Efficacy of detergent-based cleaning and wiping against SARS-CoV-2 on high-touch surfaces

Efficacy of cleaning methods against SARS-CoV-2 suspended in either 5% soil load (SARS-soil) or simulated saliva (SARS-SS) was evaluated immediately (hydrated virus, T0) or 2 hours post-contamination (dried virus, T2). Hard water dampened wiping (DW) of surfaces, resulted in 1.77-3.91 log reduction (T0) or 0.93-2.41 log reduction (T2). Incorporating surface pre-wetting by spraying with a detergent solution (D + DW) or hard water (W + DW) just prior to dampened wiping did not unilaterally increase efficacy against infectious SARS-CoV-2, however, the effect was nuanced with respect to surface, viral matrix, and time. Cleaning efficacy on porous surfaces (seat fabric, SF) was low. W + DW on stainless steel (SS) was as effective as D + DW for all conditions except SARS-soil at T2 on SS. DW was the only method that consistently resulted in > 3-log reduction of hydrated (T0) SARS-CoV-2 on SS and ABS plastic. These results suggest that wiping with a hard water dampened wipe can reduce infectious virus on hard non-porous surfaces. Pre-wetting surfaces with surfactants did not significantly increase efficacy for the conditions tested. Surface material, presence or absence of pre-wetting, and time post-contamination affect efficacy of cleaning methods.

Evaluation of surface disinfection methods to inactivate the beta coronavirus Murine Hepatitis Virus

The list of EPA-approved disinfectants for coronavirus features many products for use on hard, non-porous materials. There are significantly fewer products registered for use on porous materials. Further, many common, high-touch surfaces fall in between non-porous materials such as glass and porous materials such as soft fabrics. The objective of this study was to assess the efficacy of selected commercially available disinfectant products against coronaviruses on common, high-touch surfaces. Four disinfectants (Clorox Total 360, Bleach solution, Vital Oxide, and Peroxide Multi-Surface Cleaner) were evaluated against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV in cell culture medium was inoculated onto four materials: stainless steel, latex-painted drywall tape, Styrene Butadiene rubber (rubber), and bus seat fabric. Immediately (T0) or 2-hr (T2) post-inoculation, disinfectants were applied by trigger-pull or electrostatic sprayer and either held for recommended contact times (Spray only) or immediately wiped (Spray and Wipe). Recovered infectious MHV was quantified by median tissue culture infectious dose assay. Bleach solution, Clorox Total 360, and Vital Oxide were all effective (>3-log₁₀ reduction or complete kill of infectious virus) with both the Spray Only and Spray and Wipe methods on stainless steel, rubber, and painted drywall tape when used at recommended contact times at both T0 and T2 hr. Multi-Surface Cleaner unexpectedly showed limited efficacy against MHV on stainless steel within the recommended contact time; however, it showed increased (2.3 times greater efficacy) when used in the Spray and Wipe method compared to Spray Only. The only products to achieve a 3-log₁₀ reduction on fabric were Vital Oxide and Clorox Total 360; however, the efficacy of Vital Oxide against MHV on fabric was reduced to below 3-log₁₀ when applied by an electrostatic sprayer compared to a trigger-pull sprayer. This study highlights the importance of considering the material, product, and application method when developing a disinfection strategy for coronaviruses on high-touch surfaces.

A139 EQUITY IN ACCESS TO COLORECTAL CANCER SCREENING IN NOVA SCOTIA

Background

Population-based colorectal cancer (CRC) screening programs aim to minimize inequities in participation through universal access, however, there remain disparities associated with low education, socio-economic status, and population centre. In the United States racialized groups have lower screening participation, and Black and Indigenous adults have higher CRC mortality. There is no Canadian data on racialized group participation in CRC screening because racial and ethnic data is not routinely collected. The Nova Scotia Colon Cancer Prevention Program (NSCCPP) mails fecal immunochemical tests (FIT) biennially to all residents aged 50–74 and allows for optional self-identified race and ethnicity.

Aims

To determine whether participation rates in the NSCCPP differ on the basis of race/ethnicity, age, sex, or population centre. In this preliminary analysis we report screening participation on the basis of race/ethnicity.

Methods

A retrospective cohort study was performed using the NSCCPP database to identify screen-eligible adults who returned a FIT to the program (i.e. participated) from 2011 to 2021. Racialized groups were identified based on self-identification form results allowing for multiple category selections. Race/Ethnicity was categorized as White, Black/African Canadian, Indigenous, Asian, Middle Eastern. The 2016 Canadian census was used to estimate the screen-eligible population (age 50–74) and race/ethnicity group population sizes. Unique participants were identified as individuals who returned one or more FITs in the study period. Unique participants were compared to the screen-eligible population to estimate participation over the 10-year study period.

Results

508,533 FITs were returned over 10 years by 208,702 unique participants. The number of annual FITs returned ranged from 14,066 in 2011 to 65,746 in 2019. Participants were 56% female, 44% male, with a mean age 62.8 (± 7.0). FIT status was 89% negative, 7% positive, and 4% indeterminate. 96% (n=490,398) of participants provided self-identification data. Table 1 provides the screen-eligible population, unique participants, and FIT participation over the 10-year study period all characterized by race/ethnicity. Over 10 years, 59% of the eligible population participated in CRC screening by returning at least one FIT.

