prophylactic glycerine suppository, small volume glycerine/normal saline enema or oral osmotic contrast agents to evacuate meconium did not reduce TFF in preterm neonates. Large, well-designed trials are essential to study this clinically significant issue.

Glycerin laxatives for prevention or treatment of feeding intolerance in very low birth weight infants

BACKGROUND

Feeding intolerance is a common clinical problem among preterm infants. It may be an early sign of necrotising enterocolitis, sepsis or other serious gastrointestinal conditions, or it may result from gut immaturity with delayed passage of meconium. Glycerin laxatives stimulate passage of meconium by acting as an osmotic dehydrating agent and increasing osmotic pressure in the gut; they stimulate rectal contraction, potentially reducing the incidence of feeding intolerance.

OBJECTIVES

To assess the effectiveness and safety of glycerin laxatives (enemas/suppositories) for prevention or treatment of feeding intolerance in very low birth weight (VLBW) infants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 4), MEDLINE, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). We restricted our search to all randomised controlled trials and applied no language restrictions. We searched the references of identified studies and reviews on this topic and handsearched for additional articles. We searched the database maintained by the US National Institutes of Health (www.clinicaltrials.gov) and European trial registries to identify ongoing trials.

SELECTION CRITERIA

We considered only randomised or quasi-randomised controlled trials that enrolled preterm infants < 32 weeks' gestational age (GA) and/or < 1500 g birth weight. We included trials if they administered glycerin laxatives and measured at least one prespecified clinical outcome.

DATA COLLECTION AND ANALYSIS

We used standard methods of The Cochrane Collaboration and its Neonatal Group to assess methodological quality of trials, to collect data and to perform analyses.

MAIN RESULTS

We identified three trials that evaluated use of prophylactic glycerin laxatives in preterm infants. We identified no trials that evaluated therapeutic use of glycerin laxatives for feeding intolerance. Our review showed that prophylactic administration of glycerin laxatives did not reduce the time required to achieve full enteral feeds and did not influence secondary outcomes, including duration of hospital stay, mortality and weight at discharge. Prophylactic administration of glycerin laxatives resulted in failure of fewer infants to pass stool over the first 48 hours. Included trials reported no adverse events.

AUTHORS' CONCLUSIONS

Our review of available evidence for glycerin laxatives does not support the routine use of prophylactic glycerin laxatives in clinical practice. Additional studies are needed to confirm or refute the effectiveness and safety of glycerin laxatives for prevention or treatment of feeding intolerance in VLBW infants.

Glycerin suppositories used prophylactically in premature infants (SUPP) trial: a study protocol for a pilot randomized controlled trial

BACKGROUND

Feeding is a significant challenge for premature infants in the neonatal intensive care unit (NICU). These patients are often treated with glycerin suppositories to stimulate the passage of meconium and prevent feeding intolerance. Unfortunately, the evidence for this practice is inconclusive.

METHODS/DESIGN

This protocol is for an external pilot study that will assess the feasibility of a superiority, placebo-controlled, parallel-design, multicenter randomized controlled trial. Participants are premature infants treated in a level 3 NICU with a gestational age 24 to 32 weeks and/or birth weight of 500 to 1500 g. Thirty participants will be recruited as part of this external pilot study. Participants will be randomized to glycerin suppository (250 mg) or placebo starting 48 to 72 h after birth and continuing once daily until meconium evacuation is complete or for a maximum of 12 days. The placebo consists of a 250-mg glycerin suppository placed in the diaper rather than the rectum. Study treatments are administered by the charge nurse on duty who is not otherwise involved in patient care. All other clinicians and research personnel will remain blinded. Outcomes for the pilot study are percentage of eligible participants randomized, percentage of infants reaching full enteral feeds, cost, and treatment-related adverse events (rectal bleeding, rectal perforation, and anal fissure).

DISCUSSION

This external pilot study will assess the feasibility of a multicenter randomized controlled trial of glycerin suppositories in premature infants. The subsequent multicenter trial will have sufficient power to determine whether this treatment strategy is associated with decreased time to full enteral feeds.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02153606.

