Topiramate Is Safe for Refractory Neonatal Seizures: A Multicenter Retrospective Cohort Study of Necrotizing Enterocolitis Risk

BACKGROUND

A previously published, single-institution, case series suggested an association between topiramate administration in neonates and subsequent development of necrotizing enterocolitis (NEC). This contradicted our more extensive experiences using topiramate in this population. We therefore studied safety and tolerability of topiramate for treating refractory neonatal seizures, hypothesizing that the risk of developing NEC following topiramate exposure was low and that most infants tolerate topiramate.

METHODS

This multicenter retrospective cohort study included seventy-five neonates who received topiramate to treat seizures from January 2011 to October 2019 at three geographically diverse level IV neonatal intensive care units affiliated with pediatric tertiary hospitals. Data included demographics, birth history, seizure etiology, treatment response, side effects, and occurrence and details of NEC.

RESULTS

Three of seventy-five infants (4%) developed NEC following topiramate exposure. These infants did not differ in gestational age, birth weight, seizure etiology, postmenstrual age, weight when topiramate was initiated, or dosing of topiramate. Topiramate was well tolerated. Only three infants (4%) discontinued due to side effects. The most common side effect (20%) was weight loss (typically <5%). Topiramate was felt to be efficacious (61%). Most infants (72%) continued topiramate when discharged.

CONCLUSIONS

Our multicenter, 75-infant study demonstrated that development of NEC after treatment with topiramate was rare (4%) and refutes prior literature suggesting an association. Topiramate was felt to be efficacious and was well tolerated. Although limited by retrospective design, study data are broadly applicable and support thoughtful use of topiramate as a safe, reasonable option for treating refractory neonatal seizures.

Osmolality of Commonly Used Oral Medications in the Neonatal Intensive Care Unit

OBJECTIVE

The administration of hyperosmolar oral products in neonates has been associated with gastrointestinal complications. The American Academy of Pediatrics recommends a maximum osmolality of 450 mOsm/kg for formulas and enteral nutrition for term infants, and recent studies reported intolerance to enteral nutrition with osmolality above 500 mOsm/kg in low birthweight infants. The osmolality of medications administered to neonates is often not available in the literature or from manufacturers. The purpose of this study was to determine the osmolality of oral medications commonly administered to neonates in the NICU.

METHODS

Fifty-two oral medications were chosen for this study, including solutions, suspensions, syrups, elixirs, and intravenous solutions administered orally. The osmolality of each medication was measured in triplicate by using freezing point depression.

RESULTS

Thirty-seven of the 43 medications with measurable values (86.1%) had an osmolality greater than 500 mOsm/kg, and 6 medications (14%) had an osmolality less than 500 mOsm/kg. Nine medications did not result in a value.

CONCLUSIONS

Our study provides osmolality data on oral medications commonly used in neonates with most oral medications having an osmolality greater than 500 mOsm/kg.

The Risk of Necrotizing Enterocolitis following the Administration of Hyperosmolar Enteral Medications to Extremely Preterm Infants

INTRODUCTION

Necrotizing enterocolitis (NEC) is a disease predominantly affecting preterm infants. The administration of hyperosmolar solutions could lead to the development of NEC. The objective of this study was to measure the osmolality of enteral medications used in clinical practice and to assess the risk of NEC following exposure to hyperosmolar medications.

METHODS

A retrospective cohort study in extremely preterm infants (gestational age <28 weeks) born between 2010 and 2016 at a tertiary neonatal intensive care unit in Sweden. 465 infants were identified via the Swedish Neonatal Quality register. Data relating to enteral administrations received during a two-week period were collected from the medical records. The osmolalities of medications were measured using an osmometer. Logistic regression was used to calculate the odds ratio of developing NEC.

RESULTS

A total of 253 patients met the inclusion criteria. The osmolalities of 5 commonly used medications significantly exceeded the recommended limit of 450 mOsm/kg set by the American Academy of Paediatrics (AAP). Most patients (94%) received at least one hyperosmolar medication. No significant risk of developing NEC could be found.