Conclusions

CRC screening participation by race/ethnicity in Canada is unknown. This analysis of the NSCCPP suggests that participation by racialized individuals including Black/African Canadian, Asian, and Indigenous, are lower relative to White individuals. Further analyses will explore race/ethnicity and gender in terms of temporal and geographic trends.

Table 1.

Funding Agencies

None

A77 IMPLEMENTATION OF GUT LINK-IBS; RESULTS OF A SEMI-STRUCTURED INTERVIEW OF PRIMARY CARE PROVIDERS

Background

The Division of Digestive Care and Endoscopy in Halifax, Nova Scotia has had longstanding challenges with GI referral volume outstripping divisional capacity resulting in limited access to specialist care. Many referrals for functional bowel disorders (FBD) are returned to referring providers. Although this helps rationalize limited system resources, it often impairs access to appropriate and necessary GI care. The co-development and implementation of clinical care pathways across gastroenterology and primary care may help to improve access to high-quality GI care.

Aims

The project aimed to engage primary healthcare providers (PHCPs) to identify environmental and behavioral barriers and facilitators for managing undifferentiated lower GI disorders in primary care. Data generated from stakeholder engagement will be used to develop, implement, and evaluate strategies for referral and management of FBD. A real-world, functional clinical care pathway that supports the implementation of evidence-based practices in the diagnosis and management of functional GI conditions within primary care will enhance care and timely access to specialist.

Methods

This is a qualitative study using semi-structured interviews of PHCPs working in Nova Scotia. Interview questions were developed and guided by the evidence-based implementation science frameworks. Physicians were recruited through existing primary care networks. Participants were offered a Zoom™virtual semi-structured interview. A brief intake questionnaire was administered to collect baseline demographics. Interviews were recorded and transcribed for data analysis. Data were categorized into coding schemes and themes were created using an inductive coding approach.

Results

As of October 2021, 9 interviews have been conducted. Average participant age was 44 years, with the majority identifying practice in a group or collaborative care setting (n=7, 78%). Five worked in urban practice settings and the remainder in rural areas. Preliminary major themes included:

1. A lack of satisfaction with access to gastrointestinal care, with most physicians noting it to be worse than access to other specialist services.

2. Management of FBDs were felt to be within the scope of primary care practice

3. Access to diagnostic tests like fecal calprotectin with appropriate education on its use as a diagnostic tool would be useful.

4. PHCP’s suggested care pathways be easy to use, require minimal time, and ideally be implemented within their pre-existing EMR or in paper form.

Conclusions

PHCPs acknowledge a significant burden of undifferentiated lower GI complaints in their practice and poor access to gastroenterology services. All participants were open to helping develop and use a clinical care pathway for the investigation and management of undifferentiated lower GI symptoms. Data collection and analysis are ongoing.

Funding Agencies

None

Residual Antimicrobial Coating Efficacy Against SARS-CoV-2

AIMS

This study evaluated the residual efficacy of commercially available antimicrobial coatings or films against SARS-CoV-2 on nonporous surfaces.

METHOD AND RESULTS

Products were applied to stainless steel or ABS plastic coupons and dried overnight. Coupons were inoculated with SARS-CoV-2 in the presence of 5% soil load. Recovered infectious SARS-CoV-2 was quantified by TCID50 assay. Tested product efficacies ranged from <1.0 to >3.0 log₁₀ reduction at a 2-hour contact time. The log₁₀ reduction in recovered infectious SARS-CoV-2 ranged from 0.44 to 3 log₁₀ reduction on stainless steel and 0.25 to >1.67 log₁₀ on ABS plastic. The most effective products tested contained varying concentrations (0.5 to 1.3%) of the same active ingredient: 3- (trihydroxysilyl) propyldimethyloctadecyl ammonium chloride. Products formulated with other quaternary ammonium compounds were less effective against SARS-CoV-2 in this test.

CONCLUSIONS

The residual antimicrobial products tested showed varied effectiveness against SARS-CoV-2 as a function of product tested. Several products were identified as efficacious against SARS-CoV-2 on both stainless steel and ABS plastic surfaces under the conditions evaluated. Differences in observed efficacy may be due to variation in active ingredient formulation; efficacy is, therefore, difficult to predict based upon listed active ingredient and its concentration.

SIGNIFICANCE AND IMPACT

This study highlights formulation-specific efficacy of several products against SARS-CoV-2 and may inform future development of residual antiviral products for use on nonporous surfaces. The identification of antimicrobial coatings or films showing promise to inactivate SARS-CoV-2 suggests that these products may be worth future testing and consideration.

A109 LINKING PRIMARY AND SPECIALTY CARE FOR THE MANAGEMENT OF DIGESTIVE HEALTH CONDITIONS: AN EVALUATION OF GUT LINK IMPLEMENTATION

Background

Severe restrictions on in-person encounters and endoscopic procedures for digestive care have occurred as a result of the COVID-19 pandemic. This has exacerbated pre-existing barriers in access to gastroenterology (GI) care across Nova Scotia (NS) for patients and primary healthcare providers (PHCPs). In response, a provincial PHCP-GI consultative service (GUT LINK) was implemented at a single tertiary care center with the goal of supporting PHCPs in the management of non-urgent GI referral conditions.

Aims

To implement and evaluate the acceptability, feasibility, appropriateness, and early effectiveness of the GUT LINK PHCP-GI consultation service.

