Patient & public involvement for inherited cardiac conditions

Funding Acknowledgements

National Institute for Health Research

OnBehalf

King"s Health Partners Patient & Public Involvement for Inherited Cardiac Conditions (PPIICC) group

Background

Inherited Cardiac Conditions (ICCs) affect up to 1:200 of the population and is the leading cause of sudden death in the under 40s. Research into developing interventions to support patients as they adjust to their diagnosis and genetic carrier status is underway; an example of which is the Psychoeducational Intervention Supporting patients with an ICC (PISICC) study. To ensure the appropriateness, acceptability and applicability of the intervention, patients and the public were involved in the development of PISICC intervention.

Purpose

To ensure the relevance and improve the quality of the PISICC study, Patient & Public Involvement for Inherited Cardiac Conditions  (PPIICC) group was organised to guide the research project as this progressed through the three phases of the Medical Research Council framework for developing complex interventions.

Methods

Utilising INVOLVE guidelines, the PPIICC group was initiated by the researcher by inviting patients and families attending a local ICC clinic, members of the patient support group, Cardiomyopathy UK; and members of the existing PPI group of the local biomedical research centre. Ground rules, terms of engagement and provisions for meetings such as rooms, reimbursements for transport costs, childcare and compensation for time was established. The PPIICC group met up to three times per year within a three-year period with electronic exchanges in between. Members gave individual feedback to draft study materials and their views shaped the final versions. A modified Delphi study was used for the development of the PISICC intervention model. Figure 1 illustrates the activities undertaken by the group.

Results

The involvement of the PPIICC group throughout the development of the PISICC intervention model has contributed to the successful recruitment of 32 participants and completion of the qualitative study in Phase 1. In Phase 2 the group had a crucial role in ensuring that the education component of the PISICC intervention included  advice on medication and physical activity; and for the group component of the intervention to include a mixed age group to enable sharing of varied experiences. In planning for Phase 3, the PPIICC group helped ensure that the trial processes for the planned feasibility study were not burdensome to participants which supported its full ethical approval by the UK Health Research Authority.

Conclusions

Patients and their families played an important role in designing the PISICC study. So far, their involvement has resulted in reaching recruitment targets for Phase 1 of the study, the development of a patient-informed psychoeducational intervention model and feasibility study protocol.

The feasibility of a randomised control trial to assess physiotherapy against surgery for recurrent patellar instability

Background

Patellar instability is a relatively common condition that leads to disability and restriction of activities. People with recurrent instability may be given the option of physiotherapy or surgery though this is largely driven by clinician preference rather than by a strong evidence base. We sought to determine the feasibility of conducting a definitive trial comparing physiotherapy with surgical treatment for people with recurrent patellar instability.

Methods

This was a pragmatic, open-label, two-arm feasibility randomised control trial (RCT) with an embedded interview component recruiting across three NHS sites comparing surgical treatment to a package of best conservative care; ‘Personalised Knee Therapy’ (PKT). The primary feasibility outcome was the recruitment rate per centre (expected rate 1 to 1.5 participants recruited each month). Secondary outcomes included the rate of follow-up (over 80% expected at 12 months) and a series of participant-reported outcomes taken at 3, 6 and 12 months following randomisation, including the Norwich Patellar Instability Score (NPIS), the Kujala Patellofemoral Disorder Score (KPDS), EuroQol-5D-5L, self-reported global assessment of change, satisfaction at each time point and resources use.

Results

We recruited 19 participants. Of these, 18 participants (95%) were followed-up at 12 months and 1 (5%) withdrew. One centre recruited at just over one case per month, one centre was unable to recruit, and one centre recruited at over one case per month after a change in participant screening approach. Ten participants were allocated into the PKT arm, with nine to the surgical arm. Mean Norwich Patellar Instability Score improved from 40.6 (standard deviation 22.1) to 28.2 (SD 25.4) from baseline to 12 months.

Conclusion

This feasibility trial identified a number of challenges and required a series of changes to ensure adequate recruitment and follow-up. These changes helped achieve a sufficient recruitment and follow-up rate. The revised trial design is feasible to be conducted as a definitive trial to answer this important clinical question for people with chronic patellar instability.

Trial registration

The trial was prospectively registered on the International Standard Randomised Controlled Trial Number registry on the 22/12/2016 (reference number: ISRCTN14950321). http://www.isrctn.com/ISRCTN14950321

Genitourinary manifestations of endometriosis with emphasis on the urinary tract

Endometriosis is a common benign condition affecting women. The disease has a broad spectrum of presentations from incidental lesions in asymptomatic women to causing significant and debilitating morbidity in others. Ectopic endometrial glands are located in predictable locations throughout the pelvis, including implantation on the ovaries and in the rectouterine cul-de-sac. Less commonly, the urinary tract may be involved. As genitourinary manifestations may remain symptomatically occult or masquerade as other diagnoses, it is essential for the radiologist to be aware of the imaging features, consider this diagnosis, and potentially save the patient from delayed treatment.

Validation in Alberta of an administrative data algorithm to identify cancer recurrence

Background

Readily available population-based data about cancer recurrence would improve surveillance and research for women of reproductive age.

Methods

We randomly selected 200 women from the Alberta Cancer Registry who had received a cancer diagnosis and who ever had a pregnancy between 2003 and 2012. Administrative data were obtained and linked. Several definitions of recurrence were assessed using various minimum lengths of time between the initial diagnosis date and subsequent diagnoses or treatments, or both. Chart review was used as a "gold standard" definition of recurrence.

Results

Chart review identified recurrences in 26 women. The definition that best captured "recurrence" was 2 or more cancer diagnosis codes 10 or more months from the diagnosis date [sensitivity: 80.8%; 95% confidence interval (ci): 60.7% to 93.5%; specificity: 81.0%; 95% ci: 74.4% to 86.6%; positive predictive value: 38.9%; 95% ci: 25.9% to 53.1%; negative predictive value: 96.6%; 95% ci: 92.2% to 98.9%; kappa = 0.42; 95% ci: 0.28 to 0.57].

Conclusions

Recurrence in reproductive-aged women can be captured with moderate validity using administrative data, but should be interpreted with caution.

Empowering knowledge generation through international data network: the IMeCCHI-DATANETWORK

Introduction

The International Methodology Consortium for Coded Health Information (IMeCCHI) is a collaboration of health services researchers who promote methodological advances in coded health information. The IMeCCHI-DATANETWORK initiative focuses on developing a multi-purpose distributed data infrastructure and common data model (CDM) to enable cross-border data sharing and international comparisons.