Glycerin enemas and suppositories in premature infants: a meta-analysis

BACKGROUND AND OBJECTIVE

Premature infants are often given glycerin enemas or suppositories to facilitate meconium evacuation and transition to enteral feeding. The purpose of this study was to assess the available evidence for this treatment strategy.

METHODS

We conducted a systematic search of Medline, Embase, Central, and trial registries for randomized controlled trials of premature infants treated with glycerin enemas or suppositories. Data were extracted in duplicate and meta-analyzed using a random effects model.

RESULTS

We identified 185 premature infants treated prophylactically with glycerin enemas in one trial (n = 81) and suppositories in two other trials (n = 104). All infants were less than 32 weeks gestation and had no congenital malformations. Treatment was associated with earlier initiation of stooling in one trial (2 vs 4 days, P = .02) and a trend towards earlier meconium evacuation in another (6.5 vs 9 days, P = .11). Meta-analysis demonstrated no effect on transition to enteral feeding (0.7 days faster, P = .43) or mortality (P = 0.50). There were no reports of rectal bleeding or perforation but there was a trend towards increased risk of necrotizing enterocolitis with glycerin enemas or suppositories (risk ratio = 2.72, P = .13). These three trials are underpowered and affected by one or more major methodological issues. As a result, the quality of evidence is low to very low. Three other trials are underway.

CONCLUSIONS

The evidence for the use glycerin enemas or suppositories in premature infants in inconclusive. Meta-analyzed data suggest that treatment may be associated with increased risk of necrotizing enterocolitis. Careful monitoring of ongoing trials is required.

Does visceral osteopathic treatment accelerate meconium passage in very low birth weight infants?- A prospective randomized controlled trial

BACKGROUND

To determine whether the complementary approach of visceral manipulative osteopathic treatment accelerates complete meconium excretion and improves feeding tolerance in very low birth weight infants.

METHODS

This study was a prospective, randomized, controlled trial in premature infants with a birth weight <1500 g and a gestational age <32 weeks who received a visceral osteopathic treatment 3 times during their first week of life or no treatment.

RESULTS

Passage of the last meconium occurred after a median of 7.5 days (95% confidence interval: 6-9 days, n = 21) in the intervention group and after 6 days (95% confidence interval: 5-9 days, n = 20,) in the control group (p = 0.11). However, osteopathic treatment was associated with a 8 day longer time to full enteral feedings (p = 0.02), and a 34 day longer hospital stay (Median = 66 vs. 100 days i.e.; p=0.14). Osteopathic treatment was tolerated well and no adverse events were observed.

CONCLUSIONS

Visceral osteopathic treatment of the abdomen did not accelerate meconium excretion in VLBW (very low birth weight)-infants. However infants in the osteopathic group had a longer time to full enteral feedings and a longer hospital stay, which could represent adverse effects. Based on our trial results, we cannot recommend visceral osteopathic techniques in VLBW-infants.

TRIAL REGISTRATION

Clinical trials.gov: NCT02140710.

Randomized controlled trial of prophylactic rectal stimulation and enemas on stooling patterns in extremely low birth weight infants

OBJECTIVE

We hypothesized that rectal stimulation and small volume enemas would accelerate normalization of stooling patterns in extremely low birth weight infants.

STUDY DESIGN

In a randomized controlled trial, infants with a gestational age 28 weeks received one of the following: twice daily rectal stimulation and/or enemas until two stools were passed daily, without enemas or stimulation, for three consecutive days. Intervention only occurred when symptoms, abdominal distension and no defecation, occurred in the previous 24 h. Enema administration occurred if abdominal distension persisted without defecation occurring after rectal stimulation. Multivariable linear regression was used to determine the contribution of a patent ductus arteriosus (PDA) on normalization of stooling patterns and feeding tolerance.

