The association between labour epidural case volume and the rate of accidental dural puncture

Accidental dural puncture is a recognised complication of labour epidural placement and can cause a debilitating headache. We examined the association between labour epidural case volume and accidental dural puncture rate in specialist anaesthetists and anaesthesia trainees. We performed a retrospective cohort study of labour epidural and combined spinal-epidural nerve blocks performed between 1 July 2013 and 31 December 2017 at Waitemata District Health Board, Auckland, New Zealand. The mean (SD) annual number of obstetric epidural and combined spinal-epidural procedures for high-case volume specialists was 44.2 (15.0), and for low-case volume specialists was 10.0 (6.8), after accounting for caesarean section combined spinal-epidural procedures. Analysis of 7976 labour epidural and combined spinal-epidural procedure records revealed a total of 92 accidental dural punctures (1.2%). The accidental dural puncture rate (95%CI) in high-case volume specialists was 0.6% (0.4-0.9%) and in low-case volume specialists 2.4% (1.4-3.9%), indicating probable skill decay. The odds of accidental dural puncture were 3.77 times higher for low- compared with high-case volume specialists (95%CI 1.72-8.28, p = 0.001). Amongst trainees, novices had a significantly higher accidental dural puncture complication rate (3.1%) compared with registrars (1.2%), OR (95%CI) 0.39 (0.18-0.84), p = 0.016, or fellows (1.1%), 0.35 (0.16-0.76), p = 0.008. Accidental dural puncture complication rates decreased once trainees progressed past the 'novice' training stage.

0888 A Peer-Based Social Media Intervention to Promote Continuous Positive Airway Pressure Adherence in Adolescents With Obstructive Sleep Apnea

Introduction

Continuous positive airway pressure (CPAP) adherence in adolescents with obstructive sleep apnea (OSA) is suboptimal. This study evaluated an innovative CPAP adherence intervention for adolescents and their caregivers delivered via private Facebook groups. Study aims: (1) determine feasibility and acceptability of the intervention and (2) assess CPAP use pre- and post-intervention.

Methods

A pilot cohort study design was employed (N=6 dyads). Intervention included psychoeducation, CPAP use downloads/feedback, promoting peer-engagement through posts, videos, and polls. Adolescent and caregiver groups ran separately and simultaneously over 4-weeks. Measures: demographics, engagement/participation data, CPAP use, semi-structured interviews. Analysis: descriptive statistics and thematic content analysis.

Results

Adolescents were Black/African American (100%), males (100%) with a median age of 16 years (range 13-17). Caregivers (n=6) were mothers (67%) and fathers (33%) with a median age of 47 years (range 38-55). Caregivers were more engaged with the intervention than adolescents, viewing content 65%, 75%, 85%, 90%, and 100% (n=2) of days versus adolescents who viewed content 0%, 20% (n=2), 40%, 75% and 100%. Semi-structured interviews revealed the intervention was perceived positively; learning/expanded knowledge, gaining a sense of community, and enjoyment in the opportunity to help others were commonly identified. Interview feedback revealed utilizing a different social media platform may be more beneficial for adolescent engagement. Participants noted the intervention promoted conversations between the adolescent and caregiver, and 4/6 teens cited increased motivation to use CPAP. Average CPAP use increased in 50% of participants (n=3); 33% (n=2) sustained their use, and one decreased use.

Conclusion

Participants consistently noted appreciation for knowledge gained and sense of community derived from the intervention. This study supports the potential utilization of social media platforms to not only provide reliable OSA/CPAP education but to also promote peer-engagement. Given the acceptability and increased CPAP use in this small sample, a larger trial is indicated.

Support

Lead author receives support from NIH/NHLBI Award T32 HL07953. Videos included in intervention supported by The Children’s Hospital of Philadelphia Metabolism, Nutrition and Development Research Affinity Group Pilot and Feasibility Grant.

0885 Reduction in Emergency Department and Inpatient Hospitalization Visits and Length of Stay in a Cohort of Pediatric Patients Initiated on Positive Airway Pressure for Obstructive Sleep Apnea Syndrome

Introduction

Positive Airway Pressure (PAP) is an efficacious treatment of pediatric obstructive sleep apnea syndrome (OSAS). However, it is unknown whether PAP initiation is associated with reduced healthcare utilization, an important metric of care management. We hypothesized that healthcare utilization would be reduced after initiation of PAP in a cohort of pediatric patients prescribed PAP for OSAS.

