The human urine metabolome

Urine has long been a "favored" biofluid among metabolomics researchers. It is sterile, easy-to-obtain in large volumes, largely free from interfering proteins or lipids and chemically complex. However, this chemical complexity has also made urine a particularly difficult substrate to fully understand. As a biological waste material, urine typically contains metabolic breakdown products from a wide range of foods, drinks, drugs, environmental contaminants, endogenous waste metabolites and bacterial by-products. Many of these compounds are poorly characterized and poorly understood. In an effort to improve our understanding of this biofluid we have undertaken a comprehensive, quantitative, metabolome-wide characterization of human urine. This involved both computer-aided literature mining and comprehensive, quantitative experimental assessment/validation. The experimental portion employed NMR spectroscopy, gas chromatography mass spectrometry (GC-MS), direct flow injection mass spectrometry (DFI/LC-MS/MS), inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) experiments performed on multiple human urine samples. This multi-platform metabolomic analysis allowed us to identify 445 and quantify 378 unique urine metabolites or metabolite species. The different analytical platforms were able to identify (quantify) a total of: 209 (209) by NMR, 179 (85) by GC-MS, 127 (127) by DFI/LC-MS/MS, 40 (40) by ICP-MS and 10 (10) by HPLC. Our use of multiple metabolomics platforms and technologies allowed us to identify several previously unknown urine metabolites and to substantially enhance the level of metabolome coverage. It also allowed us to critically assess the relative strengths and weaknesses of different platforms or technologies. The literature review led to the identification and annotation of another 2206 urinary compounds and was used to help guide the subsequent experimental studies. An online database containing the complete set of 2651 confirmed human urine metabolite species, their structures (3079 in total), concentrations, related literature references and links to their known disease associations are freely available at http://www.urinemetabolome.ca.

SMPDB 2.0: big improvements to the Small Molecule Pathway Database

The Small Molecule Pathway Database (SMPDB, http://www.smpdb.ca) is a comprehensive, colorful, fully searchable and highly interactive database for visualizing human metabolic, drug action, drug metabolism, physiological activity and metabolic disease pathways. SMPDB contains >600 pathways with nearly 75% of its pathways not found in any other database. All SMPDB pathway diagrams are extensively hyperlinked and include detailed information on the relevant tissues, organs, organelles, subcellular compartments, protein cofactors, protein locations, metabolite locations, chemical structures and protein quaternary structures. Since its last release in 2010, SMPDB has undergone substantial upgrades and significant expansion. In particular, the total number of pathways in SMPDB has grown by >70%. Additionally, every previously entered pathway has been completely redrawn, standardized, corrected, updated and enhanced with additional molecular or cellular information. Many SMPDB pathways now include transporter proteins as well as much more physiological, tissue, target organ and reaction compartment data. Thanks to the development of a standardized pathway drawing tool (called PathWhiz) all SMPDB pathways are now much more easily drawn and far more rapidly updated. PathWhiz has also allowed all SMPDB pathways to be saved in a BioPAX format. Significant improvements to SMPDB’s visualization interface now make the browsing, selection, recoloring and zooming of pathways far easier and far more intuitive. Because of its utility and breadth of coverage, SMPDB is now integrated into several other databases including HMDB and DrugBank.

Complement Protein C1q Enhances Macrophage Foam Cell Survival and Efferocytosis

In the atherosclerotic lesion, macrophages ingest high levels of damaged modified low-density lipoproteins (LDLs), generating macrophage foam cells. Foam cells undergo apoptosis and, if not efficiently cleared by efferocytosis, can undergo secondary necrosis, leading to plaque instability and rupture. As a component of the innate immune complement cascade, C1q recognizes and opsonizes modified forms of LDL, such as oxidized or acetylated LDL, and promotes ingestion by macrophages in vitro. C1q was shown to be protective in an atherosclerosis model in vivo. Therefore, this study aimed to investigate whether ingestion of modified LDL in the presence of C1q alters macrophage foam cell survival or function. In an unbiased transcriptome analysis, C1q was shown to modulate expression of clusters of genes involved in cell death and apoptosis pathways in human monocyte-derived macrophages ingesting modified LDL; this was validated by quantitative PCR in human and murine macrophages. C1q downregulated levels and activity of active caspase-3 and PARP-1 in human and mouse macrophages during ingestion of modified LDL. This led to a measurable increase in survival and decrease in cell death, as measured by alamarBlue and propidium iodide assays, respectively. C1q opsonization also increased phagocytosis and efferocytosis in macrophage foam cells. These data suggest that C1q promotes macrophage survival during ingestion of excess cholesterol, as well as improves foam cell efferocytic function. This may be important in slowing disease progression and provides insight into the protective role of C1q in early atherosclerosis.