Methods

This is an ongoing prospective observational cohort study. All referrals received through the EMR-based referral and triage management system between May and November 2020 that were deemed to be amenable to management within primary care with specialist support were returned to the PHCP with the suggestion to arrange a GUT LINK telephone consultation. GUT LINK appointments were scheduled through an administrative support telephone line with the PHCP and a GI specialist. A post-consultation e-questionnaire was distributed to PHCPs who consented to participate. Feasibility (number of and indication for referrals, PHCP participation rates), acceptability and appropriateness (satisfaction, future use, likelihood to recommend) metrics and outcomes (case resolution, re-referrals, proportion requiring endoscopic investigations) were recorded. Patient charts were reviewed to determine whether the patient ultimately required GI speciality care. Analyses were descriptive and expressed as frequencies, means (+/-SD), medians (+/-SE), and proportions (%).

Results

A total of 45 GUT LINK consultations were completed between May and November 2020. Of these, 20% required GI specialist care and 80% have remained within primary care, with a median follow-up of 101 (+/-9.1) days. The indications for GUT LINK consultation included lower GI symptoms (64%), abnormal imaging or investigations (17%), and upper GI symptoms (19%).

To date, 21 PHCP agreed to be contacted for the post-consultation survey and 10 have been completed. All PHCPs reported that GUT LINK consultation was easy to access, while 90% found the advice helpful and 80% reported that that it resolved the issue. Following the GUT LINK appointment, 80% felt they would not need to refer their patient to GI.

Conclusions

The implementation of GUT LINK was acceptable, feasible, and improved access to specialist support for management of undifferentiated GI symptoms. Future research will focus on comprehensive stakeholder engagement in order to design, implement, and evaluate GUT LINK PHCP care pathways.

Funding Agencies

CAG

A112 THE IMPACT OF CENTRAL COORDINATION ON ENDOSCOPY EFFICIENCY

Background

The impacts of the COVID-19 pandemic have been far reaching and have necessitated many changes to healthcare delivery. At the QEII Health Sciences Center physical space limitations for patient check-in and recovery have restricted outpatient endoscopy to 3 of 4 available endoscopy suites. On June 1, 2020 a new system of central endoscopy triage and coordination for the Division of Digestive Care and Endoscopy (DC&E) was implemented in an effort to increase efficiency and maintain patient access to endoscopy. The components of the RESET (Re-introduce Endoscopy Safely and EfficienTly) Plan included a) a new endoscopy coordinator role to manage a common endoscopy waitlist, endoscopist schedules, and booking clerks, b) a modified triage system to improve waitlist consistency, c) a common endoscopy waitlist with patients booked in the next available appointment regardless of endoscopist, d) discontinuation of fixed endoscopy slots for endoscopists, and e) appointment scheduling no sooner than 4-weeks in advance to minimize no-shows and last-minute cancellations.

Aims

The aim of this study is to evaluate the impact of the RESET Plan on the efficiency of DC&E endoscopy.

Methods

A retrospective pre- and post-implementation study evaluating the volume and efficiency of outpatient endoscopy before and after implementation of the RESET Plan. The Pre-RESET period included all procedures performed from June 1, 2019 to October 31, 2019. The Post-RESET period included all procedures performed from June 1, 2020 to October 31, 2020. A separate endoscopy suite and triage system is used for endoscopic retrograde cholangiopancreatography (ERCP) and these cases were excluded. Early effectiveness outcomes were reported including a comparison of the number of endoscopic procedures per week and per list, pre- and post- implementation. Data analysis was primarily descriptive with data expressed as frequencies, means (SD), and proportions (%). Exploratory group comparisons were performed using independent-samples T-Test.

Results

During the 5-month Pre-RESET period, 2203 endoscopic procedures were performed. During the Post-RESET period a total of 1920 procedures were performed. Due to pandemic restrictions, there was a 29% decrease in available endoscopy lists from 2019 to 2020. There was a 24% increase in the number procedures performed per endoscopy list, from 6.4 to 8.0 (p=0.004, 95% CI 0.52–2.53), pre- and post-RESET.

Conclusions

While the COVID-19 pandemic has disrupted healthcare delivery, it has also provided an opportunity to implement health system structure and process changes. The RESET Plan resulted in significant gains in efficiency which largely offset losses in endoscopy throughput imposed by COVID-19 pandemic restrictions. Future research will determine what patient and health system factors most significantly impact system efficiency as well as the cost-effectiveness of the RESET Plan.

Funding Agencies

CAG

A175 BEHAVIORAL INTERVENTIONS TO ADDRESS INFLAMMATORY BOWEL DISEASE-RELATED DISTRESS AND QUALITY OF LIFE: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Inflammatory bowel disease-associated psychological distress (IBD-PD) (inclusive of anxiety, depression, and high levels of stress) is prevalent amongst persons living with IBD. IBD-PD impairs quality of life (QoL) and worsens disease outcomes. Research relating to the efficacy of behavioral interventions for IBD-PD has been limited.

Aims

This systematic review and meta-analysis was conducted to evaluate the efficacy of cognitive behavioral therapy (CBT)-based interventions for the management of IBD-PD and QoL in persons living with IBD.

Methods

Pre-defined criteria were used to identify randomized controlled studies reporting on the efficacy of CBT-based interventions for IBD-PD and QoL in adults living with IBD. Electronic databases including CINAHL, Cochrane Library, Embase, MEDLINE, PsycArticles, PsycInfo, Pubmed, and Web of Science were searched from inception to May 30, 2020. Studies published in English or French were included. Risk of bias was assessed using the Cochrane risk-of-bias tool by two independent reviewers (CH and MRF). Data was extracted and summarized qualitatively. A random-effects model was used to generate pooled estimates.