Methods

Data were extracted from electronic medical records of 475 patients (Mean±SD age at PAP initiation=7.7±5.7 years; 58.7% male; 40.6% White; 38.3% Black; 18.1% multiracial/other; 12.1% Hispanic/Latinx) prescribed PAP for OSAS and followed in our Sleep Center quality improvement program. We extracted the total number of emergency department (ED) visits and hospitalizations and computed the related average length of stay (LOS) in hours for these visits in the 18 months prior to and 18 months following PAP initiation.

Results

Paired samples t-tests showed that number of ED visits and hospitalizations, and the related visit LOS, were significantly reduced following PAP initiation. The average number of visits reduced from 2.20 pre-PAP to 1.77 post-PAP initiation [t(474) = 3.48, p<.001, effect size = 0.16], while average LOS reduced from 185.14 hours pre-PAP to 42.94 hours post-PAP initiation [t(474) = 4.81, p<.001, effect size = 0.29]. Findings for the significant reduction in LOS held after adjusting for the number of pre and post-PAP ED visits and hospitalizations, average pre-PAP LOS, and patient demographics (age at the time of initiation; sex; race/ethnicity) using multiple linear regression.

Conclusion

PAP initiation was associated with fewer and shorter ED visits and hospitalizations in a large sample of pediatric patients. We speculate that PAP initiation could help reduce morbidity associated with pediatric OSAS, as well as improve healthcare utilization, capacity management and care in this population.

Support

K23HD094905 and Sleep Research Foundation (AAW)

The varying effects of a range of preservatives on Myoviridae and Siphoviridae bacteriophages formulated in a semi-solid cream preparation

Bacteriophages may be formulated into semi-solid bases for therapeutic delivery. This work investigated the effects of a range of preservatives on the viability of Myoviridae and Siphoviridae bacteriophages when these were formulated into a standard semi-solid cream base. The six preservatives tested included: benzoic acid (0·1%), chlorocresol (0·1%), combination hydroxybenzoates (propyl 4-hydroxybenzoates with methyl 4-hydroxybenzoates) (0·1%), methyl 4-hydroxybenzoate (0·08%), 2-phenoxyethanol (1%) and propyl 4-hydroxybenzoate (0·02%). These were each formulated into cetomacrogol cream aqueous to generate six individual semi-solid bases into which Myoviridae and Siphoviridae bacteriophages were added and tested for stability. Optimal bacteriophage stability was seen when the preservative chlorocresol was used. Bacteriophage in the acidic benzoic acid were the least stable, resulting in complete loss of viability after 4-5 weeks. Of the bacteriophages tested, the Myoviridae KOX1 was significantly more stable than the Siphoviridae PAC1 after 91 days in formulations with each of the preservatives. Our results suggest the need for individual testing of specific bacteriophages in pharmaceutical formulations, as their efficacy when exposed to preservatives and excipients in these delivery forms may vary. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriophages are being increasingly investigated as alternatives to antibiotics. While bacteriophages can be formulated in diverse ways for therapeutic delivery, there has been scant work on how excipients and preservatives in these formulations affect stability of different bacteriophages. We demonstrate that the nature of preservatives in formulations will affect bacteriophage stability, and that in these formulations, viability of bacteriophage differs according to their morphology. Our work highlights the need for individual testing of specific bacteriophages in pharmaceutical formulations, as efficacy when exposed to preservatives and excipients in these delivery forms may vary.

ICT-Based Comprehensive Health and Social-Needs Assessment System for Supporting Person-Centered Community Care

Objectives

This study developed an information and communication technology (ICT)-based comprehensive health and social-needs assessment (CHSNA) system based on the International Classification of Functioning, Disability, and Health (ICF) with the aim of enhancing person-centered community care for community residents and supporting healthcare professionals and social workers who provide healthcare and social services in the community.

Methods

Items related to a CHSNA tool were developed and mapped with ICF codes. Experts validated the CHSNA system design and process using the Delphi method, and a pilot test of the initial version of the system was conducted.

Results

The following three steps of CHSNA were embedded in the system, which had a user-friendly screen and images: basic health assessment, life and activity assessment, and in-depth health assessment. The assessment results for the community residents were presented with visualized health profiles, including images, graphs, and an ICF model.

Conclusions

The developed CHSNA system can be used by healthcare professionals, social workers, and community residents to evaluate the reasoning underlying health and social needs, to facilitate the identification of more appropriate healthcare plans, and to guide community residents to receive the best healthcare services. A CHSNA system can improve the implementation of standardized terminology utilizing the ICF and the accuracy of needs assessments of community residents.

Pilot Testing of an ICT-Based Care Management Support System to Deliver Integrated Community Care

The purpose of this study was to develop an ICT-based care-management support system and to assess its validity and applicability through pilot testing. The system links users' health and social needs to community resources. Users and care managers participated in each step of care management through an interactive decision support system. The system contributes to facilitate person-centered community care.

