Objects drawn from haptic perception and vision-based spatial abilities

Haptic perception is used in the anatomy laboratory with the handling of three-dimensional (3D) prosections, dissections, and synthetic models of anatomical structures. Vision-based spatial ability has been found to correlate with performance on tests of 3D anatomy knowledge in previous studies. The objective was to explore whether haptic-based spatial ability was correlated with vision-based spatial ability. Vision-based spatial ability was measured in a study group of 49 medical graduates with three separate tests: a redrawn Vandenberg and Kuse Mental Rotations Tests in two (MRT A) and three (MRT C) dimensions and a Surface Development Test (SDT). Haptic-based spatial ability was measured using 18 different objects constructed from 10 cubes glued together. Participants were asked to draw these objects from blind haptic perception, and drawings were scored by two independent judges. The maximum score was 24 for each of MRT A and MRT C, 60 for SDT, and 18 for the drawings. The drawing score based on haptic perception [median = 17 (lower quartile = 16, upper quartile = 18)] correlated with MRT A [14 (9, 17)], MRT C [9 (7, 12)] and SDT [44 (36, 52)] scores with a Spearman's rank correlation coefficient of 0.395 (p = 0.0049), 0.507 (p = 0.0002) and 0.606 (p < 0.0001), respectively. Spatial abilities assessed by vision-based tests were correlated with a drawing score based on haptic perception of objects. Future research should investigate the contribution of haptic-based and vision-based spatial abilities on learning 3D anatomy from physical models.

Mortality Risk Increases With Clustered Ventricular Arrhythmias in Patients With Implantable Cardioverter-Defibrillators

OBJECTIVES

This study sought to examine the adverse prognosis associated with ventricular arrhythmia clusters that falls outside the current electrical storm definition.

BACKGROUND

Electrical storm is most frequently defined as a cluster of ≥3 episodes of ventricular arrhythmia (VA) in a 24-h period. This definition has been associated with adverse cardiovascular outcomes and mortality, but the effect of lesser and greater clustering of arrhythmias has not been described.

METHODS

Among all patients in the Resynchronization in Ambulatory Heart Failure trial, 14,515 implantable cardioverter-defibrillator-detected events with data available were rigorously adjudicated in blinded fashion. Arrhythmia incidence was examined for clustering, defined as 2 or more VA events occurring within 3 months. The prognostic importance of clustering was analyzed by varying the cluster length and number of events used to define a cluster. Mortality rates of groups with clustered arrhythmias were compared to patients with no arrhythmia or with unclustered arrhythmia.

RESULTS

The trial included 1,764 patients, among whom 465 patients had two or more VA episodes within 3 months, whereas 406 had unclustered arrhythmias. Compared to patients with no arrhythmia, patients experiencing unclustered VA had increased risk of death (hazard ratio [HR]: 1.45; 95% confidence interval [CI]: 1.09 to 1.93; p = 0.011), whereas the risk was even higher in patients with clustered arrhythmia (HR: 2.68; 95% CI: 2.13 to 3.36; p < 0.0001). Mortality risk increased with higher VA burden (number of VAs in a cluster) and shorter cluster length. This was observed in all groups tested, including the cluster with the least VA burden in the longest cluster length tested (2 VA episodes occurring within 3 months) (mortality HR: 2.85; 95% CI: 1.95 to 4.17; p < 0.0001). Although clustered arrhythmias terminated with antitachycardia pacing were associated with increased mortality, clusters terminated with implantable cardioverter-defibrillator shocks were associated with still higher mortality risk.

CONCLUSIONS

Significant adverse prognostic association of clustered VAs is observable with even 2 VA events within 3 months and increases with higher cluster density.

Pertuzumab, trastuzumab and taxane-based treatment for visceral organ metastatic, trastuzumab-naïve breast cancer: real-life practice outcomes

PURPOSE

In this study, we aimed to describe the real-life practice outcomes of pertuzumab-trastuzumab-taxane (PTT) combination in visceral organ metastatic, trastuzumab-naive breast cancer (BC) patients.

METHODS

This study was conducted by Turkish Oncology Group and included 317 patients' data from 36 centers.

RESULTS

Median age was 51 (22-82). Median PFS was 28.5 months, while median OS was 40.3 months. Patients with brain metastases (n: 13, 4.1%) had worse PFS (16.8 m vs. 28.5 m; p = 0.002) and OS (26.7 m vs. 40.3 m; p = 0.009). Patients older than 65 years of age (n: 42, 13.2%) had significantly lower OS results (19.8 m vs. 40.3 m; p = 0.01). Two hundred sixty-eight patients (86.7%) received docetaxel while 37 patients (11.7%) received paclitaxel. PFS and OS were similar between taxane groups. In eight patients (2.5%), 5-40% ejection fraction decrement from baseline was detected without any clinical sign of heart failure.

