Prophylaxis of Thromboembolism in Critical Care (PROTECT) Trial: a pilot study

Evaluating the feasibility of a multicenter teleneonatology clinical effectiveness trial

BACKGROUND

Our research consortium is preparing for a prospective multicenter trial evaluating the impact of teleneonatology on the health outcomes of at-risk neonates born in community hospitals. We completed a 6-month pilot study to determine the feasibility of the trial protocol.

METHODS

Four neonatal intensive care units ("hubs") and four community hospitals ("spokes") participated in the pilot-forming four hub-spoke dyads. Two hub-spoke dyads implemented synchronous, audio-video telemedicine consultations with a neonatologist ("teleneonatology"). The primary outcome was a composite feasibility score that included one point for each of the following: site retention, on-time screening log completion, no eligibility errors, on-time data submission, and sponsor site-dyad meeting attendance (score range 0-5).

RESULTS

For the 20 hub-spoke dyad months, the mean (range) composite feasibility score was 4.6 (4, 5). All sites were retained during the pilot. Ninety percent (18/20) of screening logs were completed on time. The eligibility error rate was 0.2% (3/1809). On-time data submission rate was 88.4% (84/95 case report forms). Eighty-five percent (17/20) of sponsor site-dyad meetings were attended by both hub and spoke site staff.

CONCLUSIONS

A multicenter teleneonatology clinical effectiveness trial is feasible. Learnings from the pilot study may improve the likelihood of success of the main trial.

IMPACT

A prospective, multicenter clinical trial evaluating the impact of teleneonatology on the early health outcomes of at-risk neonates born in community hospitals is feasible. A multidimensional composite feasibility score, which includes processes and procedures fundamental to completing a clinical trial, is useful for quantitatively measuring pilot study success. A pilot study allows the investigative team to test trial methods and materials to identify what works well or requires modification. Learnings from a pilot study may improve the quality and efficiency of the main effectiveness trial.

Targeting the reduction of inflammatory risk associated with cardiovascular disease by treating periodontitis either alone or in combination with a systemic anti-inflammatory agent: protocol for a pilot, parallel group, randomised controlled trial

INTRODUCTION

Cardiovascular disease (CVD) is associated with systemic inflammation. Colchicine, an anti-inflammatory drug, reduces the incidence of CVD events. Periodontitis, a chronic localised inflammatory disease of the tissues supporting the teeth, triggers systemic inflammation and contributes to inflammatory risk. Treatment for periodontitis reduces markers of inflammation, however, there is no evidence on whether an anti-inflammatory medication in combination with periodontal treatment can reduce the inflammatory risk. The aim of this trial is to investigate the effect of periodontal treatment either alone or in combination with an anti-inflammatory agent on inflammation in patients with periodontitis and CVD at 8 weeks.

METHODS AND ANALYSIS

60 participants with moderate-to-severe periodontitis, coronary artery disease and an increased inflammatory risk (>2 mg/L high sensitivity C reactive protein (hsCRP) levels) will be recruited from a tertiary referral hospital in Australia in a parallel design, single blind, randomised controlled trial. Baseline hsCRP levels, lipid profile and periodontal assessment will be completed for each participant before they are randomised in a 1:1:1:1 ratio to one of 4 arms as follows: (group A) periodontal treatment and colchicine; (group B) periodontal treatment only; (group C) colchicine only or (group D) control/delayed periodontal treatment. Periodontal treatment will be provided over three treatment visits, 0.5 mg of colchicine will be provided as a daily tablet. Participants will be followed up at 8 weeks to measure primary and secondary outcomes and complete a follow-up questionnaire. The primary outcome is the difference in hsCRP levels, the secondary outcomes are differences in lipid levels and periodontal parameters and the feasibility measures of recruitment conversion rate, completion rate and the safety and tolerability of the trial.

ETHICS AND DISSEMINATION

The study has been approved by the Western Sydney Local Health District Human Ethics Committee (protocol number 2019/ETH00200). Results will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ACTRN12619001573145.

Improving the adoption of optimal venous thromboembolism prophylaxis in critically ill patients: A process evaluation of a complex quality improvement initiative

PURPOSE

This study evaluated a complex initiative to increase evidence-based use of low molecular weight heparin for venous thromboembolism prophylaxis among adult medical-surgical ICU patients.

MATERIALS AND METHODS

This study included: quantitative survey and interviews. Participants were healthcare providers within four ICUs. Surveys collected knowledge of evidence underpinning best practice, exposure to the implementation strategies and their perceived utility, and recommendations. The interview expanded on survey topics. Descriptive statistics summarized the data and chi-squared tests were used to compare groups. Qualitative data were analyzed using a blended deductive and inductive coding approach.

RESULTS

Providers had good knowledge of the evidence (range = 58% to 94%). Pharmacist-to-physician reminders (80%), other reminders (50%), and local guidelines (50%) were the most commonly observed strategies. Local champions (76%), on-site education (74%), and computerized decision support system (69%) were perceived to be most helpful. Interviews elicited five themes: provider roles, perceptions of the implementation strategies, facilitators and barriers to uptake of best practice, and recommendations. Assessment of the implementation strategies varied by professional group.

CONCLUSIONS

The findings of this process evaluation identified implementation strategies that can improve the use of evidence-informed practices, help interpret outcomes in the context of interventions and guide future quality improvement initiatives.

Harms of off-label erythropoiesis-stimulating agents for critically ill people

BACKGROUND

Anaemia is a common problem experienced by critically-ill people. Treatment with erythropoiesis-stimulating agents (ESAs) has been used as a pharmacologic strategy when the blunted response of endogenous erythropoietin has been reported in critically-ill people. The use of ESAs becomes more important where adverse clinical outcomes of transfusing blood products is a limitation. However, this indication for ESAs is not licensed by regulatory authorities and is called off-label use. Recent studies concern the harm of ESAs in a critical care setting.

OBJECTIVES

To focus on harms in assessing the effects of erythropoiesis-stimulating agents (ESAs), alone or in combination, compared with placebo, no treatment or a different active treatment regimen when administered off-label to critically-ill people.

SEARCH METHODS

We conducted a systematic search of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO via OvidSP, CINAHL, all evidence-based medicine (EBM) reviews including IPA and SCI-Expanded, Conference Proceedings Citation Index- Science, BIOSIS Previews and TOXLINE up to February 2017. We also searched trials registries, checked reference lists of relevant studies and tracked their citations by using SciVerse Scopus.

SELECTION CRITERIA

We considered randomized controlled trials (RCTs) and controlled observational studies, which compared scheduled systemic administration of ESAs versus other effective interventions, placebo or no treatment in critically-ill people.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and evaluated the eligibility of retrieved records, extracted data and assessed the risks of bias and quality of the included studies. We resolved differences in opinion by consensus or by involving a third review author. We assessed the evidence using GRADE and created a 'Summary of findings' table. We used fixed-effect or random-effects models, depending on the heterogeneity between studies. We fitted three-level hierarchical Bayesian models to calculate overall treatment effect estimates.

MAIN RESULTS

Of the 27,865 records identified, 39 clinical trials and 14 observational studies, including a total of 945,240 participants, were eligible for inclusion. Five studies are awaiting classification. Overall, we found 114 adverse events in 33 studies (30 RCTs and three observational studies), and mortality was reported in 41 studies (32 RCTs and nine observational studies). Most studies were at low to moderate risk of bias for harms outcomes. However, overall harm assessment and reporting were of moderate to low quality in the RCTs, and of low quality in the observational studies. We downgraded the GRADE quality of evidence for venous thromboembolism and mortality to very low and low, respectively, because of risk of bias, high inconsistency, imprecision and limitations of study design.It is unclear whether there is an increase in the risk of any adverse events (Bayesian risk ratio (RR) 1.05, 95% confidence interval (CI) 0.93 to 1.21; 3099 participants; 9 studies; low-quality evidence) or venous thromboembolism (Bayesian RR 1.04, 95% CI 0.70 to 1.41; 18,917 participants; 18 studies; very low-quality evidence).There was a decreased risk of mortality with off-label use of ESAs in critically-ill people (Bayesian RR 0.76, 95% CI 0.61 to 0.92; 930,470 participants; 34 studies; low-quality evidence).

AUTHORS' CONCLUSIONS

Low quality of evidence suggests that off-label use of ESAs may reduce mortality in a critical care setting. There was a lack of high-quality evidence about the harm of ESAs in critically-ill people. The information for biosimilar ESAs is less conclusive. Most studies neither evaluated ESAs' harm as a primary outcome nor predefined adverse events. Any further studies of ESA should address the quality of evaluating, recording and reporting of adverse events.