Characterizing workplace exposures in Vietnamese women working in California nail salons

OBJECTIVES

We engaged Vietnamese nail salon workers in a community-based participatory research (CBPR) study to measure personal and area concentrations of solvents in their workplace.

METHODS

We measured average work-shift concentrations of toluene, ethyl acetate, and isopropyl acetate among 80 workers from 20 salons using personal air monitors. We also collected area samples from 3 salons using summa canisters.

RESULTS

For personal measurements, the arithmetic mean was 0.53 parts per million (range = 0.02-5.50) for ethyl acetate, 0.04 parts per million (range = 0.02-0.15) for isopropyl acetate, and 0.15 parts per million (range = 0.02-1.0) for toluene. Area measurements were lower in comparison, but we detected notable levels of methyl methacrylate, a compound long banned from nail products. Predictors of solvent levels included different forms of ventilation and whether the salon was located in an enclosed building.

CONCLUSIONS

Using a CBPR approach that engaged community members in the research process contributed to the successful recruitment of salon workers. Measured levels of toluene, methyl methacrylate, and total volatile organic compounds were higher than recommended guidelines to prevent health symptoms such as headaches, irritations, and breathing problems, which were frequently reported in this workforce.

History of chronic comorbidity and risk of chemotherapy-induced febrile neutropenia in cancer patients not receiving G-CSF prophylaxis

BACKGROUND

Chemotherapy-induced febrile neutropenia (FN) is a clinically important complication that affects patient outcome by delaying chemotherapy doses or reducing dose intensity. Risk of FN depends on chemotherapy- and patient-level factors. We sought to determine the effects of chronic comorbidities on risk of FN.

DESIGN

We conducted a cohort study to examine the association between a variety of chronic comorbidities and risk of FN in patients diagnosed with six types of cancer (non-Hodgkin lymphoma and breast, colorectal, lung, ovary, and gastric cancer) from 2000 to 2009 who were treated with chemotherapy at Kaiser Permanente Southern California, a large managed care organization. We excluded those patients who received primary prophylactic granulocyte colony-stimulating factor. History of comorbidities and FN events were identified using electronic medical records. Cox models adjusting for propensity score, stratified by cancer type, were used to determine the association between comorbid conditions and FN. Models that additionally adjusted for cancer stage, baseline neutrophil count, chemotherapy regimen, and dose reduction were also evaluated.

RESULTS

A total of 19 160 patients with mean age of 60 years were included; 963 (5.0%) developed FN in the first chemotherapy cycle. Chronic obstructive pulmonary disease [hazard ratio (HR) = 1.30 (1.07-1.57)], congestive heart failure [HR = 1.43 (1.00-1.98)], HIV infection [HR = 3.40 (1.90-5.63)], autoimmune disease [HR = 2.01 (1.10-3.33)], peptic ulcer disease [HR = 1.57 (1.05-2.26)], renal disease [HR = 1.60 (1.21-2.09)], and thyroid disorder [HR = 1.32 (1.06-1.64)] were all associated with a significantly increased FN risk.

CONCLUSIONS

These results provide evidence that history of several chronic comorbidities increases risk of FN, which should be considered when managing patients during chemotherapy.

Speech recognition for clinical documentation from 1990 to 2018: a systematic review

OBJECTIVE

The study sought to review recent literature regarding use of speech recognition (SR) technology for clinical documentation and to understand the impact of SR on document accuracy, provider efficiency, institutional cost, and more.

MATERIALS AND METHODS

We searched 10 scientific and medical literature databases to find articles about clinician use of SR for documentation published between January 1, 1990, and October 15, 2018. We annotated included articles with their research topic(s), medical domain(s), and SR system(s) evaluated and analyzed the results.

RESULTS

One hundred twenty-two articles were included. Forty-eight (39.3%) involved the radiology department exclusively and 10 (8.2%) involved emergency medicine; 10 (8.2%) mentioned multiple departments. Forty-eight (39.3%) articles studied productivity; 20 (16.4%) studied the effect of SR on documentation time, with mixed findings. Decreased turnaround time was reported in all 19 (15.6%) studies in which it was evaluated. Twenty-nine (23.8%) studies conducted error analyses, though various evaluation metrics were used. Reported percentage of documents with errors ranged from 4.8% to 71%; reported word error rates ranged from 7.4% to 38.7%. Seven (5.7%) studies assessed documentation-associated costs; 5 reported decreases and 2 reported increases. Many studies (44.3%) used products by Nuance Communications. Other vendors included IBM (9.0%) and Philips (6.6%); 7 (5.7%) used self-developed systems.

