Tenecteplase versus standard of care for minor ischaemic stroke with proven occlusion (TEMPO-2): a randomised, open label, phase 3 superiority trial

BACKGROUND

Individuals with minor ischaemic stroke and intracranial occlusion are at increased risk of poor outcomes. Intravenous thrombolysis with tenecteplase might improve outcomes in this population. We aimed to test the superiority of intravenous tenecteplase over non-thrombolytic standard of care in patients with minor ischaemic stroke and intracranial occlusion or focal perfusion abnormality.

METHODS

In this multicentre, prospective, parallel group, open label with blinded outcome assessment, randomised controlled trial, adult patients (aged ≥18 years) were included at 48 hospitals in Australia, Austria, Brazil, Canada, Finland, Ireland, New Zealand, Singapore, Spain, and the UK. Eligible patients with minor acute ischaemic stroke (National Institutes of Health Stroke Scale score 0-5) and intracranial occlusion or focal perfusion abnormality were enrolled within 12 h from stroke onset. Participants were randomly assigned (1:1), using a minimal sufficient balance algorithm to intravenous tenecteplase (0·25 mg/kg) or non-thrombolytic standard of care (control). Primary outcome was a return to baseline functioning on pre-morbid modified Rankin Scale score in the intention-to-treat (ITT) population (all patients randomly assigned to a treatment group and who did not withdraw consent to participate) assessed at 90 days. Safety outcomes were reported in the ITT population and included symptomatic intracranial haemorrhage and death. This trial is registered with ClinicalTrials.gov, NCT02398656, and is closed to accrual.

FINDINGS

The trial was stopped early for futility. Between April 27, 2015, and Jan 19, 2024, 886 patients were enrolled; 369 (42%) were female and 517 (58%) were male. 454 (51%) were assigned to control and 432 (49%) to intravenous tenecteplase. The primary outcome occurred in 338 (75%) of 452 patients in the control group and 309 (72%) of 432 in the tenecteplase group (risk ratio [RR] 0·96, 95% CI 0·88-1·04, p=0·29). More patients died in the tenecteplase group (20 deaths [5%]) than in the control group (five deaths [1%]; adjusted hazard ratio 3·8; 95% CI 1·4-10·2, p=0·0085). There were eight (2%) symptomatic intracranial haemorrhages in the tenecteplase group versus two (<1%) in the control group (RR 4·2; 95% CI 0·9-19·7, p=0·059).

INTERPRETATION

There was no benefit and possible harm from treatment with intravenous tenecteplase. Patients with minor stroke and intracranial occlusion should not be routinely treated with intravenous thrombolysis.

FUNDING

Heart and Stroke Foundation of Canada, Canadian Institutes of Health Research, and the British Heart Foundation.

Quality of Life After Intravenous Thrombolysis for Acute Ischemic Stroke: Results From the AcT Randomized Controlled Trial

BACKGROUND

Recent evidence from thrombolysis trials indicates the noninferiority of intravenous tenecteplase to intravenous alteplase with respect to good functional outcomes in patients with acute stroke. We examined whether the health-related quality of life (HRQOL) of patients with acute stroke differs by the type of thrombolysis treatment received. In addition, we examined the association between the modified Rankin Scale score 0 to 1 and HRQOL and patient-reported return to prebaseline stroke functioning at 90 days.

METHODS

Data were from all patients included in the AcT trial (Alteplase Compared to Tenecteplase), a pragmatic, registry-linked randomized trial comparing tenecteplase with alteplase. HRQOL at 90-day post-randomization was assessed using the 5-item EuroQOL questionnaire (EQ5D), which consists of 5 items and a visual analog scale (VAS). EQ5D index values were estimated from the EQ5D items using the time tradeoff approach based on Canadian norms. Tobit regression and quantile regression models were used to evaluate the adjusted effect of tenecteplase versus alteplase treatment on the EQ5D index values and VAS score, respectively. The association between return to prebaseline stroke functioning and the modified Rankin Scale score 0 to 1 and HRQOL was quantified using correlation coefficient (r) with 95% CI.