Unfractionated heparin versus low molecular weight heparins for avoiding heparin-induced thrombocytopenia in postoperative patients

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction presenting as a prothrombotic disorder related to antibody-mediated platelet activation. It is a paradoxical immune reaction resulting in thrombin generation in vivo, which leads to a hypercoagulable state and the potential to initiate venous or arterial thrombosis. A number of factors are thought to influence the incidence of HIT including the type and preparation of heparin (unfractionated heparin (UFH) or low molecular weight heparin (LMWH)) and the heparin-exposed patient population, with the postoperative patient population at higher risk.Although LMWH has largely replaced UFH as a front-line therapy, there is evidence supporting a lack of superiority of LMWH compared with UFH regarding prevention of deep vein thrombosis and pulmonary embolism following surgery, and similar frequencies of bleeding have been described with LMWH and UFH. The decision as to which of these two preparations of heparin to use may thus be influenced by harmful effects such as HIT. We therefore sought to determine the relative impact of UFH and LMWH on HIT in postoperative patients receiving thromboembolism prophylaxis. This is an update of a review first published in 2012.

OBJECTIVES

The objective of this review was to compare the incidence of heparin-induced thrombocytopenia (HIT) and HIT complicated by venous thromboembolism in postoperative patients exposed to unfractionated heparin (UFH) versus low molecular weight heparin (LMWH).

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Specialised Register (May 2016), CENTRAL (2016, Issue 4) and trials registries. The authors searched Lilacs (June 2016) and additional trials were sought from reference lists of relevant publications.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which participants were postoperative patients allocated to receive prophylaxis with UFH or LMWH, in a blinded or unblinded fashion. Studies were excluded if they did not use the accepted definition of HIT. This was defined as a relative reduction in the platelet count of 50% or greater from the postoperative peak (even if the platelet count at its lowest remained greater than 150 x 109/L) occurring within five to 14 days after the surgery, with or without a thrombotic event occurring in this timeframe. Additionally, we required circulating antibodies associated with the syndrome to have been investigated through laboratory assays.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias. Disagreements were resolved by consensus with participation of a third author.

MAIN RESULTS

In this update, we included three trials involving 1398 postoperative participants. Participants were submitted to general surgical procedures, minor and major, and the minimum mean age was 49 years. Pooled analysis showed a significant reduction in the risk of HIT with LMWH compared with UFH (risk ratio (RR) 0.23, 95% confidence interval (CI) 0.07 to 0.73); low-quality evidence. The number needed to treat for an additional beneficial outcome (NNTB) was 59. The risk of HIT was consistently reduced comparing participants undergoing major surgical procedures exposed to LMWH or UFH (RR 0.22, 95% CI 0.06 to 0.75); low-quality evidence. The occurrence of HIT complicated by venous thromboembolism was significantly lower in participants receiving LMWH compared with UFH (RR 0.22, 95% CI 0.06 to 0.84); low-quality evidence. The NNTB was 75. Arterial thrombosis occurred in only one participant who received UFH. There were no amputations or deaths documented. Although limited evidence is available, it appears that HIT induced by both types of heparins is common in people undergoing major surgical procedures (incidence greater than 1% and less than 10%).

AUTHORS' CONCLUSIONS

This updated review demonstrated low-quality evidence of a lower incidence of HIT, and HIT complicated by venous thromboembolism, in postoperative patients undergoing thromboprophylaxis with LMWH compared with UFH. Similarily, the risk of HIT in people undergoing major surgical procedures was lower when treated with LMWH compared to UFH (low-quality evidence). The quality of the evidence was downgraded due to concerns about the risk of bias in the included studies and imprecision of the study results. These findings may support current clinical use of LMWH over UFH as front-line heparin therapy. However, our conclusions are limited and there was an unexpected paucity of RCTs including HIT as an outcome. To address the scarcity of clinically-relevant information on HIT, HIT must be included as a core harmful outcome in future RCTs of heparin.

Does Obesity Predispose Medical Intensive Care Unit Patients to Venous Thromboembolism despite Prophylaxis? A Retrospective Chart Review

Background. Obesity is a significant issue in the critically ill population. There is little evidence directing the dosing of venous thromboembolism (VTE) prophylaxis within this population. We aimed to determine whether obesity predisposes medical intensive care unit patients to venous thromboembolism despite standard chemoprophylaxis with 5000 international units of subcutaneous heparin three times daily. Results. We found a 60% increased risk of venous thromboembolism in the body mass index (BMI) ≥ 30 kg/m² group compared to the BMI < 30 kg/m² group; however, this difference did not reach statistical significance. After further utilizing our risk model, neither obesity nor mechanical ventilation reached statistical significance; however, vasopressor administration was associated with a threefold risk. Conclusions. We can conclude that obesity did increase the rate of VTE, but not to a statistically significant level in this single center medical intensive care unit population.

CONSORT 2010 statement: extension to randomised pilot and feasibility trials

The Consolidated Standards of Reporting Trials (CONSORT) statement is a guideline designed to improve the transparency and quality of the reporting of randomised controlled trials (RCTs). In this article we present an extension to that statement for randomised pilot and feasibility trials conducted in advance of a future definitive RCT. The checklist applies to any randomised study in which a future definitive RCT, or part of it, is conducted on a smaller scale, regardless of its design (eg, cluster, factorial, crossover) or the terms used by authors to describe the study (eg, pilot, feasibility, trial, study). The extension does not directly apply to internal pilot studies built into the design of a main trial, non-randomised pilot and feasibility studies, or phase II studies, but these studies all have some similarities to randomised pilot and feasibility studies and so many of the principles might also apply. The development of the extension was motivated by the growing number of studies described as feasibility or pilot studies and by research that has identified weaknesses in their reporting and conduct. We followed recommended good practice to develop the extension, including carrying out a Delphi survey, holding a consensus meeting and research team meetings, and piloting the checklist. The aims and objectives of pilot and feasibility randomised studies differ from those of other randomised trials. Consequently, although much of the information to be reported in these trials is similar to those in randomised controlled trials (RCTs) assessing effectiveness and efficacy, there are some key differences in the type of information and in the appropriate interpretation of standard CONSORT reporting items. We have retained some of the original CONSORT statement items, but most have been adapted, some removed, and new items added. The new items cover how participants were identified and consent obtained; if applicable, the prespecified criteria used to judge whether or how to proceed with a future definitive RCT; if relevant, other important unintended consequences; implications for progression from pilot to future definitive RCT, including any proposed amendments; and ethical approval or approval by a research review committee confirmed with a reference number. This article includes the 26 item checklist, a separate checklist for the abstract, a template for a CONSORT flowchart for these studies, and an explanation of the changes made and supporting examples. We believe that routine use of this proposed extension to the CONSORT statement will result in improvements in the reporting of pilot trials. Editor's note: In order to encourage its wide dissemination this article is freely accessible on the BMJ and Pilot and Feasibility Studies journal websites.

Erythropoietin in traumatic brain injury (EPO-TBI): a double-blind randomised controlled trial

BACKGROUND

Erythropoietin might have neurocytoprotective effects. In this trial, we studied its effect on neurological recovery, mortality, and venous thrombotic events in patients with traumatic brain injury.

METHODS

Erythropoietin in Traumatic Brain Injury (EPO-TBI) was a double-blind, placebo-controlled trial undertaken in 29 centres (all university-affiliated teaching hospitals) in seven countries (Australia, New Zealand, France, Germany, Finland, Ireland, and Saudi Arabia). Within 24 h of brain injury, 606 patients were randomly assigned by a concealed web-based computer-generated randomisation schedule to erythropoietin (40,000 units subcutaneously) or placebo (0·9% sodium chloride subcutaneously) once per week for a maximum of three doses. Randomisation was stratified by severity of traumatic brain injury (moderate vs severe) and participating site. With the exception of designated site pharmacists, the site dosing nurses at all sites, and the pharmacists at the central pharmacy in France, all study personnel, patients, and patients' relatives were masked to treatment assignment. The primary outcome, assessed at 6 months by modified intention-to-treat analysis, was improvement in the patients' neurological status, summarised as a reduction in the proportion of patients with an Extended Glasgow Outcome Scale (GOS-E) of 1-4 (death, vegetative state, and severe disability). Two equally spaced preplanned interim analyses were done (after 202 and 404 participants were enrolled). This study is registered with ClinicalTrials.gov, number NCT00987454.

FINDINGS

Between May 3, 2010, and Nov 1, 2014, 606 patients were enrolled and randomly assigned to erythropoietin (n=308) or placebo (n=298). Ten of these patients (six in the erythropoietin group and four in the placebo group) were lost to follow up at 6 months; therefore, data for the primary outcome analysis was available for 596 patients (302 in the erythropoietin group and 294 in the placebo group). Compared with placebo, erythropoietin did not reduce the proportion of patients with a GOS-E level of 1-4 (134 [44%] of 302 patients in the erythropoietin group vs 132 [45%] of 294 in the placebo group; relative risk [RR] 0·99 [95% CI 0·83-1·18], p=0·90). In terms of safety, erythropoietin did not significantly affect 6-month mortality versus placebo (32 [11%] of 305 patients had died at 6 months in the erythropoietin group vs 46 [16%] of 297 [16%] in the placebo group; RR 0·68 [95% CI 0·44-1·03], p=0·07) or increase the occurrence of deep venous thrombosis of the lower limbs (48 [16%] of 305 vs 54 [18%] of 298; RR 0·87 [95% CI 0·61-1·24], p=0·44).

INTERPRETATION

Following moderate or severe traumatic brain injury, erythropoietin did not reduce the number of patients with severe neurological dysfunction (GOS-E level 1-4) or increase the incidence of deep venous thrombosis of the lower limbs. The effect of erythropoietin on mortality remains uncertain.