Methods

IMeCCHI consortium partners from six different countries – Canada, Denmark, Italy, New Zealand, South Korea, and Switzerland – used a questionnaire to describe their original databases which differ in size, structure, content and coding systems. To standardize these data, they agreed on a CDM and mapped their population-based databases to meet the CDM specifications. At the end of this process, local data had a more homogenous content and structure, which made them syntactically and semantically interoperable. Data transformation was performed using a common data management software called TheMatrix.

Results

The CDM encompasses four tables of structured data (person characteristics, hospitalizations, outpatient prescription medication and death), linked at the individual level through a person identifier. It can be used to answer research questions across countries using locally converted databases, which facilitates study replication in a distributed fashion. As a proof-of-concept study, an initial research question was addressed using an agreed protocol. Local data were transformed in csv files in the CDM structure and TheMatrix was tested to transform the standardized data from each partner into local analytical datasets. This allowed results to be shared between countries, whilst maintaining local control over each region’s data.

Conclusion

The IMeCCHI-DATANETWORK, a model of a distributed data network, demonstrated that it is feasible to analyze international data using standardized analytical methods that enable independent analyses by regions, without relocating datasets thereby protecting local confidentiality obligations. The distributed data infrastructure can produce results that can be generalized to several countries, while facilitating cross-border data sharing and international comparisons.

Keywords

Common data model, international comparison, cross-border data sharing, interoperability, observational data

Cost-effectiveness of first-trimester screening with early preventative use of aspirin in women at high risk of early-onset pre-eclampsia

OBJECTIVE

Pre-eclampsia (PE) remains a leading cause of maternal and fetal morbidity and mortality. A first-trimester screening algorithm predicting the risk of early-onset PE has been developed and validated. Early prediction coupled with initiation of aspirin at 11-13 weeks in women identified as high risk is effective at reducing the prevalence of early-onset PE. The aim of this study was to evaluate the cost-effectiveness of this first-trimester screening program coupled with early use of low-dose aspirin in women at high risk of developing early-onset PE, in comparison to current practice in Canada.

METHODS

A decision analysis was performed based on a theoretical population of 387 516 live births in Canada in 1 year. The clinical and financial impact of early preventative screening using the Fetal Medicine Foundation algorithm for prediction of early-onset PE coupled with early (< 16 weeks) use of low-dose aspirin in those at high risk was simulated and compared with current practice using decision-tree analysis. The probabilities at each decision point and associated costs of utilized resources were calculated based on published literature and public databases.

RESULTS

Of the theoretical 387 516 births per year, the estimated prevalence of early PE based on first-trimester screening and aspirin use was 705 vs 1801 cases based on the current practice. This was associated with an estimated total cost of C$9.52 million with the first-trimester screening program compared with C$23.91 million with current practice for the diagnosis and management of women with early-onset PE. This equals an annual cost saving to the Canadian healthcare system of approximately C$14.39 million.

CONCLUSIONS

The implementation of a first-trimester screening program for PE and early intervention with aspirin in women identified as high risk for early PE has the potential to prevent a significant number of early-onset PE cases with a substantial associated cost saving to the healthcare system in Canada. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Transverse technique: complementary approach to measurement of first-trimester uterine artery Doppler

OBJECTIVES

To define a protocol for the first-trimester assessment of uterine artery pulsatility index (UtA-PI) using the new transverse technique, to evaluate UtA-PI measured using the transverse approach vs that obtained using the conventional sagittal approach and to determine if accelerated onsite training (in both methods) of inexperienced sonographers can achieve reproducible UtA-PI measurements comparable with those obtained by an experienced sonographer.

METHODS

This was a prospective observational study of women with a singleton pregnancy attending for routine combined first-trimester screening at 11 to 13 + 6 weeks' gestation. The study consisted of two parts, each conducted at a different center (Part 1 in Calgary, Canada and Part 2 in Hong Kong). In Part 1, UtA-PI measurements were performed using the transverse and sagittal techniques by four sonographers trained in both methods, in 10 cases each, and measurement indices (PI), time required and subjective difficulty in obtaining satisfactory measurements were compared. The one sample t-test and Wilcoxon signed rank test were used when appropriate. Bland-Altman plots were used to assess measurement agreement, and intraclass correlation coefficient (ICC) was used to evaluate measurement reliability. A target plot was used to assess measures of central tendency and dispersion. In Part 2, one experienced and three inexperienced sonographers prospectively measured UtA-PI using both approaches in 42 and 35 women, respectively. Inexperienced sonographers underwent accelerated onsite training by the experienced sonographer. Measurement approach and sonographer order were on a random basis. ICC, Bland-Altman and Passing-Bablok analyses were performed to assess measurement agreement and reliability and effect of accelerated training.

RESULTS

In Part 1, no difference was observed between the two techniques in mean time to acquire the measurements (118 s for sagittal vs 106 s for transverse; P = 0.38). The four sonographers reported that the transverse technique was subjectively easier to perform (P = 0.04). Bias and ICC for mean UtA-PI between sagittal and transverse measurements were -0.05 (95% limits of agreement, -0.48 to 0.37) and 0.94, respectively. Measurements obtained using the transverse technique after correcting for gestational age were significantly closer to the expected distribution than those obtained using the sagittal technique. In Part 2, there were no significant differences in median UtA-PI measured using the different approaches for both experienced and inexperienced sonographers (P > 0.05 for all sonographers). Mean UtA-PI measurement reliability between approaches was high for the experienced (ICC = 0.92) and inexperienced (ICC > 0.80) sonographers. UtA-PI measurement approaches did not deviate from linearity, while bias ranged from -0.10 to 0.07. The median time required was similar between the techniques (56.1 s for sagittal vs 49.3 s for transverse; P = 0.054).