CONCLUSIONS

Our RLP trial included only visceral metastatic, trastuzumab-naïve BC patients including cases with brain involvement who received PTT combination in the first-line treatment. Regardless of negative prognostic characteristics, our results are in parallel with pivotal trial. Further strategies for brain metastasis should be developed to improve outcomes despite encouraging results with PTT treatment. Taxane selection can be personalized and endocrine maintenance may further improve outcomes after taxanes were discontinued. To our knowledge, this is the largest scale real-life clinical practice study of pertuzumab-trastuzumab-taxane therapy to date.

Cardiac Resynchronization Therapy Reduces Ventricular Arrhythmias in Primary but Not Secondary Prophylactic Implantable Cardioverter Defibrillator Patients

Background—

The RAFT (Resynchronization in Ambulatory Heart Failure Trial) demonstrated that cardiac resynchronization therapy (CRT) reduced both mortality and heart failure hospitalizations in patients with functional class II or III heart failure and widened QRS. We examined the influence of CRT on ventricular arrhythmias in patients with primary versus secondary prophylaxis defibrillator indications.

Methods and Results—

All ventricular arrhythmias among RAFT study participants were downloaded and adjudicated by 2 blinded reviewers with an overreader for disagreements and committee review for remaining discrepancies. Incidence of ventricular arrhythmias among patients randomized to CRT-D versus implantable cardioverter defibrillator (ICD) were compared within the groups of patients treated for primary prophylaxis and for secondary prophylaxis. Of 1798 enrolled patients, 1764 had data available for adjudication and were included. Of these, 1531 patients were implanted for primary prophylaxis, while 233 patients were implanted for secondary prophylaxis; 884 patients were randomized to ICD and 880 to CRT-D. During 5953.6 patient-years of follow-up, there were 11 278 appropriate ICD detections of ventricular arrhythmias. In the primary prophylaxis group, CRT-D significantly reduced incidence ventricular arrhythmias in comparison to ICD (hazard ratio, 0.86; 95% confidence interval, 0.74–0.99; P =0.044). This effect was not seen in the secondary prophylaxis group (hazard ratio, 1.14; 95% confidence interval, 0.82–1.58; P =0.45). CRT-D was not associated with significant differences in overall ventricular arrhythmia burden in either group.

Conclusions—

CRT reduced the rate of onset of new ventricular arrhythmias detected by ICDs in patients without a history of prior ventricular arrhythmias. This effect was not observed among patients who had prior ventricular arrhythmias.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00251251.

Spatial abilities of medical graduates and choice of residency programs

Spatial abilities have been related in previous studies to three-dimensional (3D) anatomy knowledge and the performance in technical skills. The objective of this study was to relate spatial abilities to residency programs with different levels of content of 3D anatomy knowledge and technical skills. The hypothesis was that the choice of residency program is related to spatial abilities. A cohort of 210 medical graduates was enrolled in a prospective study in a 5-year experiment. Spatial abilities were measured with a redrawn Vandenberg and Kuse Mental Rotations Test (MRT) in two (MRTA) and three (MRTC) dimensions. Medical graduates were enrolled in Family Medicine (n = 76, 36.2%), Internal Medicine (64, 30.5%), Surgery (52, 24.8%), and Anesthesia (18, 8.6%). The assumption was that the level of 3D anatomy knowledge and technical skills content was higher in Surgery and Anesthesia compared to Family Medicine and Internal Medicine. Mean MRTA score of 12.4 (±SD 4.6), 12.0 (±4.3), 14.1 (±4.3), and 14.6 (±4.0) was obtained in Family Medicine, Internal Medicine, Surgery, and Anesthesia, respectively (P = 0.0176). Similarly, mean MRTC score of 8.0 (±4.4), 7.5 (±3.6), 8.5 (±3.9), and 7.9 (±4.1) was obtained (P = 0.5647). Although there was a tendency for lower MRTA score in Family Medicine and Internal Medicine compared to Surgery and Anesthesia, no statistically significant main effect of residency, year, sex, or the interactions were observed for the MRTA and MRTC. Studied sample of medical graduates was not found to choose their residency programs based on their innate spatial abilities.

Incidence, predictors, and procedural results of upgrade to resynchronization therapy: the RAFT upgrade substudy

BACKGROUND

The resynchronization-defibrillation for ambulatory heart failure trial (RAFT) study demonstrated that adding cardiac resynchronization therapy (CRT) in selected patients requiring de novo implantable cardiac defibrillators (ICD) reduced mortality as compared with ICD therapy alone, despite an increase in procedure-related adverse events. Data are lacking regarding the management of patients with ICD therapy who develop an indication for CRT upgrade.