FUNDING

The National Health and Medical Research Council and the Transport Accident Commission.

The Perception of Evidence for Venous Thromboembolism Prophylaxis Current Practices after Cardiac Surgery: A Canadian Cross-Sectional Survey

Background. Venous thromboembolism (VTE) is the third leading cause of cardiovascular death in patients undergoing surgery. However, VTE prophylaxis practices in cardiac surgery are based on noncardiac surgical literature. The objective of our study was to extract current patterns of VTE prophylaxis practices in cardiac surgery patients. We also aimed to identify health care professionals knowledge of available evidence supporting VTE prophylaxis in adult cardiac surgery patients. Methods. A web-based survey was developed and sent to all Canadian cardiac surgery centers with the intent to have the survey distributed to all personnel involved in the perioperative care of adult cardiac surgery patients. Participation in the questionnaire was voluntary and anonymized. Results. Thirty-five responses were obtained. Sixty-nine percent reported having an established protocol for VTE prophylaxis. However, 83% reported using VTE prophylaxis in their daily practice despite lack of protocol. The majority (60%) believed that the class of recommendation was high despite the lack of evidence. Conclusions. Our survey demonstrated the following. (a) Majority of Canadian centers employ VTE prophylaxis, with considerable variability. (b) There is a misconception among health care professionals about the strength of evidence supporting VTE prophylaxis in cardiac surgery. Our findings highlight the need for appropriately designed studies to fill this knowledge gap.

Preliminary inconclusive results of a randomised double blinded cross-over pilot trial in long-term-care dwelling elderly assessing the feasibility of stochastic resonance whole-body vibration

Background

This randomised double-blinded controlled cross-over pilot study examined feasibility and preliminary effects of stochastic resonance whole-body vibration training applied in long term care elderly.

Findings

Nine long term care elderly were recruited and randomized to group A (6 Hz, Noise 4 SR-WBV/ Sham) or B (Sham / 1 Hz, Noise 1 SR-WBV). Feasibility outcomes included recruitment rate, attrition, adherence and safety. Physical performance outcomes focused on the Expanded Timed Get Up-and-Go (ETGUG) test, the Short Physical Performance Battery (SPPB), and lower extremity muscle strength.

Of 24 subjects initially approached 9 started and 5 completed the study resulting in 37.5 recruitment, 44.4 attrition and 81.7 % adherence rates. No adverse events were reported. There is more evidence of improved performance levels in the SR-WBV treatment group with significant differences in average change for isometric rate of force development (p = 0.016 left leg; p = 0.028 right leg). No statistical significance was reached for other parameters.

Conclusions

The findings of this study indicate that the used training protocol for long term care elderly is feasible, however, requires more closely monitoring of participants; e.g. needs protocol modifications that target improved compliance with the intervention in this setting. SR-WBV shows beneficial effects on physical performance for those adhering to the intervention.

Trial registration

U.S. National Institutes of Health NCT01543243

Electronic supplementary material

The online version of this article (doi:10.1186/s11556-015-0150-y) contains supplementary material, which is available to authorized users.

Mindfulness-based cognitive therapy for inflammatory bowel disease patients: findings from an exploratory pilot randomised controlled trial

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic gastrointestinal condition with a relapsing disease course. Managing the relapsing nature of the disease causes daily stress for IBD patients; thus, IBD patients report higher rates of depression and anxiety than the general population. Mindfulness-based Cognitive Therapy (MBCT) is an evidence-based psychological program designed to help manage depressive and stress symptoms. There has been no randomized controlled trial (RCT) testing the use of MBCT in IBD patients. The purpose of this pilot study is to test the trial methodology and assess the feasibility of conducting a large RCT testing the effectiveness of MBCT in IBD.

METHODS

The IBD patients, who were recruited from gastroenterology outpatient clinics at two Scottish NHS Boards, were randomly allocated to an MBCT intervention group (n = 22) or a wait-list control group (n = 22). The MBCT intervention consisted of 16 hours of structured group training over 8 consecutive weeks plus guided home practice and follow-up sessions. The wait-list group received a leaflet entitled 'Staying well with IBD'. All participants completed a baseline, post-intervention and 6-month follow up assessment. The key objectives were to assess patient eligibility and recruitment/dropout rate, to calculate initial estimates of parameters to the proposed outcome measures (depression, anxiety, disease activity, dispositional mindfulness and quality of life) and to estimate sample size for a future large RCT.

RESULTS

In total, 350 patients were assessed for eligibility. Of these, 44 eligible patients consented to participate. The recruitment rate was 15%, with main reasons for ineligibility indicated as follows: non-response to invitation, active disease symptoms, planned surgery or incompatibility with group schedule. There was a higher than expected dropout rate of 44%. Initial estimates of parameters to the proposed outcomes at post-intervention and follow-up showed a significant improvement of scores in the MBCT group when compared to the control for depression, trait anxiety and dispositional mindfulness. The sample-size calculation was guided by estimates of clinically important effects in depression scores.

CONCLUSIONS

This pilot study suggests that a multicentre randomized clinical trial testing the effectiveness of MBCT for IBD patients is feasible with some changes to the protocol. Improvement in depression, trait anxiety and dispositional mindfulness scores are promising when coupled with patients reporting a perceived improvement of their quality of life.

TRIAL REGISTRATION

ISRCTN27934462. 2 August 2013.

Feasibility and effects of applying stochastic resonance whole-body vibration on untrained elderly: a randomized crossover pilot study

Background

Aging is associated with loss of balance and activity in daily life. It impacts postural control and increases the risk of falls. The current study was conducted to determine the feasibility and long-term impact of stochastic resonance whole-body vibration (SR-WBV) on static and dynamic balance and reaction time among elderly individuals.

Methods

A randomized crossover pilot study with blinding of the participants. Twenty elderly were divided into group A (SR-WBV 5 Hz, Noise 4/SR-WBV 1 Hz, Noise 1) or group B (SR-WBV 1 Hz, Noise 1/SR-WBV 5 Hz, Noise 1). Feasibility outcomes included recruitment, compliance and safety. Secondary outcomes were Semi-Tandem Stand (STS), Functional Reach Test (FRT), Expanded Timed Get Up-and-Go (ETGUG), walking under single (ST) & dual task (DT) conditions, hand and foot reaction time (RTH/RTF). Puri and Sen Rank-Order L Statistics were used to analyse carry-over effects. To analyse SR-WBV effects Wilcoxon signed-ranked tests were used.

Results

With good recruitment rate (55%) and compliance (attrition 15%; adherence 85%) rates the intervention was deemed feasible. Three participants dropped out, two due to knee pain and one for personal reasons. ETGUG 0 to 2 m (p = 0.143; ES: 0.36) and ETGUG total time (p = 0.097; ES: 0.40) showed medium effect sizes.

Conclusions

Stochastic resonance training is feasible in untrained elderly resulting in good recruitment and compliance. Low volume SR-WBV exercises over 12 training sessions with 5 Hz, Noise 4 seems a sufficient stimulus to improve ETGUG total time. The stimulation did not elicit changes in other outcomes.

Trial registration

This trial has been registered at the U.S. National Institutes of Health under ClinicalTrials.gov: NCT01045746.

Erythropoietin in traumatic brain injury: study protocol for a randomised controlled trial

BACKGROUND

Traumatic brain injury is a leading cause of death and disability worldwide. Laboratory and clinical studies demonstrate a possible beneficial effect of erythropoietin in improving outcomes in the traumatic brain injury cohort. However, there are concerns regarding the association of erythropoietin and thrombosis in the critically ill. A large-scale, multi-centre, blinded, parallel-group, placebo-controlled, randomised trial is currently underway to address this hypothesis.

METHODS/DESIGN

The erythropoietin in traumatic brain injury trial is a stratified prospective, multi-centre, randomised, blinded, parallel-group, placebo-controlled phase III trial. It aims to determine whether the administration of erythropoietin compared to placebo improves neurological outcome in patients with moderate or severe traumatic brain injury at six months after injury. The trial is designed to recruit 606 patients between 15 and 65 years of age with severe (Glasgow Coma Score: 3 to 8) or moderate (Glasgow Coma Score: 9 to 12) traumatic brain injury in Australia, New Zealand, Kingdom of Saudi Arabia, France, Finland, Germany and Ireland. Trial patients will receive either subcutaneous erythropoietin or placebo within 24 hours of injury, and weekly thereafter for up to three doses during the intensive care unit admission. The primary outcome will be the combined proportion of unfavourable neurological outcomes at six months: severe disability or death. Secondary outcomes will include the rate of proximal deep venous thrombosis detected by compression Doppler ultrasound, six-month mortality, the proportion of patients with composite vascular events (deep venous thrombosis, pulmonary embolism, myocardial infarction, cardiac arrest and cerebrovascular events) at six months and quality of life with health economic evaluations.