CONCLUSION

The medications used in clinical practice can significantly exceed the limit set by the AAP. This study does not indicate an increased risk of developing NEC in extremely preterm infants following exposure to hyperosmolar medications. Further studies in larger cohorts are needed to determine the specific cut-off level of osmolality in relation to the pathogenesis of NEC.

Effects of Nutrition Supplementation on Osmolality of Expressed Human Milk

BACKGROUND

Provision of human milk to premature infants optimizes outcomes, but it must be supplemented to meet their nutrient and caloric requirements for growth. Our objective was to quantify the osmolality of human milk mixed with commercially available human milk fortifiers (HMF) and powdered infant formula, as currently fed to premature infants, simulating standard neonatal intensive care unit feeding practices for mixing and refrigerator storage.

METHODS

Expressed human milk (EHM) samples obtained from mothers of premature infants (≤32 weeks gestation) were mixed with standard commercial products, and osmolalities were quantified.

RESULTS

HMF significantly increased the micronutrient content and osmolality of EHM. Osmolalities were 291 ± 6 mOsm/kg (mean ± SD) for unsupplemented milk, and 505 ± 5 and 315 ± 19 mOsm/kg after supplementation to 24 kcal/oz using 2 current U.S. Liquid EHM fortifiers. When using powdered infant formulas to further increase the caloric content of fortified EHM >24 kcal/oz, osmolalities increased by 10.5-23.0 mOsm/kg for each additional kcal/oz. The use of powdered formulas alone (without HMF) increased osmolality without comparable increases in nutrient content. Refrigeration for 24 hours did not affect osmolalites.

CONCLUSION

Our finding that several common feeding formulations exceed 450 mOsm/kg, and the lack of evidence of adverse effect, raise the question of whether current maximum osmolality guidelines should be reevaluated to enable optimal nutrition for infants in neonatal intensive care.

Medications That Increase Osmolality and Compromise the Safety of Enteral Feeding in Preterm Infants

BACKGROUND

Medications added to preterm milk feeds have the potential to raise osmolality, causing feed intolerance and necrotizing enterocolitis.

OBJECTIVE

The aim of this study was to evaluate changes in the osmolality of milk feeds and water with 14 medications and the diluent amounts required to keep the osmolality below the safety threshold of ≤450 mOsm/kg. Changes in the osmolality of milk with medications while on continuous infusion over 2 and 4 h were determined.

METHODS

This study was designed to measure the osmolality of 14 commonly used medications in preterm infants both neat and when supplemented with expressed breast milk (EBM), EBM with fortifier (EBMF), preterm formula (PTF), and water. Dose-effect curves were plotted, and the volume of each diluent was calculated to keep the osmolality ≤450 mOsm/kg. Time-effect curves were plotted at 2 and 4 h for each medication for both EBM and EBMF.

RESULTS

Neat osmolality of all except 5 medications were above 2,000 mOsm/kg. The osmolality rose with decreasing proportions of diluents used, depicting an indirect curvilinear relationship between the increasing dilution and osmolality for all except 2 medications. As a diluent, EBM was required in lower dilutions than EBMF. Dilutions needed for additives with PTF were very similar to those of EBM. The change in osmolality over time with additives was statistically significant for EBMF.

CONCLUSIONS

EBM and PTF were found to be safer diluents than EBMF for enteral additives. The practice of keeping milk feeds with medications for continuous feeding is safe for a period of 4 h in EBM.

Target fortification of breast milk with fat, protein, and carbohydrates for preterm infants

OBJECTIVES

Fortification of breast milk is an accepted practice for feeding very low birth weight infants, however, fixed dosage enhancement does not address variations in native breast milk. This could lead to deficiencies in calories and macronutrients. We therefore established the infrastructure for target fortification in breast milk by measuring and adjusting fat, protein, and carbohydrate content daily. We analyzed nutrient intake, growth, and safety variables.

