Biomarker-based text messages to promote lactation success in mothers of critically Ill infants: a randomized controlled pilot study

OBJECTIVE

Infrequent breast pumping limits mother's own milk production in mothers of infants admitted to the neonatal intensive care unit. We aimed to determine the feasibility and benefit of biomarker-based personalized text messages on pumping frequency and milk sodium levels. A secondary aim examined lactation outcomes.

STUDY DESIGN

In this randomized controlled pilot study, 51 mothers were randomized to receive personalized text messages regarding pumping frequency or standard care.

RESULTS

There were no differences in pumped milk volume or sodium level, however, there was a trend towards the intervention group pumping more frequently, which was significant on day 5 (p = 0.035), and they lactated nearly 9 days longer. Post-hoc analysis found the intervention group tended to be more likely to pump ≥ 500 mL by day14 (p = 0.08), a marker of long-term lactation success.

CONCLUSION

Personalized biomarker-based text messages are feasible and may support lactation in mothers of critically ill infants.

Effect of Routine Gastric Residual Aspiration on the Preterm Infant Fecal Microbiome

OBJECTIVE

 Enteral feeding tubes are used in neonatal intensive care units (NICUs) to assess feeding tolerance by utilizing preprandial gastric residual aspiration. This study evaluates the effect of gastric residual aspiration on the preterm infant fecal microbiome and gastrointestinal inflammation.

STUDY DESIGN

 Fifty-one very low birth weight (VLBW) infants (≤32 weeks' gestational age and ≤1,250 g) enrolled in a larger single-center randomized controlled trial evaluating the effects of routine and nonroutine gastric residual aspiration were selected for further analysis. Of those infants, 30 had microbiome analysis performed on stools collected at 6 weeks by sequencing the bacterial V1 to V3 variable regions of the genes encoding for 16S rRNA. In an additional 21 infants, stool samples collected at 3 and 6 weeks were analyzed for intestinal inflammation using a cytokine multiplex panel.

RESULTS

 Microbial communities between groups were not distinct from each other and there was no difference in intestinal inflammation between groups. Analyses using gene expression packages DESeq2 and edgeR produced statistically significant differences in several taxa, possibly indicating a more commensal intestinal microbiome in infants not undergoing gastric residual aspiration.

CONCLUSION

 Omission of routine gastric residual aspiration was not associated with intestinal dysbiosis or inflammation, providing additional evidence that monitors preprandial gastric residuals is unnecessary.

KEY POINTS

· Omission of routine gastric residual aspiration was not associated with intestinal dysbiosis or inflammation.. · Existing literature indicates preprandial gastric aspiration does not reliably correlate with development of necrotizing enterocolitis but does correlate with delayed enteral nutrition.. · Further study is required but this data that suggest monitoring preprandial gastric residuals are unnecessary..

Mother's Own Milk Versus Donor Human Milk: What's the Difference?

Mother's own milk (MOM) is known to decrease complications in preterm infants and when unavailable, it is recommended that preterm very low-birth weight infants be fed donor human milk (DHM). Due to the pasteurization, processing, and lactation stage of donors, DHM does not contain the same nutritional, immunologic, and microbial components as MOM. This review summarizes the differences between MOM and DHM, the potential effects on health outcomes, and the clinical implications of these differences. Finally, implications for research and clinical practice are discussed.

Milk Biomarkers of Secretory Activation in Breast Pump-Dependent Mothers of Preterm Infants: An Integrative Review

Background: Lack of mother's own milk (MOM) at discharge from the neonatal intensive care unit (NICU) is a global problem and is often attributable to inadequate MOM volume. Evidence suggests that the origins of this problem are during the first 14 days postpartum, a time period that includes secretory activation (SA; lactogenesis II, milk coming in). Objectives: To describe and summarize evidence regarding use of MOM biomarkers (MBMs) as a measure of SA in pump-dependent mothers of preterm infants in the NICU and to identify knowledge gaps requiring further investigation. Methods: An integrative review was conducted using Whittemore and Knafl methodology incorporating the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. A search using electronic databases MEDLINE (through PubMed) and CINAHL (Cumulative Index to Nursing and Allied Health Literature) and reference lists of included articles was conducted. Results: Of the 40 articles retrieved, 6 met the criteria for inclusion. Results revealed the following five findings: (1) Achievement of SA defined by MBMs is delayed and/or impaired in mothers of preterm infants. (2) MBMs are associated with pumped MOM volume. (3) Achievement of SA defined by MBMs is associated with pumping frequency. (4) Delayed and/or impaired achievement of SA defined by MBMs may be exacerbated by maternal comorbidities. (5) There is a lack of consensus as to which MBM(s) and analysis techniques should be used in research and practice. Conclusions: MBMs hold tremendous potential to document and monitor achievement of SA in mothers of preterm infants, with multiple implications for research and clinical practice.

A Scoping Review of the Oral Microbiome in Preterm Infants

The purpose of this scoping review was to examine the oral microbiome composition in preterm infants, sampling and collection methods, as well as exposures associated with oral microbiome composition and health implications. We conducted a scoping review of the literature using the Arskey and O'Malley framework. We identified a total of 13 articles which met our inclusion criteria and purpose of this scoping review. Articles included in this review compared the oral microbiome in preterm infants to term infants, examined alterations to the oral microbiome over time, compared the oral microbiome to different body site microbiomes, and explored associations with clinically relevant covariates and outcomes. Exposures associated with the diversity and composition of the oral microbiome in preterm infants included delivery mode, oral feeding, oropharyngeal care, skin-to-skin care, and antibiotics. Day of life and birth weight were also associated with oral microbiome composition. The oral microbiome may be associated with the composition of the tracheal and gut microbiomes, likely due to their proximity. Alpha and beta diversity findings varied across studies as well as the relative abundance of taxa. This is likely due to the different sampling techniques and timing of collection, as well as the wide range of infant clinical characteristics. Multiple factors may influence the composition of the oral microbiome in preterm infants. However, given the heterogeneity of sampling techniques and results within this review, the evidence is not conclusive on the development as well as short- and long-term implications of the oral microbiome in preterm infants and needs to be explored in future research studies. KEY POINTS: · Day of life is a critical factor in oral microbiome development in preterm infants.. · The oral microbiome may be associated with tracheal and gut microbiome colonization.. · Future research should examine sampling methodology for examining the oral microbiome.. · Future research should explore associations with the oral microbiome and adverse health outcomes..

Untargeted Metabolomic Analysis of Lactation-Stage-Matched Human and Bovine Milk Samples at 2 Weeks Postnatal

Epidemiological data demonstrate that bovine whole milk is often substituted for human milk during the first 12 months of life and may be associated with adverse infant outcomes. The objective of this study is to interrogate the human and bovine milk metabolome at 2 weeks of life to identify unique metabolites that may impact infant health outcomes. Human milk (n = 10) was collected at 2 weeks postpartum from normal-weight mothers (pre-pregnant BMI < 25 kg/m2) that vaginally delivered term infants and were exclusively breastfeeding their infant for at least 2 months. Similarly, bovine milk (n = 10) was collected 2 weeks postpartum from normal-weight primiparous Holstein dairy cows. Untargeted data were acquired on all milk samples using high-resolution liquid chromatography-high-resolution tandem mass spectrometry (HR LC-MS/MS). MS data pre-processing from feature calling to metabolite annotation was performed using MS-DIAL and MS-FLO. Our results revealed that more than 80% of the milk metabolome is shared between human and bovine milk samples during early lactation. Unbiased analysis of identified metabolites revealed that nearly 80% of milk metabolites may contribute to microbial metabolism and microbe-host interactions. Collectively, these results highlight untargeted metabolomics as a potential strategy to identify unique and shared metabolites in bovine and human milk that may relate to and impact infant health outcomes.

Sociodemographic Factors and Intestinal Microbiome Development in Preterm, Very Low Birth Weight Infants

OBJECTIVE

 Preterm very low birth weight (VLBW) infants are at risk for intestinal morbidities and dysbiotic development of the intestinal microbiome. Despite the influence of sociodemographic factors on premature infant health outcomes, whether they shape the intestinal microbiome early in life is not clear. The objective was to explore the associations between race, sex, and socioeconomic status and the intestinal microbiome of VLBW infants during the first 4 weeks of life.