Results

Eight studies (922 participants) met criteria for inclusion in this review. The studies evaluated outcomes of quality of life and IBD-PD using the IBD Questionnaire (IBDQ), United Kingdom IBDQ, Short IBSQ, 36-Item Short Form Survey (SF-36), Short Health Scale, Perceived Stress Questionnaire (PSQ), Perceived Stress Scale (PSS-10), Hospital anxiety depression scale (HADS) and the Depression, Anxiety and Stress Scale-21 Items (DASS-21). Of the 8 studies, 2 were low, 2 high, and 4 at intermediate risk of bias. Interventions, duration, and outcome assessments differed across studies and observed attrition rates were high. The pooled odds ratio for the short-term impact of CBT on IBDQ (n=3) was 0.30 (95% CI 0.17- 0.44) favoring CBT. Perceived stress (PSQ and PSS-10) were only reported in 3 studies as secondary outcomes. Overall, CBT had no observed benefit for perceived stress. Measurement of anxiety and depression was inconsistent across studies. The impact of CBT on anxiety and depression varied with studies revealing both neutral and positive results.

Conclusions

In patients IBD-PD, CBT-based interventions were observed to lead to short-term improvements in disease-related QoL. The impact of CBT on IBD-PD remains unclear due to limitations in study quality and heterogeneity in study design. Further studies are needed to evaluate the efficacy of CBT-based interventions for IBD-PD and to define the role of behavioral interventions delivered within the context of collaborative, biopsychosocial models of care. Expert consensus on best practice for CBT-based interventions and IBD-PD evaluation are needed.

Funding Agencies

None

A107 IMPROVING ACCESS TO URGENT GASTROENTEROLOGICAL CONSULTATION: A POSITIVE PANDEMIC IMPACT

Background

The global COVID-19 pandemic has resulted in a dramatic re-alignment of clinical service delivery. In mid-March 2020 the Division of Digestive Care and Endoscopy at Dalhousie University leveraged eHealth technology to rapidly implemented a new referral management and triage system and established a new rapid outpatient consultation service to facilitate urgent virtual and face-to-face appointments. Standardized procedures for triaging, booking, and staffing the urgent gastroenterology consultation service were implemented.

Aims

The aim of this study was to evaluate the impact of the implementation of a standardized triage and consultation process on access to urgent gastroenterology consultative services at a single tertiary care center during the COVID-19 pandemic.

Methods

We performed a pre- and post-implementation study comparing efficiency metrics for urgent triage and urgent consultation. The pre-implementation cohort included all patients referred and triaged to an urgent clinic appointment between April 1, 2019 to September 30, 2019. The post-implementation cohort included all patients referred and triaged to an urgent clinic appointment between April 1, 2020 to September 30, 2020.

Healthcare efficiency data was extracted through electronic record review with specific dates and times for referral receipt (a), triage completion (b), appointment wait-listing (c), and clinic appointment (d). The time to triage (TT), time to visit (TV), and total time to consult (TC) were calculated (TT = c - a; TV = d - c; TC = TT + TV) for each patient. The Mann–Whitney U test was used to compare TT, TV, CT between patient cohorts.

Results

A total of 429 patients were booked for urgent clinic consultation, 176 during the pre-implementation period and 253 in the post-implementation period. The mean TT for the pre-and post-implementation cohorts was 4.8 days and 3.3 days, respectively (U=18,149, p=0.001). Mean TV was decreased from 16.2 days for the pre-implementation cohort to 3.6 days for the post-implementation cohort (U=6095, p=0.000). The mean time from a referral being received to the patient being seen in consultation (TC) decreased by 67% from 21 days to 6.9 days, Figure 1 (U=6,419, p=0.000).

Conclusions

The COVID-19 pandemic has had a dramatic impact on healthcare delivery in Nova Scotia. One positive result is that it facilitated the motivation and alignment needed to make a large health system change that may not have otherwise been possible. This study demonstrates that a standardized pathway for urgent outpatient gastroenterology assessment improves the timeliness of care delivery.

Funding Agencies

None

The effects of pregnancy on the pharmacokinetics of infliximab and adalimumab in inflammatory bowel disease

BACKGROUND

Transplacental transfer of infliximab and adalimumab results in detectable drug levels in the cord blood and infant.

AIM

To determine if pregnancy influenced the pharmacokinetics of anti-TNF agents in women with inflammatory bowel disease.

METHODS

Twenty-five women from the University of Calgary inflammatory bowel disease(IBD) pregnancy clinic on maintenance infliximab or adalimumab were recruited prospectively with serum bio-banking performed each trimester. Infliximab trough and adalimumab steady-state levels were the outcomes of interest and were analysed using the ANSER infliximab and adalimumab assays. Multivariate linear mixed-effects models were constructed to assess infliximab and adalimumab drug levels during pregnancy adjusting for the clinical covariates of albumin, BMI and CRP.