STUDY DESIGN

Each 12-hour batch of breast milk was analyzed using near-infrared spectroscopy. Macronutrients were individually added to routine fortification to achieve final contents for fat (4.4 g), protein (3 g), and carbohydrates (8.8 g) (per 100 mL). Fully breast milk fed healthy very low birth weight infants (<32 weeks) were fed the fortified breast milk for at least 3 weeks. Matched pair analysis of 20 infants fed routinely fortified breast milk was performed using birth weight, gestational age, and postnatal age.

RESULTS

All 650 pooled breast milk samples required at least 1 macronutrient adjusted. On average, 0.3 ± 0.4 g of fat, 0.7 ± 0.2 g of protein, and 1.2 ± 0.2 g of carbohydrate were added. Biochemistry was normal in the 10 target fortified infants (birth weight: 860 ± 309 g, 26.3 ± 1.6 weeks gestational age); weight gain was 19.9 ± 2.7 g/kg/d; and milk intake was 147 ± 5 mL/kg/d (131 ± 16 kcal/kg/d). Osmolality of fortified breast milk was 436 ± 13 mOsmol/kg. Matched pair analysis of infants indicated a higher milk intake (155 ± 5 mL/kg/d) but similar weight gain (19.7 ± 3.3 g/kg/d). No adverse event was observed. The linear relationship between milk intake and weight gain observed in study babies but not seen in matched controls may be related to the variable composition of breast milk.

CONCLUSIONS

Daily target fortification can be safely implemented in clinical routine and may improve growth.

Determining the osmolality of over-concentrated and supplemented infant formulas

BACKGROUND

Hyperosmolar infant feeds can cause osmotic diarrhoea and may be a risk factor for necrotising enterocolitis; the osmolality of infant formula is therefore usually <400 mOsm kg(-1) . However, in fluid-restricted infants and those needing nutritional support, formulas may be over-concentrated or supplemented. The present study aimed to determine the effect of these practices on osmolality.

METHODS

A clinical laboratory osmometer was used to measure the osmolality of infant formulas. The effect of over-concentration and supplementation on osmolality was then determined using three and seven different infant formulas, respectively. Osmolalities were measured in triplicate.

RESULTS

The effect of over-concentration was shown to be linear using Pepti Junior (Cow & Gate, Trowbridge, UK) at concentrations of 12.8% (standard), 17% and 19%. This linear relationship was also demonstrated with Enfamil A.R. (Mead Johnson Nutritionals, Uxbridge, UK) (15%) and Neocate (SHS International Ltd, Liverpool, UK) (21%). The effect of individual additives on osmolality was found to be similar for the seven infant formulas. All preparations of SMA High Energy (SMA Nutrition, Maidenhead, UK) and five of the 12 preparations of Nutriprem 1 (Cow & Gate) exceeded an osmolality of 400 mOsm kg(-1) .

CONCLUSIONS

The effect of over-concentrating infant formulas was shown to be linear, meaning that the osmolality at different concentrations can be predicted accurately. The over-concentrated infant formulas that were measured in the present study did not exceed 400 mOsm kg(-1) , with the exception of 21% Neocate, which would not be used in practice. When supplemented, some infant formulas exceeded an osmolality of 400 mOsm kg(-1) ; this may be relevant in cases of feed intolerance or in those at risk of necrotising enterocolitis.