STUDY DESIGN

 This was a secondary analysis of data from an ongoing randomized trial of 79 infants ≤30 weeks' gestation and ≤1,500 g. Stool samples were collected at week 1 through week 4, frozen to -80°C and analyzed by 16S rRNA sequencing of the V4 region using Illumina MiSeq. Reads were analyzed to measure α and β diversity as well as relative abundance of bacteria in the intestinal microbiome.

RESULTS

 Of the 79 infants, 63 had at least one sample available. Twenty-three (37%) of infants were African American, 30 (48%) were male, and 44 (71%) had Medicaid insurance. There were no statistically significant (<0.05) differences in α diversity or β diversity, and the differential abundance analysis suggests limited patterns of distinction in the intestinal microbiome between non-African American and African American infants, male and female infants, and infants with maternal private or Medicaid insurance.

CONCLUSION

 Our results suggest race, sex, and socioeconomic status shape colonization of specific microorganisms to a limited extent. Future studies should confirm these findings and determine clinical relevance through further study of differentially abundant microorganisms and additional factors contributing to colonization patterns.

KEY POINTS

· Diversity of the gut microbiome was similar between infants of varying race, sex, and socioeconomic status.. · We observed sociodemographic-linked differences in colonization of individual taxa.. · Further study is required to confirm these results and the clinical relevance of these findings..

Oral Care in Critically Ill Infants and the Potential Effect on Infant Health: An Integrative Review

BACKGROUND

Critically ill infants admitted to the neonatal intensive care unit are at risk for ventilator-associated pneumonia and abnormal oral colonization. Adherence to evidence-based guidelines for oral care in critically ill adults is associated with improved short- and long-term health outcomes. However, oral care guidelines for critically ill infants admitted to the neonatal intensive care unit have not been established, possibly increasing their risk of ventilator-associated pneumonia and other health complications.

OBJECTIVE

To describe and summarize the evidence regarding oral care for critically ill infants admitted to the neonatal intensive care unit and to identify gaps needing further investigation.

METHODS

The MEDLINE (through PubMed) and CINAHL databases were searched for observational studies and randomized controlled trials investigating the effect of oral care on oral colonization, ventilator-associated pneumonia, and health outcomes of infants in the neonatal intensive care unit.

RESULTS

This review of 5 studies yielded evidence that oral care may promote a more commensal oral and endotracheal tube aspirate microbiome. It may also reduce the risk of ventilator-associated pneumonia and length of stay in the neonatal intensive care unit. However, the paucity of research regarding oral care in this population and differences in oral care procedures, elements used, and timing greatly limit any possible conclusions.

CONCLUSIONS

Oral care in critically ill infants may be especially important because of their suppressed immunity and physiological immaturity. Further appropriately powered studies that control for potential covariates, monitor for adverse events, and use recommended definitions of ventilator-associated pneumonia are needed to make clinical recommendations.

Pasteurization of human milk affects the miRNA cargo of EVs decreasing its immunomodulatory activity

In this report, we evaluated the effect of the pasteurization (P) process of mother's own milk (MOM) on the miRNA content of extracellular vesicles (EVs) and its impact on innate immune responses. Differences in size or particle number were not observed upon pasteurization of MOM (PMOM). However, significant differences were observed in the EV membrane marker CD63 and miRNA profiles. miRNA sequencing identified 33 differentially enriched miRNAs between MOM_EV and PMOM_EV. These changes correlated with significant decreases in the ability of PMOM_EV to modulate IL-8 secretion in intestinal Caco2 cells where only MOM_EV were able to decrease IL-8 secretion in presence of TNFα. While EVs from MOM_EV and PMOM_EV were both able to induce a tolerogenic M2-like phenotype in THP-1 macrophages, a significant decrease in the transcript levels of IL-10 and RNA sensing genes was observed with PMOM_EV. Together, our data indicates that pasteurization of MOM impacts the integrity and functionality of MOM_EV, decreasing its EVs-mediated immunomodulatory activity. This data provides biomarkers that may be utilized during the optimization of milk processing to preserve its bioactivity.

Plastics in the global environment assessed through material flow analysis, degradation and environmental transportation

Knowledge on environmental plastic emission and spatial and temporal accumulation is vital for the development of successful mitigation strategies and risk assessments of plastics. In this study, emissions of both micro and macro plastic from the plastic value chain to the environment were assessed on a global level through a mass flow analysis (MFA). All countries, 10 sectors, 8 polymers and 7 environmental compartments (terrestrial, freshwater or oceanic) are distinguished in the model. The results assess a loss of 0.8 million tonnes (mt) of microplastics and 8.7 mt of macroplastics to the global environment in 2017. This is respectively 0.2 % and 2.1 % of plastics produced in the same year. The packaging sector contributed most for macroplastic emissions, and tyre wear for microplastic emissions. With the MFA results, accumulation, degradation and environmental transportation are considered in the Accumulation and dispersion model (ADM) until 2050. This model predicts macro- and microplastic accumulation in the environment to 2.2 gigatonnes (Gt) and 3.1 Gt in 2050 respectively (scenario: yearly consumption increase of 4 %). This will be 30 % less when a yearly production reduction of 1 % until 2050 is modeled to 1.5 and 2.3 Gt macro and microplastics respectively. Almost 2.15 Gt of micro and macroplastics accumulate in the environment until 2050 with zero plastic production after 2022 due to leakage from landfills and degradation processes. Results are compared to other modeling studies quantifying plastic emissions to the environment. The current study predicts lower emissions to ocean and higher emissions to surface waters like lakes and rivers. Non aquatic, terrestrial compartments are observed to accumulate most plastics emitted to the environment. The approach used results in a flexible and adaptable model that addresses plastic emissions to the environment over time and space, with detail on country level and environmental compartments.

Leveraging mHealth and a milk expression frequency biomarker during postpartum to prolong lactation among parents of critically ill infants: a pilot study

OBJECTIVE

To assess the feasibility and potential benefits of personalized biomarker-based text messages in prolonging lactation among parents of critically ill infants.

STUDY DESIGN

Thirty-six participants were randomized to receive either daily texts with Mother's Own Milk (MOM) sodium levels or standard care. Surveys at months 1 and 3 assessed whether infants were receiving exclusive MOM feeding, any MOM feeding, and whether the parent was still lactating. Kaplan-Meier and log-rank tests were used for time-to-event analysis within and between intervention and control groups.

RESULTS

Participants were predominantly on Medicaid (72%), delivered infants <1500 g, and by c-section (56%). Kaplan-Meier probabilities at month 3 suggest prolonged MOM feeding (63% [0.95CI, 0.43-0.91] vs. 41% [0.95CI, 0.21-0.67]) and lactation (63% [0.95CI, 0.42-0.95] vs. 37% [0.95CI, 0.18-0.76]) in the enhanced group compared to the control group.

CONCLUSION

Personalized biomarker-based text messages are feasible and may prolong lactation and MOM feeding among parents of critically ill infants.

Content validity of a Safe Nursing Care Checklist for a neonatal unit

BACKGROUND

Nursing checklists have been shown to improve communication, reduce the occurrence of adverse events, and promote safe, quality care in different care settings. However, to date, there is no validated patient care safety checklist for nurses caring for infants in Neonatal Intensive Care Units (NICU).

AIM

To describe development and content validation of the "Safe Nursing Care Checklist for Infants Hospitalized in the Neonatal Intensive Care Unit".

STUDY DESIGN

Online Survey.

METHODS

Based upon an integrative literature review, we developed a checklist focused on safe nursing care for infants in the NICU. Nursing experts participated in three rounds of a content validation process where they rated the items online. An agreement level ≥0.90 was required for inclusion in the checklist. Forty- three expert nurses with experience working in the NICU and who were certified in neonatal nursing or had a master's or doctoratal degree in child health provided content validation of the patient care checklist.

RESULTS

The final checklist contained 45 items with content validation index scores greater than 90%. The instrument was structured into six dimensions including patient identification, effective communication, medication safety, infection prevention, fall prevention, and pressure injuries/skin injuries prevention.

CONCLUSION

Content validity was established for the "Safe Nursing Care Checklist for Infants Hospitalized in the Neonatal Intensive Care Unit" which can identify strengths and weaknesses in safe nursing care for infants in the NICU as well as direct educational interventions to promote nursing care based on scientific evidence.

RELEVANCE TO CLINICAL PRACTICE

This checklist can potentially be used by bedside nurses to promote provision of safe care to infants in the NICU and to guide corrective strategies and encourage evidence-based decision-making. Validation in the clinical setting is needed.