RESULTS

Fifteen women (eight Crohn's disease, seven ulcerative colitis) received infliximab and 10 women with 11 pregnancies were treated with adalimumab. Median age was 29.6 years (IQR: 27.6-31.2 years). Median disease duration was 9.2 years (IQR: 3.16-15.0 years). Median trough infliximab concentrations were 8.50 μg/mL (IQR: 7.23-10.07 μg/mL), 10.31 μg/mL (IQR: 7.66-15.63 μg/mL) and 21.02 μg/mL (IQR: 16.01-26.70 μg/mL) at trimesters 1, 2 and 3 respectively. Significant changes in albumin and BMI (P < 0.05) but not CRP (P > 0.05) were documented throughout pregnancy. After adjusting for albumin, BMI and CRP, infliximab trough levels increased during pregnancy, by 4.2 μg/mL per trimester (P = 0.02), while adalimumab drug levels remained stable (P > 0.05).

CONCLUSIONS

Infliximab levels rise during pregnancy, whereas adalimumab levels remain stable after accounting for changes in albumin, BMI and CRP. Therapeutic drug monitoring in the second trimester may be useful in guiding dosing in the third trimester.

Global longitudinal strain: a useful everyday measurement?

Herceptin (Trastuzumab) is a widely used and effective drug for the treatment of Her2+ breast cancer but its cardiotoxic side effects require regular monitoring by echocardiography. A 10% reduction in left ventricular ejection fraction can lead to suspension of treatment and therefore has significant implications for patient prognosis in terms of cardiac and cancer outcomes. Assessment of LV function by conventional 2D biplane method of discs (2DEF) has limitations in accuracy and reproducibility. Global longitudinal strain (GLS) is becoming more widely available and user friendly. It has been shown to demonstrate myocardial damage earlier in treatment than 2DEF, allowing the option of pharmacological intervention at a pre-clinical stage and preventing the interruption of Herceptin. This study compares the reproducibility of GLS with that of 2DEF in a routine clinical environment. Fifty echocardiograms performed on female patients undergoing Herceptin treatment were used to measure both 2DEF and GLS within the recommended standard appointment time of 40 min. The data were re-measured (blind) by the same operator a minimum of 14 days later to determine intra-operator variation. These data were also measured by a second operator (blind), to assess inter-operator variation. Analysis by direct comparison, intra-class correlation (ICC), coefficient of variation (CV) and Bland–Altman plots demonstrated that GLS is a more reproducible measurement than 2DEF. This is important to prevent clinical decisions being erroneously based on variation in operator measurement. The investigation also shows that with advances in machine software this is a practical addition to routine assessment rather than merely a research tool.

Prognosis in Paracetamol Self-Poisoning: The Use of Plasma Paracetamol Concentration in a Region without a Poisoning Treatment Centre

Published criteria for prognosis following self-poisoning with paracetamol have been applied to 30 cases in a region without centralised facilities for investigation of the poisoned patient. The results show that, despite difficulties in collection and transport of specimens, useful prognostic indices can be provided by a central laboratory. The biochemical assessment of liver damage is discussed and one of two fatal cases is presented in detail.

Simplified Gas Chromatographic Assay for Paracetamol

A rapid gas liquid chromatography method has been developed which is suitable for emergency estimations of paracetamol in overdose. The method is compared with a standard ultraviolet method.

Characterisation of two conopressin precursor isoforms in the land snail, Theba pisana

Increased understanding of the molecular components involved in mollusc reproduction may assist in understanding the evolutionary adaptations used by animals, including hermaphrodites, to produce offspring. The neuropeptide conopressin, a member of the vasopressin/oxytocin-like peptide family, can modulate various reproductive activities in invertebrates. In this study, we used the hermaphroditic land snail, Theba pisana, to investigate the presence and tissue-specific distribution of a conopressin gene. Our transcriptomic analysis of T. pisana CNS sheath tissue has revealed two conopressin gene transcripts (Tpi-conopressin-1 and Tpi-conopressin-2), each encoding for precursors containing an identical conopressin nonapeptide and a variable neurophysin. T. pisana conopressins share high identity with other land snails and slugs, as well as other mollusc and vertebrate vasopressin/oxytocin, supported by phylogenetic analysis. Conserved residues in the T. pisana neurophysin are important for peptide binding, and we present molecular dynamic models demonstrating the most likely stable structure of the Tpi-conopressin-1 peptide when associated with neurophysin. RT-PCR shows that Tpi-conopressin-1 is additionally expressed in reproductive tissues, including the dart sac, where abundant spatial expression throughout the sac region is found; this implies a role in 'love' dart synthesis or dart injection during mating. The presence of a conopressin receptor in the CNS sheath indicates CNS neural excitation. In summary, this study represents a detailed molecular analysis of conopressin in a land snail.

Strain rate imaging pre- and post-percutaneous coronary intervention: a potential role in the objective detection of ischaemia in exercise stress echocardiography

AIMS

To determine the feasibility of strain rate imaging (SRI) in the objective detection of exercise-induced ischaemia.

METHODS AND RESULTS

Sixteen patients undergoing elective percutaneous coronary intervention (PCI) underwent treadmill exercise stress echocardiography (ESE) pre- and post-PCI. Measurement of systolic SRI parameters was attempted in all myocardial segments at baseline, peak stress, and in recovery. Segments were divided into those supplied by target (Group 1) and non-target vessels (Group 2). Percutaneous coronary intervention was successful in all patients. In Group 1, there was no significant difference in post-systolic strain rate (SRps) at baseline or at peak stress but there was significantly greater SRps pre-PCI compared with post-PCI at 30 min into recovery (-0.37 +/- 0.53 vs. -0.07 +/- 0.44 s(-1), P = 0.004). There were similar findings with the SRps index [ratio of SRps:peak systolic strain rate (SRsys)]. Group 2 segments did not demonstrate any significant differences in SRI parameters pre- and post-PCI. At peak exercise pre-PCI, Group 1 segments had significantly delayed time to SRsys compared with Group 2 (0.12 +/- 0.05 vs. 0.09 +/- 0.05 s, P = 0.013), a difference that was abolished post-PCI.