RESULTS

Of 1577 included in the intention-to-treat analysis patients, 1503 (95.3%) had complete data on the EQ5D. Of this, 769 (51.2%) were administered tenecteplase and 717 (47.7%) were female. The mean EQ5D VAS score and EQ5D index values were not significantly higher for those who received intravenous tenecteplase compared with those who received intravenous alteplase (P=0.10). Older age (P<0.01), more severe stroke assessed using the National Institutes of Health Stroke Scale (P<0.01), and longer stroke onset-to-needle time (P=0.004) were associated with lower EQ5D index and VAS scores. There was a strong association (r, 0.85 [95% CI, 0.81-0.89]) between patient-reported return to prebaseline functioning and modified Rankin Scale score 0 to 1 Similarly, there was a moderate association between return to prebaseline functioning and EQ5D index (r, 0.45 [95% CI, 0.40-0.49]) and EQ5D VAS scores (r, 0.42 [95% CI, 0.37-0.46]).

CONCLUSIONS

Although there is no differential effect of thrombolysis type on patient-reported global HRQOL and EQ 5D-5L index values in patients with acute stroke, sex- and age-related differences in HRQOL were noted in this study.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03889249.

Association Between Duration of Transient Neurological Events and Diffusion-Weighted Brain Lesions

Background The relationship between duration of transient neurological events and presence of diffusion-weighted lesions by symptom type is unclear. Methods and Results This was a substudy of SpecTRA (Spectrometry for Transient Ischemic Attack Rapid Assessment), a multicenter prospective cohort of patients with minor ischemic cerebrovascular events or stroke mimics at academic emergency departments in Canada. For this study we included patients with resolved symptoms and determined the presence of diffusion-weighted imaging (DWI) lesion on magnetic resonance imaging within 7 days. Using logistic regression, we evaluated the association between symptom duration and DWI lesion, assessing for interaction with symptom type (focal only versus nonfocal/mixed), and adjusting for age, sex, education, comorbidities, and systolic blood pressure. Of 658 patients included, a DWI lesion was present in 232 (35.1%). There was a significant interaction between symptom duration and symptom type. For those with focal-only symptoms, there was a continuous increase in DWI probability up to 24 hours in duration (ranging from ≈40% to 80% probability). In stratified analyses, the increase in probability of DWI lesion with increased duration of focal symptoms was seen in women but not men. For those with nonfocal or mixed symptoms, predicted probability of DWI lesion was ≈35% and was greater in men, but did not increase with longer duration. Conclusions Increased duration of neurological deficits is associated with greater probability of DWI lesion in those with focal symptoms only. For individuals with nonfocal or mixed symptoms, about one-third had DWI lesions, but the probability did not increase with duration. These results may be important to improve risk stratification of transient neurological events.

Intravenous tenecteplase compared with alteplase for acute ischaemic stroke in Canada (AcT): a pragmatic, multicentre, open-label, registry-linked, randomised, controlled, non-inferiority trial

BACKGROUND

Intravenous thrombolysis with alteplase bolus followed by infusion is a global standard of care for patients with acute ischaemic stroke. We aimed to determine whether tenecteplase given as a single bolus might increase reperfusion compared with this standard of care.

METHODS

In this multicentre, open-label, parallel-group, registry-linked, randomised, controlled trial (AcT), patients were enrolled from 22 primary and comprehensive stroke centres across Canada. Patients were eligible for inclusion if they were aged 18 years or older, with a diagnosis of ischaemic stroke causing disabling neurological deficit, presenting within 4·5 h of symptom onset, and eligible for thrombolysis per Canadian guidelines. Eligible patients were randomly assigned (1:1), using a previously validated minimal sufficient balance algorithm to balance allocation by site and a secure real-time web-based server, to either intravenous tenecteplase (0·25 mg/kg to a maximum of 25 mg) or alteplase (0·9 mg/kg to a maximum of 90mg; 0·09 mg/kg as a bolus and then a 60 min infusion of the remaining 0·81 mg/kg). The primary outcome was the proportion of patients who had a modified Rankin Scale (mRS) score of 0-1 at 90-120 days after treatment, assessed via blinded review in the intention-to-treat (ITT) population (ie, all patients randomly assigned to treatment who did not withdraw consent). Non-inferiority was met if the lower 95% CI of the difference in the proportion of patients who met the primary outcome between the tenecteplase and alteplase groups was more than -5%. Safety was assessed in all patients who received any of either thrombolytic agent and who were reported as treated. The trial is registered with ClinicalTrials.gov, NCT03889249, and is closed to accrual.