CONCLUSION

Despite widespread use of SR for clinical documentation, research on this topic remains largely heterogeneous, often using different evaluation metrics with mixed findings. Further, that SR-assisted documentation has become increasingly common in clinical settings beyond radiology warrants further investigation of its use and effectiveness in these settings.

Activation of μ opioid receptors modulates inflammation in acute experimental colitis

BACKGROUND

μ opioid receptors (μORs) are expressed by neurons and inflammatory cells, and mediate immune response. We tested whether activation of peripheral μORs ameliorates the acute and delayed phase of colitis.

METHODS

C57BL/6J mice were treated with 3% dextran sodium sulfate (DSS) in water, 5 days with or without the peripherally acting μOR agonist, [D-Ala2, N-Me-Phe4, Gly5-ol]-Enkephalin (DAMGO) or with DAMGO+μOR antagonist at day 2-5, then euthanized. Other mice received DSS followed by water for 4 weeks, or DSS with DAMGO starting at day 2 of DSS for 2 or 3 weeks followed by water, then euthanized at 4 weeks. Disease activity index (DAI), histological damage, and myeloperoxidase assay (MPO), as index of neutrophil infiltration, were evaluated. Cytokines and μOR mRNAs were measured with RT-PCR, and nuclear factor-kB (NF-kB), the antiapoptotic factor Bcl-xL, and caspase 3 and 7 with Western blot.

KEY RESULTS

DSS induced acute colitis with elevated DAI, tissue damage, apoptosis and increased MPO, cytokines, μOR mRNA, and NF-kB. DAMGO significantly reduced DAI, inflammatory indexes, cytokines, caspases, and NF-kB, and upregulated Bcl-xL, effects prevented by μOR antagonist. In DSS mice plus 4 weeks of water, DAI, NF-kB, and μOR were normal, whereas MPO, histological damage, and cytokines were still elevated; DAMGO did not reduce inflammation, and did not upregulate Bcl-xL.

CONCLUSIONS & INFERENCES

μOR activation ameliorated the acute but not the delayed phase of DSS colitis by reducing cytokines, likely through activation of the antiapoptotic factor, Bcl-xL, and suppression of NF-kB, a potentiator of inflammation.

Sacrifice and solidarity: a qualitative study of family experiences of death and bereavement in critical care settings during the pandemic

BACKGROUND

Pandemic-related restrictions are expected to continue to shape end-of-life care and impact the experiences of dying hospitalised patients and their families.

OBJECTIVE

To understand families' experiences of loss and bereavement during and after the death of their loved one amidst the SARS-CoV-2 (COVID-19) pandemic.

DESIGN

Qualitative descriptive study.

SETTING

Three acute care units in a Canadian tertiary care hospital.

PARTICIPANTS

Family members of 28 hospitalised patients who died from March-July 2020.

MAIN OUTCOME MEASURES

Qualitative semistructured interviews conducted 6-16 months after patient death inquired about family experiences before and beyond the death of their loved one and garnered suggestions to improve end-of-life care.

RESULTS

Pandemic restrictions had consequences for families of dying hospitalised patients. Most family members described an attitude of acquiescence, some framing their experience as a sacrifice made for the public good. Families appreciated how clinicians engendered trust in the name of social solidarity while trying to mitigate the negative impact of family separation. However, fears about the patient's experience of isolation and changes to postmortem rituals also created despair and contributed to long-lasting grief.

CONCLUSION

Profound loss and enduring grief were described by family members whose final connections to their loved one were constrained by pandemic circumstances. Families observed solidarity among clinical staff and experienced a sense of unity with staff, which alleviated some distress. Their suggestions to improve end-of-life care given pandemic restrictions included frequent, flexible communication, exceptions for family presence when safe, and targeted efforts to connect patients whose isolation is intensified by functional impairment or limited technological access.

TRIAL REGISTRATION NUMBER

NCT04602520; Results.