CONCLUSION

This suggests a potential role for SRI in the objective detection of exercise-induced ischaemia by echocardiography at peak stress and during recovery at the time of improved image quality.

NT-proBNP and the diagnosis of left ventricular systolic dysfunction within two acute NHS trust catchment areas: the initial Teesside experience

PURPOSE

To evaluate the predictive value of N-terminal pro B-type natiuretic peptide (NT-proBNP) reference cut-off values as diagnostic markers for left ventricular systolic dysfunction (LVSD).

STUDY DESIGN

A retrospective study assessing the use of NT-proBNP in the diagnostic algorithm for the investigation of patients with suspected signs and symptoms of LVSD presenting to primary care.

RESULTS

A generic NT-proBNP cut-off (150 ng/l) value has similar negative and positive predictive valves, specificity and sensitivity compared to age and sex specific cut-off values.

CONCLUSION

When using NT-proBNP as a triage tool for screening patients with signs and symptoms suggestive of LVSD, a simple generic cut-off level is as effective as more complex age sex specific cut-off values.

Stentless vs. stented aortic valve bioprostheses: a prospective randomized controlled trial

AIMS

We sought to assess the haemodynamic profile of the Freedom stentless aortic valve compared with a stented bioprosthesis in a randomized controlled trial using echocardiography.

METHODS AND RESULTS

Sixty patients (mean age 73 years) undergoing bioprosthetic aortic valve replacement (AVR) were randomized to either Sorin Freedom stentless (n=31) or Sorin More stented (n=29) valves. The primary endpoints were left ventricular mass index (LVMI) reduction at 6 and 12-months. We also assessed post-operative effective orifice area index (EOAI), aortic gradient and operative time. There were no significant differences in baseline characteristics. The stentless valve was associated with a lower post-operative gradient [PG 17 (12) vs. 31 (13) mmHg, P<0.0001] and greater EOAI [1.1 (0.3) vs. 0.8 (0.2) cm2/m2, P<0.0001]. A highly significant reduction in LVMI occurred by 6 months in both groups, but LVMI was significantly lower in the stentless group [LVMI 119 (39) vs. 135 (30) g/m2, P=0.05]. However, there was continued regression of left ventricular hypertrophy (LVH) in the stented but not in the stentless group, resulting in no significant difference in LVMI at 12 months [119 (36) vs. 126 (31) g/m2, P=0.42].

CONCLUSION

The use of the Sorin Freedom stentless bioprosthesis for AVR results in lower PG and greater EOA when compared with a Sorin More stented valve. This is associated with earlier regression of LVH.

Immigrant women family caregivers in Canada: implications for policies and programmes in health and social sectors

Migration has become a profound global phenomenon in this century. In Canada, uncoordinated policies, including those related to immigration, resettlement, employment, and government funding for health and social services, present barriers to immigrant women caregivers. The purpose of this paper is to share relevant insights from individual and group interviews with immigrant women family caregivers, service providers and policy influencers, and discuss these in relation to immigration, health and social policy, and programme trends in Canada. The present authors conducted individual interviews with immigrant women family caregivers (n = 29) in phase 1, followed by two group interviews with women family caregivers (n = 7), and two group interviews with service providers and policy-makers (n = 15) in phase 2. Using an inductive approach, the authors employed thematic content data analysis. Immigrant women experienced barriers to health and social services similar to Canadian-born family caregivers, particularly those who have low incomes, jobs with limited flexibility and heavy caregiving demands. These immigrant women family caregivers avoided certain formal services for a variety of reasons, including lack of cultural sensitivity. However, their challenges were compounded by language, immigration and separation from family in the home country. The identified barriers to support reinforce the importance of modifying and expanding policies and programmes affecting immigrant women's ability to care for family members with illnesses or disabilities within the context of Canadian society. Participants recommended changes to policies and programmes to deal with information, transportation, language, attitudinal and network barriers. The various barriers to services and programmes which were experienced by immigrant women caregivers underscore the importance of reviewing policies affecting immigration, caregiving, and access to health and social services. Intersectoral collaboration among agencies is essential to reduce the barriers identified in the present study, and to establish services which are linguistically and culturally appropriate.

Monitoring of end tidal carbon dioxide and transcutaneous carbon dioxide during neonatal transport

OBJECTIVE

To assess the accuracy of measurements of end tidal carbon dioxide (CO2) during neonatal transport compared with arterial and transcutaneous measurements.

DESIGN

Paired end tidal and transcutaneous CO2 recordings were taken frequently during road transport of 21 ventilated neonates. The first paired CO2 values were compared with an arterial blood gas. The differences between arterial CO2 (Paco2), transcutaneous CO2 (TcPco2), and end tidal CO2 (Petco2) were analysed. The Bland-Altman method was used to assess bias and repeatability.

RESULTS

Petco2 correlated strongly with Paco2 and TcPco2. However, Petco2 underestimated Paco2 at a clinically unacceptable level (mean (SD) 1.1 (0.70) kPa) and did not trend reliably over time within individual subjects. The Petco2 bias was independent of Paco2 and severity of lung disease.