FINDINGS

Between Dec 10, 2019, and Jan 25, 2022, 1600 patients were enrolled and randomly assigned to tenecteplase (n=816) or alteplase (n=784), of whom 1577 were included in the ITT population (n=806 tenecteplase; n=771 alteplase). The median age was 74 years (IQR 63-83), 755 (47·9%) of 1577 patients were female and 822 (52·1%) were male. As of data cutoff (Jan 21, 2022), 296 (36·9%) of 802 patients in the tenecteplase group and 266 (34·8%) of 765 in the alteplase group had an mRS score of 0-1 at 90-120 days (unadjusted risk difference 2·1% [95% CI - 2·6 to 6·9], meeting the prespecified non-inferiority threshold). In safety analyses, 27 (3·4%) of 800 patients in the tenecteplase group and 24 (3·2%) of 763 in the alteplase group had 24 h symptomatic intracerebral haemorrhage and 122 (15·3%) of 796 and 117 (15·4%) of 763 died within 90 days of starting treatment INTERPRETATION: Intravenous tenecteplase (0·25 mg/kg) is a reasonable alternative to alteplase for all patients presenting with acute ischaemic stroke who meet standard criteria for thrombolysis.

FUNDING

Canadian Institutes of Health Research, Alberta Strategy for Patient Oriented Research Support Unit.

Ethical Justification for Deferral of Consent in the AcT Trial for Acute Ischemic Stroke

The AcT trial (Alteplase Compared to Tenecteplase) compares alteplase or tenecteplase for patients with acute ischemic stroke. All eligible patients are enrolled by deferral of consent. Although the use of deferral of consent in the AcT trial meets the requirements of Canadian policy, we sought to provide a more explicit and rigorous approach to the justification of deferral of consent organized around 3 questions. Ultimately, the approach we outline here could become the foundation for a general justification for deferral of consent.

Assessing the efficacy and safety of hydroxychloroquine as outpatient treatment of COVID-19: a randomized controlled trial

BACKGROUND

Identification of therapies to prevent severe COVID-19 remains a priority. We sought to determine whether hydroxychloroquine treatment for outpatients with SARS-CoV-2 infection could prevent hospitalization, mechanical ventilation or death.

METHODS

This randomized controlled trial was conducted in Alberta during the first wave of the COVID-19 pandemic without direct contact with participants. Community-dwelling individuals with confirmed SARS-CoV-2 infection (by reverse transcription polymerase chain reaction [RT-PCR] viral ribonucleic acid test) within the previous 4 days, and symptom onset within the previous 12 days, were randomly assigned to oral hydroxychloroquine or matching placebo for 5 days. Enrolment began Apr. 15, 2020. The primary outcome was the composite of hospitalization, invasive mechanical ventilation or death within 30 days. Secondary outcomes included symptom duration and disposition at 30 days. Safety outcomes, such as serious adverse events and mortality, were also ascertained. Outcomes were determined by telephone follow-up and administrative data.

RESULTS

Among 4919 individuals with a positive RT-PCR test, 148 (10.2% of a planned 1446 patients) were randomly assigned, 111 to hydroxychloroquine and 37 to placebo. Of the 148 participants, 24 (16.2%) did not start the study drug. Four participants in the hydroxychloroquine group met the primary outcome (4 hospitalizations, 0 mechanical ventilation, 4 survived to 30 days) and none in the placebo group. Hydroxychloroquine did not reduce symptom duration (hazard ratio 0.77, 95% confidence interval 0.49-1.21). Recruitment was paused on May 22, 2020, when a since-retracted publication raised concerns about the safety of hydroxychloroquine for hospitalized patients with COVID-19. Although we had not identified concerns in a safety review, enrolment was slower than expected among those eligible for the study, and cases within the community were decreasing. Recruitment goals were deemed to be unattainable and the trial was not resumed, resulting in a study underpowered to assess the effect of treatment with hydroxychloroquine and safety.

INTERPRETATION

There was no evidence that hydroxychloroquine reduced symptom duration or prevented severe outcomes among outpatients with proven COVID-19, but the early termination of our study meant that it was underpowered.

TRIAL REGISTRATION

ClinicalTrials.gov, no. NCT04329611.