METHODS AND RESULTS

Participating RAFT centers provided data regarding de novo CRT-D (CRT with ICD) implant, upgrade to CRT-D during RAFT (study upgrade), and upgrade within 6 months after presentation of study results (substudy). Substudy centers enrolled 1346 (74.9%) patients in RAFT, including 644 de novo, 80 study upgrade, and 60 substudy CRT attempts. The success rate (initial plus repeat attempts) was 95.2% for de novo versus 96.3% for study upgrade and 90.0% for substudy CRT attempts (P=0.402). Acute complications occurred among 26.2% of de novo versus 18.8% of study upgrade and 3.4% of substudy CRT implantation attempts (P<0.001). The most common complication was left ventricular lead dislodgement. The principal reasons for not yet attempting upgrade in the substudy were patient preference (31.9%), New York Heart Association Class I (17.0%), and a QRS<150 ms (13.1%).

CONCLUSIONS

Among a broad group of implant physicians, CRT upgrades were performed in patients with an ICD in situ with no difference in implant success rate and a reduced acute complication rate as compared with a de novo CRT implant. Decisions to upgrade were influenced by predictors of benefit in subgroup analyses of the RAFT study and other trials.

Sex differences in spatial abilities of medical graduates entering residency programs

Sex differences favoring males in spatial abilities have been known by cognitive psychologists for more than half a century. Spatial abilities have been related to three-dimensional anatomy knowledge and the performance in technical skills. The issue of sex differences in spatial abilities has not been addressed formally in the medical field. The objective of this study was to test an a priori hypothesis of sex differences in spatial abilities in a group of medical graduates entering their residency programs over a five-year period. A cohort of 214 medical graduates entering their specialist residency training programs was enrolled in a prospective study. Spatial abilities were measured with a redrawn Vandenberg and Kuse Mental Rotations Tests in two (MRTA) and three (MRTC) dimensions. Sex differences favoring males were identified in 131 (61.2%) female and 83 (38.8%) male medical graduates with the median (Q1, Q3) MRTA score [12 (8, 14) vs. 15 (12, 18), respectively; P < 0.0001] and MRTC score [7 (5, 9) vs. 9 (7, 12), respectively; P < 0.0001]. Sex differences in spatial abilities favoring males were demonstrated in the field of medical education, in a group of medical graduates entering their residency programs in a five-year experiment. Caution should be exerted in applying our group finding to individuals because a particular female may have higher spatial abilities and a particular male may have lower spatial abilities.

Cardiac resynchronization therapy: a meta-analysis of randomized controlled trials

BACKGROUND

Studies of cardiac resynchronization therapy in addition to an implantable cardioverter defibrillator in patients with mild to moderate congestive heart failure had not been shown to reduce mortality until the recent RAFT trial (Resynchronization/Defibrillation for Ambulatory Heart Failure Trial). We performed a meta-analysis including the RAFT trial to determine the effect of cardiac resynchronization therapy with or without an implantable defibrillator on mortality.

METHODS

We searched electronic databases and other sources for reports of randomized trials using a parallel or crossover design. We included studies involving patients with heart failure receiving optimal medical therapy that compared cardiac resynchronization therapy with optimal medical therapy alone, or cardiac resynchronization therapy plus an implantable defibrillator with a standard implantable defibrillator. The primary outcome was mortality. The optimum information size was considered to assess the minimum amount of information required in the literature to reach reliable conclusions about cardiac resynchronization therapy.

RESULTS

Of 3071 reports identified, 12 studies (n = 7538) were included in our meta-analysis. Compared with optimal medical therapy alone, cardiac resynchronization therapy plus optimal medical therapy significantly reduced mortality (relative risk [RR] 0.73, 95% confidence interval [CI] 0.62-0.85). Compared with an implantable defibrillator alone, cardiac resynchronization therapy plus an implantable defibrillator significantly reduced mortality (RR 0.83, 95% CI 0.72-0.96). This last finding remained significant among patients with New York Heart Association (NYHA) class I or II disease (RR 0.80, 95% CI 0.67-0.96) but not among those with class III or IV disease (RR 0.84, 95% CI 0.69-1.07). Analysis of the optimum information size showed that the sequential monitoring boundary was crossed, which suggests no need for further clinical trials.

INTERPRETATION

The cumulative evidence is now conclusive that the addition of cardiac resynchronization to optimal medical therapy or defibrillator therapy significantly reduces mortality among patients with heart failure.

Spatial abilities in an elective course of applied anatomy after a problem-based learning curriculum

A concern on the level of anatomy knowledge reached after a problem-based learning curriculum has been documented in the literature. Spatial anatomy, arguably the highest level in anatomy knowledge, has been related to spatial abilities. Our first objective was to test the hypothesis that residents are interested in a course of applied anatomy after a problem-based learning curriculum. Our second objective was to test the hypothesis that the interest of residents is driven by innate higher spatial abilities. Fifty-nine residents were invited to take an elective applied anatomy course in a prospective study. Spatial abilities were measured with a redrawn Vandenberg and Kuse Mental Rotations Test in two (MRT A) and three (MRT C) dimensions. A need for a greater knowledge in anatomy was expressed by 25 residents after a problem-based learning curriculum. MRT A and C scores obtained by those choosing (n = 25) and not choosing (n = 34) applied anatomy was not different (P = 0.46 and P = 0.38, respectively). Percentage of residents in each residency program choosing applied anatomy was different [23 vs. 31 vs. 100 vs. 100% in Family Medicine, Internal Medicine, Surgery, and Anesthesia, respectively; P < 0.0001]. The interest of residents in applied anatomy was not driven by innate higher spatial abilities. Our applied anatomy course was chosen by many residents because of training needs rather than innate spatial abilities. Future research will need to assess the relationship of individual differences in spatial abilities to learning spatial anatomy.