Nonpharmacologic Factors Affecting Milk Production in Pump-Dependent Mothers of Critically Ill Infants: State of the Science

BACKGROUND

Improved health outcomes for critically ill infants including neurodevelopmental, immunological, and cost benefits are dependent upon the dose and duration of mother's own milk feedings. However, mothers of infants admitted to the neonatal intensive care unit (NICU) must express their milk (pump-dependent) and often struggle with milk production.

PURPOSE

To examine the state of the science on nonpharmacologic modifiable expression factors that may influence milk production in pump-dependent mothers of critically ill infants admitted to the NICU.

DATA SOURCES

PubMed, Embase, and CINAHL databases from 2005 to 2020.

SEARCH STRATEGY

Guided by the lactation conceptual model, the authors searched for peer-reviewed studies with terms related to milk volume, pump dependency, critically ill infants, and modifiable factors, which may influence milk volume and assessed 46 eligible studies.

DATA EXTRACTION

Data were extracted by 3 reviewers with a systematic staged review approach.

RESULTS

Evidence from 26 articles found expressed milk volume may be influenced by multiple potentially modifiable factors. Simultaneous expression with a hospital-grade electric pump at least 5 times per day beginning 3 to 6 hours after delivery, and adding complementary techniques including hand expression, hands-on-pumping, music, breast massage, warm compresses, skin-to-skin care, and the mother expressing near her infant may promote increased milk volume.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Healthcare providers should assist pump-dependent mothers with early initiation and frequent milk removal with a hospital-grade breast pump. Further research is needed to explore optimal frequency of expressions, dose and timing of skin-to-skin care, and other targeted strategies to improve expressed milk volume.

Influence of Sociodemographic and Occupational Factors on Safety Culture in Neonatal Intensive Care in Brazil

BACKGROUND

Patient safety culture is influenced by factors such as professional category, experience, and age. Understanding these factors can inform initiatives to improve safety.

PURPOSE

To evaluate the relationship between sociodemographic and occupational characteristics on health professionals' perception of patient safety culture.

METHODS

A cross-sectional study involving 514 health care professionals from Brazilian neonatal intensive care units was conducted using the Hospital Survey on Patient Safety Culture.

RESULTS

Several sociodemographic and occupational characteristics were associated with higher perceptions of safety culture, including older age and having a higher level of education.

CONCLUSION

Sociodemographic and occupational factors may influence the safety culture in neonatal intensive care units and should be considered when developing and implementing strategies to improve safety.

Antepartum Breast Pump Education for Mothers and Their Support Person: Effect on Time to First Expression and Lactation Outcomes-A Randomized Controlled Pilot Study

Objective: To determine the effect of providing antenatal education regarding milk expression to the support person (SP) of mothers of preterm infants on time to initial milk expression following delivery and daily volume of expressed mother's own milk. Methods: Sixty-one mothers delivering infants <35 weeks gestation and their SP were randomized to receive antenatal education regarding milk expression or to receive standard care. Time to initiation of milk expression was determined through self-report and verified through the electronic medical records. Expressed milk volume was measured on days 1-7 and weekly for 3 weeks. Results: No difference in time to first expression or expressed milk volume was found between groups. Posthoc analysis suggests those in the antenatal education group were more likely to express without nursing assistance and expressed more frequently during days 1-5. Conclusions: SP antenatal education may be an important step in supporting lactation in mothers of critically ill infants. Further research is needed to determine whether SP education during both the antenatal and early postpartum periods could improve lactation success. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT04006509.

Neonatal Feeding Tube Colonization and the Potential Effect on Infant Health: A Review

Background

Infants in the neonatal intensive care unit (NICU) often require feeding tubes (FT) for weeks to months. Because FTs are in near constant contact with human milk and/or formula, rapid and extensive bacterial growth is possible. Due to their immature immunologic and gastrointestinal (GI) systems, infants may be at significant health risk due to FT colonization. In adults, length of time FTs remain in place (dwell time) affects the degree of colonization and biofilm formation which is important in infants whose tubes remain in place up to 30 days.

Objective

The purpose of this review was to describe and summarize the evidence regarding FT bacterial colonization in infants and identify gaps needing further investigation.

Methods

Medline, CINAHL, and Embase databases were searched for clinical and/or laboratory-based observational and randomized controlled studies investigating the presence of bacteria in neonatal FTs.

Results

This review of 10 studies found evidence that neonatal FTs may contain high quantities of potentially pathogenic and antibiotic resistant bacteria and longer dwell times may increase the bacterial load. Furthermore, evidence suggests FT colonization may be nosocomial in origin and contribute to adverse infant health. Feeding tubes are an unrecognized source of bacterial colonization which may increase morbidity in premature infants and thus the presence of bacteria in FTs is an important area of investigation in the nutritional care of vulnerable infants in the NICU.

Implications

Further appropriately powered studies which are clinically based, use appropriate analyses, and control for potential covariates are necessary to make clinical recommendations.

Exploring Social and Demographic Factors as Determinants of Intestinal Inflammation in Very Low Birth-Weight Infants

BACKGROUND

Very low birth-weight (VLBW) infants are disproportionately affected by inflammatory morbidities including necrotizing enterocolitis. Despite the influence of social and demographic factors on infant health outcomes, their relationship with intestinal inflammation is unknown.

PURPOSE

To explore the influence of maternal race, maternal socioeconomic status, and infant sex on intestinal inflammation in VLBW infants.

METHODS

This was a secondary analysis of existing data from a randomized controlled trial of 143 infants 32 weeks' gestation or less and weighing 1250 g or less. In the previous study, fecal calprotectin and S100A12 values were collected at weeks 3 and 6. The infant sample was determined on the basis of the availability of these results, which served as intestinal inflammation biomarkers for the present study. General linear mixed models assessed the relationship between biomarkers and social and demographic factors. Gestational age, antibiotic exposure, mother's own milk feeding, acuity, and week of sample collection were used as control variables.

FINDINGS/RESULTS

The sample included 124 infants. Fifty-two infants (42%) were African American, 86 (69%) had Medicaid coverage, and 65 (53%) were male. Fecal calprotectin levels were higher in African American infants (P = .02) and infants with private insurance coverage (P = .009); no difference was found between sexes. There was no association between S100A12 levels and infant sex, maternal race, or socioeconomic status.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Consideration of social and demographic factors may be important when caring for VLBW infants. Further exploration of factors contributing to associations between social or demographic factors and intestinal inflammation is needed.

Effect of Postpartum Depo Medroxyprogesterone Acetate on Lactation in Mothers of Very Low-Birth-Weight Infants

Objective: This study examined the effect of postpartum administration of depo medroxyprogesterone acetate (DMPA) on milk production, time to onset of secretory activation, lactation duration, and infant consumption of mother's own milk (MOM) in mothers of preterm very low-birth-weight (VLBW) infants. Materials and Methods: We conducted a secondary analysis of data from mothers who delivered infants weighing ≤1,500 g and at ≤32 weeks' gestation. The volume of milk produced was measured on days 1-7, 14, and 21 by weighing all expressed milk on an electronic scale. Time to secretory activation was determined through self-report of a feeling of breast fullness. Information on lactation duration and the percent of feeds consisting of MOM consumed by infants was obtained from the medical records. Results: Mothers who received postpartum DMPA were more likely to be African American (72.4% versus 31.4%; p = 0.0006), unemployed (65.5% versus 44.5%; p = 0.027), and Medicaid eligible (89.7% versus 67.2%; p = 0.019). There were no differences in daily milk production between mothers who received DMPA before hospital discharge (n = 29) compared with those who did not (n = 141). When mothers who reached secretory activation before receiving DMPA were removed from analysis, receiving DMPA was associated with a later onset of secretory activation (103.7 versus 88.6 hours; p = 0.028). There were no statistically significant differences between the study groups in lactation duration or infant MOM consumption. Conclusions: DMPA, when administered postpartum to mothers of preterm VLBW infants, delayed secretory activation, but had no detrimental effect on milk production or lactation duration. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT01892085.

Indicators of Secretory Activation in Mothers of Preterm Very Low Birth Weight Infants

BACKGROUND

Inconsistent information exists regarding indicators of secretory activation in mothers delivering very low birth weight infants.

RESEARCH AIMS

To compare time to the onset of secretory activation using three separate indicators. A secondary aim examined the association between indicators of secretory activation and milk production.