Pathways for Transformation: Disaster Risk Management to Enhance Resilience to Extreme Events

Disaster risk from extreme events and development are intimately linked. Disaster risk management influences and is affected by local development strategies. Trade-offs made in policy and implementation determine winners and losers on the basis of unequal capacity, susceptibility and hazard exposure. Transformation has been introduced as a concept opening new policy space for fundamental shifts in development trajectories. Though policy neutral, when combined with normative frameworks such as the Sustainable development goals it can open up leverage points for determining development trajectories. There is limited empirical evidence on which to base understanding of transformative disaster risk management policy though some work has been done in sister domains such as climate change mitigation and adaptation. This study asks whether transformation pathways for disaster risk management can be observed, offering an initial qualitative analysis to inform policy development. It is based on five case studies drawn from diverse locations exposed to a range of extreme events, examined through a conceptual framework offering five indicators of transformation to aid analysis: intense interaction between actors; the intervention of external actors; system level change extending beyond efficiency to governance and goals; behavior beyond established coping strategies; and behavior extending beyond established institutions. Core characteristics of transformative pathways for disaster risk reduction are identified, including pathway competition, pathway experimentation, pathway scale effects and pathway lock-in. These characteristics are seen to determine the extent to which the disruption consequent on extreme events leads to either transformatory change or relative stasis. The study concludes that transformative disaster risk management, both intentional and incidental can be observed. It is seen that transformations occur primarily at local level. Where policy level change occurs this generally played out at local level too. The particular insight of the study is to suggest that most often the burden of transformation is carried at the local level through the behavior of individuals, populations and civil society. This observation raises an important question for further work: How can the burden of undertaking transformation be shared across scales?

Tenecteplase-tissue-type plasminogen activator evaluation for minor ischemic stroke with proven occlusion

BACKGROUND AND PURPOSE

Minor stroke and transient ischemic attack with an intracranial occlusion are associated with neurological deterioration and disability. Tenecteplase (TNK-tissue-type plasminogen activator) compared with alteplase is easier to administer, has a longer half-life, higher fibrin specificity, possibly a lower rate of intracranial hemorrhage, and may be an ideal thrombolytic agent in this population.

METHODS

TNK-Tissue-Type Plasminogen Activator Evaluation for Minor Ischemic Stroke With Proven Occlusion (TEMPO-1) was a multicenter, prospective, uncontrolled, TNK-tissue-type plasminogen activator dose-escalation, safety, and feasibility trial. Patients with a National Institutes of Health Stroke Scale ≤5 within 12 hours of symptom onset, intracranial arterial occlusion on computed tomographic angiography and absence of well-evolved infarction were eligible. Fifty patients were enrolled; 25 patients at a dose of 0.1 mg/kg, and 25 patients at 0.25 mg/kg. Primary outcome was the rate of drug-related serious adverse events. Secondary outcomes included recanalization and 90-day neurological outcome (modified Rankin Scale, 0-1).

RESULTS

Median baseline National Institutes of Health Stroke Scale was 2.5 (interquartile range, 1), and median age was 71 (interquartile range, 22) years. There were no drug-related serious adverse events in tier 1. In tier 2, there was 1 symptomatic intracranial hemorrhage (4%; 95% confidence interval, 0.01-20.0). Stroke progression occurred in 6% of cases. Overall, 66% had excellent functional outcome (modified Rankin Scale, 0-1) at 90 days. Recanalization rates were high; 0.1 mg/kg (39% complete and 17% partial), 0.25 mg/kg (52% complete and 9% partial). Complete recanalization was significantly related to excellent functional outcome (modified Rankin Scale, 0-1) at 90 days (relative risk, 1.65; 95% confidence interval, 1.09-2.5; P=0.026).

CONCLUSIONS

Administration of TNK-tissue-type plasminogen activator in minor stroke with intracranial occlusion is both feasible and safe. A larger randomized controlled trial is needed to prove that this treatment is efficacious.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT01654445.

Abstract 160: Final Results of the Thrombolysis for Minor Ischemic Stroke With Proven Acute Symptomatic Occlusion Using TNK-tPA (TEMPO-1) Trial

Background: Minor stroke and TIA with an intracranial occlusion are associated with a 20-30% risk of neurological deterioration and subsequent disability. TNK-tPA compared to alteplase is easier to administer, has a longer half-life, higher fibrin specificity and possibly a lower rate of intracranial hemorrhage. Therefore, it may be an ideal thrombolytic agent for recanalization in this population.