RESULT

Rectal stimulation and/or small volume enemas did not accelerate the median (quartile range) time normalization of stooling patterns, 13 (11-20) days in control group and 16 (12-25.5) days in intervention group. A higher frequency of PDA occurred in the intervention than the non-intervention group. Infants with a persistent PDA had a longer duration of parenteral nutrition, worse feeding tolerance and more days to achieve normal stooling patterns. In multivariable regression analysis, a PDA, not repeated rectal stimulation and/or enemas, was significantly related to stooling and feeding tolerance.

CONCLUSION

Twice daily administration of rectal stimulation and/or enemas did not normalize stooling patterns (fecal frequency). A PDA is an important determinant of acquisition of normal stooling patterns and feeding tolerance of very immature newborns.

Feeding intolerance in the preterm infant

Feeding intolerance (FI), defined as the inability to digest enteral feedings associated to increased gastric residuals, abdominal distension and/or emesis, is frequently encountered in the very preterm infant and often leads to a disruption of the feeding plan. In most cases FI represents a benign condition related to the immaturity of gastrointestinal function, however its presentation may largely overlap with that of an impending necrotizing enterocolitis. As a consequence, individual interpretation of signs of FI represents one of the most uncontrollable variables in the early nutritional management of these infants, and may lead to suboptimal nutrition, delayed attainment of full enteral feeding and prolonged intravenous nutrition supply. Strategies aimed at preventing and/or treating FI are diverse, although very few have been validated in large RCT and systematic reviews. The purpose of this paper is to summarize the existing information on this topic, spanning from patho-physiological and clinical aspects to the prevention and treatment strategies tested in clinical studies, with specific attention to practical issues.

The effect of an osmotic contrast agent on complete meconium evacuation in preterm infants

OBJECTIVE

To determine whether enteral application of the osmotic contrast agent Gastrografin accelerates complete meconium excretion and improves feeding tolerance in very low birth weight infants.

METHODS

This study was a stratified, randomized, placebo-controlled trial in premature infants with a birth weight <1500 g and a gestational age <32 weeks who received 3 mL/kg Gastrografin diluted 1:3 with water within their first 24 hours of life, or placebo.

RESULTS

Passage of last meconium occurred after a median of 7 days (95% confidence interval: 6-9 days, n = 39) in the intervention group and after 8 days (95% confidence interval: 7-10 days, n = 39) in the control group (P = .61); however, Gastrografin application was associated with a 7.5-day shorter time to full enteral feedings, a 24-day shorter stay in the NICU, and a 17-day reduction in the overall hospital stay in the intervention group compared with the control group. A numerically higher incidence of necrotizing enterocolitis (21%) was observed in the intervention group, however.

CONCLUSIONS

Gastrografin application did not accelerate meconium evacuation, but the higher stool frequency during the first week of life had a beneficial effect on the time to full enteral feedings and later hospital stay; however, it may increase the necrotizing enterocolitis risk. Further investigations are needed with modified protocols, and the prophylactic use of Gastrografin cannot currently be recommended without further clinical trials.

Butyrate enemas enhance both cholinergic and nitrergic phenotype of myenteric neurons and neuromuscular transmission in newborn rat colon

Postnatal changes in the enteric nervous system (ENS) are involved in the establishment of colonic motility. In adult rats, butyrate induced neuroplastic changes in the ENS, leading to enhanced colonic motility. Whether butyrate can induce similar changes during the postnatal period remains unknown. Enemas (Na-butyrate) were performed daily in rat pups between postnatal day (PND) 7 and PND 17. Effects of butyrate were evaluated on morphological and histological parameters in the distal colon at PND 21. The neurochemical phenotype of colonic submucosal and myenteric neurons was analyzed using antibodies against Hu, choline acetyltransferase (ChAT), and neuronal nitric oxide synthase (nNOS). Colonic motility and neuromuscular transmission was assessed in vivo and ex vivo. Butyrate (2.5 mM) enemas had no impact on pup growth and histological parameters compared with control. Butyrate did not modify the number of Hu-immunoreactive (IR) neurons per ganglia. A significant increase in the proportion (per Hu-IR neurons) of nNOS-IR myenteric and submucosal neurons and ChAT-IR myenteric neurons was observed in the distal colon after butyrate enemas compared with control. In addition, butyrate induced a significant increase in both nitrergic and cholinergic components of the neuromuscular transmission compared with control. Finally, butyrate increased distal colonic transit time compared with control. We concluded that butyrate enemas induced neuroplastic changes in myenteric and submucosal neurons, leading to changes in gastrointestinal functions. Our results support exploration of butyrate as potential therapy for motility disorders in preterm infants with delayed maturation of the ENS.