DISCUSSION

When completed, the trial aims to provide evidence on the efficacy and safety of erythropoietin in traumatic brain injury patients, and to provide clear guidance for clinicians in their management of this devastating condition.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials registry: ACTRN12609000827235 (registered on 22 September 2009). Clinicaltrials.gov: NCT00987454 (registered on 29 September 2009). European Drug Regulatory Authorities Clinical Trials: 2011-005235-22 (registered on 18 January 2012).

Novel technologies can provide effective dressing and securement for peripheral arterial catheters: A pilot randomised controlled trial in the operating theatre and the intensive care unit

BACKGROUND

Peripheral arterial catheters are widely used in the care of intensive care patients for continuous blood pressure monitoring and blood sampling, yet failure - from dislodgement, accidental removal, and complications of phlebitis, pain, occlusion and infection - is common. While appropriate methods of dressing and securement are required to reduce these complications that cause failure, few studies have been conducted in this area.

OBJECTIVES

To determine initial effectiveness of one dressing and two securement methods versus usual care, in minimising failure in peripheral arterial catheters. Feasibility objectives were considered successful if 90/120 patients (75%) received the study intervention and protocol correctly, and had ease and satisfaction scores for the study dressing and securement devices of ≥ 7 on Numerical Rating Scale scores 1-10.

METHODS

In this single-site, four-arm, parallel, pilot randomised controlled trial, patients with arterial catheters, inserted in the operating theatre and admitted to the intensive care unit postoperatively, were randomly assigned to either one of the three treatment groups (bordered polyurethane dressing (n=30); a sutureless securement device (n=31); tissue adhesive (n=32)), or a control group (usual practice polyurethane dressing (not bordered) (n=30)).

RESULTS

One hundred and twenty-three patients completed the trial. The primary outcome of catheter failure was 2/32 (6.3%) for tissue adhesive, 4/30 (13.3%) for bordered polyurethane, 5/31 (16.1%) for the sutureless securement device, and 6/30 (20%) for the control usual care polyurethane. Feasibility criteria were fulfilled. Cost analysis suggested that tissue adhesive was the most cost effective.

CONCLUSIONS

The pilot trial showed that the novel technologies were at least as effective as the present method of a polyurethane dressing for dressing and securement of arterial catheters, and may be cost effective. The trial also provided evidence that a larger, multicentre trial would be feasible.

Economic evaluation of the prophylaxis for thromboembolism in critical care trial (E-PROTECT): study protocol for a randomized controlled trial

Background

Venous thromboembolism (VTE) is a common complication of critical illness with important clinical consequences. The Prophylaxis for ThromboEmbolism in Critical Care Trial (PROTECT) is a multicenter, blinded, randomized controlled trial comparing the effectiveness of the two most common pharmocoprevention strategies, unfractionated heparin (UFH) and low molecular weight heparin (LMWH) dalteparin, in medical-surgical patients in the intensive care unit (ICU). E-PROTECT is a prospective and concurrent economic evaluation of the PROTECT trial.

Methods/Design

The primary objective of E-PROTECT is to identify and quantify the total (direct and indirect, variable and fixed) costs associated with the management of critically ill patients participating in the PROTECT trial, and, to combine costs and outcome results to determine the incremental cost-effectiveness of LMWH versus UFH, from the acute healthcare system perspective, over a data-rich time horizon of ICU admission and hospital admission. We derive baseline characteristics and probabilities of in-ICU and in-hospital events from all enrolled patients. Total costs are derived from centers, proportional to the numbers of patients enrolled in each country. Direct costs include medication, physician and other personnel costs, diagnostic radiology and laboratory testing, operative and non-operative procedures, costs associated with bleeding, transfusions and treatment-related complications. Indirect costs include ICU and hospital ward overhead costs. Outcomes are the ratio of incremental costs per incremental effects of LMWH versus UFH during hospitalization; incremental cost to prevent a thrombosis at any site (primary outcome); incremental cost to prevent a pulmonary embolism, deep vein thrombosis, major bleeding event or episode of heparin-induced thrombocytopenia (secondary outcomes) and incremental cost per life-year gained (tertiary outcome). Pre-specified subgroups and sensitivity analyses will be performed and confidence intervals for the estimates of incremental cost-effectiveness will be obtained using bootstrapping.

Discussion

This economic evaluation employs a prospective costing methodology concurrent with a randomized controlled blinded clinical trial, with a pre-specified analytic plan, outcome measures, subgroup and sensitivity analyses. This economic evaluation has received only peer-reviewed funding and funders will not play a role in the generation, analysis or decision to submit the manuscripts for publication.

Trial registration

Clinicaltrials.gov Identifier: NCT00182143. Date of registration: 10 September 2005.

Electronic supplementary material

The online version of this article (doi:10.1186/1745-6215-15-502) contains supplementary material, which is available to authorized users.

Physicians declining patient enrollment in a critical care trial: a case study in thromboprophylaxis

PURPOSE

To analyze the frequency, rationale and determinants of attending physicians requesting that their eligible patients not be approached for participation in a thromboprophylaxis trial.

METHODS

Research personnel in 67 centers prospectively documented eligible non-randomized patients due to physicians declining to allow their patients to be approached.

RESULTS

In 67 centers, 3,764 patients were enrolled, but 1,460 eligible patients had no consent encounter. For 218 (14.9 %) of these, attending physicians requested that their patients not be approached. The most common reasons included a high risk of bleeding (31.2 %) related to fear of heparin bioaccumulation in renal failure, the presence of an epidural catheter, peri-operative status or other factors; specific preferences for thromboprophylaxis (12.4 %); morbid obesity (9.6 %); uncertain prognosis (6.4 %); general discomfort with research (3.7 %) and unclear reasons (17.0 %). Physicians were more likely to decline when approached by less experienced research personnel; considering those with[10 years of experience as the reference category, the odds ratios (OR) for physician refusals to personnel without trial experience was 10.47 [95 % confidence interval (CI) 2.19-50.02] and those with less than 10 years experience was 1.72 (95 % CI 0.61-4.84). Physicians in open rather than closed units were more likely to decline (OR 4.26; 95 % CI 1.27-14.34). Refusals decreased each year of enrollment compared to the pilot phase.

CONCLUSIONS

Tracking, analyzing, interpreting and reporting the rates and reasons for physicians declining to allow their patients to be approached for enrollment provides insights into clinicians' concerns and attitudes to trials. This information can encourage physician communication and education, and potentially enhance efficient recruitment.

Ultra minimally invasive sonographically guided carpal tunnel release: an external pilot study

BACKGROUND

Authors have reported better outcomes, by reducing surgical dissection for carpal tunnel syndromes requiring surgery. Recently, a new sonographically guided technique for ultra minimally invasive (Ultra-MIS) carpal tunnel release (CTR) through 1mm incision has been described.

HYPOTHESIS

We hypothesized that a clinical trial for comparing Ultra-MIS versus Mini-open Carpal Tunnel Release (Mini-OCTR) was feasible.

MATERIALS AND METHODS

To test our hypothesis, we conducted a pilot study for studying Ultra-MIS versus Mini-OCTR respectively performed through a 1mm or a 2 cm incision. We defined success if primary feasibility objectives (safety and efficacy) as well as secondary feasibility objectives (recruitment rates, compliance, completion, treatment blinding, personnel resources and sample size calculation for the clinical trial) could be matched. Score for Quick-DASH questionnaire at final follow-up was studied as the primary variable for the clinical trial. Turnover times were studied for assessing learning curve stability.

RESULTS

Forty patients were allotted. Primary and secondary feasibility objectives were matched with the following occurrences: 70.2% of eligible patients finally recruited; 4.2% of randomization refusals; 26.6 patients/month recruited; 100% patients receiving a blinded treatment; 97.5% compliance and 100% completion. A sample size of 91 patients was calculated for clinical trial validation. At final follow-up, preliminary results for Quick-Dash substantially favored Ultra-MIS over Mini-OCTR (average 14.54 versus 7.39) and complication rates were lower for Ultra-MIS (5% versus 20%). A stable learning curve was observed for both groups.

CONCLUSIONS

The clinical trial is feasible. There is currently no evidence to contraindicate nor withhold the use of Ultra-MIS for CTR.

LEVEL OF EVIDENCE

III.

[Prevention of venous thromboembolic disease in the critical patient: an assessment of clinical practice in the Community of Madrid]

OBJECTIVE

To analyze measures referred to venous thromboembolic prophylaxis in critically ill patients.

DESIGN

An epidemiological, cross-sectional (prevalence cut), multicenter study was performed using an electronic survey. Comparison of results with quality indexes of the Spanish Society of Intensive Care Medicine, the American College of Chest Physician guidelines and international studies.

SETTING

Intensive Care Units (ICUs) in the Community of Madrid (Spain).

PATIENTS

All patients admitted to the ICU on the day of the survey.

VARIABLES OF INTEREST

General aspects of venous thromboembolic prophylaxis and protocols used (risk stratification and ultrasound screening). A descriptive analysis was performed, continuous data being expressed as the mean or median, and categorical data as percentages.