Ibandronate for the prevention of nonvertebral fractures: a pooled analysis of individual patient data

This analysis was conducted to assess the effect of high versus lower doses of ibandronate on nonvertebral fractures. The results were adjusted for clinical fracture, age, and bone density. The treatment effect was dose-dependent. Higher doses of ibandronate significantly reduced the risk of nonvertebral fractures more effectively compared with lower doses.

INTRODUCTION

The objective of this study was to assess the efficacy of different doses of ibandronate on nonvertebral fractures in a pooled analysis.

METHODS

Eight randomized trials of ibandronate were reviewed for inclusion. Alternative definitions of high versus low doses based on annual cumulative exposure (ACE) were explored. A time-to-event analysis was conducted using Kaplan-Meier methodology. Hazard ratios (HR) were derived using Cox regression and adjusted for covariates.

RESULTS

Combining higher ACE doses of > or = 10.8 mg (150 mg once monthly, 3 mg i.v. quarterly, and 2 mg i.v. every 2 months) versus ACE doses of 5.5 mg, from two trials, resulted in an HR 0.62 (95% CI 0.396-0.974, p = 0.038). There was a dose-response trend with increasing ACE doses (7.2-12 mg) versus ACE of 5.5 mg.

CONCLUSIONS

A dose-response effect on nonvertebral fractures was observed when comparing high with low ACE doses. A significant reduction in nonvertebral fractures was noted when pooling data from trials using ACE doses of > or = 10.8 mg versus ACE < or = 7.2 mg; and with ACE > or = 10.8 mg versus ACE of 5.5 mg (38% reduction). Higher ibandronate dose levels (150 mg monthly or 3 mg i.v. quarterly) significantly reduced nonvertebral fracture risk in postmenopausal women.

Sequential response-adapted induction and consolidation regimens idarubicin/cytarabine and mitoxantrone/etoposide in adult acute myelogenous leukemia: 10 year follow-up of a study by the Canadian Leukemia Studies Group

PURPOSE

The Canadian Leukemia Studies Group (CLSG) sought to test the safety and efficacy of response-adapted, non-cross resistant chemotherapy in de novo acute myeloid leukemia (AML). The combinations of idarubicin 12 mg/m(2)/d on days 1 - 3 and Ara-C (200 mg/m(2)/d) on days 1 - 7 (IDAC) followed by mitoxantrone 10 mg/m(2)/day, and etoposide 100 mg/m(2)/day, on days 1 - 5 (NOVE) were used according to patient response to induction and consolidation.

PATIENTS AND METHODS

In this multi-centre open-label phase II study, 140 patients up to age 80 were given induction with IDAC. Patients were entered between March 1993 and August 1995. If patients had persistent blasts at day 14 or on recovery, they were given NOVE. As consolidation, patients achieving complete remission (CR) with IDAC were given 1 further cycle of IDAC and 1 cycle of NOVE. Patients achieving CR after NOVE were given 2 further cycles of NOVE.

RESULTS

76% of all patients achieved remission after IDAC +/- NOVE, 81% in patients aged < or =60 years and 67% in patients aged >60. Overall, induction mortality was 11% and toxicity was similar to other cooperative group studies. Median follow-up was 104.0 months with 95% CI: (100.0, 105.2). Median overall survival (OS) in responding patients < or =60 was not reached: of the 79 responders < or =60, 35 died. The median disease free survival (DFS) in these responding patients was 22.7 (14.9, na) months. Median OS and DFS in responding patients >60 was 10.0 (7.3, 15.2) months and 7.5 (6.2, 15.2) months, respectively.

CONCLUSION

The results of this trial are very encouraging and suggest that there may be long-term benefit to this method. On the basis of these results, a randomized phase III trial has been performed.

Effect of a liberal versus restrictive transfusion strategy on mortality in patients with moderate to severe head injury

OBJECTIVE

To compare a restrictive versus a liberal transfusion strategy in patients with moderate to severe closed head injury following multiple trauma in 13 Canadian intensive care units (ICUs).

METHODS

This is a subgroup analysis of a multicenter randomized controlled clinical trial involving sixty-seven critically ill patients from the Transfusion Requirements in the Critical Care trial who sustained a closed head injury. Patients had a hemoglobin concentration less than 9.0 g/dL within 72 hours of admission to the ICU. Patients were randomized to a restrictive allogeneic red blood cell transfusion strategy (hemoglobin 7.0 g/dL and maintained between 7.0 and 9.0 g/dL) or a liberal strategy (hemoglobin 10.0 g/dL and maintained between 10.0 and 12.0 g/dL).

