Kinetics of Plasma Cell-Free DNA and Creatine Kinase in a Canine Model of Tissue Injury.

BACKGROUND: Cell-free DNA (cfDNA) comprises short, double-stranded circulating DNA sequences released from damaged cells. In people, cfDNA concentrations correlate well with disease severity and tissue damage. No reports are available regarding cfDNA kinetics in dogs. OBJECTIVES/HYPOTHESIS: Cell-free DNA will have a short biological half-life and would be able to stratify mild, moderate, and severe tissue injury. Our study aims were to determine the kinetics and biological half-life of cfDNA and to contrast them with those of creatine kinase (CK). ANIMALS: Three groups of 10 dogs undergoing open ovariohysterectomy, surgery for cranial cruciate ligament rupture (CCLR), or hemilaminectomy. METHODS: Plasma for cfDNA and CK analysis was collected at admission, at induction of anesthesia, postsurgery (time 0) and at 6, 12, 24, 36, 48, 60, and 72 hours after surgery. RESULTS: The biological half-life of plasma cfDNA and CK were 5.64 hours (95% confidence interval [CI 95], 4.36-7.98 hours) and 28.7 hours (CI95, 25.3-33.3 hours), respectively. In the hemilaminectomy group, cfDNA concentrations differed significantly from admission at 6-12 hours after surgery. Creatine kinase activity differed among the surgical groups and reached a peak 6 hours after surgery. In the ovariohysterectomy and CCLR groups, plasma CK activity 72 hours after surgery did not differ from admission activity of the ovariohysterectomy group. In contrast, in the hemilaminectomy group, plasma CK activity after 72 hours did not return to the ovariohysterectomy group admission activity. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma CK activity has a longer biological half-life than previously thought. In contrast to plasma CK activity, cfDNA has a short half-life and could be a useful marker for peracute severe tissue injury.

A novel approach to improve undergraduate surgical teaching.

BACKGROUND: Undergraduate surgery is at an important crossroads. Many departments report significant difficulties delivering effective teaching. Our student feedback indicated a dated surgical curriculum lacking structure, quality and uniformity. We report on a new "blended" approach employing a combination of professional DVDs, case based discussions, online material and traditional bedside teaching designed to provide structure, standardization, and equality of learning . METHODS: Year 4 students who had undertaken the new course and year 5 students who had participated in the traditional teaching programme were compared. Students completed a 20 item questionnaire about their experiences of the surgical teaching programme. RESULTS: One hundred and seventy-one year 4 (70%) and 148 year 5 students (66%) responded. Domains relating to "Overall Satisfaction with the course", "Approval of innovative teaching methods and interactivity" and "Satisfaction with the clarity of course information" showed improvements when comparing the new and old programmes. However bedside teaching was not rated as highly in the new programme (p<0.05). CONCLUSION: This blended approach has resulted in improved student understanding and engagement. The apparent compromise of bedside teaching may be a reflection of higher expectations. We believe that a similar blended approach has the potential to re-invigorate surgical teaching elsewhere.

A comparison between randomly alternating imaging, normal laparoscopic imaging, and virtual reality training in laparoscopic psychomotor skill acquisition.

OBJECTIVES: To evaluate virtual reality as a laparoscopic training device in helping surgeons to automate to the "fulcrum effect" by comparing it to time-matched training programs using randomly alternating images (ie, y-axis inverted and normal laparoscopic) and normal laparoscopic viewing conditions. METHODS: Twenty-four participants (16 females and 8 males), were randomly assigned to minimally invasive surgery virtual reality (MIST VR), randomly alternating (between y-axis inverted and normal laparoscopic images), and normal laparoscopic imaging condition. Participants were requested to perform a 2-minute laparoscopic cutting task before and after training. RESULTS: In the test trial participants who trained on the MIST VR performed significantly better than those in the normal laparoscopic and randomly alternating imaging conditions. CONCLUSION: The results show that virtual reality training may provide faster skill acquisition with particular reference to automation of the fulcrum effect. MIST VR provides a new way of training laparoscopic psychomotor surgical skills.

Discriminative validity of the Minimally Invasive Surgical Trainer in Virtual Reality (MIST-VR) using criteria levels based on expert performance.

BACKGROUND: Increasing constraints on the time and resources needed to train surgeons have led to a new emphasis on finding innovative ways to teach surgical skills outside the operating room. Virtual reality training has been proposed as a method to both instruct surgical students and evaluate the psychomotor components of minimally invasive surgery ex vivo. METHODS: The performance of 100 laparoscopic novices was compared to that of 12 experienced (>50 minimally invasive procedures) and 12 inexperienced (<10 minimally invasive procedures) laparoscopic surgeons. The values of the experienced surgeons' performance were used as benchmark comparators (or criterion measures). Each subject completed six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR) three times. The outcome measures were time to complete the task, number of errors, economy of instrument movement, and economy of diathermy. RESULTS: After three trials, the mean performance of the medical students approached that of the experienced surgeons. However, 7-27% of the scores of the students fell more than two SD below the mean scores of the experienced surgeons (the criterion level). CONCLUSIONS: The MIST-VR system is capable of evaluating the psychomotor skills necessary in laparoscopic surgery and discriminating between experts and novices. Furthermore, although some novices improved their skills quickly, a subset had difficulty acquiring the psychomotor skills. The MIST-VR may be useful in identifying that subset of novices.