CONCLUSIONS

Petco2 had an unacceptable under-recording bias. TcPco2 should currently be considered the preferred method of non-invasive CO2 monitoring for neonatal transport.

One year results of the Middlesbrough early revascularisation to limit infarction (MERLIN) trial

OBJECTIVE

To report one year results of the MERLIN (Middlesbrough early revascularisation to limit infarction) trial, a prospective randomised trial comparing the strategy of coronary angiography and urgent revascularisation with conservative treatment in patients with failed fibrinolysis complicating ST segment elevation myocardial infarction (STEMI). The 30 day results have recently been published. At the planning stage of the trial, it was determined that follow up of trial patients would continue annually to three years to determine whether late benefit occurred.

SUBJECTS

307 patients who received a fibrinolytic for STEMI but failed to reperfuse early according to previously described ECG criteria and did not develop cardiogenic shock.

METHODS

Patients were randomly assigned to receive either emergency coronary angiography with a view to proceeding to urgent revascularisation (rescue percutaneous coronary intervention (rPCI) arm) or continued medical treatment (conservative arm). The primary end point was all cause mortality at 30 days. The secondary end points included the composite end point of death, reinfarction, stroke, unplanned revascularisation, or heart failure at 30 days. The same end points were evaluated at one year and these results are presented.

RESULTS

All cause mortality at one year was similar in the conservative arm and the rPCI arm (13.0% v 14.4%, p = 0.7, risk difference (RD) -1.4%, 95% confidence interval (CI) -9.3 to 6.4). The incidence of the composite secondary end point of death, reinfarction, stroke, unplanned revascularisation, or heart failure was significantly higher in the conservative arm (57.8% v 43.1%, p = 0.01, RD 14.7%, 95% CI 3.5% to 25.5%). This was driven almost exclusively by a significantly higher incidence of subsequent unplanned revascularisation in the conservative arm (29.9% v 12.4%, p < 0.001, RD 17.5%, 95% CI 8.5% to 26.4%). Reinfarction and clinical heart failure were numerically, but not statistically, more common in the conservative arm (14.3% v 10.5%, p = 0.3, RD 3.8%, 95% CI -3.7 to 11.4, and 31.2% v 26.1%, p = 0.3, RD 5.0%, 95% CI -5.1 to 15.1). There was a strong trend towards fewer strokes in the conservative arm (1.3% v 5.2%, p = 0.06, RD -3.9%, 95% CI -8.9 to 0.06).

CONCLUSION

At one year of follow up, there was no survival advantage in the rPCI arm compared with the conservative arm. The incidence of the composite secondary end point was significantly lower in the rPCI arm, but this was driven almost entirely by a highly significant reduction in the incidence of further revascularisation.

Adverse effects associated with the use of South African traditional folk remedies

Although the toxicity of traditional folk remedies is well known in Africa, it is a subject which is surrounded by secrecy and has not been comprehensively studied.

OBJECTIVES

The aims of this study are to describe the clinical features of patients admitted to hospital with a confirmed history of using folk remedies, and to gather data on their toxicity in a systematic fashion.

DESIGN

Prospective case series.

SETTING

Paediatric and adult wards of academic hospitals in Johannesburg, South Africa.

SUBJECTS

The study population included 103 patients ranging from one day to 75 years of age, all of whom had recent folk remedy use.

MAIN OUTCOME MEASURES

All available clinical data were analysed. Primary outcomes were the presence of renal and liver dysfunction, death or discharge from hospital.

RESULTS

The most common clinical features on presentation were dehydration (51%), vomiting (46%), jaundice (40%), diarrhoea (39%), altered mental status (37%) and oligoanuria (30%). Renal dysfunction was present in 76% of patients and liver dysfunction in 48%. The overall mortality was 34%. The odds ratio of death was 5.1 (95% CI 1.41 to 18.5) in patients with renal dysfunction (p = 0.0077) and 5.35 (95% CI 1.99 to 14.4) in patients with liver dysfunction (p = 0.0006).

CONCLUSION

Renal and liver dysfunction are frequently associated with use of folk remedies, and mortality in these patients is high. In view of the large numbers of African individuals living in the United States and Europe, it is important for physicians elsewhere to be aware of the potential toxicity of African folk remedies, and to inquire about their use.

Early and late reactions following the use of iopamidol 340, iomeprol 350 and iodixanol 320 in cardiac catheterization

GOAL

To investigate the incidence of early (< 24 hours) and late (> 24 hours to 7 days) reactions to 3 contrast agents commonly used in cardiac catheterization.

METHODS AND RESULTS

A total of 2,108 patients undergoing cardiac catheterization in a Regional Cardiothoracic Unit were randomly assigned to receive 1 of 3 commonly used contrast agents in a prospective, double-blind study. The contrast agents were iopamidol 340 (Niopam ), a nonionic monomer; iomeprol 350 (Iomeron ), a nonionic dimer; and iodixanol 320 (Visipaque ), a nonionic dimer. The main outcome measures were the incidence of early (< 24 hours) reactions following catheterization and the incidence of late (24 hours to 7 days) reactions. Early reactions, excluding patients with heat on left ventriculography as the sole symptom, were relatively common (7.4%), but there was no significant difference between the 3 agents (p = 0.35). Late skin reactions, excluding reactions solely at the site of the arterial puncture and continuations of early urticarial reactions, were also relatively common (5.4%), but the incidence differed between the 3 agents. Such reactions occurred in 2.7% of those receiving iopamidol 340 (Niopam ), 3.5% of those receiving iomeprol 350 (Iomeron ) and 10.4% of those receiving iodixanol 320 (Visipaque ) (p < 0.01).