Development of ICT-Based Comprehensive Health and Social-Needs Assessment System to Enhance Person-Centered Community Care

We developed a comprehensive health and social-need assessment system to evaluate the diverse needs of elders with chronic illnesses in the community and to enhance the connection of their needs to health and social services. A comprehensive needs-assessment tool and profiles were integrated into the ICT system. We found that care managers could assess elders' needs comprehensively and connect those needs to suitable health and social services systematically.

Stabilization and sustained-release effect of misoprostol with methacrylate copolymer

The use of ammonio methacrylate copolymer (Eudrgit RS, RL) to form a sustained-release solid dispersion of Misoprostol can improve and enhance two important physical and chemical properties of Misoprostol. First, the solid dispersion matrix formed by the copolymer can protect Misoprostol from being degraded by water so that its stability is improved. Second, Misoprostol can be slowly released by diffusion from the copolymer matrix. Accelerated stability studies of Misoprostol-Eudragit solid dispersion after storing at various temperatures for different time periods were carried out. According to high performance liquid chromatography (HPLC) analyses, the stability of Misoprostol in a series of Eudragit appeared significantly improved at different ratios. The Misoprostol-Eudragit dispersion can be used in a powder form, filled in capsules, or compressed into tablets. The dissolution profiles of Misoprostol-Eudragit solid dispersion and its tablets in water, pH 1. 2, 4.5 and 6.8, dissolution media show that this stable solid dispersion is a sustained-release type.

Relative bioavailability of salmon calcitonin given intramuscularly

BACKGROUND

Salmon calcitonin, a polypeptide hormone, is used in the treatment of osteoporosis, hypercalcemia and Paget's disease. The purpose of this study was to evaluate the pharmacokinetics and relative bioavailability of two salmon calcitonin products, Miacalcic (Novartis Pharmaceuticals, Basle, Switzerland) and Calcinin (Purzer Pharmaceuticals, Taipei, Taiwan).

METHODS

This was a randomized, single-dose, crossover study conducted under fasting conditions with a washout period of 1 week between doses. Ten healthy male subjects were enrolled in this study. Each subject received a 100 IU dose (20 micrograms; 50 IU/ampule x 2) of salmon calcitonin intramuscularly (i.m.) followed by collection of blood samples at specified time intervals. Serum salmon calcitonin concentrations were measured using a validated radioimmunoassay method with a detection limit of 15.0 pg/ml. Values for the area under the serum concentration from time zero to last time and infinity curve (AUC0-t and AUC0-infinity), peak concentration (Cmax), time to peak concentration, terminal first order rate constant, terminal half-life, mean residence time, total clearance divided by absolute bioavailability, onset time, maximal effect and duration were compared for each product.

RESULTS

The 90% confidence intervals for AUC0-t, AUC0-infinity and Cmax after logarithmic transformation were 93.2% to 113.1%, 97.2% to 114.9% and 84.9% to 108.0%, respectively.

CONCLUSIONS

Based on the two one-sided tests procedure, we conclude that Miacalcic and Calcinin are bioequivalent.

Phosphorylation of paxillin via the ERK mitogen-activated protein kinase cascade in EL4 thymoma cells

Intracellular signals can regulate cell adhesion via several mechanisms in a process referred to as "inside-out" signaling. In phorbol ester-sensitive EL4 thymoma cells, phorbol-12-myristate 13-acetate (PMA) induces activation of extracellular signal-regulated kinase (ERK) mitogen-activated protein kinases and promotes cell adhesion. In this study, clonal EL4 cell lines with varying abilities to activate ERKs in response to PMA were used to examine signaling events occurring downstream of ERK activation. Paxillin, a multifunctional docking protein involved in cell adhesion, was phosphorylated on serine/threonine residues in response to PMA treatment. This response was correlated with the extent and time course of ERK activation. PMA-induced phosphorylation of paxillin was inhibited by compounds that block the ERK activation pathway in EL4 cells, primary murine thymocytes, and primary murine splenocytes. Paxillin was phosphorylated in vitro by purified active ERK2. Two-dimensional electrophoresis revealed that PMA treatment generated a complex pattern of phosphorylated paxillin species in intact cells, some of which were generated by ERK-mediated phosphorylation in vitro. An ERK pathway inhibitor interfered with PMA-induced adhesion of sensitive EL4 cells to substrate. These findings describe a novel inside-out signaling pathway by which the ERK cascade may regulate events involved in adhesion.