CONCLUSIONS

This novel transverse approach for the measurement of UtA-PI in the first trimester appears to be comparable with the sagittal approach in terms of reliability, reproducibility and time required, and may be easier to perform. Providing accelerated onsite training can be helpful for improving the reliability of UtA-PI measurements and could potentially facilitate the broad implementation of first-trimester pre-eclampsia screening. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Folic acid supplementation during the preconception period: A systematic review and meta-analysis

Guidelines recommend that women take folic acid supplements in the preconception period to prevent neural tube defects (NTDs) in their offspring. Estimates of adherence to this recommendation across different countries worldwide have not been synthesized. Medline, CINAHL, and EMBASE were systematically searched to identify studies reporting the prevalence of preconception folic acid supplementation. Pooled prevalence estimates for each country (where data were available) were calculated; and differences based on demographic, methodological, and study quality characteristics were examined. Of 3372 titles and abstracts screened, 722 full-texts were reviewed and 105 articles that reported 106 estimates of preconception folic acid supplementation in 34 countries were included. Pooled prevalence estimates were 32-51% in North America, 9-78% in Europe, 21-46% in Asia, 4-34% in the Middle East, 32-39% in Australia/New Zealand, and 0% in Africa. No South American studies were identified. Higher supplementation prevalence was observed in studies that had more highly educated samples, were conducted in fertility clinics, and assessed folic acid use via self-report. Of note, only 32% and 28% of studies reported timing of folic acid use and adherence to folic acid, respectively. Preconception folic acid supplementation is highly variable worldwide and many women may not achieve sufficient folate levels to prevent NTDs. To better understand non-adherence, recommendations for future research include: more explicit reporting of methodology, more detailed assessment of folic acid use, assessment of variables potentially relevant to folic acid use, and surveillance of folic acid use in a greater diversity of countries, especially in the developing world.

A pilot randomized trial of meniscal allograft transplantation versus personalized physiotherapy for patients with a symptomatic meniscal deficient knee compartment

AIMS

Meniscal allograft transplantation is undertaken to improve pain and function in patients with a symptomatic meniscal deficient knee compartment. While case series have shown improvements in patient reported outcome measures (PROMs), its efficacy has not been rigorously evaluated. This study aimed to compare PROMs in patients having meniscal transplantation with those having personalized physiotherapy at 12 months.

PATIENTS AND METHODS

A single-centre assessor-blinded, comprehensive cohort study, incorporating a pilot randomized controlled trial (RCT) was performed on patients with a symptomatic compartment of the knee in which a (sub)total meniscectomy had previously been performed. They were randomized to be treated either with a meniscal allograft transplantation or personalized physiotherapy, and stratified for malalignment of the limb. They entered the preference groups if they were not willing to be randomized. The Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC) score and Lysholm score and complications were collected at baseline and at four, eight and 12 months following the interventions.

RESULTS

A total of 36 patients entered the study; 21 were randomized and 15 chose their treatments. Their mean age was 28 years (range 17 to 46). The outcomes were similar in the randomized and preference groups, allowing pooling of data. At 12 months, the KOOS₄ composite score (mean difference 12, p = 0.03) and KOOS subscales of pain (mean difference 15, p = 0.02) and activities of daily living (mean difference 18, p = 0.005) were significantly superior in the meniscal transplantation group. Other PROMs also favoured this group without reaching statistical significance. There were five complications in the meniscal transplantation and one in the physiotherapy groups.

CONCLUSION

This is the first study to compare meniscal allograft transplantation to non-operative treatment. The results provide the best quality evidence to date of the symptomatic benefits of meniscal allograft transplantation in the short term, but a multicentre RCT is required to investigate this question further. Cite this article: Bone Joint J 2018;100-B:56-63.

Combined effect of toe out gait and high tibial osteotomy on knee adduction moment in patients with varus knee deformity

BACKGROUND

Gait adaptations, including toe out gait, have been proposed as treatments for knee osteoarthritis. The clinical application of toe out gait, however, is unclear. This study aims to identify the changes in Knee adduction moment in varus knee deformity assessing toe out gait as an alternative to high tibial osteotomy, and if any change in dynamic loading persists post operatively, when anatomical alignment is restored.

METHODS

Three-dimensional motion analysis was performed on 17 patients with medial compartment knee osteoarthritis and varus deformity prior to undergoing high tibial osteotomy, 13 patients were assessed post-operatively, and results compared to 13 healthy controls.

FINDINGS

Pre-operatively, there was no significant difference between natural and toe out gait for measures of knee adduction moment. Post high tibial osteotomy, first (2.70 to 1.51% BW·h) and second peak (2.28 to 1.21% BW·h) knee adduction moment were significantly reduced, as was knee adduction angular impulse (1.00 to 0.52% BW·h·s), to a healthy level. Adopting toe out gait post-operatively reduced the second peak further to a level below that of healthy controls.

INTERPRETATION

Increasing the foot progression angle from 20° (natural) to 30° in isolation did not significantly alter the knee adduction moment or angular impulse. This suggests that adopting a toe out gait, in isolation, in an already high natural foot progression angle, is not of benefit. Adopting toe out gait post-operatively, however, resulted in a further reduction in the second peak to below that of the healthy control cohort, however, this may increase lateral compartment load.

Adolescent patellar instability

Patellar instability most frequently presents during adolescence. Congenital and infantile dislocation of the patella is a distinct entity from adolescent instability and measurable abnormalities may be present at birth. In the normal patellofemoral joint an increase in quadriceps angle and patellar height are matched by an increase in trochlear depth as the joint matures. Adolescent instability may herald a lifelong condition leading to chronic disability and arthritis.

Restoring normal anatomy by trochleoplasty, tibial tubercle transfer or medial patellofemoral ligament (MPFL) reconstruction in the young adult prevents further instability. Although these techniques are proven in the young adult, they may cause growth arrest and deformity where the physis is open. A vigorous non-operative strategy may permit delay of surgery until growth is complete. Where non-operative treatment has failed a modified MPFL reconstruction may be performed to maintain stability until physeal closure permits anatomical reconstruction. If significant growth remains an extraosseous reconstruction of the MPFL may impart the lowest risk to the physis. If minor growth remains image intensifier guided placement of femoral intraosseous fixation may impart a small, but acceptable, risk to the physis.

This paper presents and discusses the literature relating to adolescent instability and provides a framework for management of these patients.

Cite this article: Bone Joint J 2017;99-B:159–70.

Neurodevelopmental Outcomes Following Extensive Cardiopulmonary Resuscitation in the Delivery Room for Infants Born &lt;29 Weeks’ Gestational Age

BACKGROUND: Neurodevelopmental outcomes of preterm infants who receive extensive CPR (ECPR), defined as chest compression with or without epinephrine in the delivery room, remain unclear.

OBJECTIVES: To compare the neurodevelopmental outcomes of preterm infants admitted to Canadian NICUs requiring ECPR versus those who did not require ECPR in the delivery room.