METHODS

Indicators of secretory activation included maternal perception, volume attainment (production of ≥ 20 mL in two consecutive expression sessions) and biomarkers (sodium and lactose) obtained at volume attainment. Milk production was measured on Days 1-7 and then weekly for 6 weeks.

RESULTS

In 69 mothers of infants born ≤ 32 weeks' gestation and < 1500 g, we found no correlation in time to secretory activation between indicators. Earlier volume attainment was associated with increased milk production on Days 1-7, 14, 21, and 28 (all p < .007). Participants who exhibited both normal lactose and sodium levels produced more milk on Days 28 and 42 (p = .028 and .011), those with only normal lactose levels produced more on Day 42 (p = .026) and those with only normal sodium levels on Day 28 (p = .036). Earlier secretory activation by volume attainment was associated with increased expression frequency during Days 2-5 (all p < .014) and participants with normal biomarkers expressed more frequently during Days 2-5 (all p < .020).

CONCLUSION

Mothers of very low birth weight infants are at risk for delayed secretory activation, which may decrease their milk production. Frequent expression during the first 5 days postpartum may promote earlier secretory activation. Valid methods of determining secretory activation are necessary to develop interventions promoting earlier secretory activation.

Demographic, Social, and Personal Factors Associated With Lactation Cessation by 6 Weeks in Mothers of Very Low Birth Weight Infants

BACKGROUND

Although mother's own milk decreases prematurity-associated morbidities, mothers of infants born preterm and very low birth weight experience a significantly shorter lactation duration. Little is known regarding factors associated with lactation cessation during the hospitalization of a very low birth weight infant.

RESEARCH AIM

To determine demographic, social, and personal factors associated with lactation cessation by 6-weeks postpartum in mothers delivering very low birth weight infants.

METHODS

We used a retrospective, longitudinal, two-group comparison design using data from a randomized control study. Mothers of very low birth weight infants (N = 142) were enrolled from a labor and delivery unit associated with a Level 4 neonatal intensive care unit. Demographic, social, and health information was obtained from the medical records. Participants were surveyed regarding lactation goals, experience, and reason(s) for cessation.

RESULTS

Participants who did not continue lactating for more than 6 weeks were more likely to be unemployed (p = .019), Medicaid eligible (p = .009), less educated (p < .031), smoke (p = .002), provide less skin-to-skin care (p = .007), and to delay the decision to provide their milk to their infant (p = .007). After Bonferroni adjustment, only minutes of skin-to-skin care remained statistically significant. Insufficient maternal milk production was the most common reason for lactation cessation.

CONCLUSION

While the etiology of lactation cessation is often non-modifiable, strategies aimed at maintaining mother's own milk production, smoking cessation, increasing skin-to-skin care, and promoting an earlier decision to lactate, may prolong lactation duration in this vulnerable population.This RCT was registered (2012-00071) with ClinicalTrials.com on 6/28/2013.

A Qualitative Study of Pregnant Women's Perspectives on Antibiotic Use for Mom and Child: Implications for Developing Tailored Health Education Interventions

The overutilization of antibiotics during pregnancy and early life are associated with adverse health outcomes for mothers and infants. In this study, we explored pregnant women’s opinions and concerns of antibiotics and how perceptions may affect their health-related decision-making. We conducted 18 in-depth, semi-structured interviews with pregnant women and used the Health Belief Model (HBM) as a framework to analyze the data. We found that mothers generally understood the benefits of antibiotics and were aware that antibiotics are clinically effective for treating bacterial infections. Importantly, perceived barriers related to antibiotic use included concerns regarding the impact of antibiotics on breastfeeding efficacy, microbial health, and societal factors such as antimicrobial resistance. The prescription of antibiotics by a healthcare provider was a cue to action for women, as they trusted providers to recommend medications that were safe for them and their infants. Overall, mothers shared that receiving education on the effects of antibiotics would improve their self-efficacy and decision-making surrounding the use of antibiotics for treating illness. Implications for tailored perinatal health education interventions to enhance antibiotic use, knowledge, and decision-making are discussed.

Timing of milk expression following delivery in mothers delivering preterm very low birth weight infants: a randomized trial

OBJECTIVE

To determine the effect of timing of expression initiation on mother's own milk production and time to secretory activation in mothers of preterm infants.

STUDY DESIGN

180 mothers delivering infants ≤1500 grams and ≤32 weeks gestation were randomized to begin expression within 60 (early), 61-180 (intermediate) or 181-360 (late) minutes following delivery. Milk volume was measured on days 1-7 and weekly for 6 weeks. Time to secretory activation was determined through self-report.

RESULTS

The late group produced more milk than the early group in the first 3 days (p = 0.015-0.031) and over 6 weeks (p = 0.045). The late group had more expressions on day 1 (early: p = 0.049; intermediate; p = 0.048).

CONCLUSION

Initiation of expression at 181-360 min following delivery was associated with increased milk production for 6 weeks following delivery. Further research is needed to determine the effect of expression frequency on milk production in the first days following birth.

Effect of Aspiration and Evaluation of Gastric Residuals on Intestinal Inflammation, Bleeding, and Gastrointestinal Peptide Level

OBJECTIVE

To determine the effect of gastric residual aspiration and evaluation on preterm very low birth weight infants' gastrointestinal function, intestinal inflammation, and gastrointestinal mucosal bleeding.

STUDY DESIGN

This single-center, randomized trial compared omission of gastric residuals vs prefeed gastric residuals in 143 infants ≤32 weeks of gestation with a birthweight of ≤1250 g for 6 weeks after birth. Serum levels of gastrin and motilin were collected between 14 and 21 days of life. Stools were collected at 3 and 6 weeks of age and analyzed for calprotectin and S100A12 levels. All stools were tested for occult blood for 6 weeks.

RESULTS

Means for gastrin (P = .999) and motilin (P = .694) were similar between groups and there were no statistically significant differences in adjusted means for transformed calprotectin (P = .580), and S100A12 (P = .212). Both calprotectin (P = .003) and S100A12 (P = .002) increased from week 3 to week 6. The mean percentage of stools positive for occult blood (P = .888) were similar between the groups.

CONCLUSIONS

Gastrointestinal function, intestinal inflammation, and gastrointestinal mucosal bleeding were similar whether aspiration and evaluation of gastric residuals were eliminated or not, suggesting routinely evaluating gastric residuals before every feeding may be unnecessary. TRIAL REGISTRATION CLINICALTRIALS.GOV:: NCT01863043.

Determinants of the Very Low-Birth-Weight Infant's Intestinal Microbiome: A Systematic Review

The intestinal microbiome is the genetic material from microorganisms residing in the intestinal tract. Very low-birth-weight infants (VLBW; birth weight ≤1500 g) are a physiologically compromised population undergoing a unique period of initial intestinal microbiome establishment. Evidence supports a connection between the intestinal microbiome and gastrointestinal illness that disproportionately affects VLBW infants. Necrotizing enterocolitis, an inflammatory and often necrotic condition of the intestine, and late-onset sepsis, a bloodstream infection occurring after 3 days of life, are thought to be associated with delayed or abnormal intestinal microbiome development. Here, we review the determinants, or factors, that influence the VLBW infant's intestinal microbiome and discuss clinical implications. PubMed, Web of Science, EMBASE, and CINAHL were systematically searched for publications addressing factors with the potential to affect the intestinal microbiome of VLBW infants. Results indicate that infant's age and weight, mode of delivery, antibiotic exposure, medication use, feeding regime, environment, and perinatal-/infant-associated factors may be important determinants of the microbiome in this vulnerable population. Clinicians have opportunities to support positive development of the VLBW infant's intestinal microbiome through antibiotic stewardship, support of human milk feeding, and hygienic care practices.

Consumption of Mother's Own Milk by Infants Born Extremely Preterm Following Implementation of a Donor Human Milk Program: A Retrospective Cohort Study

OBJECTIVE

To compare mothers' own milk (MOM) consumption by infants born extremely preterm before and after implementation of a donor human milk (DHM) program and determine healthcare provider's knowledge and practices regarding DHM.

STUDY DESIGN

One hundred fifty-seven infants born at <30 weeks of gestation were enrolled during 3 time-periods. Group 1: before DHM program implementation, Group 2: the year following implementation, and Group 3: the second year after implementation. The proportion of feeds consisting of MOM for 6 weeks following birth was analyzed using a generalized linear mixed model. The study's second phase surveyed healthcare providers regarding knowledge and practices concerning DHM.