Prevention of colonic aberrant crypt foci and modulation of large bowel microbial activity by dietary coffee fiber, inulin and pectin

The present experiments were aimed at developing novel dietary fibers to aid in reduction of colon cancer risk. We assessed the effects of coffee (non-fiber fraction), coffee fiber (arabino-galactose polymer) and inulin (oligo-fructose) in male F344 rats using formation of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in the colon as the measure of preventive efficacy (or lack of such). At 5 weeks of age, groups of rats were fed the AIN-76A (control) and experimental diets that contained 1% coffee, 10% coffee fiber, 10% inulin, 10% pectin (positive control for fiber) or 200 p.p.m. piroxicam (a known ACF inhibitor). At 7 weeks of age, all animals were s.c injected with AOM (15 mg/kg body wt) once weekly for 2 weeks. All rats were killed 8 weeks after the last AOM injection and ACF were counted. The contents of the cecum were analyzed for bacterial beta-glucuronidase activity and short-chain fatty acids (SCFAs). Dietary administration of coffee fiber significantly suppressed AOM-induction of colonic ACF, in terms of total number, as well as crypt multiplicity and number of ACF/cm2 colon (P < 0.01-0.001). Inulin diet had no significant effect on total ACF, but had reduced the number of ACF/cm2 (P < 0.05). Whereas coffee had no effect on ACF formation, 10% pectin diet and 200 p.p.m. piroxicam significantly suppressed colonic ACF (P < 0.001) as had been expected. A significant reduction of cecal beta-glucuronidase activity was observed in the rats fed coffee, coffee fiber and pectin diets. Further, coffee fiber, inulin and pectin increased cecal SCFA levels 3- to 5-fold. These results suggest that coffee fiber can prevent colon cancer risk. Further studies are warranted to determine the full potential of this fiber in pre-clinical efficacy studies.

In vitro expansion of hematopoietic stem cells

We have investigated the effects of interleukin 3 (IL-3) and IL-1 on in vitro expansion of murine hematopoietic progenitors and stem cells using a highly purified progenitor population. Lineage negative, Ly-6A/E+, c-kit+ bone marrow cells from male mice were cultured in suspension in the presence of stem cell factor, IL-6, IL-11 and erythropoietin with or without IL-3 or IL-1. An exponential increase in total nucleated cell counts and about a 10-fold enhancement of nucleated cells by IL-3 were observed during the initial 10 days. Addition of IL-3 hastened the development but significantly suppressed the peak production of colony-forming cells. Addition of IL-1 also significantly suppressed the numbers of progenitors. We then tested the reconstituting ability of the cultured cells by transplanting cells together with "compromised" marrow cells into lethally irradiated mice. The cells expanded from enriched cells in the absence of IL-3 or IL-1 revealed engraftment at two, six and 10 months, while addition of IL-3 or IL-1 to the cultures significantly reduced the reconstituting ability. IL-3 and IL-1 may have negative modulatory effects on the self-renewal of stem cells.

In vitro expansion of hematopoietic progenitors and maintenance of stem cells: comparison between FLT3/FLK-2 ligand and KIT ligand

The effects of FLT3/FLK-2 ligand (FL) and KIT ligand (KL) on in vitro expansion of hematopoietic stem cells were studied using lineage-negative (Lin-)Sca-1-positive (Sca-1+) c-kit-positive (c-kit+) marrow cells from 5-fluorouracil (5-FU)-treated mice. As single agents, neither FL nor KL could effectively support the proliferation of enriched cells in suspension culture. However, in combination with interleukin-11 (IL-11), both FL and KL enhanced the production of nucleated cells and progenitors. The kinetics of stimulation by FL was different from that by KL in that the maximal expansion by FL of the nucleated cell and progenitor pools required a longer incubation than with KL. We then tested the reconstituting abilities of cells cultured for 1, 2, and 3 weeks by transplanting the expanded Ly5.1 cells together with "compromised" marrow cells into lethally irradiated Ly5.2 mice. Cells that had been expanded with either cytokine combination were able to maintain the reconstituting ability of the original cells. Only cells that had been incubated with KL and IL-11 for 21 days had less reconstituting ability than fresh marrow cells. These results indicate that there can be significant expansion of progenitors in vitro without compromising the reconstituting ability of stem cells. Addition of IL-3 to permissive cytokine combinations significantly reduced the ability of cultured cells to reconstitute the hematopoiesis of irradiated hosts. These observations should provide a basis for a rational approach to designing cytokine combinations for in vitro expansion of hematopoietic stem cells.