The role of the non-conserved residue at position 104 of class A beta-lactamases in susceptibility to mechanism-based inhibitors

The role of the non-conserved amino acid residue at position 104 of the class A beta-lactamases, which comprises a highly conserved sequence of amino acids at the active sites of these enzymes, in both the hydrolysis of beta-lactam substrates and inactivation by mechanism-based inhibitors was investigated. Site-directed mutagenesis was performed on the penPC gene encoding the Bacillus cereus 569/H beta-lactamase I to replace Asp104 with the corresponding Staphylococcus aureus PC1 residue Ala104. Kinetic data obtained with the purified Asp104Ala B. cereus 569/H beta-lactamase I was compared to that obtained from the wild-type B. cereus and S. aureus enzymes. Replacement of amino acid residue 104 had little effect on the Michaelis parameters for the hydrolysis of both S- and A-type penicillins. Relative to wild-type enzyme, the Asp104Ala beta-lactamase I had 2-fold higher Km values for benzylpenicillin and methicillin, but negligible difference in Km for ampicillin and oxacillin. However, kcat values were also slightly increased resulting in little change in catalytic efficiency, kcat/Km. In contrast, the Asp104Ala beta-lactamase I became more like the S. aureus enzyme in its response to the mechanism-based inhibitors clavulanic acid and 6-beta-(trifluoromethane sulfonyl)amido-penicillanic acid sulfone with respect to both response to the inhibitors and subsequent enzymatic properties. Based on the known three-dimensional structures of the Bacillus licheniformis 749/C, Escherichia coli TEM and S. aureus PC1 beta-lactamases, a model for the role of the non-conserved residue at position 104 in the process of inactivation by mechanism-based inhibitors is proposed.

Coronavirus Disease Contact Tracing Outcomes and Cost, Salt Lake County, Utah, USA, March-May 2020

Outcomes and costs of coronavirus disease (COVID-19) contact tracing are limited. During March–May 2020, we constructed transmission chains from 184 index cases and 1,499 contacts in Salt Lake County, Utah, USA, to assess outcomes and estimate staff time and salaries. We estimated 1,102 staff hours and $29,234 spent investigating index cases and contacts. Among contacts, 374 (25%) had COVID-19; secondary case detection rate was ≈31% among first-generation contacts, ≈16% among second- and third-generation contacts, and ≈12% among fourth-, fifth-, and sixth-generation contacts. At initial interview, 51% (187/370) of contacts were COVID-19–positive; 35% (98/277) became positive during 14-day quarantine. Median time from symptom onset to investigation was 7 days for index cases and 4 days for first-generation contacts. Contact tracing reduced the number of cases between contact generations and time between symptom onset and investigation but required substantial resources. Our findings can help jurisdictions allocate resources for contact tracing.

Synchronizing single-shot high-energy iodine photodissociation laser PALS and high-repetition-rate femtosecond Ti:sapphire laser system

A system of precise pulse synchronization between a single-shot large-scale laser exploiting an acousto-optical modulator and a femtosecond high repetition rate laser is reported in this article. This opto-electronical system has been developed for synchronization of the sub-nanosecond kJ-class iodine photodissociation laser system (Prague Asterix Laser System-PALS) with the femtosecond 25-TW Ti:sapphire (Ti:Sa) laser operating at a repetition rate 1 kHz or 10 Hz depending on the required energy level of output pulses. At 1 kHz synchronization regime, a single femtosecond pulse of duration about 45 fs and a small energy less than 1 mJ are exploited as a probe beam for irradiation of a three-frame interferometer, while at 10 Hz repetition rate a single femtosecond pulse with higher energy about 7-10 mJ is exploited as a probe beam for irradiation of a two-channel polaro-interferometer. The synchronization accuracy ±100 ps between the PALS and the Ti:Sa laser pulses has been achieved in both regimes of synchronization. The femtosecond interferograms of laser-produced plasmas obtained by the three-frame interferometer and the femtosecond polarimetric images obtained by the two-frame polaro-interferometer confirm the full usefulness and correct functionality of the proposed method of synchronization.

Characterizing Hypertension Specialist Care in Canada: A National Survey

Background

The hypertension specialist often receives referrals of patients with young-onset, severe, difficult-to-control hypertension, patients with hypertensive emergencies, and patients with secondary causes of hypertension. Specialist hypertension care compliments primary care for these complex patients and contributes to an overall hypertension control strategy. The objective of this study was to characterize hypertension centres and the practice patterns of Canadian hypertension specialists.