RESULTS

Group 1 consumed feeds with a greater proportion of MOM than Group 3 during weeks 1 (P < .001) and 3 (P = .007) and more than both Group 2 (P = .033) and 3 (P = .021) in week 4. During the first 14 days, Group 1 consumed feeds with 23.6% more MOM than Group 3 (P = .002) and had a greater odds of consuming feeds with > 90% MOM (P < .001) than Group 3. During days 1-28, Group 1 consumed feeds with 22% more MOM than Group 3 (P = .003) and had greater odds of consuming feeds with >90% MOM than Group 2 (P = .020) and 3 (P = .004). Knowledge regarding DHM was inconsistent among providers and they were unlikely to communicate potential risks and benefits of DHM to mothers.

CONCLUSIONS

Following implementation of a DHM program, MOM consumption decreased over 2 years. Strategies focused on lactation success are necessary to increase MOM consumption.

Effect of Gastric Residual Evaluation on Enteral Intake in Extremely Preterm Infants: A Randomized Clinical Trial

IMPORTANCE

Evaluating prefeed gastric residuals is considered routine care but has little supporting evidence.

OBJECTIVE

To determine the effect of omitting prefeed gastric residual evaluation on nutritional outcomes in extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

This single-center randomized clinical trial compared the omission of gastric residual evaluation with prefeed gastric residual evaluation. Infants were recruited from a level 4 neonatal intensive care unit and were enrolled from October 17, 2013, to October 8, 2016, and then followed up for 6 weeks after birth. Eligible participants were infants born at 32 or fewer weeks' gestation with a birth weight of 1250 g or less; they were enrolled within 72 hours after birth and within 24 hours after feeding initiation. All participants (N = 143) were included in the modified intent-to-treat analysis, which was conducted from March to July 2018.

INTERVENTIONS

The residual group underwent prefeed gastric residual evaluation; the no residual group did not. Feeding decisions were made according to nutritional guidelines, and infants received only human milk.

MAIN OUTCOMES AND MEASURES

The primary outcome was weekly enteral nutrition intake in mL/kg for 6 weeks after birth.

RESULTS

Of 143 infants, 74 (51.7%) were randomized to undergo gastric residual evaluation (residual group) and 69 (48.3%) to omitted gastric residual evaluation (no residual group). The residual group comprised an even number of male and female infants (37 [50.0%]) with a mean (SD) gestational age of 27.1 (2.4) weeks and a mean (SD) birth weight of 888.8 (206.6) grams, whereas the no residual group had more male infants (36 [52.17%]), a mean (SD) gestational age of 27 (1.2) weeks, and a mean (SD) birth weight of 915.2 (180) grams. The no residual group had feedings that advanced more quickly compared with the residual group (mean weekly increase, 20.7 mL/kg/d vs 17.9 mL/kg/d; P = .02) and consumed more feedings at weeks 5 (137.2 [95% CI, 128.6-145.8]; P = .03) and 6 (141.6 [95% CI, 133.2-150.0]; P = .03). Among the secondary outcomes, the no residual group had higher mean estimated log weights (7.01 [95% CI, 6.99-7.02] vs 6.98 [95% CI, 6.97-7.00]; P = .03), had fewer episodes of abdominal distention (0.59 [95% CI, 0.34-1.01] vs 1.79 [95% CI, 1.27-2.53]; P = .001), and were discharged 8 days earlier (4.21 [95% CI, 4.14-4.28] vs 4.28 [95% CI, 4.19-4.36]; P = .01). Odds for necrotizing enterocolitis (0.058 [95% CI, 0.018-0.190] vs 0.026 [95% CI, 0.006-0.109]), death (0.004 [95% CI, 0.0003-0.046] vs 0.012 [95% CI, 0.001-0.131]), late-onset sepsis (0.970 [95% CI, 0.67-1.40] vs 1.38 [95% CI, 0.97-1.94]), and ventilator-associated pneumonia (0.084 [95% CI, 0.033-0.214] vs 0.056 [95% CI, 0.019-0.168]) were similar between groups.

CONCLUSIONS AND RELEVANCE

Among extremely preterm infants, the omission of gastric residual evaluation increased the delivery of enteral nutrition as well as improved weight gain and led to earlier hospital discharge; these results may translate into evidence-based practice.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01863043.

Comparison of Neonatal Nursing Practices for Determining Feeding Tube Insertion Length and Verifying Gastric Placement With Current Best Evidence

BACKGROUND

Oral-nasogastric feeding tubes (FTs) are often malpositioned, placing infants at risk for complications. Confusion exists regarding the accuracy of methods to determine FT insertion length and verify gastric FT placement, and it is unknown whether evidence-based methods are used by neonatal nurses.

PURPOSE

To compare individual and unit-based neonatal nursing practices regarding methods used to determine FT insertion length and verify gastric FT placement.

METHODS

Neonatal nurses were surveyed about individual and unit-based practices regarding methods used to determine FT insertion length and verify gastric FT placement in infants in the neonatal intensive care unit.

RESULTS

Sixty neonatal nurses completed the survey, with 63% utilizing the nose-ear-midway to the umbilicus method, which was included in 50% of protocols and is associated with up to a 90% accuracy rate. Although it has an unacceptably high inaccuracy rate, the nose-to-ear-to-xiphoid method was used by 32% of nurses and recommended in 30% of protocols. To verify gastric FT placement, 98% of nurses used auscultation of a whoosh sound and 83% used aspiration of gastric contents. Neither verification method is supported by evidence or recommended for use.

IMPLICATIONS FOR PRACTICE

A lack of consistency exists between nursing practice and evidence-based methods.

IMPLICATIONS FOR RESEARCH

Research is needed to determine more accurate and reliable ways to determine FT insertion depth and verify gastric FT placement in neonates.

Personalization of the Microbiota of Donor Human Milk with Mother's Own Milk

The American Academy of Pediatrics recommends that extremely preterm infants receive mother's own milk (MOM) when available or pasteurized donor breast milk (DBM) when MOM is unavailable. The goal of this study was to determine whether DBM could be inoculated with MOM from mothers of preterm infants to restore the live microbiota (RM). Culture dependent and culture independent methods were used to analyze the fluctuations in the overall population and microbiome, respectively, of DBM, MOM, and RM samples over time. Using MOM at time = 0 (T0) as the target for the restoration process, this level was reached in the 10% (RM-10) and 30% (RM-30) mixtures after 4 h of incubation at 37°C, whereas, the larger dilutions of 1% (RM-1) and 5% (RM-5) after 8 h. The diversity indexes were similar between MOM and DBM samples, however, different genera were prevalent in each group. Interestingly, 40% of the bacterial families were able to expand in DBM after 4 h of incubation indicating that a large percentage of the bacterial load present in MOM can grow when transferred to DBM, however, no core microbiome was identified. In summary, the microbiome analyses indicated that each mother has a unique microbiota and that live microbial reestablishment of DBM may provide these microbes to individual mothers' infants. The agreement between the results obtained from the viable bacterial counts and the microbiome analyses indicate that DBM incubated with 10-30% v/v of the MOM for 4 h is a reasonable restoration strategy.

Necrotizing Enterocolitis and Human Milk Feeding: A Systematic Review

This article summarizes evidence regarding whether a donor human milk (DHM) and/or an exclusively human milk (EHM) diet decreases the incidence of necrotizing enterocolitis (NEC) and the dose of human milk (HM) necessary to reduce the risk of NEC in premature infants. Additional research regarding protection afforded by DHM and EHM is necessary as well as research elucidating the exact dose of HM necessary for NEC risk reduction. Research is also needed to determine whether there is a dose-dependent effect of DHM, a combination of mother's own milk and DHM, and an EHM diet on NEC incidence.

Evaluation of clinicians' knowledge and practices regarding medical radiological exposure: findings from a mixed-methods investigation (survey and qualitative study)

OBJECTIVES

To assess the impact of initiatives aiming to increase clinician awareness of radiation exposure; to explore the challenges they face when communicating with patients; to study what they think is the most appropriate way of communicating the long-term potential risks of medical radiological exposure to patients.

DESIGN

A quantitative and qualitative evaluation through a survey and focal groups.

SETTING

San Juan Hospital and Dr Peset Hospital (Southeast Spain) and clinicians from Spanish scientific societies.