Methods: TEMPO-1 was a multi-centre, prospective cohort, TNK-tPA dose-escalation, safety and feasibility trial. Patients with an NIHSS < 6, intracranial arterial occlusion on CTA, with no sign of well-evolved infarction who were treated within a 12h treatment window were enrolled. 50 patients were enrolled. The first 25 patients were treated at a dose of 0.1 mg/kg, and a second cohort of 25 patients treated at a dose of 0.25 mg/kg. Primary outcome was the rate of symptomatic intracranial (SICH) and extracranial hemorrhage. SICH was defined as a new ICH with ≥ 2 points worsening on the NIHSS. SITS-MOST definition of SICH was also assessed. Secondary outcomes include complete neurological (NIHSS 0-1) and functional (mRS 0-1) recovery at 90 days, recanalization at 4-8 h on CTA and minor bleeding.

Results: Median baseline NIHSS was 2 (SD 1.24) and median age was 71 years (SD 18). Site of intracranial occlusions were: MCA-M1 (13), MCA-M2 (21), MCA-M3 (8), PCA-P1 (1), PCA-P2 (1) branches, vertebral artery/PICA (3) and undetermined (3). There was one SICH seen [2% (1/50), CI95 0.5%-10.6%], which was in the 0.25mg/Kg dose tier. There were no SICH by the SITS-MOST definition. For the 0.1mg/Kg dose tier recanalization between 4-8 hours post drug was complete in 21.7%, partial in 26.1% and no recanalization was seen in 52.2%. For the 0.25mg/Kg dose tier recanalization between 4-8 hours post drug was complete in 56.6%, partial in 13% and no recanalization was seen in 30.4%. 90-day disability and neurological outcome assessment will be available at the time of the International Stroke Conference.

Conclusion: We have shown the safety and feasibility of thrombolysis with TNK-tPA in a minor stroke with intracranial occlusion population. Rates of recanalization are high in the 0.25mg/Kg tier and we have chosen this dose to proceed with a randomized controlled trial in this population.

Placebo-controlled trial of lubiprostone for constipation associated with Parkinson disease

OBJECTIVE

To evaluate the efficacy and tolerability of lubiprostone (Amitiza) for constipation in Parkinson disease (PD) in a double-blind, randomized, controlled study.

METHODS

Patients with PD and clinically meaningful constipation (constipation rating scale score > 10 [range: 0-28]) were recruited from 2 academic movement disorder centers to participate in the study. After enrollment, patients were initially followed for 2 weeks and then were randomly assigned 1:1 to lubiprostone, and the dose was titrated up to 48 μg/day. They returned 4 weeks later for a final assessment. Data included stool diaries and global impressions (co-primary endpoints), demographics, Unified Parkinson's Disease Rating Scale scores, constipation scale scores, visual analog scale (VAS) scores, a stool diary, and adverse events.

RESULTS

Fifty-four subjects (39 male, mean age 67.0 ± 10.1 years, and mean duration of PD 8.3 ± 5.4 years) were randomly assigned to lubiprostone or placebo. One patient in the drug group discontinued the study because of logistics, and one patient in the placebo group discontinued the study because of lack of efficacy. A marked or very marked clinical global improvement was reported by 16 of 25 (64.0%) subjects receiving drug vs 5 of 27 (18.5%) subjects receiving placebo (p = 0.001). The constipation rating scale (p < 0.05), VAS (p = 0.001), and stools per day in the diary (p < 0.001) all improved with drug compared with placebo. Adverse events with drug were mild, most commonly intermittent loose stools.

CONCLUSION

In this randomized controlled trial, lubiprostone seemed to be well tolerated and effective for the short-term treatment of constipation in PD.

3-Tesla versus 1.5-Tesla Magnetic Resonance Diffusion and Perfusion Imaging in Hyperacute Ischemic Stroke

BACKGROUND

Clinical 3-tesla magnetic resonance imaging systems are becoming widespread. No studies have examined differences between 1.5-tesla and 3-tesla imaging for the assessment of hyperacute ischemic stroke (<6 h from symptom onset). Our objective was to compare 1.5-tesla and 3-tesla diffusion and perfusion imaging for hyperacute stroke using optimized protocols.