DESIGN/METHODS: Preterm infants born at &lt;29 weeks GA between January 1, 2010 and September 30, 2011 and evaluated at CNFUN centers were retrospectively evaluated. The primary outcome was a composite of death or neurodevelopmental impairment (NDI) at 18-21 months CA defined as presence of any one or more of the following: definitive cerebral palsy or Bayley- III cognitive, language, motor scores &lt;85 on any one of the components or hearing impairment or visual impairment. Demographic factors, neurodevelopmental status including Bayley III cognitive, language and motor scores and sensory impairments were compared between the ECPR and the no ECPR group using univariate and multivariate analyses. RESULTS: Of 2488 eligible infants, 197 (7.9%) received ECPR. 83% of surviving infants had follow-up data. Demographic and outcomes data are summarized below in Table 1 and 2 respectively.

Validation of an obstetric comorbidity index in an external population

Objectives

An obstetric comorbidity index has been developed recently with superior performance characteristics relative to general comorbidity measures in an obstetric population. This study aimed to externally validate this index and to examine the impact of including hospitalisation/delivery records only when estimating comorbidity prevalence and discriminative performance of the obstetric comorbidity index.

Design

Validation study.

Setting

Alberta, Canada.

Population

Pregnant women who delivered a live or stillborn infant in hospital (n = 5995).

Methods

Administrative databases were linked to create a population‐based cohort. Comorbid conditions were identified from diagnoses for the delivery hospitalisation, all hospitalisations and all healthcare contacts (i.e. hospitalisations, emergency room visits and physician visits) that occurred during pregnancy and 3 months pre‐conception. Logistic regression was used to test the discriminative performance of the comorbidity index.

Main outcome measures

Maternal end‐organ damage and extended length of stay for delivery.

Results

Although prevalence estimates for comorbid conditions were consistently lower in delivery records and hospitalisation data than in data for all healthcare contacts, the discriminative performance of the comorbidity index was constant for maternal end‐organ damage [all healthcare contacts area under the receiver operating characteristic curve (AUC) = 0.70; hospitalisation data AUC = 0.67; delivery data AUC = 0.65] and extended length of stay for delivery (all healthcare contacts AUC = 0.60; hospitalisation data AUC = 0.58; delivery data AUC = 0.58).

Conclusions

The obstetric comorbidity index shows similar performance characteristics in an external population and is a valid measure of comorbidity in an obstetric population. Furthermore, the discriminative performance of the comorbidity index was similar for comorbidities ascertained at the time of delivery, in hospitalisation data or through all healthcare contacts.

Costs and benefits of non-invasive fetal RhD determination

OBJECTIVE

Non-invasive fetal Rhesus (Rh) D genotyping, using cell-free fetal DNA (cffDNA) in the maternal blood, allows targeted antenatal anti-RhD prophylaxis in unsensitized RhD-negative pregnant women. The purpose of this study was to determine the cost and benefit of this approach as compared to routine antenatal anti-RhD prophylaxis for all unsensitized RhD-negative pregnant women, as is the current policy in the province of Alberta, Canada.

METHODS

This study was a decision analysis based on a theoretical population representing the total number of pregnancies in Alberta over a 1-year period (n = 69 286). A decision tree was created that outlined targeted prophylaxis for unsensitized RhD-negative pregnant women screened for cffDNA (targeted group) vs routine prophylaxis for all unsensitized RhD-negative pregnant women (routine group). Probabilities at each decision point and costs associated with each resource were calculated from local clinical and administrative data. Outcomes measured were cost, number of women sensitized and doses of Rh immunoglobulin (RhIG) administered.

RESULTS

The estimated cost per pregnancy for the routine group was 71.43 compared with 67.20 Canadian dollars in the targeted group. The sensitization rates per RhD-negative pregnancy were equal, at 0.0012, for the current and targeted programs. Implementing targeted antenatal anti-RhD prophylaxis would save 4072 doses (20.1%) of RhIG over a 1-year period in Alberta when compared to the current program.

CONCLUSIONS

These data support the feasibility of a targeted antenatal anti-RhD prophylaxis program, at a lower cost than that of the existing routine prophylaxis program, with no increased risk of sensitization.

The calcium scare--what would Austin Bradford Hill have thought?

Detailed consideration of the suggested association between calcium supplementation and heart attacks has revealed weakness in the evidence which make the hypothesis highly implausible.

INTRODUCTION

The aim of this study was to evaluate the strength of the evidence that calcium supplementation increases the risk of myocardial infarction.

METHODS

This study used critical examination of a meta-analysis of the effects of calcium supplements on heart attacks in five prospective trials on 8,016 men and women, and consideration of related publications by the same author.

RESULTS

The meta-analysis was found to be subject to several limitations including non-adherence to the clinical protocol, multiple endpoint testing and failure to correctly adjust for endpoint ascertainment. The main risk factors for myocardial infarction were not available for 65% of the participants, and none of the trials had cardiovascular disease as its primary endpoint. There were more overweight participants, more subjects on thyroxine and more men on calcium than on placebo. In particular, over 65% of all the heart attacks were self-reported. When the evidence was considered in the light of Austin Bradford Hill's six main criteria for disease causation, it was found not to be biologically plausible or strong or to reflect a dose-response relationship or to be consistent or to reflect the relationship between the trends in calcium supplementation and heart attacks in the community or to have been confirmed by experiment. The addition of a more recent trial on 1,460 women over 5 years reduced the relative risk to 1.23 (P = 0.0695).

CONCLUSION

Present evidence that calcium supplementation increases heart attacks is too weak to justify a change in prescribing habits.

Malreduction of syndesmosis--are we considering the anatomical variation?

Previous studies have demonstrated the need for accurate reduction of ankle syndesmosis. Measurement of syndesmosis is difficult on plain radiographs. A computed tomography (CT) scan allows better visualisation of the transverse relationship between the fibula and incisura fibularis. The difference ('G' a term we coined for ease of description) between the fibula and the anterior and posterior facets of the incisura fibularis was compared between normal and injured ankles following syndesmotic fixation in 19 patients. The mean diastasis (MD) was also calculated, representing the average measurement between the fibula and the anterior and posterior incisura. When compared with the normal side, eight out of 19 (42%) cases were found to have a residual diastasis even after fixation across the syndesmosis. However, if a standard value of G (2mm) was used for the injured leg only, all of the 19 cases would have abnormal values of 'G' following reduction. Our study has clearly demonstrated the need for individualising the assessment method to guide surgeons and radiologists prior to revision surgery. A standard value of 'G' of 2mm as the normal limit cannot be applied universally, as apparent from the data presented in this study.

Factors that influence the childbearing intentions of Canadian men

BACKGROUND

The role of men in the childbearing decision process and the factors that influence men's childbearing intentions have been relatively unexplored in the literature. This study aimed to describe the factors that strongly influence the childbearing intentions of men and to describe differences in these factors according to men's age group.