RESULTS

A total of 234 patients in 18 ICUs were included. Eighteen percent (42/234) received no prophylaxis, and 55% had no contraindication to pharmacological prophylaxis. Of the 192 patients receiving prophylaxis, 84% received pharmacological prophylaxis, 14% mechanical prophylaxis and 2% combined prophylaxis. Low molecular weight heparin was the only pharmacological prophylaxis used, with a majority use of enoxaparin (17 of 18 ICUs). In patients with mechanical prophylaxis (31/192), antiembolic stockings were the most commonly used option (58%). Pharmacological prophylaxis contraindications were reported in 20% of the patients (46/234), the most frequent cause being thrombocytopenia (28% of the cases). Fifty percent of the ICUs used no specific venous thromboembolic prophylaxis protocol.

CONCLUSIONS

Pharmacological prophylaxis with low molecular weight heparin was the most frequently used venous thromboembolic prophylactic measure. In patients with contraindications to pharmacological prophylaxis, mechanical measures were little used. The use of combined prophylaxis was anecdotal. Many of our ICUs lack specific prophylaxis protocols.

Enhancing the informed consent process for critical care research: strategies from a thromboprophylaxis trial

BACKGROUND

Critically ill patients lack capacity for decisions about research participation. Consent to enrol these patients in studies is typically obtained from substitute decision-makers.

OBJECTIVE

To present strategies that may optimise the process of obtaining informed consent from substitute decision-makers for participation of critically ill patients in trials. We use examples from a randomised trial of heparin thromboprophylaxis in the intensive care unit (PROTECT, clinicaltrials.gov NCT00182143).

METHODS

3764 patients were randomised, with an informed consent rate of 82%; 90% of consents were obtained from substitute decision-makers. North American PROTECT research coordinators attended three meetings to discuss enrolment: (1) Trial start-up (January 2006); (2) Near trial closure (January 2010); and (3) Post-publication (April 2011). Data were derived from slide presentations, field notes from break-out groups and plenary discussions, then analysed inductively.

RESULTS

We derived three phases for the informed consent process: (1) Preparation for the Consent Encounter; (2) The Consent Encounter; and (3) Follow-up to the Consent Encounter. Specific strategies emerged for each phase: Phase 1 (four strategies); Phase 2 (six strategies); and Phase 3 (three strategies).

CONCLUSION

We identified 13 strategies that may improve the process of obtaining informed consent from substitute decision-makers and be generalisable to other settings and studies.

Implementing a palliative care trial in advanced COPD: a feasibility assessment (the COPD IMPACT study)

BACKGROUND

Patients and caregivers living with advanced chronic obstructive pulmonary disease (COPD) have complex care needs and may benefit from palliative care intervention. Little is known about how best to implement and evaluate such initiatives.

OBJECTIVES

To determine the feasibility of: 1) implementing a customized home-based palliative care service for patients and caregivers living with advanced COPD and 2) measuring outcomes of providing such services.

DESIGN

Single-centre cohort longitudinal observational study.

SETTING/SUBJECTS

Patients with advanced COPD and their caregivers were followed in their homes for 6 months.

MEASUREMENTS

Health-related quality of life (HRQoL), caregiver burden, symptom severity, patient/caregiver satisfaction, utilization of acute care services, end-of-life (EOL) outcomes.

RESULTS

30 patients and 18 caregivers were enrolled over 33 months. 25 patients (83%) and 14 caregivers (77%) reached our study endpoint. 13 patients (52%) and 5 caregivers (36%) completed outcome measurements at baseline and endpoint. HRQoL, caregiver burden and symptom severity did not change. Palliative care services were welcomed and valued, yet, despite a stated preference to die at home, 16 patients who died within 18 months of study enrollment died in hospital.

CONCLUSIONS

Providing home-based palliative care services for patients with advanced COPD is feasible but completing repeated questionnaires is impractical. Despite significant palliative supports, managing terminal symptoms exceeded caregivers' capacity to cope and forced hospital admission. Insights into systemic barriers and limitations of current palliative care service models can provide opportunities for local program innovation aimed at improving care for advanced COPD.

Adjudication of bleeding outcomes in an international thromboprophylaxis trial in critical illness

INTRODUCTION

Measuring bleeding in critical care trials is challenging. We determined the reliability of adjudicated bleeding assessments in a large thromboprophylaxis trial in the intensive care unit (ICU).

MATERIALS AND METHODS

PROphylaxis for ThromboEmbolism in Critical Care Trial (PROTECT) was an international randomized controlled trial that compared dalteparin to unfractionated heparin for the prevention of deep vein thrombosis in the ICU. Daily bleeding data were collected prospectively using a validated tool. Bleeds were adjudicated in duplicate by 2 of 4 members comprising a central adjudication committee. Bleeds were stratified by severity and study drug, then randomly assigned to adjudicator pairs. Adjudicators were blinded to treatment allocation, study centre and peer-assessments. We calculated agreement on bleeding severity and examined the effect of adjudication on overall trial results.

RESULTS

In PROTECT, 491 patients had bleeding events including 208 with major bleeding and 283 with minor bleeding only. Of 491 patients, 446 were adjudicated in duplicate: 182 with major, 250 with minor and 14 with no bleeding. After adjudication, 52 of 244 bleeds were downgraded to minor; whereas only 15 of 244 were upgraded to major. Overall agreement among adjudicators was excellent (crude agreement=86.3%; kappa=0.76). Hazard ratios for major or any bleeding with dalteparin or unfractionated heparin were similar when analyzed using non-adjudicated events.

CONCLUSIONS

Major bleeds were sometimes over-called by research coordinators in a large ICU thromboprohylaxis trial. Adjudicator agreement was excellent. Central adjudication allowed reliable bleeding assessment and enhanced the rigor and validity of this major safety outcome.

Rates and determinants of informed consent: a case study of an international thromboprophylaxis trial

BACKGROUND

Successful completion of randomized trials depends upon efficiently and ethically screening patients and obtaining informed consent. Awareness of modifiable barriers to obtaining consent may inform ongoing and future trials.

OBJECTIVE

The objective of this study is to describe and examine determinants of consent rates in an international heparin thromboprophylaxis trial (Prophylaxis for ThromboEmbolism in Critical Care Trial, clinicaltrials.gov NCT00182143).

DESIGN

Throughout the 4-year trial, research personnel approached eligible critically ill patients or their substitute decision makers for informed consent. Whether consent was obtained or declined was documented daily.

SETTING

The trial was conducted in 67 centers in 6 countries.

MEASUREMENTS AND MAIN RESULTS

A total of 3764 patients were randomized. The overall consent rate was 82.2% (range, 50%-100%) across participating centers. Consent was obtained from substitute decision makers and patients in 90.1% and 9.9% of cases, respectively. Five factors were independently associated with consent rates. Research coordinators with more experience achieved higher consent rates (odds ratio [OR], 3.43; 95% confidence interval, 2.42-4.86; P < .001 for those with >10 years of experience). Consent rates were higher in smaller intensive care units with less than 15 beds compared with intensive care units with 15 to 20 beds, 21 to 25 beds, and greater than 25 beds (all ORs, <0.5; P < .001) and were higher in centers with more than 1 full-time research staff (OR, 1.95; 95% confidence interval, 1.28-2.99; P < .001). Consent rates were lower in centers affiliated with the Canadian Critical Care Trials Group or the Australian and New Zealand Intensive Care Society Clinical Trials Group compared with other centers (OR, 0.57; 95% confidence interval, 0.42-0.77; P < .001). Finally, consent rates were highest during the pilot trial, lowest during the initiation of the full trial, and increased over years of recruitment (P < .001).

CONCLUSIONS

Characteristics of study centers, research infrastructure, and experience were important factors associated with successfully procuring informed consent to participate in this thromboprophylaxis trial.

Unfractionated heparin versus low molecular weight heparin for avoiding heparin-induced thrombocytopenia in postoperative patients

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction presenting as a prothrombotic disorder related to antibody-mediated platelet activation. It is a poorly understood paradoxical immune reaction resulting in thrombin generation in vivo, which leads to a hypercoagulable state and the potential to initiate venous or arterial thrombosis. A number of factors are thought to influence the incidence of HIT including the type and preparation of heparin (unfractionated heparin (UFH) or low molecular weight heparin (LMWH)) and the heparin-exposed patient population, with the postoperative patient population presenting a higher risk.Although LMWH has largely replaced UFH as a front-line therapy, there is evidence supporting a lack of superiority of LMWH compared with UFH regarding prevention of deep vein thrombosis and pulmonary embolism following surgery, and similar frequencies of bleeding have been described with LMWH and UFH. The decision as to which of these two preparations of heparin to use may thus be influenced by adverse reactions such as HIT. We therefore sought to determine the relative impact of UFH and LMWH specifically on HIT in postoperative patients receiving thromboembolism prophylaxis.

OBJECTIVES

The objective of this review was to compare the incidence of HIT and HIT complicated by thrombosis in patients exposed to UFH versus LMWH in randomised controlled trials (RCTs) of postoperative heparin therapy.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (March 2012) and CENTRAL (2012, Issue 2). In addition, the authors searched LILACS (March 2012) and additional trials were sought from reference lists of relevant publications.