Voluntary euthanasia in Northern Ireland: general practitioners' beliefs, experiences, and actions.

BACKGROUND: There has been much recent interest in the press and among the profession on the subject of euthanasia and physician-assisted suicide. The BMA recently conducted a 'consensus conference' over the internet to collect views on physician-assisted suicide. Any surveys to date have addressed a variety of specialties; however, no recent surveys have looked at general practitioner (GP) attitudes and experiences. AIM: To explore the attitudes of GPs in Northern Ireland towards the issue of patient requests for euthanasia, their nature, and doctors' experiences of such requests. METHOD: An anonymous, confidential postal survey of all (1053) GP principals in Northern Ireland. RESULTS: Seventy per cent of responders believe that passive euthanasia is both morally and ethically acceptable. Fewer (49%) would be prepared to take part in passive euthanasia. However, over 70% of physicians responding consider physician-assisted suicide and voluntary active euthanasia to be wrong. Thirty per cent of responders have received requests from patients for euthanasia in the past five years. One hundred and seven doctors gave information about these requests. Thirty-nine out of 54 patient requests for passive euthanasia had been complied with, as had one of 19 requests for physician-assisted suicide and four out of 38 patient requests for active euthanasia. Doctors perceived the main reasons why patients sought euthanasia was because of fear of loss of dignity and fear of being a burden to others. CONCLUSIONS: While the majority of GPs support passive euthanasia, they, in common with those who approve of assisted suicide and active euthanasia, often express a reluctance to take part in such actions. This may reflect the moral, legal, and emotional dilemmas doctors encounter when facing end-of-life decisions.

Body weight, fluid, electrolyte, and hormonal changes in horses competing in 50- and 100-mile endurance rides.

OBJECTIVE: To investigate effects of prolonged exercise on fluid and electrolyte losses in horses competing in 50- and 100-mile endurance competitions, with emphasis on recovery. ANIMALS: Changes in body weight (BW); PCV; serum osmolality; plasma total protein, lactate, aldosterone, and serum electrolyte concentrations; and exchangeable cation content were measured in 12 and 7 horses before and after and before, during, and after successful completion of 50- and 100-mile endurance rides, respectively. PROCEDURE: BW was measured by use of a portable load bar scale, and blood samples were collected during the hour before ride start, at ride finish, and after approximately 2 and 18 hours (overnight) of recovery for horses competing in the 50-mile ride. For horses competing in the 100-mile ride, BW was measured and blood samples were collected at the start; after 50, 67, and 84 miles of the ride; at the finish; and after approximately 12 hours (overnight) of recovery. RESULTS: BW decreased by (mean +/- SEM) 3.6 +/- 0.0% and 4.9 +/- 0.8% in horses that successfully completed rides of 50 and 100 miles, respectively. After the overnight recovery period, BW was 4.3 +/- 0.5% and 3.9 +/- 0.8% lower than preride values for horses performing the 50- and 100-mile rides, respectively. A decrease in plasma volume during the ride was reflected by an increase in plasma total protein concentration, but both measures returned to preride values after overnight recovery. Serum osmolality and serum electrolyte concentrations decreased and aldosterone concentration increased during prolonged exercise. Aldosterone concentration peaked after overnight recovery. CONCLUSION: Despite apparent rapid return of plasma volume and ionic composition to near normal values, substantial depletion of body fluid and electrolyte stores persists after an overnight recovery period in horses that successfully complete 50 or 100 miles of endurance competition.

Referrals to hospital by general practitioners: a study of compliance and communication.

To determine the extent of non-attendance at first hospital appointments 269 hospital referrals made in one practice over 14 weeks were analysed retrospectively. Non-attendance was more likely among patients referred to outpatient departments than to casualty or for admission. Fifteen per cent (41/269) of all patients and 20% (33/167) of outpatients failed to keep their initial appointments. Prolonged waiting times from referral to appointment were significantly related to non-attendance. Twenty weeks after the last referral had been made no communication had been received by the practice for 24% (61/252) of all referral letters received by the hospital. Minimum delays to appointments and improved communication between hospitals and general practitioners would help general practitioners to make appropriate referrals and improve compliance.

Brisk walking, fitness, and cardiovascular risk: a randomized controlled trial in primary care.