METHODS

Three patients or their surrogate provided informed consent. Diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) was performed sequentially at 1.5 T and 3 T. DWI, apparent diffusion coefficient (ADC) maps and relative time-to-peak (TTP) maps were registered and assessed. DWI contrast-to-noise ratio (CNR) and ADC contrast were measured and compared. The infarct lesion volume (ILV) and thresholded ischemic volume (TIV) were estimated on the ADC and TTP maps, respectively, with the penumbral volume being defined as the difference between these volumes.

RESULTS

Qualitatively, the 3-tesla TTP images exhibited greater feature detail. Quantitatively, the DWI CNR and ILV were similar at both field strengths, the ADC contrast was greater at 3 T and the TIV and penumbral volumes were much smaller at 3 T.

CONCLUSIONS

Overall, the 3-tesla diffusion and perfusion images were at least as good and in some ways superior to the 1.5-tesla images for assessing hyperacute stroke. The TTP maps showed greater feature detail at 3 T. The ischemic and penumbra volumes were much greater at 1.5 T, indicating a potential difference in the diagnostic utility of the PWI-DWI mismatch between field strengths.

Botulinum toxin in the treatment of blepharospasm and hemifacial spasm

Blepharospasm and hemifacial spasm are the two most common craniofacial movement disorders. Blepharospasm is a syndrome characterized by excessive or continuous eye closure related to overactivity of the orbicularis oculi and adjacent muscles bilaterally. Hemifacial spasm is a peripherally-induced movement disorder typically caused by vascular compression of cranial nerve VII (CN VII) leading to involuntary unilateral contractions of muscles used in facial expression. Treatment options for both conditions include medications, botulinum toxin, and various surgical interventions. This article summarizes the existing medical literature which indicates that botulinum toxin is the treatment of choice for blepharospasm and hemifacial spasm.

Hemi-orolingual angioedema and ACE inhibition after alteplase treatment of stroke

One hundred seventy-six consecutive patients treated with IV tissue plasminogen activator (tPA) for acute ischemic stroke were examined prospectively, and orolingual angioedema was found in nine (5.1%; 95% CI 2.3 to 9.5). The reaction was typically mild, transient, and contralateral to the ischemic hemisphere. Risk of angioedema was associated with angiotensin-converting enzyme inhibitors (relative risk [RR] 13.6; 95% CI 3.0 to 62.7) and signs on initial CT of ischemia in the insular and frontal cortex (RR 9.1; 95% CI 1.4 to 30.0).

What five clinical pastoral education residents discovered from a JCAHO review

Discusses the process one pastoral care department and its five residents used to prepare for a JCAHO review and reports the experience, detailing questions asked and chaplains' responses when they sat in on twenty unit reviews.

An efficient color representation for image retrieval

A compact color descriptor and an efficient indexing method for this descriptor are presented. The target application is similarity retrieval in large image databases using color. Colors in a given region are clustered into a small number of representative colors. The feature descriptor consists of the representative colors and their percentages in the region. A similarity measure similar to the quadratic color histogram distance measure is defined for this descriptor. The representative colors can be indexed in the three-dimensional (3-D) color space thus avoiding the high-dimensional indexing problems associated with the traditional color histogram. For similarity retrieval, each representative color in the query image or region is used independently to find regions containing that color. The matches from all of the query colors are then combined to obtain the final retrievals. An efficient indexing scheme for fast retrieval is presented. Experimental results show that this compact descriptor is effective and compares favorably with the traditional color histogram in terms of overall computational complexity.

Peer group image enhancement

Peer group image processing identifies a "peer group" for each pixel and then replaces the pixel intensity with the average over the peer group. Two parameters provide direct control over which image features are selectively enhanced: area (number of pixels in the feature) and window diameter (window size needed to enclose the feature). A discussion is given of how these parameters determine which features in the image are smoothed or preserved. We show that the Fisher discriminant can be used to automatically adjust the peer group averaging (PGA) parameters at each point in the image. This local parameter selection allows smoothing over uniform regions while preserving features like corners and edges. This adaptive procedure extends to multilevel and color forms of PGA. Comparisons are made with a variety of standard filtering techniques and an analysis is given of computational complexity and convergence issues.