METHODS

A telephone survey (response rate 84%) was conducted with 495 men between the ages of 20 and 45 living in an urban setting who, at the time of contact, did not have biological children. Men were asked about what factors strongly influence their intention to have children. Univariable and multivariable logistic regressions were conducted to determine if these factors were significantly associated with age.

RESULTS

Of those sampled, 86% of men reported that at some point in the future they planned to become a parent. The factors that men considered to be most influential in their childbearing intentions were: the need to be financially secure, their partner's interest/desire to have children, their partner's suitability to be a parent and their personal interest/desire to have children. Men who were 35–45 years old had lower odds of stating that financial security (crude OR: 0.32, 95% CI: 0.18–0.54) and partner's interest in having children (crude OR: 0.57, 95% CI: 0.33–0.99) were very influential, but had higher odds of stating that their biological clock (crude OR: 4.37, 95% CI: 1.78–10.76) was very influential in their childbearing intentions than men in the 20–24 year age group.

CONCLUSIONS

The factors that influence men's intentions about when to become a parent may change with age. Understanding what influences men to have children, and what they understand about reproductive health is important for education, program and policy development.

General practitioners' attitudes to assessment of genetic risk of common disorders in routine primary care

In 2003, the UK Department of Health set out the genetics white paper, a plan for action and investment with particular emphasis on integration of genetic health care into primary care. Since the delivery of the genetics white paper, there has been little exploration of UK primary care doctors' attitudes towards extending their role to include provision of routine genetics services. We explored explore general practitioners' (GPs) attitudes towards provision of genetic health care including routine family history screening and familial risk assessment for common disorders in primary care using a quantitative, evaluative postal survey. Only 25% (797 of 3160) of the GPs returned a completed questionnaire. Although 32% of GPs supported collection of family history information and 41.5% familial risk assessment, 18% were not willing to offer these services even if training is provided. Of the GPs, 50% stated they recognized when referral to genetics services is appropriate, although 43% felt unprepared to collect family history or assess familial risk. Lack of training within the last 3 years was a significant predictor of feeling unprepared to undertake these activities (OR = 2.53,p = 0.012). A substantial group of GPs remain unprepared or unwilling to provide genetic health care. GPs' attitudes to delivery of genetic health care are significantly influenced by factors such as a lack of evidence of the direct benefits to patients, local guidelines and specialist services. These factors need addressing if delivery of genetic health care is to be incorporated into routine primary care.

Review of Kinemax knee arthroplasty performed at the NHS Treatment Centre, Weston-Super-Mare

As part of the government's initiative to reduce waiting times for major joint surgery in Wales, the Cardiff and Vale NHS Trust sent 224 patients (258 knees) to the NHS Treatment Centre in Weston-Super-Mare for total knee replacement. The Kinemax total knee replacement system was used in all cases. The cumulative survival rate at three years was 79.2% (95% confidence interval (CI) 69.2 to 86.8) using re-operation for any cause as an endpoint and 85.3% (95% CI 75.9 to 91.8) using aseptic revision as an endpoint. This is significantly worse than that recorded in the published literature. These poor results have resulted in a significant impact on our service.

In Vivo Thrombogenicity of Embolic Protection Systems for Angioplasty and Stenting

Despite the increasing use of embolic protection systems (EPS) for carotid stenting, their intrinsic in vivo thrombogenicity remains unknown. We studied three different types of EPS (n = 24) deployed in the carotid arteries of pigs in which pools of platelets and fibrinogen were labelled with 111In and 125I. The amount of clot deposition seen on photography was also scored using a qualitative scale.

EPS made of fabric nets under normal flow conditions were 5–6 and 15–16 times more thrombogenic (for both platelet (P=.04) and fibrin (P=.007)) than Nitinol mesh nets. Clot deposition on Nitinol mesh nets was more abundant under flow arrest than under normal flow conditions (P=.018).

EPS differ in intrinsic thrombogenicity, a characteristic of the material that could be investigated in pre-clinical studies designed to optimize devices.

Implementing a space-time rainfall model for the Sydney region

This paper investigates a Spatial Neyman-Scott Rectangular Pulse (SNSRP) model, which is one of only a few models capable of continuous simulation of rainfall in both space and time. The SNSRP is a spatial extension of the Neyman-Scott Rectangular Pulse model at a single point. The model is highly idealized having six parameters: storm arrival, cell arrival, cell radius, cell lifetime and two cell intensity parameters. A spatial interpolation of the scale parameter is used so that the model can be simulated continuously in space, rather than as a multi-site model. The parameters are calibrated using least-squares fits to statistical moments based on data aggregated to hourly and daily totals. The SNSRP model is calibrated to a very large network of 85 gauges over metropolitan Sydney and shows a good agreement to calibrated statistics. A simulation of 50 replicates over the region compares favourably to several observed temporal statistics, with an example given for one site. A qualitative discussion of the simulated spatial images demonstrates the underlying structure of non-advecting cylindrical cells.

Endoluminal cryotherapy to prevent recanalization after endovascular occlusion with platinum coils

PURPOSE

Endovascular embolization with platinum coils is sometimes followed by recanalization. The present study was undertaken to assess whether cryoablation of the endothelial lining could prevent recanalization after coil occlusion.

MATERIALS AND METHODS

Recanalization rates of canine maxillary and vertebral arteries (n = 20) occluded with platinum coils with or without previous cryoablation (with temperatures of -40 degrees C to -45 degrees C for 90 seconds) were analyzed by angiography immediately and at 1 and 3 months in five animals. Pathologic recanalization and fibrosis was assessed at 3 months with use of a qualitative scoring system. Findings were compared with Mann-Whitney tests.

RESULTS

Recanalization after coil occlusion occurred in 50% and 60% of cases with cryoablation at 1 and 3 months, respectively, compared with 100% without ablation (P = .012 and P= .029). There was no significant difference in pathologic scores (P = .348). The brachial plexus in the vicinity of vertebral arteries was injured by cryotherapy in three animals in which an ipsilateral neurologic deficit developed.

CONCLUSIONS

Cryotherapy was moderately effective in the prevention of recanalization after coil occlusion. Deep nerve injury was excessive with the protocol used in the present study.

