Iopamidol enema treatment for meconium obstruction of prematurity in extremely low-birth weight infants: a safe and effective method

Ultrasound-guided hydrostatic enema for meconium obstruction in extremely low birth weight infants: a preliminary report

Meconium obstruction (MO) in extremely low birth weight (ELBW) infants is a challenging disease to treat. We performed ultrasound-guided hydrostatic enema on six ELBW infants diagnosed with MO. We consider this procedure to be safe and effective, and recommend it as a treatment for MO in ELBW infants.

Ultrasound-guided contrast enema for meconium obstruction in very low birth weight infants: Factors that affect treatment success

INTRODUCTION

This study aimed to assess the therapeutic results of ultrasound (US)-guided water-soluble contrast enema in very low birth weight (VLBW) preterm infants (<1,500 g) with meconium obstruction and to study factors that affect therapeutic results.

METHODS

This study included a total of 33 consecutive VLBW infants with clinically diagnosed meconium obstruction underwent US-guided water-soluble contrast enema, from April 2007 to March 2014. Patients were classified into two groups based on to procedure outcome: the success group (evacuation of the meconium plug resolution followed by improved bowel distention within 2 days of the procedure, without additional interventions), and the failure group (the contrast enema failed to relieve the obstruction, or other procedure-related complications occurred). Patient- and mother-related clinical factors and procedure-related factors were compared between both groups.

RESULTS

Overall success rate was 54.5%, with 18 successful (M:F=10:8), and 15 failure (M:F=7:8) cases. When compared with the failure group, the success group patients showed statistically significant older gestational age (29(+1) vs. 27 weeks; p=0.028), larger birth weight (1023.1g vs. 790.3g; p=0.048), and higher body weight on the day of the procedure (1036.2g vs. 801.6g, p=0.049). However, no statistically significant differences were seen between other patient and maternal factors. Among the procedure-related factors, retrial of contrast injection during the procedure was associated with significantly higher success than the single trial (p=0.027). The presence of refluxed contrast into the distal ileum was the statistically significant predictor for success of the procedure (p=0.038). There were three cases of bowel perforation (9.1% per person).

CONCLUSION

US-guided water-soluble contrast enema in VLBW infants with meconium obstruction showed a 54.5% success rate and a 9.1% perforation rate per person. Among the procedure-related factors, retrial of contrast injection during the procedure and the presence of refluxed contrast into the distal ileum were related to the success of the procedure.

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.

Therapeutic strategies of meconium obstruction of the small bowel in very-low-birthweight neonates

BACKGROUND

Meconium obstruction without cystic fibrosis in low-birthweight neonates is a distinct clinical entity. We aimed to determine what therapeutic strategies work best in very-low-birthweight neonates with meconium obstruction of the small bowel under varied clinical conditions caused by the associated diseases of prematurity.

METHODS

Medical records of very-low-birthweight neonates with meconium obstruction of the small bowel treated from 1998 to 2008 were retrospectively reviewed. Pre- and postnatal data, treatments, and clinical outcomes were assessed.

RESULTS

Nine patients with perinatal complications were identified. Mean gestational age and birthweight were 26.9 weeks and 863 g, respectively. Abdominal distension developed from 1 to 7 days of life. Five patients were initially treated with Gastrografin enema, three of whom had successful outcomes. Two hemodynamically unstable patients failed to respond to Gastrografin treatment; they ultimately died of sepsis. The remaining four without Gastrografin treatment underwent enterostomy to resolve the obstructions with good results.

CONCLUSIONS

Gastrografin and surgical treatments should be appropriately selected based on the underlying pathologies of meconium obstruction of the small bowel. Therapeutic Gastrografin enema is effective, safe and repeatable; however, it is not recommended for hemodynamically unstable patients. Surgical intervention is reserved for those who develop rapid abdominal distension that risks perforation.