RESULTS

Baseline characteristics in the restrictive ( n = 29) and the liberal ( n = 38) transfusion groups were comparable. Average hemoglobin concentrations and red blood cell units transfused per patient were significantly lower in the restrictive compared to the liberal group. The 30-day all-cause mortality rates in the restrictive group were 17% as compared to 13% in the liberal group (risk difference 4.1 with 95% confidence interval [CI], 13.4 to 21.5, p = 0.64). Presence of multiple organ dysfunction (12.1 +/- 6.4 versus 10.6 +/- 6.3, p = 0.35) and changes in multiple organ dysfunction from baseline scores adjusted for death (4.5 +/- 6.2 versus 3.4 +/- 6.2, p = 0.49) were similar between the restrictive and liberal transfusion groups, respectively. Median length of stay in ICU (10 days, interquartile range 5 to 21 days versus 8 days, interquartile range 5 to 11 days, p = 0.26) and hospital (27 days, interquartile range 14 to 39 days versus 30.5 days, interquartile range 17 to 47 days, p = 0.72) were similar between the restrictive and liberal transfusion groups.

CONCLUSIONS

We were unable to detect significant improvements in mortality with a liberal as compared to restrictive transfusion strategy in critically ill trauma victims with moderate to severe head injury.

Shelter-based managed alcohol administration to chronically homeless people addicted to alcohol

BACKGROUND

People who are homeless and chronically alcoholic have increased health problems, use of emergency services and police contact, with a low likelihood of rehabilitation. Harm reduction is a policy to decrease the adverse consequences of substance use without requiring abstinence. The shelter-based Managed Alcohol Project (MAP) was created to deliver health care to homeless adults with alcoholism and to minimize harm; its effect upon consumption of alcohol and use of crisis services is described as proof of principle.

METHODS

Subjects enrolled in MAP were dispensed alcohol on an hourly basis. Hospital charts were reviewed for all emergency department (ED) visits and admissions during the 3 years before and up to 2 years after program enrollment, and the police database was accessed for all encounters during the same periods. The results of blood tests were analyzed for trends. A questionnaire was administered to MAP participants and staff about alcohol use, health and activities of daily living before and during the program. Direct program costs were also recorded.

RESULTS

Seventeen adults with an average age of 51 years and a mean duration of alcoholism of 35 years were enrolled in MAP for an average of 16 months. Their monthly mean group total of ED visits decreased from 13.5 to 8 (p = 0.004); police encounters, from 18.1 to 8.8 (p = 0.018). Changes in blood test findings were nonsignificant. All program participants reported less alcohol consumption during MAP, and subjects and staff alike reported improved hygiene, compliance with medical care and health.

INTERPRETATION

A managed alcohol program for homeless people with chronic alcoholism can stabilize alcohol intake and significantly decrease ED visits and police encounters.

Prostaglandin E2vaginal gel to treat dystocia in spontaneous labour: a multicentre randomised placebo-controlled trial

OBJECTIVE

To test the safety and efficacy of prostaglandin E(2) (PgE(2)) as a treatment for dystocia in spontaneous labour.

DESIGN

Randomised, double-blind, placebo-controlled trial.

SETTING

Multicentre study in nine university-affiliated hospitals in Canada. Population Three hundred and thiry-two nulliparous women with spontaneous labour at term.

METHODS

Women who had progressed < 2 cm of cervical dilation in the 4 hours following the diagnosis of labour were randomly assigned to receive a single dose of either 1 mg (n= 112) or 2 mg (n= 111) PgE(2) vaginal gel or placebo gel (n= 109).

MAIN OUTCOME MEASURES

The primary outcome was resolution of dystocia, defined as a change in cervical dilatation of >0.5 cm per hour in the 6 hours following gel administration. Secondary outcomes were progress of labour, uterine hyperstimulation (more than five contractions in 10 minutes or a contraction lasting more than 2 minutes), use of oxytocin, method of delivery, maternal and neonatal morbidity.

RESULTS

Dystocia resolved more often after PgE(2) 1 mg (49%), RR 1.53 (95% CI 1.1, 2.1) and PgE(2) 2 mg (49%), RR 1.5 (CI 1.1, 2.1), compared with placebo (32%). Hyperstimulation was increased after PgE(2) 2 mg treatment (15%), RR 5.6 (95% CI 1.7, 18), but not after PgE(2) 1 mg (5.4%), RR 1.9 (CI 0.50, 7.6) when compared with placebo (2.8%). There was an increase in caesarean sections performed in the second stage of labour in the PgE(2) groups versus placebo. There were no differences in measures of maternal or neonatal morbidity.

CONCLUSION

A single 1-mg dose of PgE(2) vaginal gel is more effective than placebo in resolving dystocia, without increasing uterine hyperstimulation, but may be associated with an increase in the incidence of second stage caesarean section.