Study to validate the outcome goal, competencies and educational objectives for use in intensive care orientation programs

Intensive care orientation programs have become an accepted component of intensive care education. To date, however, there have been no Australian-based standards defining the appropriate level of competence to be attained upon completion of orientation. The aim of this study was to validate a set of aims, competencies and educational objectives that could form the basis of intensive care orientation and which would ensure an outcome standard of safe and effective practice. An initial document containing a statement of the desired outcome goal, six competency statements and 182 educational objectives was developed through a review of the orientation programs developed by the investigators. The Delphi technique was used to gain consensus among 13 nurses recognised for their expertise in intensive care education. The expert group rated the acceptability of each of the study items and provided suggestions for objectives to be included. An approval rating of 80 per cent was required to retain each of the study items, with the document refined through three Delphi rounds. The final document contains a validated statement of outcome goal, competencies and educational objectives for intensive care orientation programs.

Variational image segmentation using boundary functions

A general variational framework for image approximation and segmentation is introduced. By using a continuous "line-process" to represent edge boundaries, it is possible to formulate a variational theory of image segmentation and approximation in which the boundary function has a simple explicit form in terms of the approximation function. At the same time, this variational framework is general enough to include the most commonly used objective functions. Application is made to Mumford-Shah type functionals as well as those considered by Geman and others. Employing arbitrary Lp norms to measure smoothness and approximation allows the user to alternate between a least squares approach and one based on total variation, depending on the needs of a particular image. Since the optimal boundary function that minimizes the associated objective functional for a given approximation function can be found explicitly, the objective functional can be expressed in a reduced form that depends only on the approximating function. From this a partial differential equation (PDE) descent method, aimed at minimizing the objective functional, is derived. The method is fast and produces excellent results as illustrated by a number of real and synthetic image problems.

A comparison of nursing activities associated with manual and automated documentation in an Australian intensive care unit

This article describes a comparative study that examined the frequencies of nursing activities, when using a clinical information system (CIS) and a paper-based documentation system in an Australian intensive care unit. The study unit had half the beds equipped with a CIS, and the remaining beds used paper documentation. Work sampling methodology was used to observe nurses working with both systems. Though there were differences for all activities between the environments and the directions of the differences were logical, none were statistically significant using a chi-square test (P = .11-0.65), probably because of the small sample size. This study established that work sampling methodology using a random timer is a valid and relatively easy method to capture work activity in the clinical area. Although this article does not provide definitive information regarding the benefits of a CIS over manual documentation, a number of important methodological issues are discussed, including the study design, procedure, use of dedicated observers, and the distinction between basic versus fully optioned systems. Future research should evaluate the efficiency, impact on patient outcomes and nursing practice, and cost effectiveness of fully optioned systems.

Attitudes of Australian nurses toward the implementation of a clinical information system

A computerized clinical information system (CIS) used for the majority of patient charting and medical records was installed in six of 15 beds in the intensive care unit (ICU) of a large Australian hospital in November 1993. Staff acceptance was identified as integral to the success of the system. A survey was issued to all nursing staff of the ICU to identify factors that affected attitude toward computers in the critical care environment. Factors resulting in negative attitudes then could be targeted through training and support for users. The factors considered that potentially could influence attitudes were age, nursing experience, intensive care nursing experience, and education. The study showed that nursing experience had a statistically significant effect on motivation to use computers. A strong relation was evident between the concepts of beliefs, attitudes, and motivation. A less apparent association was present between knowledge and the other concepts. Orientation and in-service education programs should provide appropriate and applied information to optimize the motivation, beliefs, and computer literacy of nurses using CIS frameworks.

The development of the Australian Basic Intensive Care Knowledge Test

The Basic knowledge Assessment Tool (BKAT), a test developed in the United States, has been presented as a valid and reliable test of basic knowledge for critical care nursing. However, it was necessary to determine the BKAT's validity and reliability in the Australian intensive care (IC) context. The Delphi technique, utilising a panel of eleven experts, was used to determine the content validity of the BKAT. The Delphi process resulted in the development of a test with 105 questions. These questions consist of 49 original BKAT questions, 25 original BKAT questions slightly modified, 3 original BKAT questions with major modifications and 28 new questions. A criterion group design was used to establish the modified test's reliability and decision validity. Item analysis was undertaken using item difficulty and item discrimination indexes. The modified test was completed by 14 registered nurses with no IC experience, 18 registered nurses with intermediate IC experience and 25 registered nurses qualified as intensive care specialists. The mean score (and standard deviation) for the test for each of the respective groups was 41(9), 69(9) and 86(7). These results were significantly different (p < 0001). The reliability was established with a Cronbach Alpha coefficient of .96. The modified test is a reliable and valid measure of IC basic knowledge and can be used as a valuable adjunct in the assessment of IC orientation programs.