Methods

Adult hypertension specialists across Canada were surveyed to describe hypertension centres and specialist practice in Canada, including the following: the patient population managed by hypertension specialists; details on how care is provided; practice pattern variations; and differences in access to specialized hypertension resources across the country.

Results

The survey response rate was 73.5% from 25 hypertension centres. Most respondents were nephrologists and general internal medicine specialists. Hypertension centres saw between 50 and 2500 patients yearly. A mean of 17% (± 15%) of patients were referred from the emergency department and a mean of 52% (± 24%) were referred from primary care. Most centres had access to specialized testing (adrenal vein sampling, level 1 sleep studies, autonomic testing) and advanced therapies for resistant hypertension (renal denervation). Considerable heterogeneity was present in the target blood pressure in young people with low cardiovascular risk and in the diagnostic algorithms for investigating secondary causes of hypertension.

Conclusions

These results summarize the current state of hypertension specialist care and highlight opportunities for further collaboration among hypertension specialists, including standardization of the approach to specialist care for patients with hypertension.

Abstract P5-10-03: XRAYS (eXamining Relevance of Articles to Young Survivors) program survey of information needs and media use by young breast cancer survivors and young women at high risk for breast cancer

Women age 45 or under with breast cancer, or who are at high risk for breast cancer, have distinct health risks and needs when compared to their older counterparts. Young women with breast cancer or at high risk for breast cancer need evidence-based, high-quality information to help them make informed decisions about their specific health needs. Interpreting media reports on research findings, including determining the study implications for younger women is often challenging. To help women better understand media coverage of new research, Facing Our Risk of Cancer Empowered (FORCE) developed the CDC-funded XRAYS (eXamining Relevance of Articles to Young Survivors) program. To assure that the XRAYS program is responsive to the community's needs, FORCE launched a survey to assess where young women turn for information about breast cancer and to identify their information needs. The survey examines: how frequently women visit various media sources and health- or cancer-related websites for information on breast cancer screening, treatment, surgery, prevention, genetics, or survivorship; how much the women trust these information sources; whether they have ever tried to share media articles with their health care team and how the team received the information; and at what point(s) during the process of screening, diagnosis, treatment, survivorship and/or risk management respondents actively seek out information from the media. FORCE launched the survey nationally through its network of 50 outreach groups, partner organizations that serve young breast cancer survivors, and via a social media campaign targeting women age 45 and under with, or at high risk for breast cancer. The survey was open March 15 - June 30, 2015. We will report results from over 800 women, age 45 or younger, including those with breast cancer, who have previously had breast cancer, or who are at high risk for breast cancer. Analysis will determine response frequencies and whether information needs and utilization correlate with key demographic variables such as race/ethnicity, education, and income level. We will use correlation and multiple regression analysis to assess patterns in the types of information needed and channels where information is sought. These results will ensure XRAYS materials and dissemination efforts are efficient and responsive to the young breast cancer population's needs, and will inform the broader medical, media and patient advocacy communities about the distinct information needs of this group.

Citation Format: Rezende LF, Huynh J, Kramer K, Cranmer M, Schlager L, Pugh-Yi R, Friedman S. XRAYS (eXamining Relevance of Articles to Young Survivors) program survey of information needs and media use by young breast cancer survivors and young women at high risk for breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-10-03.

Prevalence of gestational diabetes mellitus among Swampy Cree women in Moose Factory, James Bay

BACKGROUND

Although high rates of gestational diabetes mellitus have been documented in native populations, few studies have examined rates of the disease among native Indians in Canada. The authors conducted a study to estimate the prevalence of gestational diabetes among Swampy Cree women, to identify factors predictive of the occurrence of gestational diabetes, and to identify delivery and infant outcomes related to the presence of the disease.

METHODS

Information on Swampy Cree women who gave birth at Weeneebayko Hospital, Moose Factory, James Bay, Ont., between 1987 and 1995 was obtained from medical charts. Patients with and without gestational diabetes were compared. Logistic regression analysis was used to identify independent predictors of gestational diabetes. Delivery and infant outcomes that occurred secondary to gestational diabetes were also identified by means of logistic regression.

