P–253 Description of a rare spontaneous monozygotic blastocyst splitting into two discrete euploid blastocysts in vitro detected with time-lapse imaging and preimplantation genetic testing (PGT)

Study question

Can spontaneous and complete blastocyst splitting into two, in vitro, be investigated using time-lapse imaging and biopsy of each trophectoderm, for inference of ploidy?

Summary answer

Time-lapse imaging combined with PGT-A gives insights into the incidence, dynamics and timing of rare blastocyst splitting and the ploidy status of each resulting blastocyst.

What is known already

It is well known that multiple births occur more often with Assisted Reproductive Technologies (ART) than spontaneous conception, even after single embryo transfer. The mechanism of Monozygotic Twinning (MZT) during ART is still unclear but cryopreservation, extended culture, PGT, maternal age and assisted hatching are reported risk factors. MZT is a rare phenomenon, with an incidence of 0.4% in natural conception compared with up to 4.9% in ART. The timing of embryo splitting dictates the type of twinning, in terms of chorionicity and amnionicty, and this is officially determined using ultrasound scanning.

Study design, size, duration

This is a case study describing the detection of the complete splitting of an IVF blastocyst at 140 hours post insemination (hpi), using time-lapse imaging.

The 40-year-old patient previously experienced biochemical pregnancy and several miscarriages; an ectopic molar pregnancy and a probable cornual ectopic. The 39-year-old male partner was normozoospermic.

Participants/materials, setting, methods

Facilitative laser breaching was performed, according to standard operating procedure, of the morula at 96hpi of embryo development, prior to PGT. Images were collected every 10 minutes and developmental events and embryos morphology annotated using the EmbryoScope+™ time lapse incubator and software.

Main results and the role of chance

Over 50,000 hatching blastocysts have been time-lapse imaged, scrutinised and annotated within this group of fertility clinics. This is the first time that such a rare blastocyst splitting event has been recorded and studied.

Following observation of two pronuclei following IVF and typical cleavage development to blastocyst, with facilitative zona breaching on, at 106.7hpi, the full blastocyst’s trophectoderm (TE) began to herniate and hatch. By 114.3hpi a second internal blastocoel cavity formed appearing to divide the inner cell mass (ICM) within the zona pellucida (ZP). This resulting blastocyst proceeded to hatch as its discrete ICM migrated out of the ZP, along with its TE. TE cells from the original blastocyst then began to hatch at 117.5hpi at the same breached site in the ZP with its ICM visibly evacuating the ZP.

By 140hpi the blastocyst had split into two discrete blastocysts while hatching from the ZP. Both resulting blastocysts had clear and separate ICMs and TEs present. Biopsy of approximately 5 cells was performed for each TE, and the blastocysts were vitrified individually. Next Generation Sequencing (NGS) reported both blastocysts to be euploid.

Limitations, reasons for caution

This case may have been detectable without time-lapse imaging, as the splitting was completed prior to biopsy. More expert scrutiny of the images may result in earlier signs of twinning in progress being detected.

Wider implications of the findings: The nature of this detectable in vitro blastocyst splitting, indicates these embryos (if they implanted) to be monozygotic, dichoriol-diamniotic ‘identical’ twins. However – as single embryo transfer is the preferred treatment plan; they may be born years apart. These observations could shed light on the debated models of monozygotic twinning.

Trial registration number

Not applicable

O-083 Non-invasive, label-free optical analysis to detect aneuploidy within the inner cell mass of the preimplantation embryo

Study question

Can we separate between control and reversine-treated cells within the inner cell mass (ICM) of the mouse preimplantation embryo by using label-free and non-invasive hyperspectral microscopy?

Summary answer

Hyperspectral microscopy is able to discern between control and reversine-treated cells using cellular autofluorescence in the complete absence of fluorescence tags.

What is known already

Embryo mosaicism (containing cells that are euploid (46 chromosomes) and aneuploid (deviation from the expected number of chromosomes)) affects up to 17.3% of human blastocyst embryos. Current diagnosis of aneuploidy in the IVF clinic involves a biopsy of trophectoderm (TE) cells or spent media followed by sequencing. In some blastocyst embryos these approaches will fail to diagnose of the proportion of aneuploid cells within the fetal lineage (ICM).