Meconium obstruction in absence of cystic fibrosis in low birth weight infants: an emerging challenge from increasing survival

Background

Meconium abnormalities are characterized by a wide spectrum of severity, from the meconium plug syndrome to the complicated meconium ileus associated with cystic fibrosis. Meconium Related Ileus in absence of Cystic Fibrosis includes a combination of highly viscid meconium and poor intestinal motility, low grade obstruction, benign systemic and abdominal examination, distended loops without air fluid levels. Associated risk factors are severe prematurity and low birth weight, Caesarean delivery, Maternal MgSO4 therapy, maternal diabetes. In the last 20 yrs a new specific type of these meconium related obstructions has been described in premature neonates with low birth weight. Its incidence has shown to increase while its management continues to be challenging and controversial for the risk of complicated obstruction and perforation.

Materials and methods

Among 55 newborns admitted between 1992-2008 with Meconium Related Ileus as final diagnosis, data about Low Birth Weight infants (LBW < 1500 g) were extracted and compared to those of patients ≥ 1500 g. Hischsprung's Diseases and Cystic Fibrosis were excluded by rectal biopsy and genetic probe before discharge. A softening enema with Gastrografin was the first option whenever overt perforation was not present. Temporary stoma or trans appendiceal bowel irrigation were elected after unsuccessful enema while prompt surgical exploration was performed in perforated cases. NEC was excluded in all operated cases. Data collected were perinatal history and neonatal clinical data, radiological signs, clinical course and complications, management and outcome.

Results

30 cases with BW ≥ 1500 g had an M/F ratio16/14, Mean B.W. 3052 g, Mean G.A. 37 w Caesarean section rate 40%. There were 10 meconium plug syndrome, 4 small left colon syndromes, and 16 meconium ileus without Cystic Fibrosis. Five cases were born at our institution (inborn) versus 25 referred after a mean of 2, 4 Days (1-7) after birth in another Hospital (outborn). They were managed, after a Gastrografin enema with 90% success rate, by 1 temporary Ileostomy and 2 trans appendiceal irrigation. 25 cases with BW< 1500 g (LBW) had M/F ratio 11/14, Mean B.W. 818 g, Mean G.A. 27 w, Caesarean section rate 70%, assisted ventilation 16/25. There were 8 inborn and 17 outborn. Gastrografin enema was successful in 6 out 8 inborn infants only, all referred within one week from birth. There were 12 perforations mainly among late referred LBW outborn.

Conclusions

Meconium Related Ileus without Cystic Fibrosis responds to conservative management and softening enema in most of mature infants. In LBW clinical course is initially benign but as any long standing bowel obstruction management may present particular challenges. Clinical and plain radiographic criteria are reliable for making diagnosis and testing for Cystic Fibrosis may not be indicated. Enema may be resolutive when performed in a proper environment. Perforated cases may be confused with NEC which is excluded by clinical history, no signs of sepsis, lab signs missing, abdominal signs missing, typical radiological signs missing. The higher complication rate is recorded among cases delivered and initially managed in Neonatal Units without co-located Surgical Facilities. Early diagnosis and aggressive medical therapy may lead to higher success rate and help avoiding surgical interventions. Surgical therapy in uncomplicated cases, unresponsive to medical management, should be minimally aggressive.