STUDY OBJECTIVE: To examine the effects of 30 min of self-paced, non-supervised, brisk walking, 5 days per week on the health and fitness of people aged 50-65 years. DESIGN: Randomized controlled trial. Members of the intervention group (n = 21) were directed to walk briskly for 30 min, 5 days per week, for 12 weeks. Individuals were given the choice to complete the 30 min of walking in one session or in shorter bouts of no less than 10 min. They were asked to record in a diary the time spent walking and the number of steps taken during a single walk using a pedometer. Participants in the control group (n = 10) were asked to maintain their habitual lifestyle and not change their activity or dietary habits. Measurements of body mass index (BMI), waist/hip ratio (WHR), blood pressure, functional capacity, total cholesterol, triglyceride, and lipoprotein subfractions were taken before and after the program. Changes in 10-year risk estimate for coronary heart disease and stroke were calculated using Framingham risk equations. SETTING: Three urban general practices patients: 31 healthy, sedentary 50- to 65-year-old participants recruited following contact by their general practitioner. MAIN RESULTS: The mean time spent walking by the intervention group was 27.72 (+/-9.79) min/day: their adherence to the protocol was 90.3%. Significant decreases in systolic and diastolic blood pressure, reduction in stroke risk, and increased functional capacity were found within the walking group between baseline and 12-week measurements. No changes were found in these parameters within the control group. Significant reductions in 10-year risk of CHD were observed in both groups. No significant changes were found in lipid levels or anthropometric measurements in either group. CONCLUSIONS: The study provides evidence for the benefit to fitness and cardiovascular risk of the "30-min brisk walking, 5 days a week" message to people aged 50-65 years who participated in an unsupervised home-based walking program. Further study to overcome the problem of poor recruitment and determine the minimum effective dose of exercise to improve cardiovascular risk prediction scores is required.

Computer based learning in general practice--options and implementation.

A survey of the 30 departments of general practice in the UK revealed that only three are currently making use of any form of computer based learning materials for teaching their undergraduate students. One of the reasons for the low level of usage is likely to be the relatively poor availability of suitable courseware and lack of guidance as to how to utilise what is available. This short paper describes the types of courseware that are available and the advantages and disadvantages of using acquired courseware as opposed to writing your own. It also considers alternative strategies for making computer based learning (CBL) courseware available to students.

Preparing tomorrow's doctors: the impact of a special study module in medical informatics.

BACKGROUND: In response to the call for more informatics teaching in the medical curriculum, an elective special study module has been offered to first-year students at Queen's University since 1997. OBJECTIVES: To assess the impact of a medical informatics course in terms of the use of skills acquired and attitudes held about information technology (IT) in medicine. METHODS: A postal structured questionnaire was sent to all 30 students who took the medical informatics special study module in 1997 and to all 29 students who took the module in 1998, plus an age and sex-matched group of controls in each year. Main outcome measures included attitudes to the role of IT in medicine and declared frequency of use of various software packages. RESULTS: Compared with the control group, those taking the module felt less confident initially with computers. There was a high level of positive attitude to computers in medicine following the course, in both study and control groups. There was a significantly greater use of word-processing (P=0.001) and presentation packages (P=0.0005) amongst third-year students compared with second-year students, but there was no significant difference in this regard between those taking the module and controls. CONCLUSIONS: Students' use of computer technology and IT skills, is more influenced by the demands of the overall curriculum than by undertaking a single module in medical informatics. A special study module may, however, provide valuable support by performing a 'remedial function'. The authors found the module a useful first step in the process of introducing medical informatics to the core curriculum.

A randomized controlled trial using instant photography to diagnose and manage dermatology referrals.

BACKGROUND: Fifteen percent of GP consultations are for dermatological conditions; 4% of these are referred to a dermatologist. There are long waiting lists for dermatology appointments. This study examines the value of instant photography in managing dermatology referrals. OBJECTIVE: The purpose of our study was to compare outcomes of referral for dermatology appointments between patients whose referral letters do or do not include instant photograph(s). METHODS: Patients (136), referred to a dermatologist by GPs in two urban health centres, were randomly allocated to study and control groups. Instant photographs, taken by the GP, were included in the referral letters. Control group patients were given out-patient appointments in the usual way. The numbers of study group patients needing an appointment for diagnosis or management and with a changed diagnosis after face-to-face consultation were recorded. Waiting time from referral to appointment or management plan was recorded for both groups. RESULTS: For 63% of the study group (45/71), a diagnosis and a management plan were made without the patient requiring an appointment. This included 38% (27/71) who, after diagnosis and initial management, needed an appointment and 25% (18/71) who did not. The remainder of the study group (37%; 26/71) required a face-to-face consultation. The mean time for formulation of a management plan for patients without an appointment was 17 days (SD = 11); waiting times for appointments in study and control groups were similar (mean 55 days; SD = 40). CONCLUSIONS: Instant photography is helpful in managing dermatology referrals and offers the potential to reduce numbers requiring an out-patient appointment by 25%.