PARTICIPANTS

The surveys were answered (a) in person (216: all the radiologists (30), urologists (14) and surgeons (44) working at both participant hospitals; a sample of general practitioners from the catchment area of one hospital (45), and a consecutive sample of radiologists attending a scientific meeting (60)) or (b) electronically through Spanish scientific societies (299: radiologists (45), pneumologists (123), haematologists (75) and surgeons (40)). Clinicians were not randomly selected and thus the results are limited by the diligence of the individuals filling out the survey.

PRIMARY AND SECONDARY OUTCOME MEASURES

Clinicians' knowledge and practices regarding medical radiological exposure, and what they considered most appropriate for communicating information to patients.

RESULTS

Nearly 80% of the clinicians surveyed had never heard of the European recommendations. Fewer than 20% of the clinicians surveyed identified correctly the radiation equivalence dose of intravenous urography or barium enema. It was reported by 31.7% that they inform patients about the long-term potential risks of ionising radiation. All participants agreed that the most appropriate way to present information is a table with a list of imaging tests and their corresponding radiation equivalence dose in terms of chest X-rays and background radiation exposure.

CONCLUSIONS

Medical radiological exposure is frequently underestimated and rarely explained to patients. With a clear understanding of medical radiological exposure and proper communication tools, clinicians will be able to accurately inform patients.

Cannabinoids suppress acute and anticipatory nausea in preclinical rat models of conditioned gaping

The sensation of nausea is one of the most debilitating human experiences. Current antiemetic therapies are effective in reducing vomiting, but are less effective in reducing acute and delayed nausea and are completely ineffective in reducing anticipatory nausea. Recent preclinical evidence using a selective rat model of nausea (conditioned gaping reactions) has revealed that cannabinoids have great promise as treatments for nausea and that their antinausea effects may be mediated by the interoceptive insular cortex.

Association of timing of initiation of breastmilk expression on milk volume and timing of lactogenesis stage II among mothers of very low-birth-weight infants

BACKGROUND

Feeding breastmilk to premature infants decreases morbidity but is often limited owing to an insufficient milk supply and delayed attainment of lactogenesis stage II. Early initiation of milk expression following delivery has been shown to increase milk production in mothers of very low-birth-weight (VLBW) infants. Although recommendations for milk expression in this population include initiation within 6 hours following delivery, little evidence exists to support these guidelines. This study compared milk volume and timing of lactogenesis stage II in mothers of VLBW infants who initiated milk expression within 6 hours following delivery versus those who initiated expression after 6 hours.

SUBJECTS AND METHODS

Forty mothers of VLBW infants were grouped according to when they initiated milk expression following delivery. Group I began milk expression within 6 hours, and Group II began expression after 6 hours. Milk volume was measured daily for the first 7 days and on Days 21 and 42. Timing of lactogenesis stage II was determined through mothers' perceptions of sudden breast fullness.

RESULTS

Group I produced more breastmilk during the initial expression session and on Days 6, 7, and 42. No difference in timing of lactogenesis stage II was observed. When mothers who began milk expression prior to 1 hour following delivery were removed from analysis, benefits of milk expression within 6 hours were no longer apparent.

CONCLUSIONS

Initiation of milk expression within 6 hours following delivery may not improve lactation success in mothers of VLBW infants unless initiated within the first hour.

Intra-visceral insular cortex 2-arachidonoylglycerol, but not N-arachidonoylethanolamide, suppresses acute nausea-induced conditioned gaping in rats

The visceral insular cortex (VIC) has previously been shown to play a critical role during acute nausea-induced conditioned gaping in rats. Specifically, localized administration of the conventional anti-emetic, ondansetron or the synthetic cannabinoid, HU210, interferes with the establishment of conditioned gaping, likely by reducing the effects of an illness-inducing treatment. However the precise role of the VIC in endocannabinoid-suppression of nausea remains unknown; thus we investigated the potential of localized intra-VIC endocannabinoid administration to interfere with acute nausea-induced conditioned gaping behavior in male Sprague-Dawley rats. Animals received an intraoral infusion of saccharin (0.1%) followed by intra-VIC exogenous N-arachidonoylethanolamide (AEA; 0.4, 4 μg) or 2-arachidonoylglycerol (2-AG; 0.5, 1 μg), and were subsequently injected with nausea-inducing LiCl (0.15M) 15 min later. Bilateral intra-VIC infusions of 2-AG (1 μg, but not 0.5 μg) dose-dependently suppressed conditioned gaping, whereas exogenous AEA was without effect. Interestingly, 2-AG reduced conditioned gaping despite additional pretreatment with the selective cannabinoid receptor type 1 (CB1) antagonist, AM-251; however, concomitant pretreatment with the cyclooxygenase inhibitor, indomethacin (0.5 μg), blocked the suppressive effects of intra-VIC 2-AG. These findings suggest that the modulatory role of the endocannabinoid system during nausea is driven largely by the endocannabinoid, 2-AG, and that its anti-nausea effects may be partly independent of CB1-receptor signaling through metabolic products of the endocannabinoid system.

Effect of low doses of cannabidiolic acid and ondansetron on LiCl-induced conditioned gaping (a model of nausea-induced behaviour) in rats

BACKGROUND AND PURPOSE

To determine the minimally effective dose of cannabidiolic acid (CBDA) that effectively reduces lithium chloride (LiCl)-induced conditioned gaping reactions (nausea-induced behaviour) in rats and to determine if these low systemic doses of CBDA (5-0.1 μg·kg⁻¹) relative to those of CBD could potentiate the anti-nausea effects of the classic 5-hydroxytryptamine 3 (5-HT₃) receptor antagonist, ondansetron (OND).

EXPERIMENTAL APPROACH

We investigated the efficacy of low doses of CBDA to suppress acute nausea, assessed by the establishment of conditioned gaping to a LiCl-paired flavour in rats. The potential of threshold and subthreshold doses of CBDA to enhance the reduction of nausea-induced conditioned gaping by OND were then determined.

KEY RESULTS

CBDA (at doses as low as 0.5 μg·kg⁻¹) suppressed nausea-induced conditioned gaping to a flavour. A low dose of OND (1.0 μg·kg⁻¹) alone reduced nausea-induced conditioned gaping, but when it was combined with a subthreshold dose of CBDA (0.1 μg·kg⁻¹) there was an enhancement in the suppression of LiCl-induced conditioned gaping.

CONCLUSIONS AND IMPLICATIONS

CBDA potently reduced conditioned gaping in rats, even at low doses and enhanced the anti-nausea effect of a low dose of OND. These findings suggest that combining low doses of CBDA and OND will more effectively treat acute nausea in chemotherapy patients.

Tetrahydrocannabinolic acid reduces nausea-induced conditioned gaping in rats and vomiting in Suncus murinus

BACKGROUND AND PURPOSE

We evaluated the anti-emetic and anti-nausea properties of the acid precursor of Δ(9) -tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), and determined its mechanism of action in these animal models.

EXPERIMENTAL APPROACH

We investigated the effect of THCA on lithium chloride- (LiCl) induced conditioned gaping (nausea-induced behaviour) to a flavour, and context (a model of anticipatory nausea) in rats, and on LiCl-induced vomiting in Suncus murinus. Furthermore, we investigated THCA's ability to induce hypothermia and suppress locomotion [rodent tasks to assess cannabinoid1 (CB1 ) receptor agonist-like activity], and measured plasma and brain THCA and THC levels. We also determined whether THCA's effect could be blocked by pretreatment with SR141716 (SR, a CB1 receptor antagonist).

KEY RESULTS

In rats, THCA (0.05 and/or 0.5 mg·kg(-1) ) suppressed LiCl-induced conditioned gaping to a flavour and context; the latter effect blocked by the CB1 receptor antagonist, SR, but not by the 5-hydroxytryptamine-1A receptor antagonist, WAY100635. In S. murinus, THCA (0.05 and 0.5 mg·kg(-1) ) reduced LiCl-induced vomiting, an effect that was reversed with SR. A comparatively low dose of THC (0.05 mg·kg(-1) ) did not suppress conditioned gaping to a LiCl-paired flavour or context. THCA did not induce hypothermia or reduce locomotion, indicating non-CB1 agonist-like effects. THCA, but not THC was detected in plasma samples.

CONCLUSIONS AND IMPLICATIONS

THCA potently reduced conditioned gaping in rats and vomiting in S. murinus, effects that were blocked by SR. These data suggest that THCA may be a more potent alternative to THC in the treatment of nausea and vomiting.