Is a Restrictive Transfusion Strategy Safe for Resuscitated and Critically Ill Trauma Patients?

BACKGROUND

An analysis from the prospective multicenter randomized controlled trial (Transfusion Requirements in Critical Care Trial) compared the use of restrictive and liberal transfusion strategies with resuscitated critically ill trauma patients.

METHODS

Critically ill trauma patients with a hemoglobin concentration less than 90 g/L within 72 hours of admission to the intensive care unit were randomized to a restrictive (hemoglobin concentration, 70 g/L) or liberal (hemoglobin concentration, 100 g/L) red blood cell transfusion strategy.

RESULTS

The baseline characteristics in the restrictive (n = 100) and liberal (n = 103) transfusion groups were comparable. The average hemoglobin concentrations (82.7 +/- 6.2 g/L vs. 104.3 +/- 12.2 g/L; p < 0.0001) and the red blood cell units transfused per patient (2.3 +/- 4.4 vs. 5.4 +/- 4.3; p < 0.0001) were significantly lower in the restrictive group than in the liberal group. The 30-day all-cause mortality rates in the restrictive group were 10%, as compared with 9% in the liberal group (p = 0.81). The presence of multiple organ dysfunction (9.2 +/- 6.3 vs. 9.0 +/- 6.0; p = 0.81), the changes in multiple organ dysfunction from baseline scores adjusted for death (1.2 +/- 6.1 vs. 1.9 +/- 5.7; p = 0.44), and the length of stay in the intensive care unit (9.8 +/- 8.1 vs. 10.2 +/- 8.7 days; p = 0.73) and hospital (31.4 +/- 17.1 vs. 33.7 +/- 17.7 days; p = 0.34) also were similar between the restrictive and liberal transfusion groups.

CONCLUSIONS

A restrictive red blood cell transfusion strategy appears to be safe for critically ill multiple-trauma patients. A randomized controlled trial would provide the appropriate level of evidence with regard to the daily use of blood in this population of patients.

Outpatient oral prednisone after emergency treatment of chronic obstructive pulmonary disease

BACKGROUND

In this randomized, double-blind, placebo-controlled trial, we studied the effectiveness of prednisone in reducing the risk of relapse after outpatient exacerbations of chronic obstructive pulmonary disease (COPD).

METHODS

We enrolled 147 patients who were being discharged from the emergency department after an exacerbation of COPD and randomly assigned them to 10 days of treatment with 40 mg of oral prednisone once daily or identical-appearing placebo. All patients received oral antibiotics for 10 days, plus inhaled bronchodilators. The primary end point was relapse, defined as an unscheduled visit to a physician's office or a return to the emergency department because of worsening dyspnea, within 30 days after randomization.

RESULTS

The overall rate of relapse at 30 days was lower in the prednisone group than in the placebo group (27 percent vs. 43 percent, P=0.05), and the time to relapse was prolonged in those taking prednisone (P=0.04). After 10 days of therapy, patients in the prednisone group had greater improvements in forced expiratory volume in one second than did patients in the placebo group (mean [+/-SD] increase from base line, 34+/-42 percent vs. 15+/-31 percent; P=0.007). Patients in the prednisone group also had significant improvements in dyspnea, as measured by the transitional dyspnea index (P=0.04) and by the dyspnea domain of the Chronic Respiratory Disease Index Questionnaire (P=0.02), but not in health-related quality of life (P=0.14).

CONCLUSIONS

Outpatient treatment with oral prednisone offers a small advantage over placebo in treating patients who are discharged from the emergency department with an exacerbation of COPD.

Do blood transfusions improve outcomes related to mechanical ventilation?

BACKGROUND

Correcting the decrease in oxygen delivery from anemia using allogeneic RBC transfusions has been hypothesized to help with increased oxygen demands during weaning from mechanical ventilation. However, it is also possible that transfusions hinder the process because RBCs may not be able to adequately increase oxygen delivery. In this study, we determined whether a liberal RBC transfusion strategy improved outcomes related to mechanical ventilation.

METHODS

Seven hundred thirteen patients receiving mechanical ventilation, representing a subgroup of patients from a larger trial, were randomized to either a restrictive transfusion strategy, receiving allogeneic RBC transfusions at a hemoglobin concentration of 7.0 g/dL (and maintained between 7.0 g/dL and to 9.0 g/dL), or to a liberal transfusion strategy, receiving RBCs at 10.0 g/dL (and maintained between 10.0 g/dL and 12.0 g/dL). The larger trial was designed to evaluate transfusion practice rather than weaning per se.