Randomized controlled trial: impact of glycerin suppositories on time to full feeds in preterm infants

BACKGROUND

Feed intolerance delays achievement of enteral feeding in preterm infants. Parenteral nutrition is associated with cholestasis and increased risk of sepsis. Glycerin suppositories have been used to promote gastrointestinal motility and feed tolerance.

OBJECTIVES

To investigate whether daily glycerin suppositories (a) reduce the time to full enteral feeding in infants born at <32 weeks' gestation, and (b) influence feed tolerance, incidence of sepsis or necrotizing enterocolitis, duration of oxygen requirement, growth or age at discharge.

METHODS

Design - prospective open randomized controlled trial; study population - preterm infants stratified into 2 subgroups, 24-27(+6) weeks (24-27 weeks + 6 days) and 28-31(+6) weeks; intervention - daily glycerin suppository for 10 days from 24 h of age, 250 mg (24-27(+6) weeks subgroup) or 500 mg (two 250-mg suppositories; 28-31(+6) weeks subgroup); controls - no intervention. The same feeding protocol and departmental guidelines for other aspects of neonatal intensive care were used in all subjects. Analysis was by intention to treat.

RESULTS

54 babies were recruited (31 males), 29 randomized to receive suppositories; 48 achieved full enteral feeds. The median (range) time to full feeds was 1.6 days shorter in intervention group babies than controls, but not statistically significant: 7.4 (4.6-30.9) days versus 9.0 (4.4-13.3) days (p = 0.780; 95% confidence interval: -1.917, 2.166). No significant differences were observed in secondary outcomes. Intervention group babies passed their first stool earlier than controls (median: day 2 vs. day 4; p = 0.016).

CONCLUSION

Regular glycerin suppositories did not reduce the time to full enteral feeds in infants born at <32 weeks' gestation in our setting.

Postnatal changes in enteric plexus axonal thickness

PURPOSE

Chronological age has not always been an accurate predictor of gut motility in newborns. We hypothesized that the enteric plexus is immature at birth. We studied whole-mount preparations of the myenteric plexus in pigs from mid-point of gestation to adulthood.

METHODS

Distal large bowel whole-mount preparations of the myenteric plexus were stained using ACHE histochemistry in five pigs from six different age groups (60 and 90 days gestation, newborn, 4 and 12 weeks old, and adult pigs). With the aid of light micrographs and Image J program the axonal diameter, distance between ganglia, neuronal size and neuronal nucleus size were measured. Statistical significance was measured using one-way ANOVA test.

RESULTS

There was significant increase in axonal diameter and interganglionic distance, with increasing age in the myenteric plexus of rectum in pigs (P < 0.05). Neuronal cell size and nucleus size of the enteric neurons also increased with age, but was not statistically significant.

CONCLUSION

This study shows for the first time that the axonal thickness in the enteric myenteric plexus undergoes striking changes during the first 12 weeks of life in piglets. Assessment of axonal thickness in rectal biopsies may be a valuable morphological feature in diagnosing functional intestinal obstruction in infants.

A case of fetal midgut volvulus and jejunal atresia: nutritional support and maintenance of mucosal function and integrity

Fetal midgut volvulus is a quite rare disease. Here, we report a case of a preterm newborn with fetal peritonitis, jejunal atresia with volvulus of post-atresic small bowel since about 30 cm from ileo-cecal valve (ICV) followed by a not-used microileus and microcolon. The surgical intervention consisted in the resection of volvulated necrotic small bowel followed by primary anastomosis. After surgery, total parenteral nutrition (TPN) has been started since 16(th) of post-operative days when enteral feeding (EN) was administered with a lactose-free formula containing hydrolyzed protein and medium-chain triglycerides (Pregestimil). Re-establishing intestinal continuity was preferred rather than stoma that would have required TPN. In fact, re-operation could have led to a shorter residual small bowel (RSB), since the anastomosis was at 15 cm from ICV. Our study provides evidence that not only the type of procedure (enteral versus parenteral) of nutritional support, but also the type of milk may modify the outcome. Early EN should be encouraged in newborn abdominal surgical patients because it is associated with reduced complications.