Strategies to prevent invasive candidal infection in extremely preterm infants

The highest incidence of invasive candidal infection (ICI) occurs in extremely preterm infants (<1000 g birth weight and <or=27 weeks' gestation). In this population, ICI has high mortality, leads to significant neurodevelopmental impairment, and results in increased length of hospital stay and costs. Randomized clinical trials in infants of less than 1000 g birth weight have demonstrated that ICI is decreased 88% by antifungal prophylaxis with fluconazole compared to 54% by nystatin prophylaxis from retrospective studies. Fluconazole is more efficacious than nystatin prophylaxis in infants weighing less than 1000 g, is less expense, requires less frequent dosing (twice weekly intravenous [IV] dosing), and can be given when infants are not feeding. While antifungal prophylaxis is inexpensive, cost-effective, and easy to administer, yet has not been instituted universally despite A-1 evidence from single and multicenter studies demonstrating efficacy and safety. Debate is ongoing over whether empiric therapy or improved infection control practices are superior to prophylaxis, whether prophylaxis should be instituted only in neonatal intensive care units (NICUs) with a relatively high ICI rate, and whether fluconazole prophylaxis is safe or risks emergence of resistance. To date, azole resistance has not emerged with targeted treatment of high-risk infants for the duration of IV catheter use. Empiric therapy for suspected ICI and standardized therapy for candidemia, including central venous catheter removal, may decrease mortality; however, these approaches still risk neurodevelopmental impairment in ICI survivors. Infection control practices have not been subjected to prospective or randomized trials to demonstrate efficacy in reducing fungal infections. Evidence is presented in this article from clinical trials demonstrating efficacy and safety of antifungal prophylaxis in preventing ICI in preterm infants. The greatest impact of antifungal prophylaxis preventing ICI and decreasing Candida-related mortality and neurodevelopmental impairment would be achieved with a universal approach in all NICUs.

Challenging issues in neonatal candidiasis

In an era of quality improvement and 'getting to zero (infections and/or related mortality),' neonatal candidiasis is ripe for evidence-based initiatives. Knowledge of each institution's invasive Candida infection (ICI) incidence and infection-related mortality is critical to evaluate disease burden and effective interventions. Evidenced-based interventions include: antifungal prophylaxis, starting with appropriate dosing, and prompt removal of central venous catheters (CVC). There is A-I evidence supporting antifungal prophylaxis with fluconazole, and it should be considered in every neonatal intensive care unit (NICU). The literature supports targeting infants <1000 g and/or <or=27 weeks, because this group has high infection-related mortality and neurodevelopmental impairment in 57% of survivors. Antifungal prophylaxis has been shown to nearly eliminate infection-related mortality. Interventions start with prenatal initiatives, with women being treated for vaginal candidiasis, especially with preterm labor or complications. Targeting modifiable risk factors, including restriction policies for use of third- and fourth-generation cephalosporins, carbapenems, H2-antagonists, proton pump inhibitors, and postnatal steroids; guidelines for CVC care and removal; and feeding practices, with promotion of early feedings and breast milk, may also reduce risk. A few studies have emerged on empiric antifungal therapy with sepsis evaluations for preterm infants <1500 g and other high-risk patients that have shown favorable effects of eliminating mortality, but these have not been compared to appropriate antifungal therapy and central line removal. Further study of empiric therapy, prospective treatment studies with higher targeted dosing of amphotericin B preparations, fluconazole, and new antifungals with prompt CVC removal may contribute to a 100% survival rate for those infants >1000 g and >or=28 weeks not receiving antifungal prophylaxis. Evaluation of ICI incidence and mortality by gestational age and birth week should be followed in each NICU, to evaluate infection control and prevention.

Re-examination of risk factors for non-Clostridium difficile-associated diarrhoea in hospitalized patients

AIM

This paper is a report of a study to determine the incidence of non-Clostridium difficile-associated diarrhoea in hospitalized patients and to re-evaluate clinical characteristics and other risk factors related to non-C. difficile-associated diarrhoea.

BACKGROUND

Numerous factors are thought to be responsible for diarrhoea in hospitalized patients. Reports about the diarrhoeal effects of some medications administered concomitantly with tube feeding have stimulated reappraisal of the influence of tube feeding as a potential cause.

METHOD

This study was a secondary analysis of data of 154 hospitalized patients collected during a prospective epidemiological study from 1992 to 1993. The secondary analysis was completed in 2006 in order to investigate unanswered questions of current importance.