SELECTION CRITERIA

We were interested in comparing the incidence of HIT occurring during exposure to UFH or LMWH after any surgical intervention. Therefore, we studied RCTs in which participants were postoperative patients allocated to receive UFH or LMWH, in a blinded or unblinded fashion. Eligible studies were required to have as an outcome clinically diagnosed HIT, defined as a relative reduction in the platelet count of 50% or greater from the postoperative peak (even if the platelet count at its lowest remained > 150 x 10(9)/L) occurring within five to 14 days after the surgery, with or without a thrombotic event occurring in this timeframe. Additionally, circulating antibodies associated with the syndrome were required to have been investigated through laboratory assays.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias. Disagreements were resolved by consensus with participation of a third author.

MAIN RESULTS

In total two studies involving 923 participants met all the inclusion criteria and were included in the review. Pooled analysis showed a statistically significant reduction in the risk of HIT with LMWH compared with UFH (risk ratio (RR) 0.24, 95% confidence interval (CI) 0.07 to 0.82; P = 0.02). This result suggests that patients treated with LMWH would have a relative risk reduction (RRR) of 76% in the probability of developing HIT compared with patients treated with UFH.Venous thromboembolism (VTE) complicating HIT occurred in 12 of 17 patients who developed HIT. Pooled analysis showed a statistically significant reduction in HIT complicated by VTE with LMWH compared with UFH (RR 0.20, 95% CI 0.04 to 0.90; P = 0.04). This result indicates that patients using LMWH would have a RRR of 80% for developing HIT complicated by VTE compared with patients using UFH. Arterial thrombosis occurred in only one patient who received UFH and there were no amputations or deaths documented.

AUTHORS' CONCLUSIONS

There was a lower incidence of HIT and HIT complicated by VTE in postoperative patients undergoing thromboprophylaxis with LMWH compared with UFH. This is consistent with the current clinical use of LMWH over UFH as front-line heparin therapy. However, conclusions are limited by a scarcity of high quality evidence. We did not expect the paucity of RCTs including HIT as an outcome as heparin is one of the most commonly used drugs worldwide and HIT is a life-threatening adverse drug reaction. To address the scarcity of clinically-relevant information on the topic of HIT as a whole, HIT should be included as an outcome in future RCTs of heparin, and HIT as an adverse drug reaction should be considered in clinical recommendations regarding monitoring of the platelet count for HIT.

A randomized controlled pilot study assessing the feasibility of combined motor-cognitive training and its effect on gait characteristics in the elderly

OBJECTIVE

(1) To develop a motor-cognition training programme; (2) to evaluate the ability to recruit and retain elderly people; (3) to assess the effects of the interventions.

DESIGN

Pilot randomized controlled trial.

SETTING

Assisted living facility.

PARTICIPANTS

Sixteen subjects (11 female) living in an assisted living facility were randomized to a motor or motor-cognition group.

INTERVENTIONS

Both groups received machine-driven strength training and balance exercises for 45 minutes, twice weekly, for 12 weeks. In addition, the motor-cognition group received computerized training for attention 3-5 times per week for 10 weeks.

MAIN OUTCOME MEASURES

Baseline and post-intervention (12 weeks) assessments focused on recruitment, attrition and adherence. Secondary outcome measures assessed dual-task costs of gait (velocity, cadence, step time, step length), expanded timed get-up-and-go, falls efficacy and reaction time.

RESULTS

Of 35 subjects initially approached, 16 started and 14 completed the study, resulting in 46% recruitment, 19% attrition and >80% adherence rates. There is more evidence of altered levels in the motor-cognitive treatment group with significant differences in average change for fear of falling (P = 0.017) and foot reaction time (P = 0.046). No statistical significance was reached for gait parameters.

CONCLUSIONS

Motor-cognition training is feasible and shows trends to stronger improvement in walking and reaction time. The application in a main study is deemed feasible. A minimum of ± 55 subjects per group are required to achieve a power of 80% at the 5% level of significance based on step length and considering the expectable attrition rate in a required larger scale study.

Current anticoagulant safety

INTRODUCTION

Currently used anticoagulants such as unfractionated heparin, low-molecular-weight heparin and vitamin K antagonists, have several drawbacks, mostly related to safety. In this review, we will briefly discuss and compare the safety of anticoagulation therapy with 'old' and new agents.

AREAS COVERED

Safety issues with anticoagulation therapy are mostly related to bleeding. The intensity of anticoagulation is related to the risk of bleeding and thus, for the efficacy not to be affected, must be maintained at the lower effective intensity. Several improvements have been made in the management of anticoagulation therapy; these include monitoring, pathology-based treatment schemes taking into account patient characteristics, patient education and the introduction of anticoagulation centers. Safety of novel anticoagulants is encouraging.

EXPERT OPINION

Novel agents have the potential to compete with existing therapy for thromboprophylaxis, treatment and stroke prevention in atrial fibrillation. Promising results have emerged from trials comparing them with existing treatment. Not long from now we will see these new agents in the armamentarium of antithrombotic drugs.

Recommendations for planning pilot studies in clinical and translational research

Advances in clinical and translation science are facilitated by building on prior knowledge gained through experimentation and observation. In the context of drug development, preclinical studies are followed by a progression of phase I through phase IV clinical trials. At each step, the study design and statistical strategies are framed around research questions that are prerequisites for the next phase. In other types of biomedical research, pilot studies are used for gathering preliminary support for the next research step. However, the phrase "pilot study" is liberally applied to projects with little or no funding, characteristic of studies with poorly developed research proposals, and usually conducted with no detailed thought of the subsequent study. In this article, we present a rigorous definition of a pilot study, offer recommendations for the design, analysis and sample size justification of pilot studies in clinical and translational research, and emphasize the important role that well-designed pilot studies play in the advancement of science and scientific careers.

Fluid Resuscitation with 5% albumin versus Normal Saline in Early Septic Shock: a pilot randomized, controlled trial

PURPOSE

Randomized, controlled trials of fluid resuscitation in early septic shock face many logistic challenges. We describe the Fluid Resuscitation with 5% albumin versus Normal Saline in Early Septic Shock (PRECISE) pilot trial study design and report feasibility of patient recruitment.

MATERIALS AND METHODS

Six Canadian academic centers enrolled adult patients with early suspected septic shock from the emergency department and intensive care unit department. Consent was deferred. Using concealed allocation, participants were randomized to either 5% albumin or 0.9% sodium chloride. Blinded fluid resuscitation started immediately and continued for 7 days in the intensive care unit. Target recruitment was established a priori at 2 patients per site per month.

RESULTS

Fifty-one patients were enrolled; 50 patients received study fluid. We recruited a median of 2.5 patients (interquartile range [IQR], 1.5-3.0) per site per month into the trial. Median age and Acute Physiology and Chronic Health Evaluation II scores were 64.5 (IQR, 55.0-78.0) and 25.0 (IQR, 20.0-29.0), respectively. Most patients (n = 37 [74.0%]) were enrolled from the emergency department for a median of 1.6 hours (IQR, 0.8-3.5 hours) from their first hypotensive event and received a median of 2.4 L (IQR, 1.5-3.0 L) of resuscitation fluid before inclusion. Consent was deferred for 44 patients (89.8%).

CONCLUSIONS

Patient recruitment into the PRECISE pilot trial met our prespecified feasibility targets, and the PRECISE team is planning the larger trial.

Does dalteparin PROTECT better than heparin?

Expanded abstract

PROphylaxis for ThromboEmbolism in Critical Care Trial protocol and analysis plan

BACKGROUND

This article reports the preparatory studies as well as the design, implementation, and a priori analysis plans of PROphylaxis for ThromboEmbolism in Critical Care Trial (PROTECT) before dissemination of results. PROphylaxis for ThromboEmbolism in Critical Care Trial (NCT00182143) is a randomized, stratified, concealed international trial comparing subcutaneous injection of unfractionated heparin (UFH) 5000 IU or the low-molecular weight heparin (LMWH) dalteparin 5000 IU once daily plus once-daily placebo for the duration of the intensive care unit stay.

METHODS

The objective of PROTECT is to examine, among medical-surgical critically ill patients, the effect of the LMWH vs heparin on the primary outcome of proximal leg deep vein thrombosis (DVT) and the following secondary outcomes: DVT elsewhere, pulmonary embolism, any venous thromboembolism (DVT or pulmonary embolism), the composite of venous thromboembolism or death, bleeding, and heparin-induced thrombocytopenia. Patients are followed up to death or hospital discharge. Venous thromboembolism events were included after intensive care unit discharge. All patients, families, clinicians, research personnel, and the trial biostatistician are blind to allocation.

RESULTS

We describe the pilot work, large trial methodology, implementation methods, and the analytic plan. Patient recruitment is complete, but 2 patients remain in the hospital. The rigorous design of PROTECT suggests that the risk of systematic error will be low. The sample size suggests that the risk of random error will be low. PROTECT will be the largest investigator-initiated peer-review funded thromboprophylaxis trial in critical care in the world.

CONCLUSIONS

If PROTECT shows that LMWH is more effective than UFH, this trial will change practice in that LMWH may be the anticoagulant thromboprophylaxis of choice for this population. If the results show that UFH is as effective or more effective than LMWH, intensivists in many parts of the world may continue to use UFH, whereas those currently using LMWH may reconsider and change to use UFH. Unfavorable consequences such as major bleeding, ease of use, and the costs of complications will also factor into such decisions.