Study design, size, duration

The impact of aneuploidy on cellular metabolism was assessed by using cellular autofluoresence and hyperspectral microscopy (broad spectral profile). Two models were employed: (i) Primary human fibroblast cells with known karyotypes (4-6 independent replicates, euploid n = 467; aneuploid n = 969) and reversine induced aneuploidy in mouse embryos (5-8 independent replicates, 30-44 cells per group). Both models were subjected to hyperspectral imaging to quantify native cell fluorescence.

Participants/materials, setting, methods

The human model is comprised of euploid (male and female) and aneuploid (triploid and trisomies: 13, 18, 21, XXX, and XXY) primary human fibroblast cells. For the mouse model, we treated embryos with reversine, a reversible spindle assembly checkpoint inhibitor, during the 4- to 8-cell division. Individual blastomeres were dissociated from control and reversine treated 8-cell embryos. Blastomeres were either imaged directly or used to generate chimeric blastocysts with differing ratios of control:reversine-treated cells.

Main results and the role of chance

Following unsupervised linear unmixing, the relative abundance of metabolic cofactors was quantified: reduced nicotinamide adenine dinucleotide (NAD(P)H) and flavins with the subsequent calculation of the optical redox ratio (ORR: Flavins/[NAD(P)H + Flavins]). Primary human fibroblast cells displayed an increase in the relative abundance of NAD(P)H with a decrease in flavins, leading to a significant reduction in the ORR for aneuploid cells (P < 0.05). The mouse embryos displayed an identical trend as the human model between control and reversine-treated embryos. Mathematical algorithms were applied and able to distinguish between (i) euploid and aneuploid primary human fibroblast cells, (ii) control and reversine-treated mouse blastomeres and (iii) chimeric blastocysts with differing ratios of control and reversine-treated cells. The accuracy of these separations was supported by receiver operating characteristic curves with areas under the curve. We also showed that hyperspectral imaging of the preimplantation embryo does not impact on embryo developmental competence, pregnancy outcome and offspring health in a mouse model. We believe the role of chance is low as both human somatic cells and mouse embryos showed a consistent shift in cellular metabolism in response to human fibroblast cells that are aneuploid and reversine treated mouse embryos.

Limitations, reasons for caution

Further validation of our approach could include sequencing of the ICM of individual blastocysts to determine the proportion of aneuploid cells in ICM and correlate this with the metabolic profile obtained through hyperspectral imaging.

Wider implications of the findings

With hyperspectral imaging able to discriminate between (i) euploid and aneuploid human fibroblast cells and (ii) control and reversine-treated mouse embryos, this could be an accurate, non-invasive and label-free optical imaging approach to assess mosaicism within the ICM of mouse embryos, potentially leading to a new diagnostic tool for embryos.

Trial registration number

Not applicable

Pressure ulcer healing with an intensive nutrition intervention in an acute setting: a pilot randomised controlled trial

OBJECTIVE

To investigate the feasibility of recruitment, retention, intervention delivery and outcome measurement in a nutritional intervention to promote pressure ulcer healing in an acute setting.

METHOD

Some 50 tertiary hospital patients with stage II or greater pressure ulcer were randomised to receive either individualised nutritional care by a dietitian, including prescription of wound healing supplements; or standard nutritional care. Relevant nutritional and pressure ulcer (PU) parameters were collected at day 5, 10, 15, 22 and then weekly or until discharge.

RESULTS

The median length of hospital stay was 14 days (1-70) with 29 patients discharged by day 15. There were 24 patients discharged before their PU fully healed. Per cent change in valid PU area and score measures from baseline to day 15 were chosen for outcome data analysis to account for varying initial size and severity of the wound and length of stay. There was a larger percentage reduction in PU measures in the intervention group, but this was not statistically significant. Little difference was found in nutritional intake between the control and intervention groups indicating a requirement to focus on effective delivery of the intervention in future studies. Future studies in the acute setting need to account for length of stay and ideally follow patients until full healing.

CONCLUSION

Results indicate a positive association with nutrition intervention and PU healing and that a rigorously designed and adequately powered study is feasible.

An absolute risk-guided approach to cardiovascular risk management within a chest pain clinic: the ARCPAC randomized trial

Background

The majority of patients attending chest pain clinics are found not to have a cardiac cause of their symptoms, but have a high burden of cardiovascular risk factors that may be opportunistically addressed. Absolute risk calculators are recommended to guide risk factor management, although it is uncertain to what extent these calculations may assist with patient engagement in risk factor modification.

