An exploratory investigation of the use and effects of academic instant messaging groups among university students.

The use of instant messaging groups for various academic purposes is a rising, but largely understudied, trend in higher education institutions. In the present study we investigate the use purposes and outcomes of three types of academic instant messaging groups or AIMGs. Formal AIMGs are created and managed by teaching staff, class AIMGs are created by students and joined by all members of a particular class, and study AIMGs are smaller groups created by students that know each other personally or collaborate in group assignments. To advance understanding of the role of these groups in students' wellbeing and academic development, we pose research questions concerning their associations with academic performance, academic stress, and students' course experiences. We adopt an exploratory frame and survey methodology to collect data from a large sample of undergraduate students (n = 1752). Our findings indicate that, at the institution where data were collected, high rates of AIMG participation is the norm, with class AIMGs emerging as particularly popular. We find statistically significant interaction between formal and study AIMGs and academic performance, as well as between study AIMGs and academic stress. Participation in these groups also predicts students' social experience of a learning community, as well as their perception of the teaching they receive. Throughout, however, the observed effects are small and their practical significance is questioned.

[Pediatric heart surgery in developing countries. Twenty years experience of La Chaine de L'espoir (Chain of Hope)]. / La chirurgie cardiaque pédiatrique dans les pays en voie de développement. Vingt ans d'expérience de la chaîne de l'Espoir.

Because of their high incidence, cardiac disorders in children are now a public health issue. These children require multidisciplinary management, but surgery is sometimes unavoidable. The two most frequent types of cardiac disorder in children are congenital defects and rheumatic valve disease. La Chaine de l'Espoir (Chain of Hope) is present in more than 30 countries in Africa, Asia and the Middle East. Due to the socio-economic context and lack of technical resources, pediatric heart surgery has several particular characteristics in developing countries. Infants rarely undergo cardiac surgery, given the complexity of their management and particularly the need for intensive care. Another specificity is the need to limit treatment to reparatory or conservative methods. Surgery is rarely attempted in terminally ill patients. Costs must be kept to a minimum, and this is why we have optedfor local manufacture of mitral rings, led by Daniel Roux. After 20 years of practice we have found that regional hospitals are the smallest structures that can offer acceptable results in terms of patient care and professional training

Off-task media use in academic settings: cycles of self-regulation failure.

Objective: The effects of off-task media use in academic settings on academic performance have been widely reported. In response, a range of interventions have been proposed. Among these have been calls for the cultivation of more effective self-regulation of media use. Against this backdrop, the present study investigates students' self-regulation of off-task media in academic settings. Method: A series of focus groups was conducted involving 30 undergraduate students at a large, South African university. A combination of inductive and deductive analysis was conducted on the basis of prominent theories of self-regulation. Results: The presences of off-task media in academic settings create ongoing experiences of goal-conflict and many students become trapped in cycles of repeated self-regulation failure, ultimately culminating in procrastination. Conclusions: We refer to this phenomenon as the media procrastination cycle and argue that it contributes to negative affect, stress, and anxiety among students.

Results of radiofrequency ablation for permanent atrial fibrillation in patients undergoing mitral valve surgery.

OBJECTIVES: The study aim was to evaluate the safety and feasibility of radiofrequency ablation for the surgical treatment of permanent atrial fibrillation in patients with degenerative mitral valve disease. DESIGN: From August 2000 to August 2003, 40 consecutive patients (mean age 69.0 +/- 9.3 years) with permanent atrial fibrillation and degenerative mitral valve disease underwent surgical radiofrequency ablation in conjunction with 22 mitral valve repairs and 18 mitral valve replacements. The mean duration of chronic AF was 5.1 +/- 3.4 years. The completeness of follow-up was 100%. The mean follow-up time was 4.6 +/- 2.0 years (range 0 to 7.8 years). RESULTS: Thirty-day mortality was 2.5% (1 patient), the cause of death was cardiac failure. Cardiac failure and temporary A-V block were the most common postoperative complications. Both occurred in 10% (4 patients). No complication was related to the ablation procedure. At discharge, 65% (26/40) of the patients were in sinus rhythm. Overall incidence of sinus rhythm at the end of the follow-up was 56.4% (22/39).The 1-, 3- and 5-year survival was 97.5%, 91.8% and 85.9%, respectively. CONCLUSION: Mitral valve surgery combined with radiofrequency ablation is a safe and effective procedure in patients with permanent atrial fibrillation and degenerative mitral valve disease. The result is encouraging in restoring sinus rhythm, and an excellent postoperative survival rate can be achieved.