FINDINGS

The sample was predominantly male and middle aged; approximately 50% were tube fed, and 25% were in an intensive care unit. The incidence of diarrhoea was 35%. Increased severity of illness as well as the combination of sorbitol-containing medication administration and tube feeding were found to be statistically significant factors in the development of diarrhoea.

CONCLUSION

As diarrhoea in hospitalized patients appears to be multifactorial, use of an algorithm to systematically evaluate and manage related factors is recommended.

Growth, efficacy, and safety of feeding an iron-fortified human milk fortifier

OBJECTIVE

Survival rates for preterm infants who weigh between 501 and 1500 g at birth have continued to improve over time. In response to this continuing decrease in birth weight of surviving preterm infants, Enfamil Human Milk Fortifier has recently been reformulated to meet the nutritional requirements of these smaller, more rapidly growing infants. It now provides an increased protein level of 1.1 g/58 kJ, a decreased carbohydrate level of 0.2 g/58 kJ, and a combined linoleic and alpha-linolenic fatty acid content of 157 mg/58 kJ. As these very small preterm infants have an increased requirement for dietary iron, the fortifier has been supplemented with 1.44 mg/58 kJ of iron, an amount of iron similar to that provided in a typical iron-fortified term infant formula. An iron-fortified product obviates the need for administration of an iron supplement, a hyperosmolar-inducing intervention. The purpose of this prospective, double-blind, randomized, controlled study was to evaluate growth, safety, and efficacy in a population of very low birth weight (VLBW) preterm infants who received human milk fortified with either the reformulated iron-fortified powdered human milk fortifier test product (HMF-T) or a powdered commercially available human milk fortifier control product (HMF-C).

METHODS

Infants who weighed < or =1500 g, had a gestational age < or =33 weeks postmenstrual age, and had an enteral intake of at least 100 mL/kg per day of unfortified human milk were stratified by gender and birth weight and randomized to receive HMF-T or HMF-C product from study day 1 to study day 28, hospital discharge, or the termination of human milk feedings, whichever came first. Unless medically indicated, investigators were not to administer iron supplements from study days 1 to 14. Infants were assessed serially for growth; enteral and parenteral intake; serum chemistry and hematologic values; clinical histories, including the administration of blood transfusions; feeding tolerance; respiratory outcomes; and morbidities, including adverse events.

RESULTS

Of the 181 participating infants in this study, 96 received HMF-T and 85 received HMF-C. At randomization, there were no significant differences in infant characteristics between the fortifier groups. The percentage of participants who remained in the study for 28 days was similar between fortifier groups (57% HMF-T, 46% HMF-C). For both fortifier groups, the most frequent reasons for discontinuing the study before study day 28 were unavailability of human milk and hospital discharge. Rate of weight gain was similar between the fortifier groups (17.5 +/- 0.53 g/kg per day for HMF-T and 17.3 +/- 0.59 g/kg per day for HMF-C). Mean achieved weight, length, and head circumference were comparable between groups across the 28-day study period. Total protein intake from enteral and parenteral nutrition was significantly greater for the HMF-T fortifier group; however, this difference did not result in any difference in growth between the 2 fortifier groups. An analysis of the growth and energy intake data of a subset of the intent-to-treat population who adhered more strictly to the study feeding protocol yielded results similar to those seen for the intent-to-treat population. There were no clinically significant differences in the results of laboratory studies between the groups at study days 0, 14, and 28. Anemia of prematurity was prevalent in both study groups; by study day 28, median hematocrit levels were 27.0% (interquartile range [IQR]: 24.0%-29.6%) for the HMF-T group and 26.0% (IQR: 24.0%-31.0%) for the HMF-C group. Median ferritin levels were 77.0 ng/mL (IQR: 37-155 ng/ml) for HMF-T and 92.0 ng/mL (IQR: 33-110 ng/mL) for HMF-C. There were no significant differences between the study fortifier groups in regard to the receipt of medically indicated iron supplements on or before study day 14 or in the administration of blood transfusions before study day 0 or from study days 0 through 14. However, from study day 15 to study day 28, fewer HMF-T infants (n = 12) required a blood transfusion than did HMF-C infants (n = 20). Although the higher levels of iron in the HMF-T fortifier (1.44 mg vs 0.35 mg for HMF-C per 4 packets of powdered fortifier) did not prevent anemia per se, it did reduce the frequency of one of the most serious outcomes of anemia: the need for a blood transfusion. There was no statistically significant difference between fortifier groups in regard to feeding tolerance. Rates of suspected sepsis (26% HMF-T vs 31% HMF-C) and confirmed sepsis (5% HMF-T, 7% HMF-C) were low as were the rates of suspected necrotizing enterocolitis (NEC; 6% HMF-T and 5% HMF-C) and confirmed Bell's stage 2 or more NEC (1% HMF-T and 1% HMF-C). There were no statistically significant differences between the study fortifier groups in regard to the incidence of confirmed and suspected sepsis and NEC.