The effects of cage size and pair housing on exercise of beagle dogs

One of the requirements of the 1985 amendments to the Animal Welfare Act is the establishment of an exercise program for dogs. Assumptions have been made by some that larger cages or the presence of a companion animal will motivate exercise. To examine how cage size, pair housing and human contact affect exercise, a study was conducted using a computerized video-data acquisition system that measured distance traveled and time spent moving in 1 x 1 m, (single only) and 1 x 2 m (single and paired) and 1 x 1.5 m cage (paired only) cages. Male beagle dogs (n = 6) housed singly in the 1 m2 cage traveled an average of 55 m/hr spending only 8% (57 min) of the 12 h photo period in motion. When the cage size was doubled, the average distance traveled decreased to 13 m/hr and the time spent moving increased to 11% (77 min/day). When dogs were pair housed in a regulation size cage, the average distance traveled decreased to 8.6 m/hr and they spent less than 6% of the day in exercising (42 min/12 hrs). The greatest amount of exercise was seen when dogs were housed as a pair in a cage less than recommended size (an average of 109 m/hr and 8.8 min/hr). Therefore, these data indicate that larger cages or pair housing in regulation size cages have little or no effect on the activity of purpose bred male beagle dogs. There was, however, a direct correlation between activity, time and distance, and the presence of humans in the animal room.(ABSTRACT TRUNCATED AT 250 WORDS)

Collagen crosslinking and cartilage glycosaminoglycan composition in normal and scoliotic chickens

The amounts of lysine-derived crosslinks in collagens from tendon, cartilage, intervertebral disc, and bone and changes in the composition of sternal cartilage glycosaminoglycans were estimated in two lines of chickens, a control-isogenic line and a line that develops scoliosis. In the scoliotic line, scoliosis first appears at 3-4 weeks and progressively increases in severity and incidence so that 90% of the birds express the lesion by week 10. We have reported previously that cartilage, tendon, and bone collagens from scoliotic birds are more soluble than corresponding collagens from normal birds. Herein, collagen crosslinking and altered proteoglycan metabolism are examined as possible mechanisms for the differences in collagen solubility. At 1 week of age there were fewer reducible crosslinking amino acids (hydroxylysinonorleucine, dihydroxylysinonorleucine, and lysinonorleucine) in collagens from sternal cartilage and tendon in the scoliotic line than in the isogenic line. However, by week 3 and at weeks 5 or 7 values were similar in both groups. The amounts of hydroxypyridinium in vertebral bone and intervertebral disc collagen were also similar in both groups of birds. Consequently, differences in collagen crosslinking do not appear to be a persistent developmental defect underlying the expression of scoliosis in the model. However, differences were observed in cartilage proteoglycans and glycosaminoglycans from the scoliotic line that were not present in cartilage from the isogenic line. The average molecular weight of the uronide-containing glycosaminoglycans was 30% less in the scoliotic line than in the isogenic line, i.e., 12,000 compared to 18,000. The size distribution of cartilage proteoglycans from the scoliotic line also differed from that of proteoglycans from the isogenic line.(ABSTRACT TRUNCATED AT 250 WORDS)

Scoliosis in chickens. A model for the inherited form of adolescent scoliosis

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Scoliosis in chickens: responsiveness of severity and incidence to dietary copper

The severity and incidence of spinal lesions were manipulated in a line of chickens susceptible to scoliosis by varying their dietary intake of copper. A decrease in expression of the lesion was related to increased intake of copper. The change in expression, however, appeared to be related only indirectly to the defects in collagen cross-linking, maturation, and deposition known to be associated with dietary copper deficiency. Thus, a dietary constituent in the range of normal intakes may act as an environmental factor in the expression of scoliosis.

Isolation and characterization of fibronectin from bovine aqueous humor

Aqueous humor collected from freshly enucleated bovine eyes was passed over a gelatin affinity column, and bound material was eluted with 4M urea. When fractionated by sodium dodecyl sulfate electrophoresis, the eluted material co-migrated with human plasma fibronectin and protein standards of approximately 220,000 daltons. Amino acid analyses demonstrated a composition similar to that of human plasma fibronectin and fibronectin synthesized by cultured cells. The concentration of fibronectin in aqueous humor is approximately 100 times less than in human plasma.