Anandamide transport inhibition by ARN272 attenuates nausea-induced behaviour in rats, and vomiting in shrews (Suncus murinus)

BACKGROUND AND PURPOSE

To understand how anandamide transport inhibition impacts the regulation of nausea and vomiting and the receptor level mechanism of action involved. In light of recent characterization of an anandamide transporter, fatty acid amide hydrolase-1-like anandamide transporter, to provide behavioural support for anandamide cellular reuptake as a facilitated transport process.

EXPERIMENTAL APPROACH

The systemic administration of the anandamide transport inhibitor ARN272 ([(4-(5-(4-hydroxy-phenyl)-3,4-diaza-bicyclo[4.4.0]deca-1(6),2,4,7,9-pentaen-2-ylamino)-phenyl)-phenylamino-methanone]) was used to evaluate the prevention of LiCl-induced nausea-induced behaviour (conditioned gaping) in rats, and LiCl-induced emesis in shrews (Suncus murinus). The mechanism of how prolonging anandamide availability acts to regulate nausea in rats was explored by the antagonism of cannabinoid 1 (CB1) receptors with the systemic co-administration of SR141716.

KEY RESULTS

The systemic administration of ARN272 produced a dose-dependent suppression of nausea-induced conditioned gaping in rats, and produced a dose-dependent reduction of vomiting in shrews. The systemic co-administration of SR141716 with ARN272 (at 3.0 mg·kg(-1)) in rats produced a complete reversal of ARN272-suppressed gaping at 1.0 mg·kg(-1). SR141716 alone did not differ from the vehicle solution.

CONCLUSIONS AND IMPLICATIONS

These results suggest that anandamide transport inhibition by the compound ARN272 tonically activates CB1 receptors and as such produces a type of indirect agonism to regulate toxin-induced nausea and vomiting. The results also provide behavioural evidence in support of a facilitated transport mechanism used in the cellular reuptake of anandamide.

Cannabidiolic acid prevents vomiting in Suncus murinus and nausea-induced behaviour in rats by enhancing 5-HT1A receptor activation

BACKGROUND AND PURPOSE

To evaluate the ability of cannabidiolic acid (CBDA) to reduce nausea and vomiting and enhance 5-HT(1A) receptor activation in animal models.

EXPERIMENTAL APPROACH

We investigated the effect of CBDA on (i) lithium chloride (LiCl)-induced conditioned gaping to a flavour (nausea-induced behaviour) or a context (model of anticipatory nausea) in rats; (ii) saccharin palatability in rats; (iii) motion-, LiCl- or cisplatin-induced vomiting in house musk shrews (Suncus murinus); and (iv) rat brainstem 5-HT(1A) receptor activation by 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and mouse whole brain CB(1) receptor activation by CP55940, using [³⁵S]GTPγS-binding assays.

KEY RESULTS

In shrews, CBDA (0.1 and/or 0.5 mg·kg⁻¹ i.p.) reduced toxin- and motion-induced vomiting, and increased the onset latency of the first motion-induced emetic episode. In rats, CBDA (0.01 and 0.1 mg·kg⁻¹ i.p.) suppressed LiCl- and context-induced conditioned gaping, effects that were blocked by the 5-HT(1A) receptor antagonist, WAY100635 (0.1 mg·kg⁻¹ i.p.), and, at 0.01 mg·kg⁻¹ i.p., enhanced saccharin palatability. CBDA-induced suppression of LiCl-induced conditioned gaping was unaffected by the CB₁ receptor antagonist, SR141716A (1 mg·kg⁻¹ i.p.). In vitro, CBDA (0.1-100 nM) increased the E(max) of 8-OH-DPAT.

CONCLUSIONS AND IMPLICATIONS

Compared with cannabidiol, CBDA displays significantly greater potency at inhibiting vomiting in shrews and nausea in rats, and at enhancing 5-HT(1A) receptor activation, an action that accounts for its ability to attenuate conditioned gaping in rats. Consequently, CBDA shows promise as a treatment for nausea and vomiting, including anticipatory nausea for which no specific therapy is currently available.

2-arachidonoylglycerol interferes with lithium-induced vomiting in the house musk shrew, Suncus murinus

The role of the endocannabinoid system in vomiting has been previously studied using several animal species. These investigations have clearly demonstrated an anti-emetic role for the eCB, anandamide, in these animal models; however, research concerning the role of 2-arhachidonoylglycerol (2AG) has been less clear. The aim of the present study was to assess the effects of exogenous 2AG administration in the house musk shrew, Suncus murinus. In Experiment 1, shrews were injected with vehicle or 2AG (1, 2, 5, 10 mg/kg) 15 min prior to behavioral testing in which the frequency of vomiting episodes was observed. In Experiment 2, shrews were pre-treated with 2AG (2, 5 mg/kg) prior to being administered the emetic drug, lithium chloride (LiCl). It was found that 2AG alone did not induce emesis, but interfered with vomiting in response to LiCl administration. The anti-emetic effects of 2AG in Suncus murinus do not appear to be mediated by CB1 receptors, as concomitant pretreatment with the CB1 receptor antagonist, SR141716, did not reverse the suppressive effects of 2AG. These results confirm that manipulations that increase levels of 2AG exert anti-emetic effects in the house musk shrew.

The anti-nausea effects of CB1 agonists are mediated by an action at the visceral insular cortex

BACKGROUND AND PURPOSE

Conditioned gaping reactions reflect nausea-induced behaviour in rats. Cannabinoid 1 receptor (CB(1) ) agonists interfere with the establishment of nausea-induced conditioned gaping; however, it is not known if their effects are mediated by an action at peripheral or central CB(1) receptors.

EXPERIMENTAL APPROACH

We utilized the conditioned gaping model of nausea to evaluate the effect of peripheral and central administration of the peripherally restricted CB(1) agonist, CB13, on the establishment of LiCl-induced gaping in rats. We further evaluated the ability of HU-210 administered to the gustatory insular cortex (GIC) or visceral insular cortex (VIC) to interfere with LiCl-induced conditioned gaping and determined if this effect was mediated by CB(1) receptors.

KEY RESULTS

Central, but not peripheral, CB13 suppressed LiCl-induced conditioned gaping. Central administration of the potent CB(1) agonist, HU-210, delivered to the VIC, but not the GIC, suppressed the establishment of LiCl-induced gaping reactions, but not LiCl-induced suppression of hedonic reactions or conditioned taste avoidance. This pattern of results suggests that HU-210 delivered to the VIC prevented LiCl-induced nausea, but not learning per se. The suppression of LiCl-induced conditioned gaping by HU-210 was mediated by CB(1) receptors because it was prevented by co-administration of CB(1) antagonist/inverse agonist, AM-251, into the VIC. A high dose of AM-251 (20 µg) administered alone into the VIC did not produce conditioned gaping reactions.

CONCLUSIONS AND IMPLICATIONS

The nausea-relieving effects of CB(1) agonists, but not the nausea-inducing effects of CB(1) inverse agonists, are mediated, at least in part, by their action at the VIC in rats.

Cannabidiol, a non-psychotropic component of cannabis, attenuates vomiting and nausea-like behaviour via indirect agonism of 5-HT(1A) somatodendritic autoreceptors in the dorsal raphe nucleus

BACKGROUND AND PURPOSE

To evaluate the hypothesis that activation of somatodendritic 5-HT(1A) autoreceptors in the dorsal raphe nucleus (DRN) produces the anti-emetic/anti-nausea effects of cannabidiol (CBD), a primary non-psychoactive cannabinoid found in cannabis.

EXPERIMENTAL APPROACH

The potential of systemic and intra-DRN administration of 5-HT(1A) receptor antagonists, WAY100135 or WAY100635, to prevent the anti-emetic effect of CBD in shrews (Suncus murinus) and the anti-nausea-like effects of CBD (conditioned gaping) in rats were evaluated. Also, the ability of intra-DRN administration of CBD to produce anti-nausea-like effects (and reversal by systemic WAY100635) was assessed. In vitro studies evaluated the potential of CBD to directly target 5-HT(1A) receptors and to modify the ability of the 5-HT(1A) agonist, 8-OH-DPAT, to stimulate [(35) S]GTPγS binding in rat brainstem membranes.