Purpose

We sought to determine the usefulness of a proactive, absolute risk-based approach, to guide opportunistic cardiovascular risk factor management within a chest pain clinic.

Methods

This was a prospective, open-label, blinded-endpoint study in 192 enhanced risk (estimated 5-year risk ≥8%, based on Australian Absolute Risk Calculator) patients presenting to a tertiary hospital chest pain clinic. Patients were randomized to best practice usual care, or intervention with development of a proactive cardiovascular risk management strategy framed around a discussion of the individual's absolute risk. Patients found to have a cardiac cause of symptoms were excluded as they constitute a secondary prevention population. Primary outcome was 5-year absolute cardiovascular risk score at minimum 12 months follow up. Secondary outcomes were individual modifiable risk factors (lipid profile, blood pressure, smoking status).

Results

192 people entered the study; 100 in the intervention arm and 92 in usual care. There was no statistical difference between the two groups' baseline sociodemographic and clinical variables. The intervention group showed greater reduction in 5-year absolute risk scores (difference −2.77; p<0.001), and more favourable individual risk factors, although only smoking status and LDL cholesterol reached statistical significance (table).

Conclusion

An absolute risk-guided proactive risk factor management strategy employed opportunistically in a chest pain clinic significantly improves 5-year cardiovascular risk scores.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Tasmanian Community Fund

Development of comparable algorithms to measure primary care indicators using administrative health data across three Canadian provinces

INTRODUCTION

Performance measurement has been recognized as key to transforming primary care (PC). Yet, performance reporting in PC lags behind even though high-performing PC is foundational to an effective and efficient health care system.

OBJECTIVES

We used administrative data from three Canadian provinces, British Columbia, Ontario and Nova Scotia, to: 1) identify and develop a core set of PC performance indicators using administrative data and 2) examine their ability to capture PC performance.

METHODS

Administrative data used included Physician Billings, Discharge Abstract Database, the National Ambulatory Care and Reporting System database, Census and Vital Statistics. Indicators were compiled based on a literature review of PC indicators previously developed with administrative data available in Canada (n=158). We engaged in iterative discussions to assess data conformity, completeness, and plausibility of results in all jurisdictions. Challenges to creating comparable algorithms were examined through content analysis and research team discussions, which included clinicians, analysts, and health services researchers familiar with PC.

RESULTS

Our final list included 21 PC performance indicators pertaining to 1) technical care (n=4), 2) continuity of care (n=6), and 3) health services utilization (n=11). Establishing comparable algorithms across provinces was possible though time intensive. A major challenge was inconsistent data elements. Ease of data access, and a deep understanding of the data and practice context, was essential for selecting the most appropriate data elements.

CONCLUSIONS

This project is unique in creating algorithms to measure PC performance across provinces. It was essential to balance internal validity of the indicators within a province and external validity across provinces. The intuitive desire of having the exact same coding across provinces was infeasible due to lack of standardized PC data. Rather, a context-tailored definition was developed for each jurisdiction. This work serves as an example for developing comparable PC performance indicators across different provincial/territorial jurisdictions.

OP0187 DETERMINING OPTIMAL COOLING AND ADMINISTRATION METHODS FOR CNTX-4975 INTRA-ARTICULAR INJECTION IN SUBJECTS WITH MODERATE TO SEVERE OSTEOARTHRITIS KNEE PAIN

Background:

CNTX-4975 is a highly purified, synthetic capsaicin being developed to provide long-term analgesia after a single intra-articular (IA) injection for patients with moderate to severe osteoarthritis (OA) knee pain. CNTX-4975 IA administration is associated with short-term post-procedural pain that can be attenuated with preemptive joint cooling.

Objectives:

To evaluate cooling and administration procedures for CNTX-4975 IA injection, with goals of balancing patient comfort and ease of use and assessing clinical response 8 weeks after injection.