Soluble thrombopoietin receptor (Mpl) and granulocyte colony-stimulating factor receptor directly stimulate proliferation of primitive hematopoietic progenitors of mice in synergy with steel factor or the ligand for Flt3/Flk2

In an effort to establish the specificity of the thrombopoietin (TPO) effects on murine multipotential progenitors, we tested the effects of soluble TPO receptor (sTPOR; sMpl) on multilineage colony formation that was supported by a combination of TPO and steel factor (SF). Surprisingly, sTPOR did not suppress colony formation from primitive progenitors. This led to the discovery that sTPOR synergizes with SF or Flt3/Flk2 ligand (FL) to support the formation of various types of hematopoietic colonies including multilineage colonies. The colonies supported by the combination of sTPOR and SF were capable of expressing both myeloid and B-lymphoid potentials. Studies using micromanipulation and serum-free culture showed that the effects of sTPOR and SF on the primitive progenitors are direct, not mediated by contaminating stromal cells, and not dependent on factors present in the serum. TPOR belongs to the cytokine receptor group that includes granulocyte colony-stimulating factor receptor (G-CSFR) and erythropoietin receptor (EPOR). Therefore, we tested the effects of sG-CSFR and sEPOR on primitive progenitors. sG-CSFR, but not sEPOR, was able to synergize with SF or FL in supporting the proliferation of primitive progenitors. The direct effects of the soluble receptors appear to be mediated through interactions with their respective membrane-bound receptors expressed on the primitive hematopoietic progenitors.

Thrombopoietin, the ligand for the Mpl receptor, synergizes with steel factor and other early acting cytokines in supporting proliferation of primitive hematopoietic progenitors of mice

Recently, the ligand for the Mpl receptor (ML) was identified to be thrombopoietin, the principal regulator of megakaryocytopoiesis and thrombopoiesis. We examined the effects of ML, as a single factor or in combinations with early acting factors such as steel factor (SF), interleukin (IL)-3, IL-1, IL-6, and granulocyte colony-stimulating factor (G-CSF), on colony formation from primitive progenitors of mice. Cells enriched for cell cycle dormant primitive progenitors were isolated from bone marrow cells of 5-fluorouracil (5-FU)-treated mice by a combination of Nycodenz density gradient separation, immunomagnetic selection for lineage-negative cells, and fluorescence-activated cell sorter (FACS) sorting for Ly-6A/E+Kit+ cells. ML, in the presence of erythropoietin, could support the formation of only a few megakaryocyte colonies. However, ML acted synergistically with SF or IL-3 to support the formation of multiple types of hematopoietic colonies including multilineage colonies. Effects of the combination of ML and SF on multipotential progenitors were not mediated through other cells, as demonstrated by micromanipulation of individual progenitors. In suspension culture, the combination of ML and SF increased the number of multipotential progenitors. ML also acted synergistically with IL-11, IL-6, or G-CSF to support colony formation in serum-containing, but not in serum-free, cultures. However, the multilineage colony formation seen in serum-containing culture was completely abrogated by addition of ACK2, a neutralizing antibody to Kit protein. Serial observation (mapping studies) of colony development from multipotential progenitors suggested that ML triggers the cell division of dormant progenitors. Based on these observations, we propose that ML can function as an early acting cytokine and stimulate the proliferation of cell cycle dormant progenitors by shortening their G0 period.

Interleukin 3 or interleukin 1 abrogates the reconstituting ability of hematopoietic stem cells

Because of their known myelopoietic activities, both interleukin (IL)-3 and IL-1 are often used in combination with other cytokines for in vitro (ex vivo) expansion of stem cells. We have investigated the effects of IL-3 and IL-1 on in vitro expansion of murine hematopoietic stem cells with long-term engraftment capabilities, using a highly purified progenitor population. Lineage-negative, Ly-6A/E+, c-kit+ bone marrow cells from male mice were cultured in suspension in the presence of stem cell factor, IL-6, IL-11, and erythropoietin with or without IL-3 or IL-1. Kinetic studies revealed an exponential increase in total nucleated cells and about 10-fold enhancement of nucleated cells by IL-3 during the initial 10 days. Addition of IL-3 hastened the development but significantly suppressed the peak production of colony-forming cells. Addition of IL-1 also significantly suppressed the numbers of colony-forming cells. The reconstituting ability of the cultured cells was tested by transplanting the expanded male cells into lethally irradiated female mice. The cells expanded from enriched cells in the absence of IL-3 and IL-1 revealed engraftment at 2, 4, 5, and 6 months, whereas addition of IL-3 or IL-1 to the cultures significantly reduced the reconstituting ability. The results suggest that these cytokines may have a modulatory role on the self-renewal of stem cells and further indicate that the use of IL-3 and IL-1 for in vitro expansion of human stem cells needs to be cautiously evaluated.