KEY RESULTS

CBD suppressed nicotine-, lithium chloride (LiCl)- and cisplatin (20 mg·kg(-1) , but not 40 mg·kg(-1) )-induced vomiting in the S. murinus and LiCl-induced conditioned gaping in rats. Anti-emetic and anti-nausea-like effects of CBD were suppressed by WAY100135 and the latter by WAY100635. When administered to the DRN: (i) WAY100635 reversed anti-nausea-like effects of systemic CBD, and (ii) CBD suppressed nausea-like effects, an effect that was reversed by systemic WAY100635. CBD also displayed significant potency (in a bell-shaped dose-response curve) at enhancing the ability of 8-OH-DPAT to stimulate [(35) S]GTPγS binding to rat brainstem membranes in vitro. Systemically administered CBD and 8-OH-DPAT synergistically suppressed LiCl-induced conditioned gaping.

CONCLUSIONS AND IMPLICATIONS

These results suggest that CBD produced its anti-emetic/anti-nausea effects by indirect activation of the somatodendritic 5-HT(1A) autoreceptors in the DRN.

LINKED ARTICLES

This article is part of a themed section on Cannabinoids in Biology and Medicine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-8. To view Part I of Cannabinoids in Biology and Medicine visit http://dx.doi.org/10.1111/bph.2011.163.issue-7.

GEBR-7b, a novel PDE4D selective inhibitor that improves memory in rodents at non-emetic doses

BACKGROUND AND PURPOSE

Strategies designed to enhance cerebral cAMP have been proposed as symptomatic treatments to counteract cognitive deficits. However, pharmacological therapies aimed at reducing PDE4, the main class of cAMP catabolizing enzymes in the brain, produce severe emetic side effects. We have recently synthesized a 3-cyclopentyloxy-4-methoxybenzaldehyde derivative, structurally related to rolipram, and endowed with selective PDE4D inhibitory activity. The aim of the present study was to investigate the effect of the new drug, namely GEBR-7b, on memory performance, nausea, hippocampal cAMP and amyloid-β (Aβ) levels.

EXPERIMENTAL APPROACH

To measure memory performance, we performed object recognition tests on rats and mice treated with GEBR-7b or rolipram. The emetic potential of the drug, again compared with rolipram, was evaluated in rats using the taste reactivity test and in mice using the xylazine/ketamine anaesthesia test. Extracellular hippocampal cAMP was evaluated by intracerebral microdialysis in freely moving rats. Levels of soluble Aβ peptides were measured in hippocampal tissues and cultured N2a cells by elisa.

KEY RESULTS

GEBR-7b increased hippocampal cAMP, did not influence Aβ levels and improved spatial, as well as object memory performance in the object recognition tests. The effect of GEBR-7b on memory was 3 to 10 times more potent than that of rolipram, and its effective doses had no effect on surrogate measures of emesis in rodents.

CONCLUSION AND IMPLICATIONS

Our results demonstrate that GEBR-7b enhances memory functions at doses that do not cause emesis-like behaviour in rodents, thus offering a promising pharmacological perspective for the treatment of memory impairment.

A novel peripherally restricted cannabinoid receptor antagonist, AM6545, reduces food intake and body weight, but does not cause malaise, in rodents

BACKGROUND AND PURPOSE

Cannabinoid CB(1) receptor antagonists reduce food intake and body weight, but clinical use in humans is limited by effects on the CNS. We have evaluated a novel cannabinoid antagonist (AM6545) designed to have limited CNS penetration, to see if it would inhibit food intake in rodents, without aversive effects.

EXPERIMENTAL APPROACH

Cannabinoid receptor binding studies, cAMP assays, brain penetration studies and gastrointestinal motility studies were carried out to assess the activity profile of AM6545. The potential for AM6545 to induce malaise in rats and the actions of AM6545 on food intake and body weight were also investigated.

KEY RESULTS

AM6545 binds to CB(1) receptors with a K(i) of 1.7 nM and CB(2) receptors with a K(i) of 523 nM. AM6545 is a neutral antagonist, having no effect on cAMP levels in transfected cells and was less centrally penetrant than AM4113, a comparable CB(1) receptor antagonist. AM6545 reversed the effects of WIN55212-2 in an assay of colonic motility. In contrast to AM251, AM6545 did not produce conditioned gaping or conditioned taste avoidance in rats. In rats and mice, AM6545 dose-dependently reduced food intake and induced a sustained reduction in body weight. The effect on food intake was maintained in rats with a complete subdiaphragmatic vagotomy. AM6545 inhibited food intake in CB(1) receptor gene-deficient mice, but not in CB(1)/CB(2) receptor double knockout mice.

CONCLUSIONS AND IMPLICATIONS

Peripherally active, cannabinoid receptor antagonists with limited brain penetration may be useful agents for the treatment of obesity and its complications.

Inverse agonism of cannabinoid CB1 receptors potentiates LiCl-induced nausea in the conditioned gaping model in rats

BACKGROUND AND PURPOSE

Cannabinoid CB(1) receptor antagonists/inverse agonists, potentiate toxin-induced nausea and vomiting in animal models. Here, we sought to determine if this potentiated nausea was mediated by inverse agonism or neutral antagonism of the CB(1) receptor, and if the potentiated nausea would be produced by intracerebroventricular (icv) administration of an inverse agonist.

EXPERIMENTAL APPROACH

The conditioned gaping model of nausea in rats was used to compare the CB(1) receptor antagonist/inverse agonist, AM251, and the CB(1) receptor neutral antagonists, AM6527 (centrally and peripherally active) and AM6545 (peripherally active), in potentiating conditioned gaping produced by lithium chloride (LiCl) solution. The effect of icv (lateral ventricle and 4th ventricle) administration of AM251 on LiCl-induced gaping in this model was also evaluated.

KEY RESULTS

At a dose that did not produce conditioned gaping on its own, systemically administered AM251 (1.25 mg.kg(-1)) potentiated LiCl-induced conditioned gaping and reduced sucrose palatability; however, even doses as high as 8 mg.kg(-1) of AM6545 and AM6527 neither potentiated LiCl-induced conditioned gaping nor reduced sucrose palatability. Infusions of AM251 into the lateral ventricles (1.25, 12.5 and 125 microg) or the 4th ventricle (2.5, 12.5 and 125 microg) did not potentiate LiCl-induced conditioned gaping reactions, but all doses attenuated saccharin palatability during the subsequent test.

CONCLUSIONS AND IMPLICATIONS

Inverse agonism, but not neutral antagonism, of CB(1) receptors potentiated toxin-induced nausea. This effect may be peripherally mediated or may be mediated centrally by action on CB(1) receptors, located distal to the cerebral ventricles.

The FAAH inhibitor URB-597 interferes with cisplatin- and nicotine-induced vomiting in the Suncus murinus (house musk shrew)

Considerable evidence implicates the endocannabinoid system as a neuromodulator of nausea and vomiting. The action of anandamide (AEA) can be prolonged by inhibiting its degradation, through the use of URB597 (URB), a Fatty Acid Amide Hydrolase (FAAH) enzyme inhibitor. Here we present evidence that the FAAH inhibitor, URB, interferes with cisplatin- and nicotine-induced vomiting in the Suncus murinus. In Experiment 1, shrews were injected with URB (0.9 mg/kg) or vehicle 120 min prior to the behavioral testing. They received a second injection of AEA (5 mg/kg) or vehicle 15 min prior to being injected with cisplatin (20 mg/kg) or saline and the number of vomiting episodes were counted for 60 min. In Experiment 2, shrews were injected with vehicle or URB (0.9 mg/kg) 120 min prior to receiving an injection of nicotine (5 mg/kg) or saline and the number of vomiting episodes were counted for 15 min. Experiment 3 evaluated the potential of the CB(1) antagonist, SR141716, to reverse the effect of URB on nicotine-induced vomiting. URB attenuated vomiting produced by cisplatin and nicotine and the combination of URB+AEA suppressed vomiting produced by cisplatin. The effect of URB on nicotine-induced vomiting was reversed by SR141716. These data suggest that the EC system plays a tonic role in the regulation of toxin-induced vomiting.

Part 2: Birth trauma: injuries to the intraabdominal organs, peripheral nerves, and skeletal system

Part 1 of this 2-part article, "Early Recognition and Treatment of Birth Trauma: Injuries to the Head and Face" provided readers with basic concepts related to birth trauma to the head and face. Part 2 focuses on the pathophysiology, etiology, diagnosis, treatment, and prognosis of birth injuries to the intraabdominal organs, the peripheral nerves, the spinal cord, and the skeletal system. Risk factors for birth injury to these areas are discussed along with key issues related to the nursing care of affected infants.