CONCLUSION

Both human milk fortifiers studied are safe, are well tolerated, and facilitate comparable good growth; however, using the iron-fortified product may reduce the need for blood transfusions in VLBW infants. The similar low rates of suspected and confirmed NEC and sepsis seen in both fortifier groups in this study refutes the premise that the inclusion of iron in fortifiers will increase the incidence of sepsis and NEC. Indeed, the incidence for NEC and sepsis for both groups in this study was lower than is reported for VLBW infants and similar to that seen for infants who are fed human milk.

Enhanced growth of preterm infants fed a new powdered human milk fortifier: A randomized, controlled trial

OBJECTIVE

A prospective, double-blind, randomized, controlled trial was conducted to evaluate the growth and nutritional status of preterm infants receiving preterm human milk supplemented with a newly formulated powdered human milk fortifier (HMF), study fortifier (SF), or a powdered commercial HMF (CF).

METHODS

Infants (n = 144) with a birth weight </=1600 g and gestational age at birth of </=33 weeks were enrolled and randomized before 21 days of life. Study day (SDAY) 1 was defined as the day full-strength fortification (4 packets/100 mL) began and the infant reached an intake of at least 100 mL/kg/day. Growth, biochemical indices of nutritional status, enteral intake, feeding tolerance, clinical histories, and morbidity were assessed serially. The primary outcome variable was weight gain (g/kg/day) from SDAYs 1 to 29 or hospital discharge, whichever came first.

RESULTS

Infants fed human milk supplemented with SF consistently grew more rapidly from SDAYs 1 to 29 (or hospital discharge), regardless of whether the statistical analyses were performed on all subjects who were randomized into the study and reached SDAY 1 (intent-to-treat) or were limited to those able to adhere strictly to the feeding protocol of the study (subgroup). Using mean values adjusted for study site (least square [LS] means), the weight gain differences were 2.6 and 3.8 g/kg/day for the intent-to-treat and subgroup analyses, respectively. Likewise, the length-gain differences were.14 and.18 cm/week for the intent-to-treat and subgroup analyses, respectively. Infants in the SF group reached a weight of 1800 g at SDAY 18, and those in the CF group at SDAY 25. Mean alkaline phosphatase values among infants in the SF group were higher than for the CF infants (eg, LS means: 327 U/L vs 272 U/L, intent-to-treat analysis), likely reflecting the more rapid linear growth of the SF infants. Mean serum calcium values tended to be lower in the SF group in the intent-to-treat analysis and were significantly lower in the subgroup analysis (LS means: 10.3 mg/dL vs 11.2 mg/dL). Both fortifiers were generally well-tolerated, although an increased number of infants in the CF group exited the feeding protocol because of gastric residuals and abdominal distention.

CONCLUSION

A new powdered HMF was shown to enhance the growth of preterm infants, compared with a commercially available powdered HMF in the United States.