RESULTS

Baseline characteristics in the restrictive-strategy group (n = 357) and the liberal-strategy group (n = 356) were comparable. The average durations of mechanical ventilation were 8.3 +/- 8.1 days and 8.3 +/- 8.1 days (95% confidence interval [CI] around difference, - 0.79 to 1.68; p = 0.48), while ventilator-free days were 17.5 +/- 10.9 days and 16.1 +/- 11.4 days (95% CI around difference, - 3.07 to 0.21; p = 0.09) in the restrictive-strategy group vs the liberal-strategy group, respectively. Eighty-two percent of the patients in the restrictive-strategy group were considered successfully weaned and extubated for at least 24 h, compared to 78% for the liberal-strategy group (p = 0.19). The relative risk (RR) of extubation success in the restrictive-strategy group compared to the liberal-strategy group, adjusted for the confounding effects of age, APACHE (acute physiology and chronic health evaluation) II score, and comorbid illness, was 1.07 (95% CI, 0.96 to 1.26; p = 0.43). The adjusted RR of extubation success associated with restrictive transfusion in the 219 patients who received mechanical ventilation for > 7 days was 1.1 (95% CI, 0.84 to 1.45; p = 0.47).

CONCLUSION

In this study, there was no evidence that a liberal RBC transfusion strategy decreased the duration of mechanical ventilation in a heterogeneous population of critically ill patients.

Is a low transfusion threshold safe in critically ill patients with cardiovascular diseases?

OBJECTIVE

To compare a restrictive red blood cell transfusion strategy with a more liberal strategy in volume-resuscitated critically ill patients with cardiovascular disease.

SETTING

Twenty-two academic and three community critical care units across Canada.

STUDY DESIGN

Randomized controlled clinical trial.

STUDY POPULATION

Three hundred fifty-seven critically ill patients with cardiovascular diseases from the Transfusion Requirements in Critical Care trial who had a hemoglobin concentration of <90 g/L within 72 hrs of admission to the intensive care unit.

INTERVENTIONS

Patients were randomized to a restrictive strategy to receive allogeneic red blood cell transfusions at a hemoglobin concentration of 70 g/L (and maintained between 70 and 90 g/L) or a liberal strategy to receive red blood cells at 100 g/L (and maintained between 100 and 120 g/L).

RESULTS

Baseline characteristics in the restrictive (n = 160) and the liberal group (n = 197) were comparable, except for the use of cardiac and anesthetic drugs (p <.02). Average hemoglobin concentrations (85 +/- 6.2 vs. 103 +/- 6.7 g/L; p <.01) and red blood cell units transfused (2.4 +/- 4.1 vs. 5.2 +/- 5.0 red blood cell units; p <.01) were significantly lower in the restrictive compared with the liberal group. Overall, all mortality rates were similar in both study groups, including 30-day (23% vs. 23%; p = 1.00), 60-day, hospital, and intensive care unit rates. Changes in multiple organ dysfunction from baseline scores were significantly less in the restrictive transfusion group overall (0.2 +/- 4.2 vs. 1.3 +/- 4.4; p =.02). In the 257 patients with severe ischemic heart disease, there were no statistically significant differences in all survival measures, but this is the only subgroup where the restrictive group had lower but nonsignificant absolute survival rates compared with the patients in the liberal group.

CONCLUSION

A restrictive red blood cell transfusion strategy generally appears to be safe in most critically ill patients with cardiovascular disease, with the possible exception of patients with acute myocardial infarcts and unstable angina.

A patient decision aid regarding antithrombotic therapy for stroke prevention in atrial fibrillation: a randomized controlled trial

CONTEXT

Decision aids are tools designed to help patients participate in the clinical decision-making process.

OBJECTIVE

To determine whether use of an audiobooklet (AB) decision aid explaining the results of a clinical trial affected the decision-making process of study participants.

DESIGN

Randomized controlled trial conducted from May 1997 to April 1998.

SETTING

Fourteen centers that participated in the Stroke Prevention in Atrial Fibrillation (SPAF) III trial.

PARTICIPANTS

A total of 287 patients from the SPAF III aspirin cohort study, in which patients with atrial fibrillation and a relatively low risk of stroke received 325 mg/d of aspirin and were followed up for a mean of 2 years.

INTERVENTION

At the end of SPAF III, participants were randomized to be informed of the study results with usual care plus use of an AB (AB group) vs usual care alone (control group). The AB included pertinent information to help patients decide whether to continue taking aspirin or switch to warfarin.

MAIN OUTCOME MEASURES

Patients' ability to make choices regarding antithrombotic therapy, and 6-month adherence to these decisions. Their knowledge, expectations, decisional conflict (the amount of uncertainty about the course of action to take), and satisfaction with the decision-making process were also measured.

RESULTS

More patients in the AB group made a choice about antithrombotic therapy than in the control group (99% vs 94%; P = .02). Patients in the AB group were more knowledgeable and had more realistic expectations about the risk of stroke and hemorrhage (in the AB group, 53%-80% correctly estimated different risks; in the control group, 16%-28% gave correct estimates). Decisional conflict and satisfaction were similar for the 2 groups. After 6 months, a similar percentage of patients were still taking their initial choice of antithrombotic therapy (95% vs 93%; P = .44).