Methods:

This phase 3, open-label, 8-week study (NCT03661996) enrolled subjects aged 40–95 y with Kellgren-Lawrence grade 1–4, BMI ≤45 kg/m2, and stable, moderate to severe OA knee pain and who failed ≥2 therapies. Subjects were assigned to unilateral/bilateral CNTX-4975 1 mg IA injections as determined by OA pain/joint replacement status, then randomized by study site to 1 of 5 treatment regimens (Figure). The primary outcome measure assessed Breg cooling control vs other cooling regimens on day 1 using a combined sum of 1) pain (0, none; 4, severe) 30 minutes after CNTX-4975 injection; 2) subject satisfaction (SS) with cooling/injection procedures; and 3) investigator satisfaction (IS) with procedures. SS and IS were measured on a 1–7 scale (1, completely dissatisfied; 7, completely satisfied); pain was reverse scored and normalized (1, severe; 7, none) for equal weighting. Geometric mean ratios (GMR) with 95% CIs were constructed for each regimen vs Breg control (ANCOVA); lower 95% CI >0.7 was considered clinically acceptable. Secondary endpoints included percentage of subjects by subject type meeting criteria for Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responders 8 weeks after injection. Safety assessments included TEAEs.

Results:

The intent-to-treat population included 848 subjects. The primary combined outcome showed that all cooling and administration regimens were clinically acceptable, with the evaluated cold gel wraps being at least as effective as the Breg circulating ice-water wrap (Table). For subjects with unilateral OA, OMERACT-OARSI response rates were 67% in those with no/mild nonindex knee pain and 81% in those with nonindex knee single joint replacement. For subjects with bilateral knee OA receiving bilateral injections, response rates for index and nonindex knees were 73% and 79%. TEAEs were reported in 22% of subjects; <1% were serious. TEAEs occurring in >2% of subjects were procedural pain (2.9%), arthralgia (2.2%), and nausea (2.1%), with no meaningful differences across groups.

Conclusion:

All cooling regimens for CNTX-4975 IA administration were clinically acceptable and well tolerated, offering feasible options for use in routine practice. Importantly, high levels of clinical response were observed 8 weeks after unilateral or bilateral knee injections for moderate to severe OA knee pain.

Primary Combined Endpoint Outcome in the Index Knee, Normalized Scale, by Cooling and Administration Procedure (ANCOVA Model)

Breg Cooling ControlN=162Gel Pack CoolingN=179Shortened Gel Pack CoolingN=175Single Needle Injection,Gel Pack Cooling,2% LidocaineN=160Single Needle Injection,Gel Pack Cooling,1% LidocaineN=172Mean (SD)17.23 (2.660)18.23 (2.023)16.81 (2.891)17.57 (3.049)16.43 (3.138)Geometric LS Mean (SE)17.18 (1.016)18.26 (1.015)16.48 (1.016)17.40 (1.016)16.00 (1.015)95% CI16.66, 17.7217.74, 18.8015.99, 16.9916.87, 17.9515.53, 16.49Comparison vs Breg CoolingGMR (SE)1.06 (1.022)0.96 (1.022)1.01 (1.022)0.93 (1.022)95% CI1.02, 1.110.92, 1.000.97, 1.060.89, 0.97Clinically Acceptable?YesYesYesYes

LS, least squares; SD, standard deviation; SE, standard error.

GMR lower 95% CI >0.7 considered clinically equivalent.

Disclosure of Interests:

Randall Stevens Shareholder of: Centrexion Therapeutics Corp, Employee of: Centrexion Therapeutics Corp, Peter Hanson Shareholder of: Centrexion Therapeutics Corp, Employee of: Centrexion Therapeutics Corp, Paul Tiseo Employee of: Centrexion Therapeutics Corp, Kimberly Guedes Shareholder of: Centrexion Therapeutics Corp, Employee of: Centrexion Therapeutics Corp, James Campbell Shareholder of: Centrexion Therapeutics Corp, Employee of: Centrexion Therapeutics Corp, James Connolly Employee of: Centrexion Therapeutics Corp, Stephanie Ruggiero Employee of: Centrexion Therapeutics Corp, Meg Corliss Employee of: Centrexion Therapeutics Corp, Valerie Smith Consultant of: Centrexion Therapeutics Corp, Philip G Conaghan Consultant of: AbbVie, BMS, Eli Lilly, EMD Serono, Flexion Therapeutics, Galapagos, GSK, Novartis, Pfizer, Speakers bureau: AbbVie, Eli Lilly, Novartis, Pfizer

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.