RESULTS

A total of 1401 deliveries occurred at Weeneebayko Hospital over the study period, of which 1298 were included in the study. Gestational diabetes was diagnosed in 110 (8.5% [95% confidence interval (CI) 6.9%-9.9%]) of the 1298 pregnancies. Factors predictive of gestational diabetes were age 35 years or more (relative risk [RR] 4.1, 95% CI 1.5-11.7), a history of gestational diabetes in a previous pregnancy (RR 6.4, 95% CI 3.5-11.7), diastolic blood pressure of 80 mm Hg or higher at the first prenatal visit (RR 1.7, 95% CI 1.1-2.8), weight greater than 80 kg at the first prenatal visit (RR 4.9, 95% CI 1.8-12.9) and having a first-degree relative with diabetes (RR 3.0, 95% CI 1.4-6.1). The only delivery outcome independently associated with the presence of gestational diabetes was an increased likelihood of needing assisted delivery (forceps or vacuum extraction) (RR 2.8, 95% CI 1.1-7.0). Shoulder dystocia was indirectly associated with gestational diabetes owing to increased infant birth weight. Infant outcomes associated with the presence of gestational diabetes were birth weight greater than 4500 g (RR 2.4, 95% CI 1.4-3.8), hyperbilirubinemia (RR 2.9, 95% CI 1.4-6.1), hypoglycemia (RR 7.3, 95% CI 3.7-14.4) and hypocalcemia (RR 8.9, 95% CI 2.3-33.7).

INTERPRETATION

Gestational diabetes occurred in a significant minority of Swampy Cree women and was associated with a number of adverse outcomes.

The Green Maternity project: A midwife-led initiative to promote correct waste segregation on an Australian postnatal ward

AIMS

Healthcare waste production is a significant contributor to carbon emissions, negatively impacting the environment. Ineffective healthcare waste disposal results in greater measures to manage it which is costly to both the environment and healthcare organizations. This study aimed to improve waste management in a tertiary maternity hospital. Specifically, the impact of a midwife-led intervention to improve waste segregation, staff knowledge and attitudes and waste management-related costs was investigated.

DESIGN

A multi-method study including pre- and post-intervention staff waste management knowledge and attitude surveys and waste audits of bins located on the postnatal ward.

METHODS

The intervention included education sessions, posters and signage by waste bins and monthly newsletters distributed throughout 2021 to raise staff awareness of correct waste segregation processes. Pre- and post-intervention surveys were distributed in early 2021 and early 2022, respectively. The waste audits occurred on three occasions, January, July and December of 2021. The waste audit included total waste in kilograms (kg), waste in kg by segregation and identification of correct and incorrect segregation. Waste audit and quantitative staff survey data were analysed using descriptive statistics and chi square. Qualitative data from the staff surveys were analysed using content analysis.

RESULTS

Knowledge and attitudes to waste management were similar across pre- and post-intervention staff surveys. Knowledge of accurate allocation of specific items to waste streams was variable with errors identified in both the pre- and post-surveys. Waste audit data showed reductions in clinical waste at each measurement, with a 71.2% decrease in clinical waste from baseline to the final audit. Accuracy of waste segregation also improved from the baseline to final audit, resulting in a 48% reduction in waste management costs.

CONCLUSION

The midwife-led initiative improved waste segregation and achieved the associated waste management cost reduction.

IMPACT

A midwifery-led initiative to address waste production and segregation on a maternity ward had a positive impact on waste segregation practices and associated waste management costs. The existence of change champions along with in-service sessions, posters and newsletters to raise awareness of correct waste segregation resulted in a 71% reduction of incorrect items being placed in clinical waste bins. Challenges such as COVID-19 pressures and workload made it difficult for midwives to engage in waste management education and effective waste segregation.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution. WHAT DOES THIS PAPER CONTRIBUTE TO THE WIDER GLOBAL CLINICAL COMMUNITY?: Implementing clinician-led waste management interventions across hospital wards while addressing workload issues are likely to have significant cost benefits for organisations and minimise the environmental impacts of healthcare settings.

Persistent left cranial vena cava and right cranial vena cava aplasia in a French bulldog and a Cavalier King Charles spaniel with severe pulmonic stenosis

One French bulldog and one Cavalier King Charles spaniel were referred for pulmonary balloon valvuloplasty (PBV) after being diagnosed with severe pulmonic stenosis. In both patients, a dilated coronary sinus was noted on transthoracic echocardiography, suggesting persistent left cranial vena cava. Despite complete preoperative workup being performed, persistent left cranial vena cava with right cranial vena cava aplasia was not identified until after right jugular catheterization. This case study highlights vascular anomalies that hinder traditional approaches to PBV and diagnostic considerations for preoperative workup as recognition of these venous anomalies would have changed the approach to catheterization for PBV, minimizing the risk for complications, saving resources, and decreasing anesthetic time in these patients.