CONCLUSIONS

For patients with atrial fibrillation who had participated in a major clinical trial, the use of an AB decision aid improved their understanding of the benefits and risks associated with different treatment options and helped them make definitive choices about which therapy to take. Further studies are necessary to evaluate the acceptability and impact of decision aids in other clinical settings.

A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group

BACKGROUND

To determine whether a restrictive strategy of red-cell transfusion and a liberal strategy produced equivalent results in critically ill patients, we compared the rates of death from all causes at 30 days and the severity of organ dysfunction.

METHODS

We enrolled 838 critically ill patients with euvolemia after initial treatment who had hemoglobin concentrations of less than 9.0 g per deciliter within 72 hours after admission to the intensive care unit and randomly assigned 418 patients to a restrictive strategy of transfusion, in which red cells were transfused if the hemoglobin concentration dropped below 7.0 g per deciliter and hemoglobin concentrations were maintained at 7.0 to 9.0 g per deciliter, and 420 patients to a liberal strategy, in which transfusions were given when the hemoglobin concentration fell below 10.0 g per deciliter and hemoglobin concentrations were maintained at 10.0 to 12.0 g per deciliter.

RESULTS

Overall, 30-day mortality was similar in the two groups (18.7 percent vs. 23.3 percent, P= 0.11). However, the rates were significantly lower with the restrictive transfusion strategy among patients who were less acutely ill -- those with an Acute Physiology and Chronic Health Evaluation II score of < or =20 (8.7 percent in the restrictive-strategy group and 16.1 percent in the liberal-strategy group; P=0.03) -- and among patients who were less than 55 years of age (5.7 percent and 13.0 percent, respectively; P=0.02), but not among patients with clinically significant cardiac disease (20.5 percent and 22.9 percent, respectively; P=0.69). The mortality rate during hospitalization was significantly lower in the restrictive-strategy group (22.3 percent vs. 28.1 percent, P=0.05).

CONCLUSIONS

A restrictive strategy of red-cell transfusion is at least as effective as and possibly superior to a liberal transfusion strategy in critically ill patients, with the possible exception of patients with acute myocardial infarction and unstable angina.

Risk of hemolytic uremic syndrome after sporadic Escherichia coli O157:H7 infection: results of a Canadian collaborative study. Investigators of the Canadian Pediatric Kidney Disease Research Center

OBJECTIVES

The objectives of this study were to better estimate the age-specific risks of hemolytic uremic syndrome (HUS) and hemolytic anemia after Escherichia coli O157:H7 infection among a representative cohort of both referred and nonreferred children with documented illness from the province of Alberta and to compare this with the rates in children evaluated at referral centers in the rest of Canada.

STUDY DESIGN

Children with HUS or E. coli O157:H7 gastroenteritis were eligible if they were < 15 years of age. Hemoglobin, blood smear, urinalysis, and serum creatinine were obtained 8 to 10 days after the onset of diarrhea to ascertain for hemolysis, anemia, thrombocytopenia, and renal injury. Subjects were monitored for 1 month.

RESULTS

From June 1991 to March 1994, HUS was diagnosed in 205 children. Of these 77% had evidence of E. coli O157:H7 infection. A further 582 children had E. coli O157:H7 gastroenteritis, of whom 18 had hemolytic anemia. The risk of HUS after E. coli O157:H7 infection in Alberta was 8.1% (95% confidence interval, 5.3 to 11.6) compared with 31.4% in referral centers in the rest of Canada. In Alberta the highest age-specific risk of HUS/hemolytic anemia was 12.9% in those < 5 years of age.

CONCLUSIONS

These data will help guide clinical care and provide a basis for estimating the sample sizes required in future treatment trials for the secondary prevention of HUS.

The impact of blinding on the results of a randomized, placebo-controlled multiple sclerosis clinical trial

In the randomized, placebo-controlled, physician-blinded Canadian cooperative trial of cyclophosphamide and plasma exchange, neither active treatment regimens (group I: i.v. cyclophosphamide and prednisone; group II: weekly plasma exchange, oral cyclophosphamide, and prednisone) were superior to placebo (group III: sham plasma exchange and placebo medications) using the blinded, evaluating neurologists' assessments of disease course (primary analysis). All patients were examined by both a blinded and an unblinded neurologist at each assessment in this trial. We compared the blinded and unblinded neurologists' judgment of treatment response and analyzed the clinical behavior of patients who correctly guessed their treatment. The unblinded (but not the blinded) neurologists' scores demonstrated an apparent treatment benefit at 6, 12, and 24 months for the group II patients (not group I or placebo; p < 0.05, two-tailed). There were no significant differences in the time to treatment failure or in the proportions of patients improved, stable, or worse between the group II and group III patients who correctly guessed their treatment assignments and those who did not. Physician blinding prevented an erroneous conclusion about treatment efficacy (false positive, type 1 error).