CONCLUSION

The incidence of early adverse reactions is similar with these 3 contrast agents. However, late skin reactions are significantly more common with iodixanol 320 (Visipaque ) than with the other 2 agents. Although such reactions were rarely troublesome, patients should be advised accordingly.

The cytotoxic effects of a traditional Zulu remedy, impila (Callilepis laureola)

The traditional Zulu remedy impila (Callilepis laureola) can cause acute fatal hepatocellular necrosis, especially in children. We investigated the mechanism(s) of toxicity using HuH-7 hepatocytes. Impila tubers were extracted with boiling water and the aqueous extract was used at different concentrations to study the effects on the morphology of the cells. Flow cytometry and labelling with fluorescent antibodies to tubulin were also used. At high concentrations, necrosis occurred; however, at lower concentrations, the extracts gave rise to a variety of changes including hypercondensation of chromatin, multinucleate cells, nuclear fragmentation and apoptosis. In addition, we observed destruction of cytoplasmic tubulin. These findings give further insight into the mechanism of toxicity of herbal remedies containing atractyloside.

Partial liquid ventilation and nitric oxide in experimental acute lung injury

OBJECTIVE

To investigate the effects of inhaled nitric oxide (iNO) and partial liquid ventilation (PLV) on oxygenation and pulmonary haemodynamics in acute lung injury (ALI), and to assess their effects on lung function, systemic haemodynamics and lung injury.

METHODS

Using saline lung lavage, ALI was induced in 18 piglets. A control group was ventilated with conventional mechanical ventilation (CMV) for 2 h. An iNO-first group received iNO for the first hour and then iNO with PLV. A PLV-first group received PLV for the first hour and then PLV with iNO. Variables were measured at baseline, 5 min postlavage, and at 1 h and 2 h postlavage.

RESULTS

During the first hour, both treatment groups showed improvement in oxygenation index (OI). At 2 h, the dif-ferences in OI were statistically significant (P = 0.037), with a mean +/- SD of 23.8 +/- 20.7 in the control group, 4.4 +/- 0.9 in the PLV-first group and 6.5 +/- 3.1 in the iNO-first group. The OI was similar in both treatment groups (P = 0.178). At 2 h, the pulmonary artery pressure (PAP) was significantly different (P = 0.04) between groups, with a mean +/- SD PAP of 36.3 +/- 7.2 mmHg in the control group, 27.4 +/- 4.0 mmHg in the PLV-first group and 30.0 +/- 4.1 mmHg in the iNO-first group. The PAP was similar in both treatment groups (P = 0.319).

CONCLUSION

In ALI, oxygenation and pulmonary hypertension are improved with PLV and iNO given together, regardless of the order in which they are commenced.

Hepatic veno-occlusive disease as a result of a traditional remedy: confirmation of toxic pyrrolizidine alkaloids as the cause, using an in vitro technique

BACKGROUND/AIMS

A child presented with hepatic veno-occlusive disease after having been administered a short course of treatment with a traditional herbal remedy. The child subsequently died. Postmortem liver histology confirmed the diagnosis. This study aimed to investigate the hypothesis that the herbal remedy was the cause of veno-occlusive disease.

METHODS

Extracts of the traditional remedy were analysed by colorimetry and gas chromatography/mass spectrometry. Cultured hepatocytes were treated with an extract of the plant material and examined for morphological changes.

RESULTS

The screening analyses indicated the presence of toxic pyrrolizidine alkaloids, which were later confirmed by gas chromatography/mass spectrometry. The cell studies indicated dose related toxicity, with necrosis at high concentrations and apoptosis and abnormalities of the cytoskeleton at lower concentrations.

CONCLUSIONS

The simple screening techniques used allowed rapid confirmation of the presence of toxic pyrrolizidines in the remedy. The in vitro method confirmed the toxicity of herbal extracts to hepatocytes.

Gas chromatographic-mass spectrometric confirmation of atractyloside in a patient poisoned with Callilepis laureola

The South African traditional remedy Impila (Callilepis laureola) contains the mitochondrial toxin atractyloside. The plant is sold widely and continues to lead to fatalities in patients. We describe, for the first time, a simple GC-MS procedure for the identification of atractyloside, which we have applied to the gastric washing from a poisoned patient and to extracts of Impila tuber.

A fatal case of pepper poisoning

An 8 month old infant died as the result of administration of a traditional remedy, given orally as an infusion of a red powder. The symptoms on admission were coughing with diarrhoea and vomiting. Analysis of the powder using high-performance liquid chromatography (HPLC) confirmed the suspicion of capsaicin. Pepper preparations, which are used as traditional medicines, are highly toxic and their use on infants should be discouraged.

Pyrrolizidine poisoning: a neglected area in human toxicology

Pyrrolizidine poisoning in humans is regarded by most clinical toxicologists as of little relevance. However, a number of individual case studies in the West and some severe cases of mass poisoning by contaminated grains have led to increased interest in these alkaloids. The increasing use of herbal remedies, some of which contain toxic pyrrolizidines, suggests that the incidence of pyrrolizidine poisoning is likely to increase. In this review the authors describe the chemistry and metabolism of pyrrolizidine alkaloids, the salient features of pyrrolizidine poisoning, and the methods available for detection of these compounds in human fluids.