Treatment of a fistula at the distal anastomosis after Bentall operation with endoluminal covered stent.

A 25-year-old Marfan patient was operated on for an acute type A aortic dissection that was complicated twice by false aneurysms at the distal suture line. At the third episode a covered endoprosthesis was inserted in the ascending aorta between the coronary ostia and the inominate artery. The postoperative course was uneventful and a control computed tomographic scan showed complete occlusion of the false aneurysm. This attractive technique should be considered versus an open-heart operation in selected patients.

Type-A acute aortic dissection: combined operation plus stent management.

When the port of entry of acute type-A aortic dissection is at the level of the horizontal portion of the aortic arch, the latter should be replaced by a prosthesis. To avoid performing this difficult procedure in an emergency situation, we place a stent in the aortic arch. Then we replace the ascending aorta by a prosthesis.

Endovascular treatment of thoracic aortic fistulas.

Aortoesophageal and aortobronchial fistulas constitute a problem in therapy because of the high rates of morbidity and mortality associated with operation. From May 1996 to March 2000, we treated by an endovascular procedure one aortoesophageal and three aortobronchial fistulas. There was no postoperative death. We noted one peripheral vascular complication that required a surgical procedure, one postoperative confusion, and one inflammatory syndrome. In one case, because of a persistent leakage after 21 months, we had to implant a second endovascular stent graft. A few weeks later the reopening of this patient's esophageal fistula led to his death by mediastinitis 25 months after the first procedure. The few cases published seem to bear out the interest, observed in our 4 patients, of an endovascular approach to treat complex lesions such as fistulas of the thoracic aorta especially in emergency or palliative cases.

Homemade mitral ring.

A simple and quick technique to fashion a mitral ring was developed using a stainless steel wire covered by a Gore-Tex strip. This technique allows a 15-fold reduction in the cost of a mitral ring compared with commercially available rings. As such, cardiac surgery becomes more readily available to patients in developing countries such as Africa and Asia. These homemade rings were implanted in 6 patients with similar results to commercially available rings.

Wrapping procedure for stanford type a acute aortic dissection: is there an indication for surgery without a cardiopulmonary bypass?

A wrapping procedure for acute type A aortic dissection was performed on six elderly patients at high risk for conventional surgery. Aortic valve insufficiency was mild, with no malperfusion syndrome. A Teflon plaque or Dacron vascular prosthesis was passed around the aorta and tightened from the coronary ostia to the innominate artery. No severe neurologic complications or deaths occurred in the postoperative period. Computed tomography and magnetic resonance imaging imaging during follow-up showed aortic diameters had stabilized in all patients.

Ebstein's anomaly assessed by real-time 3-D echocardiography.

The outcome of patients with Ebstein's malformation depends mainly on the severity of the tricuspid valve malformation. Accurate description of the tricuspid anatomy by two-dimensional echocardiography remains difficult. We applied real-time three-dimensional echocardiography to 3 patients with Ebstein's anomaly. Preoperative and postoperative descriptions of the tricuspid valve were obtained from views taken inside the right ventricle. Surface of the leaflets as well as the commissures were obtained by three-dimensional echocardiography. Real time three-dimensional echocardiography is a promising tool, providing new views that will help to evaluate the ability and efficiency of surgical valve repair in patient with Ebstein's malformation.

Ropivacaine and fentanyl concentrations in patient-controlled epidural analgesia during labor: a volume-range study.