Endovascular Treatment with Platinum Coils. Recanalization is Associated with Early Increased von Willebrand Factor mRNA

SUMMARY

Recanalization after coil occlusion is a concern for long-term results of endovascular treatment. Knowledge of molecular events following coil occlusion and recanalization could help design specific strategies to promote permanent occlusion. Platinum coils were implanted into canine maxillary, vertebral or lingual arteries. Coil occlusion (treatment 1), routinely followed by recanalization was compared with two strategies to prevent recanalization: beta radiation using (32)P coils (treatment 2) and endothelial denudation, using an endovascular device, followed by coil occlusion (treatment 3). The evolution of initial complete occlusions was followed by angiography and pathology at three months. Levels of messenger RNA of vWF (von Willebrand factor), SMA (smooth muscle actin), CD14, CD31 (or PECAM-1: Platelet Endothelial Cell Adhesion Molecule-1), PDGFBB (platelet-derived growth factor), TGF-b1 (transforming growth factor), MCP-1 (macrophage chemoattractant protein), Angiopoietins, Metalloproteinases-9, 14 and inhibitors (TIMP- 2, 4) were followed by Reverse Transcription and Polymerase Chain Reaction (RT-PCR). Analyses were performed one, four, seven and 14 days after coiling, and levels of expression after the three treatments were compared using ANOVAs. Intact arteries treated with platinum coils routinely recanalize (100%), but arteries treated by denudation and coiling or with radioactive coils recanalize in only 17% and 4% respectively (P<.001). Recanalization was associated with increased levels of vWF mRNA at seven days, a finding that was not observed with denudation or radiation (P=.015). There was no other significant difference. Recanalization is associated with early vWF expression, perhaps reflecting the development of endothelialized channels through thrombus formed after coil occlusion.

Safety and effectiveness of radioactive coil embolization of aneurysms: effects of radiation on recanalization, clot organization, neointima formation, and surrounding nerves in experimental models

BACKGROUND AND PURPOSE

Recanalization after coil embolization can be prevented by radiation emitted from 32P coils. We wanted to determine the upper limits of 32P activities that could be implanted onto coils with respect to the potential injury to nearby nerves, delay in organization of the clot, and effects on neointima formation and recanalization.

METHODS

We studied the effects of various 32P activities on recanalization and organization of thrombus after coil occlusion of canine arteries and on neointima formation at the neck of canine carotid bifurcation aneurysms. We also tested potential injury to nerves in the vicinity of radioactive or nonradioactive coils in 3 models: the brachial plexus (near proximal vertebral arteries) and the lingual nerve in a lingual artery bifurcation aneurysm model, both models being treated by radioactive or standard coil occlusion. Finally, we wrapped lingual nerves with nonradioactive or high-activity coils and studied their effects on lingual nerves and tongues. Results were assessed with a pathological scoring system and compared with Mann-Whitney and Kruskal-Wallis tests.

RESULTS

No deleterious effect of radiation on nerves could be detected. Neointima formation was not hampered, scores of aneurysms treated with 32P-coils being significantly better when compared with treatments with standard coils (P=0.002). Arteries treated with high-activity coils (>3.39 microCi) showed absent recanalization but delayed organization of the clot at 3 months compared with low-activity or nonradioactive coils (P<0.05).

CONCLUSIONS

beta-Radiation can prevent recanalization after coil occlusion. We could not demonstrate any deleterious effects of radioactivity on nervous structure or on neointima formation. Delayed organization of thrombus provides a rational basis to establish an upper limit for 32P activities to be implanted onto coils.

Production of radioactive particles for endovascular therapeutic interventions

Recanalization is a common phenomenon that decreases the efficacy of embolization procedures. It can be inhibited by beta-radiation. Two novel ways of producing radioactive particles are described, by neutron beam irradiation of gold-containing microspheres, or by using the 32P binding capacity of zirconium-containing microspheres. Particles were tested in vivo, to assess their ability to deliver radioactivity locally, using canine renal artery, porcine rete mirabile, and rabbit ear embolization models. Both radioactive microspheres (198Au and 32P) showed no detectable activity outside the target territory. 32P microspheres demonstrated typical radiation changes in a porcine rete mirabile arteriovenous malformation model.

Endovascular Treatment of Aneurysms: Gene Expression of Neointimal Cells Recruited on the Embolic Agent and Evolution with Recurrence in an Experimental Model

PURPOSE

The authors attempted to identify genes associated with healing or recurrence after embolization in an aneurysm model in which neointima formation at the neck varies according to flow zones. A better understanding of the relationship between blood flow, molecular events, and healing or recurrence may provide future avenues to improve results of endovascular treatment of aneurysms.

METHODS

Bilateral carotid venous pouch aneurysms were constructed in 36 dogs and embolized with gelatin sponges. Angiography and pathological studies were performed at T0 and/or 3 weeks (n=22). Angiographic results and neointima formation were scored using a qualitative index applied to the distal (inflow) and proximal (outflow) zones of the neck. In 14 animals, mRNA expression 1 to 14 days after embolization at the proximal or distal segment of the sponge was analyzed by RT-PCR, attempting to correlate flow zones, gene expression, and neointima formation.

RESULTS

Aneurysms recurred at 3 weeks, as shown by significantly worse angiographic scores as compared to T0 (P<.01). Neointimal scores differed at pathology, with a more complete neointima at the proximal as compared to the distal aspect of the sponge at 3 weeks (P=.027). Embolization was followed by migration of CD31+, CD14+, smooth muscle alpha-actin+ (SMA+) cells that progressively expressed metalloproteinases (MMP-9,-12,-14), but stable or lesser, retarded expression of inhibitors (TIMP1-4). Growth factors (PDGF-BB, TGF-beta1, TNF-alpha, MCP-1 and Ang-1) were expressed at increasing levels, maximal at 7 to 14 days. Differences between distal and proximal zones were limited to increased expression of MMP-2 proximally (P<.035).

CONCLUSION

Gene expression after embolization is compatible with patterns associated with neointima formation. The authors have not identified key factors involved in recurrence.

Temporary vascular occlusion with poloxamer 407

There is a need for safe and reversible occlusions during percutaneous endovascular procedures. Poloxamer 407 is a non-ionic surfactant with rapid reversible sol-gel transition behaviour. The safety and efficacy of this polymer as a temporary embolic agent was investigated. First, dissolution time after gelation of poloxamer was determined in an in vitro model. Then, transient poloxamer occlusion of renal and pulmonary arteries of seven dogs was followed by serial angiograms. Macroscopic and pathological changes were studied 1 week later. This experiment was repeated in similar arteries in one pig, and in auricular arteries of two rabbits. Poloxamer dissolution after in vitro polymerization was completed within 1-20 h, depending on concentrations. In vivo poloxamer 22% injections led to complete occlusion, followed by full recanalization within 10-90 min without complication. The only biochemical effect of poloxamer occlusions was transient elevation of triglyceride levels. There were no pathological abnormalities at 1 week. Poloxamer 407 could be used as an embolic material for temporary occlusions.