Screening and prevention of venous thromboembolism in critically ill patients: a decision analysis and economic evaluation

RATIONALE

Venous thromboembolism is difficult to diagnose in critically ill patients and may increase morbidity and mortality.

OBJECTIVES

To evaluate the cost-effectiveness of strategies to reduce morbidity from venous thromboembolism in critically ill patients.

METHODS

A Markov decision analytic model to compare weekly compression ultrasound screening (screening) plus investigation for clinically suspected deep vein thrombosis (DVT) (case finding) versus case finding alone; and a hypothetical program to increase adherence to DVT prevention. Probabilities were derived from a systematic review of venous thromboembolism in medical-surgical intensive care unit patients. Costs (in 2010 $US) were obtained from hospitals in Canada, Australia, and the United States, and the medical literature. Analyses were conducted from a societal perspective over a lifetime horizon. Outcomes included costs, quality-adjusted life-years (QALY), and incremental cost-effectiveness ratios.

MEASUREMENTS AND MAIN RESULTS

In the base case, the rate of proximal DVT was 85 per 1,000 patients. Screening resulted in three fewer pulmonary emboli than case-finding alone but also two additional bleeding episodes, and cost $223,801 per QALY gained. In sensitivity analyses, screening cost less than $50,000 per QALY only if the probability of proximal DVT increased from a baseline of 8.5-16%. By comparison, increasing adherence to appropriate pharmacologic thromboprophylaxis by 10% resulted in 16 fewer DVTs, one fewer pulmonary emboli, and one additional heparin-induced thrombocytopenia and bleeding event, and cost $27,953 per QALY gained. Programs achieving increased adherence to best-practice venous thromboembolism prevention were cost-effective over a wide range of program costs and were robust in probabilistic sensitivity analyses.

CONCLUSIONS

Appropriate prophylaxis provides better value in terms of costs and health gains than routine screening for DVT. Resources should be targeted at optimizing thromboprophylaxis.

Questions asked and answered in pilot and feasibility randomized controlled trials

BACKGROUND

In the last decade several authors have reviewed the features of pilot and feasibility studies and advised on the issues that should be addressed within them. We extend this literature by examining published pilot/feasibility trials that incorporate random allocation, examining their stated objectives, results presented and conclusions drawn, and comparing drug and non-drug trials.

METHODS

A search of EMBASE and MEDLINE databases for 2000 to 2009 revealed 3652 papers that met our search criteria. A random sample of 50 was selected for detailed review.

RESULTS

Most of the papers focused on efficacy: those reporting drug trials additionally addressed safety/toxicity; while those reporting non-drug trials additionally addressed methodological issues. In only 56% (95% confidence intervals 41% to 70%) were methodological issues discussed in substantial depth, 18% (95% confidence interval 9% to 30%) discussed future trials and only 12% (95% confidence interval 5% to 24%) of authors were actually conducting one.

CONCLUSIONS

Despite recent advice on topics that can appropriately be described as pilot or feasibility studies the large majority of recently published papers where authors have described their trial as a pilot or addressing feasibility do not primarily address methodological issues preparatory to planning a subsequent study, and this is particularly so for papers reporting drug trials. Many journals remain willing to accept the pilot/feasibility designation for a trial, possibly as an indication of inconclusive results or lack of adequate sample size.

Dalteparin versus unfractionated heparin in critically ill patients

BACKGROUND

The effects of thromboprophylaxis with low-molecular-weight heparin, as compared with unfractionated heparin, on venous thromboembolism, bleeding, and other outcomes are uncertain in critically ill patients.

METHODS

In this multicenter trial, we tested the superiority of dalteparin over unfractionated heparin by randomly assigning 3764 patients to receive either subcutaneous dalteparin (at a dose of 5000 IU once daily) plus placebo once daily (for parallel-group twice-daily injections) or unfractionated heparin (at a dose of 5000 IU twice daily) while they were in the intensive care unit. The primary outcome, proximal leg deep-vein thrombosis, was diagnosed on compression ultrasonography performed within 2 days after admission, twice weekly, and as clinically indicated. Additional testing for venous thromboembolism was performed as clinically indicated. Data were analyzed according to the intention-to-treat principle.

RESULTS

There was no significant between-group difference in the rate of proximal leg deep-vein thrombosis, which occurred in 96 of 1873 patients (5.1%) receiving dalteparin versus 109 of 1873 patients (5.8%) receiving unfractionated heparin (hazard ratio in the dalteparin group, 0.92; 95% confidence interval [CI], 0.68 to 1.23; P=0.57). The proportion of patients with pulmonary emboli was significantly lower with dalteparin (24 patients, 1.3%) than with unfractionated heparin (43 patients, 2.3%) (hazard ratio, 0.51; 95% CI, 0.30 to 0.88; P=0.01). There was no significant between-group difference in the rates of major bleeding (hazard ratio, 1.00; 95% CI, 0.75 to 1.34; P=0.98) or death in the hospital (hazard ratio, 0.92; 95% CI, 0.80 to 1.05; P=0.21). In prespecified per-protocol analyses, the results were similar to those of the main analyses, but fewer patients receiving dalteparin had heparin-induced thrombocytopenia (hazard ratio, 0.27; 95% CI, 0.08 to 0.98; P=0.046).

CONCLUSIONS

Among critically ill patients, dalteparin was not superior to unfractionated heparin in decreasing the incidence of proximal deep-vein thrombosis. (Funded by the Canadian Institutes of Health Research and others; PROTECT ClinicalTrials.gov number, NCT00182143.).

Deep Vein Thrombosis and Stress Ulcer Prophylaxis in the Intensive Care Unit

Deep vein thrombosis (DVT) and stress gastric ulcers can be serious complications in patients admitted to the intensive care unit. This review discusses the risk factors associated with the development of DVT and stress-related mucosal disease (SRMD), evaluates the available literature on current options for DVT and stress ulcer prophylaxis, and examines the associated adverse effects and optimal duration of therapy.

Venous thromboembolic disease in trauma and surveillance ultrasonography

BACKGROUND

The literature reports a wide variation in the incidence of venous thromboembolic (VTE) disease in trauma patients. The performance of routine surveillance venous duplex ultrasound of bilateral lower extremities is controversial. Furthermore, recent examinations of the national trauma databank registry have suggested that routine duplex surveillance is associated with higher deep venous thrombosis (DVT) detection rates.

MATERIALS AND METHODS

We examined the incidence and risk factors for VTE disease in 2827 trauma patients admitted over a 2-y period to a state-verified level I trauma center. Detailed chart review was carried out for patients with VTE disease. We then evaluated the effects of a routine bilateral lower extremity duplex surveillance guideline on VTE detection in the subset of injury patients admitted to the trauma service.

RESULTS

We found an approximately 2% incidence of venous thromboembolic disease in a mostly blunt trauma population. Amongst patients with VTE disease, the most common risk factors were obesity and significant head injury. We then evaluated the 998 patients with injury who were admitted to the trauma service 1 y before and after surveillance guideline implementation. Despite a nearly 5-fold increase in the number of duplex scans, with a substantial increase in cost, we found no significant difference in the incidence of DVT.

CONCLUSIONS

Our preliminary data argue against the use of routine duplex surveillance of lower extremities for DVT in trauma patients. A larger, prospective analysis is necessary to confirm these findings.

Adverse drug events associated with disorders of coagulation

Disorders of coagulation are common adverse drug events encountered in critically ill patients and present a serious concern for intensive care unit (ICU) clinicians. Dosing strategies for medications used in the ICU are typically developed for use in noncritically ill patients and, therefore, do not account for the altered pharmacokinetic and pharmacodynamic properties encountered in the critically ill as well as the increased potential for drug-drug interactions, given the far greater number of medications ordered. This substantially increases the risk for coagulation-related adverse reactions, such as a bleeding or prothrombotic events. Although many medications used in the ICU have the potential to cause coagulation disorders, the exact incidence will vary based on the specific medication, dose, concomitant drug therapy, ICU setting, and patient-specific comorbidities. Clinicians must strongly consider these factors when evaluating the risk/benefit ratio for a particular therapy. This review surveys recent literature documenting the risk for adverse drug reactions specific to bleeding and/or clotting with commonly used medications in the ICU.

Dosing Low Molecular Weight Heparins in Kidney Disease

The low molecular weigh heparins (LMWHs) are primarily eliminated renally, and current literature indicates that there is a reduction in clearance and an increase in half-life of LMWHs in patients with severe chronic kidney disease (CKD) associated with elevated anti-Xa levels and an increased risk of bleeding. It therefore becomes clinically prudent to evaluate dosing adjustments in CKD. The American College of Chest Physicians (ACCP), in its 2008 consensus statement, recommends 5 possible approaches to dosing LMWH in patients with severe CKD. In evaluating the individual compounds, enoxaparin, dalteparin, and tinzaparin, this article attempts to address the preferred dosing strategies.