UNLABELLED: We enrolled nulliparous women in induced labor in a randomized study to determine whether increasing the concentration of the solution used in a patient-controlled epidural analgesia (PCEA) device was required as labor progressed. Patients were assigned to 6 groups (n = 25 in each group), receiving ropivacaine/fentanyl in concentrations of either 0.1%/0.5 microg/mL or 0.2%/1 microg/mL via a PCEA pump. Three groups received boluses of 12, 16, or 20 mL dilute solution in early labor (uterine contractions every 3 min and 4-cm cervical dilation) then 6, 8, and 10 mL concentrated solution in late labor. Three other groups received boluses of 12, 16, or 20 mL dilute solution during both periods. The lockout interval was 25 min. The primary outcome was time until the first request for staff-administered analgesia supplement. Hourly assessments included pain scores on a visual analog scale (VAS) graded from 0 to 10, satisfaction scores, arterial blood pressure, motor block intensity, and the upper sensory level of epidural anesthesia. Patients, midwives, and the observer were unaware of study solutions and PCEA settings. The maximum pain score was defined as the highest score experienced by each patient during each period. Duration of analgesia was defined as the time from the start of each period to the first injection of rescue analgesia and was compared using a survival analysis. There were no differences among the groups with regard to demographic and obstetric variables, arterial blood pressure, motor block intensity, upper sensory level, or satisfaction scores. At least 75% of the women rated their satisfaction as either good or excellent during each period. During late labor, the maximum pain score was lower in the group receiving 20 mL dilute solution compared with the group receiving 6 mL concentrated solution. Maximum pain score was not significantly different between 20 mL dilute solution and 10 mL concentrated solution (difference between VAS values = -0.4; 95% confidence limits, -1.599 and 0.799; P = 0.5055). During late labor, the duration of analgesia was longer in groups receiving 20 mL dilute solution (99 +/- 4 min) (mean +/- SD) than in those receiving 12 mL (77 +/- 30 min) and 16 mL (80 +/- 23 min). Duration of analgesia did not differ between groups receiving 20 mL and 10 mL (92 +/- 23 min) or between groups receiving 12 mL and 6 mL (78 +/- 30 min) of each respective solution. Duration of analgesia was longer in the groups receiving 8 mL concentrated solution (94 +/- 16 min) than in those receiving 16 mL dilute solution. We concluded that 0.1%/0.5 microg/mL ropivacaine/fentanyl was effective throughout labor when 20 mL was injected with each PCEA demand. With 16 mg ropivacaine and 8 microg fentanyl, the duration of analgesia was prolonged by doubling the concentration when labor became active. When 12 mg ropivacaine and 6 microg fentanyl were injected at each demand, analgesia was less satisfactory and doubling the concentration was not clinically effective. These results suggest that the effectiveness of PCEA is dependent on drug mass rather than the volume or concentration administered with each successful pump demand. IMPLICATIONS: There is no clinical reason for increasing the concentration of the patient-controlled epidural analgesia (PCEA) solution when labor becomes active provided that an effective dose is already being administered with each demand. The quality of PCEA depends on the drug mass given with each demand rather than the concentration of the pump solution.

Transthoracic three-dimensional echocardiography prior to closure of atrial septal defects in children.

AIMS: Our aims were to use transthoracic three-dimensional echocardiography to assess the morphology of atrial septal defects in children prior to closure, and to compare the three-dimensional echocardiographic data with transcatheter and surgical findings. METHODS AND RESULTS: We used transthoracic three-dimensional echocardiography in 62 consecutive patients, aged from 2 to 18 years, with atrial septal defects, measuring the maximal diameter and the extent of the rims. Subsequent to the study, we referred 42 patients for transcatheter closure, the rims being measured at greater than 4 mm. We found a good correlation between the maximal diameter of the defect as measured at transthoracic three-dimensional echocardiography and using a balloon (y = 3.45 - 0.73x; r = 0.78; p < 0.0001), the mean difference between the measurements being 2.4 +/- 2.8 mm. Successful closure with the Amplatzer septal occluder, having a mean size of 22 +/- 4 mm, was achieved in 95% of the patients. Of the original cohort, 20 patients were referred for surgical closure. In these patients, the inferior rim had been deemed insufficient in 5, the postero-superior rim in 6, and the postero-inferior rim in 9. Complete agreement was found when the deficiency of the rim as judged using transthoracic three-dimensional echocardiography was compared with intraoperative findings. The correlation between measurements of the deficiency of the rim achieved by transthoracic three-dimensional echocardiography and at surgery was excellent (y = 0.2 + 0.98x; r = 0.93; p < 0.0001), the mean difference between the measurements being no more than 0.6 +/- 0.4 mm. CONCLUSIONS: Transthoracic three-dimensional echocardiography proved accurate in measuring the maximal diameter and rims of atrial septal defects within the oval fossa. This non-invasive method will be valuable in selecting children for transcatheter or surgical closure of such defects.