Recanalization of arterial thrombus, and inhibition with β-radiation in a new murine carotid occlusion model: mRNA expression of angiopoietins, metalloproteinases, and their inhibitors

BACKGROUND

Recanalization is an important physiologic phenomenon because it can efficiently reestablish circulation after thrombosis. We attempted to characterize molecular events related to recanalization or organization of arterial thrombus in a new murine model by studying genes reported to be involved in angiogenesis or neointima formation.

METHODS

Platinum coils, radioactive phosphorus 32 coils or not, were implanted in the carotid artery in mice to cause thrombotic occlusion. The outcome of the occlusion was followed up with transmyocardial angiography and pathologic analysis at 2, 6, or 15 days. Angiographic results were compared with the Pearson chi2 test. Messenger RNA expression of von Willebrand factor (vWF); smooth muscle alpha-actin (SMA+); platelet endothelial cell adhesion molecule-1 (PECAM-1); vascular endothelium cadherin (VE-Cad); endothelial nitric oxide synthase (eNOS); vascular cell adhesion molecule-1 (VCAM-1); tumor necrosis factor alpha (TNF-alpha); matrix metalloproteinase (MMP-9, MMP-12, and MMP-14), and tissue inhibitors of MMPs (TIMPs: TIMP-1, TIMP-2, TIMP-3, TIMP-4); angiopoietins (Ang-1, Ang-2); and receptors Tie-1 and Tie-2, were analyzed with reverse transcriptase polymerase chain reaction 2, 6, and 15 days after surgery. Levels of mRNA expression were compared with analysis of variance and the Student t test.

RESULTS

Carotid arteries implanted with nonradioactive 0.015-caliber coils were occluded in 84% of arteries on day 2, but in only 57% of arteries on day 15, which confirms that recanalization occurred in this model. Arteries implanted with 0.015-caliber 32P coils did not become recanalized, and 100% were occluded on day 15 (n = 13; P = .006). Recanalization was associated with endothelial-like cell-lined channels, whereas persistent occlusion was caused by complete filling of the lumen with conjunctive tissue. Coil occlusion, with or without recanalization, was followed by decreased expression of vWf, VE-Cad, eNOS, VCAM-1, MMP-2, TIMP-1, and TIMP-2; stable expression of PECAM-1, SMA+, and TIMP-3; and overexpression of Ang-1 and Ang-2, MMP-9, MMP-14, and TIMP-4. Statistically significant differences when arteries were implanted with 32P coils included decreased expression of TIMP-4 (P = .011) and increased expression of MMP-9 (P = .02).

CONCLUSION

Recanalization and organization of arterial thrombus is associated with expression of genes involved in angiogenesis and neointima formation. Recanalization can be prevented with beta-radiation, but molecular mechanisms remain to be refined.

CLINICAL RELEVANCE

A better understanding of molecular mechanisms involved in angiogenesis has permitted its regulation as a new option in treatment of various diseases. Inhibition of angiogenesis may help control diseases such as cancer, arthritis, or diabetes retinopathy. On the other hand, stimulation of angiogenesis may palliate conditions associated with insufficient blood supply, such as ischemic heart disease or critical limb ischemia. Yet little is known regarding recanalization (to be differentiated from thrombolysis), a cellular process that occurs concurrently with thrombus "organization." Recanalization is an important physiologic phenomenon because it can efficiently reestablish antegrade circulation after thrombosis both in veins and in arteries, and could be modulated for therapeutic purposes. Thus our efforts at better understanding of mechanisms involved in recanalization could be used, in addition to its promotion to recover flow after thrombotic occlusions, to prevent its occurrence after endovascular interventions designed to permanently occlude aneurysms.

Transcatheter embolization using degradable crosslinked hydrogels

Therapeutic embolization is the selective transcatheter blockage of blood vessels or diseased vascular structures. The majority of current embolization materials in clinical use are permanent. There are clinical situations however, in which temporary embolization is desired. Degradable hydroxyethyl acrylate (HEA) microspheres have been synthesized. Canine renal arteries and rabbit central auricular arteries were embolized with HEA microspheres, and compared with degradable human serum albumin (HSA) microspheres, and permanent microspheres. HSA and HEA microspheres both achieved temporary occlusions. HSA and HEA microspheres were recanalizated at 1 and 3 weeks, respectively, while arteries occluded with permanent microspheres did not recanalize. All embolic microspheres led to tissue infarction, with the short-term HSA microspheres providing the least damage, and the permanent microspheres leading to extensive damage. Advantages of temporary embolization were not convincingly demonstrated since temporary occlusions still led to tissue infarction.

Lingual artery bifurcation aneurysms for training and evaluation of neurovascular devices

We present a canine lingual artery bifurcation aneurysm and assess its value for training in endovascular techniques and testing new embolic agents. The experimental aneurysm described herein mirrors human bifurcation aneurysms, and with this model, we sought to reproduce endovascular technical difficulties. However, the lesions created in this canine model did not show angiographic or histologic evidence of aneurysmal recurrence. We conclude that this model may be useful for training in endovascular techniques, but because of the lack of sufficient aneurysmal recurrence, it is not suitable for evaluating new embolic agents.

Role of the endothelial lining in recurrences after coil embolization: prevention of recanalization by endothelial denudation

BACKGROUND AND PURPOSE

Endovascular treatment can improve the outcome of patients treated for ruptured intracranial aneurysms as compared with surgical clipping, but angiographic recurrences are frequent. Endothelial denudation before coil embolization may prevent recanalization and improve results of endovascular treatment.

METHODS

We compared angiographic and pathological results 3 months after coil occlusion of paired canine arteries (n=16), with or without previous denudation of the endothelial lining using an endovascular device. The technique was then used to denude the neck of carotid venous pouch bifurcation aneurysms before coil embolization in 8 dogs, and the angiographic evolution at 12 weeks was compared with 7 control aneurysms treated by coiling only. Qualitative scoring systems were used to compare angiographic results with time and neointimal coverage at the neck of aneurysm after necropsy. The evolution of angiographic scores was analyzed using Wilcoxon signed rank tests whereas angiographic and neointimal scores of the 2 groups were compared using the Mann-Whitney test.

RESULTS

All arteries embolized with platinum coils recanalized, whereas most arteries (12/16 or 75%) denuded before coil embolization remained occluded at 3 and 12 weeks (P<0.001). Aneurysms treated with coils without previous denudation tended to recur, with angiographic scores significantly worse at 12 weeks as compared with T(0) (P=0.015). Median angiographic and neointimal scores were significantly better at 12 weeks with endothelial denudation (P=0.011 and 0.026, respectively).