Thromboprophylaxis in the intensive care unit: focus on medical-surgical patients

Critically ill patients in the medical-surgical intensive care unit are at high risk for deep venous thrombosis and pulmonary embolism, which comprise venous thromboembolism. Herein, we describe the prevalence, incidence, risk factors, clinical consequences, prophylaxis against venous thromboembolism in critically ill patients, and compliance with thromboprophylaxis. We focus primarily on medical-surgical intensive care unit patients, who represent the largest subgroup of critically ill patients. Despite the large and growing number of critically ill patients in our aging society, their high risk for venous thromboembolism, and the morbidity and mortality associated with this complication of critical illness, relatively few rigorous studies are available. Large, well-designed, randomized trials of thromboprophylaxis, powered to detect differences in patient-important outcomes, are required to advance our understanding and care of these vulnerable patients. Furthermore, because thromboprophylaxis is a common error of omission in hospitalized patients, redoubled efforts are needed to ensure that it is used in practice.

The 4Ts scoring system for heparin-induced thrombocytopenia in medical-surgical intensive care unit patients

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is commonly considered but rarely confirmed in critically ill patients. The 4Ts score (Thrombocytopenia, Timing of thrombocytopenia, Thrombosis, and oTher reason) might identify individual patients at risk of having this disorder.

OBJECTIVE

The aim of the study was to evaluate the value of the 4Ts HIT score in comparison with the serotonin-release assay (SRA) in critically ill patients.

METHODS

This study describes the combined results of 3 prospective studies enrolling critically ill patients who were investigated for HIT if platelets fell to less than 50 x 10(9)/L or if platelet counts decreased to less than 50% of the value upon intensive care unit admission. We confirmed HIT by a positive platelet SRA. We assigned a 4Ts score blinded to SRA results to all 50 patients investigated for HIT; those with positive SRA results were scored in duplicate.

RESULTS

Of 528 patients, 50 (9.5%) were investigated for HIT; 39 (78%) of 50 (64%-88%) of these patients were scored as "low probability" by 4Ts score and none had a positive SRA. Of 49 patients who underwent SRA testing because of thrombocytopenia, only 2 (4.1%; 0.5-14.0) had a positive SRA (1 with a moderate 4Ts score and 1 with a high 4Ts score). Therefore, the overall incidence of HIT confirmed by SRA was 2 (0.4%) of 528 (0.04%-1.4%).

CONCLUSIONS

Significant thrombocytopenia during heparin administration occurred in 9.5% of critically ill patients, but HIT was confirmed in only 4.1% of those undergoing testing, for an overall incidence of 0.4%. A low 4Ts score occurred in 78% of patients investigated for HIT; none of these patients had a positive SRA. We conclude that HIT is uncommon in critically ill patients and that the 4Ts score is worthy of further evaluation in this patient population.

A tutorial on pilot studies: the what, why and how

Pilot studies for phase III trials - which are comparative randomized trials designed to provide preliminary evidence on the clinical efficacy of a drug or intervention - are routinely performed in many clinical areas. Also commonly know as "feasibility" or "vanguard" studies, they are designed to assess the safety of treatment or interventions; to assess recruitment potential; to assess the feasibility of international collaboration or coordination for multicentre trials; to increase clinical experience with the study medication or intervention for the phase III trials. They are the best way to assess feasibility of a large, expensive full-scale study, and in fact are an almost essential pre-requisite. Conducting a pilot prior to the main study can enhance the likelihood of success of the main study and potentially help to avoid doomed main studies. The objective of this paper is to provide a detailed examination of the key aspects of pilot studies for phase III trials including: 1) the general reasons for conducting a pilot study; 2) the relationships between pilot studies, proof-of-concept studies, and adaptive designs; 3) the challenges of and misconceptions about pilot studies; 4) the criteria for evaluating the success of a pilot study; 5) frequently asked questions about pilot studies; 7) some ethical aspects related to pilot studies; and 8) some suggestions on how to report the results of pilot investigations using the CONSORT format.

Reduction in deep vein thrombosis incidence in intensive care after a clinician education program

BACKGROUND

Deep vein thrombosis (DVT) is a major complication in intensive care units (ICU) but dedicated guidelines on its management are still lacking.

OBJECTIVES AND METHODS

This study investigated the effect of a 1-year educational program for the implementation of DVT prophylaxis on the incidence of inferior limb DVT in a mixed-bed ICU that admits high-risk surgical and trauma patients, investigated during a first retrospective phase [126 patients, SAPS II score 42 (28-54)] and a following prospective phase [264 patients, SAPS II score II 41 (27-55)]. The role of baseline and time-dependent DVT risk factors in DVT occurrence was also investigated during the prospective phase.

RESULTS

The educational program on implementation of DVT prophylaxis was associated with a significant decrease in DVT incidence from 11.9% to 4.5% (P < 0.01) and in the mean length of ICU stay (P < 0.01). Combined with pharmacological prophylaxis, the use of elastic compressive stockings significantly also increased in the prospective phase (P < 0.01). The duration of mechanical ventilation, vasopressor administration and neuromuscular block were significantly different between DVT-positive and DVT-negative patients (P < 0.01). Multivariate analysis identified neuromuscular block as the strongest independent predictor for DVT incidence.

CONCLUSION

One-year ICU-based educational programs on implementation of DVT prophylaxis were associated with a significant decrease in the incidence of DVT and also in the length of stay in ICU.

Low-molecular-weight heparin thromboprophylaxis in medical-surgical critically ill patients: a systematic review

PURPOSE

The study aimed to systematically review the effect of low-molecular-weight heparin (LMWH) thromboprophylaxis in medical-surgical critically ill patients in the intensive care unit.

METHODS

In duplicate and independently, we searched for relevant articles using MEDLINE and EMBASE; we also contacted experts and reviewed reference lists. For included studies, we abstracted data on study and patient characteristics, LMWH use, clinical outcomes (venous thromboembolism [VTE], bleeding, and mortality), laboratory outcomes (anti-Xa levels and thrombocytopenia), and methodological quality.

RESULTS

We included 8 prospective cohort studies and 1 randomized trial, with a total of 629 patients. Eight studies (n = 406 patients) reported anti-Xa levels and only 3 studies (n = 240 patients) reported on at least one clinical outcome. Low-molecular-weight heparin does not appear to bioaccumulate based on repeated measurements of trough anti-Xa levels. Thrombocytopenia occurred in 9.3% of patients receiving LMWH; heparin-induced thrombocytopenia was not reported. In studies reporting clinical outcomes, the frequency of VTE in patients receiving LMWH ranged from 5.1% to 15.5%, bleeding complications ranged from 7.2% to 23.1%, and mortality ranged from 1.4% to 7.4%.

CONCLUSIONS

Low-molecular-weight heparin may be effective for thromboprophylaxis in medical-surgical critically ill patients, but no trials have compared LMWH against an alternative active strategy; thus, LMWH cannot be recommended routinely. Trials testing LMWH thromboprophylaxis are required, which examine patient-important end points such as the incidence and clinical consequences of VTE, bleeding, heparin-induced thrombocytopenia, and mortality.

The design and interpretation of pilot trials in clinical research in critical care

BACKGROUND

Pilot trials are important to ensure that large randomized trials are rigorous, feasible, and economically justifiable. The objective of this review is to highlight the importance of randomized pilot trials and to describe key features of their design and interpretation using examples from critical care.

METHODS

We searched MEDLINE (1997-2007) and contacted experts to identify pilot randomized trials to exemplify and summarize their key methodologic features including objectives, sample size determination, outcomes, analysis, and reporting.

RESULTS

Pilot trials can have distinct and broad objectives. Investigators can predefine explicit criteria for determining their success. Surrogate outcome analyses are common in pilot trials, yet are usually underpowered to detect meaningful differences in clinically important end points and thus, should be cautiously interpreted. Pilot trials can facilitate successful conduct of large clinical trials by informing study design and streamlining protocol implementation.

RECOMMENDATIONS

We recommend that investigators define suitable objectives, determine sample size estimates, and select outcomes that will address their specific pilot trial objectives. Clinical effects documented in pilot trials should be reported with caution to avoid undue enthusiasm or pessimism about unstable estimates. Further methodologic work is required to identify optimal pilot trial design, indexing, and reporting.

Thromboprophylaxis in medical-surgical critically ill patients

PURPOSE OF REVIEW

Although critically ill patients are at high risk of venous thromboembolism and bleeding, and thromboprophlyaxis is of proven effectivity in other settings, there remain relatively few data to assist clinicians in providing evidence-based care for medical-surgical patients in the intensive care unit.

RECENT FINDINGS

Deep vein thrombosis occurs in 5-10% of critically ill patients even if they receive unfractionated heparin for prophylaxis. Both heparin and low molecular weight heparin can be safely administered to the majority of critically ill patients and the low molecular weight heparin dalteparin does not appear to bioaccumulate even when administered to patients with severe renal dysfunction. Further research is currently underway to better define how these conditions can be optimally treated.

SUMMARY

Despite the high morbidity and mortality because of critical illness, the risk of venous thromboembolism in these patients, and adverse outcomes due to venous thromboembolism, much more methodologically rigorous data are required in the form of large, well designed randomized trials before firm recommendations about prophylaxis can be provided to this highly vulnerable population.