CONCLUSIONS

Endothelial denudation can prevent recanalization after coil embolization.

High-concentration ethylene-vinyl alcohol copolymer and endovascular treatment of experimental aneurysms: feasibility of embolization without protection devices at the neck

BACKGROUND AND PURPOSE

Coiling of intracranial aneurysms is both safe and effective but may be followed by recurrences. The purpose of this study was to assess the feasibility of endovascular treatment of aneurysms with high-concentration ethylene-vinyl alcohol copolymer (HCEVOH), without the use of protection devices at the neck.

METHODS

Wide-necked bifurcation aneurysms with a high propensity for recurrences were constructed in 22 dogs. HCEVOH embolization was performed with a dedicated high-pressure microcatheter in 12 animals. Angiographic results at 3 and 12 weeks and pathologic results at 12 weeks were compared with those of a separate group of 10 animals treated with platinum coils. We used a qualitative scoring system to grade angiographic results, neointima formation, and recanalization at the neck.

RESULTS

Intraaneurysmal HCEVOH injections could be performed without carotid emboli and without a protection device in 11 of 12 animals. Fragments detached upon traction of the microcatheters at the end of the procedure on two occasions. Immediate and late angiographic results were not significantly different between the two groups (P =.807), with a tendency for angiographic recurrences at 3 months (angiographic scores were significantly worse in both groups at 12 weeks as compared with T0 [P <.02]). A complete occlusion, including the neck, even at the cost of protrusion of material at the level of the branches, is necessary to decrease risks of recurrences. Neointima formation at the surface of the embolic agent was complete at the neck of aneurysms treated with HCEVOH. The neointimal score was significantly improved with HCEVOH as compared with coil embolization (P =.03).

CONCLUSION

HCEVOH embolization of aneurysms without neck protection is feasible. It does not, however, eliminate recurrences in an experimental wide-necked aneurysm model.

Alginate for endovascular treatment of aneurysms and local growth factor delivery

BACKGROUND AND PURPOSE

Coil embolization is safe and effective but may be followed by aneurysm recurrence. Our purpose was to explore the use of alginate as a new embolic agent that could deliver growth factors and improve results of endovascular treatment of aneurysms.

METHODS

We first assessed the potential of alginate as a vector for growth factor delivery by using in vitro binding and elution studies. Lateral wall (n = 68) and bifurcation (n = 4) aneurysms were then constructed in six pigs and 36 dogs. We explored iodine-125 transforming growth factor-beta(1) in vivo alginate delivery in 16 canine aneurysms. We next assessed the effects of adding alginate to gelatin sponges on angiographic and pathologic results at 3 weeks (n = 4 each) in an established model used for the study of recanalization and recurrence. We then explored techniques to control endovascular alginate delivery without protection (n = 4), with the protection of a balloon (n = 4), and with the protection of a single coil (n = 12) at the aneurysm neck in 12 porcine aneurysms, four canine lateral wall aneurysms, and four canine bifurcation aneurysms. The stability of cross-linked alginate was studied after intraoperative injections in eight aneurysms. Finally, to determine the value of the material with or without growth factor in promoting aneurysm healing, we compared angiographic results and neointima formation 3 weeks after intraoperative embolization of canine lateral wall aneurysms with alginate blocks with or without platelet-derived growth factor-BB or transforming growth factor-beta(1) (n = 5 each).

RESULTS

Growth factors rapidly eluted from alginate in vitro and in vivo. Alginate coating of sponges led to improved angiographic results and thick neointima formation. Intraoperative alginate block embolization did not lead to recurrence, and growth factors delivered with alginate did not show added benefits. Endovascular alginate embolization was complicated by carotid emboli, and the polymer was unstable once injected, causing delayed neurologic deficits.

CONCLUSION

Growth factor delivery can be performed with alginate, but formulation changes and improved endovascular control are necessary before contemplating its use in intracranial aneurysms.

Cold hibernated elastic memory foams for endovascular interventions

Cold hibernated elastic memory (CHEM) polyurethane-based foam is a new shape memory polymeric self-deployable structure. Standard cytotoxicity and mutagenicity tests were conducted on CHEM in vitro, to ensure biocompatibility before studying potential medical applications. In vivo, lateral wall aneurysms were constructed on both carotid arteries of eight dogs. Aneurysms were occluded per-operatively with CHEM blocks. In two dogs, CHEM embolization was compared with gelatin sponge fragment embolization. Internal maxillary arteries (Imax) were also occluded with CHEM using a 6F transcatheter technique. Angiography and pathology were used to study the evolution of aneurysms and Imax at 3 and 12 weeks. Imax embolized with CHEM foam remained occluded at 3 weeks. Most aneurysms embolized with CHEM showed a small residual crescent of opacification at initial angiography, but angiographic scores were significantly better at 3 weeks. Thick neointima formation over the CHEM at the neck of aneurysms was demonstrated at pathology. The foamy nature of CHEM favours the ingrowth of cells involved in neointima formation. New devices for endovascular interventions could be designed using CHEM's unique physical properties.

[Factors associated with hospital mortality in patients admitted to the intensive care unit in Colombia]

OBJECTIVES

To describe the demographic features, reasons for hospital admission and factors associated with hospital mortality in patients admitted to intensive care in Colombia.

METHOD

A cohort study of patients admitted to intensive care units (ICUs). Of 89 ICUs identified in Colombia, 20 in ten cities were invited to gather information on 200 consecutive patients admitted to each ICU.

RESULTS

Three thousand sixty-six patient cases were available for analysis. The mean age was 53 years and 43% were women (men vs. women, p < 0.001). The most frequent cause of admission was medical (63.9%), acute myocardial infarction patients (7.1%) comprising the largest group. Severity of disease measured as APACHE II and III was a mean 14.0 (SD 6.9) and 48.3 (SD 23.5), respectively. Multivariate analysis, independent of adjustment for severity (APACHE II or III), showed that the factors associated with hospital death were the need for mechanical ventilation, pupillary response, transfer from a medical ward, and management by the ICU team prior to admission (p < 0.01).

CONCLUSION

The most common reason for admission to an ICU in Colombia was myocardial infarction. Besides severity of disease, other variables related to medical care in Colombia are associated with hospital mortality, such as invasive ventilation. Although these variables may be artifacts related to disease severity, they are more likely to be related to quality of care.