Mahmud Saedon

The role of feedback in improving the effectiveness of workplace based assessments: a systematic review

BackgroundWith recent emphasis placed on workplace based assessment (WBA) as a method of formative performance assessment, there is limited evidence in the current literature regarding the role of feedback in improving the effectiveness of WBA. The aim of this systematic review was to elucidate the impact of feedback on the effectiveness of WBA in postgraduate medical training.MethodsSearches were conducted using the following bibliographic databases to identify original published studies related to WBA and the role of feedback: Medline (1950-December 2010), Embase (1980-December 2010) and Journals@Ovid (English language only, 1996-December 2010). Studies which attempted to evaluate the role of feedback in WBA involving postgraduate doctors were included.Results15 identified studies met the inclusion criteria and minimum quality threshold. They were heterogeneous in methodological design. 7 studies focused on multi source feedback, 3 studies were based on mini-clinical evaluation exercise, 2 looked at procedural based assessment, one study looked at workplace based assessments in general and 2 studies looked at a combination of 3 to 6 workplace based assessments. 7 studies originated from the United Kingdom. Others were from Canada, the United States and New Zealand. Study populations were doctors in various grades of training from a wide range of specialties including general practice, general medicine, general surgery, dermatology, paediatrics and anaesthetics. All studies were prospective in design, and non-comparative descriptive or observational studies using a variety of methods including questionnaires, one to one interviews and focus groups.ConclusionsThe evidence base contains few high quality conclusive studies and more studies are required to provide further evidence for the effect of feedback from workplace based assessment on subsequent performance. There is, however, good evidence that if well implemented, feedback from workplace based assessments, particularly multisource feedback, leads to a perceived positive effect on practice.

Risk stratification by pre-operative cardiopulmonary exercise testing improves outcomes following elective abdominal aortic aneurysm surgery: a cohort study

BackgroundIn 2009, the NHS evidence adoption center and National Institute for Health and Care Excellence (NICE) published a review of the use of endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs). They recommended the development of a risk-assessment tool to help identify AAA patients with greater or lesser risk of operative mortality and to contribute to mortality prediction.A low anaerobic threshold (AT), which is a reliable, objective measure of pre-operative cardiorespiratory fitness, as determined by pre-operative cardiopulmonary exercise testing (CPET) is associated with poor surgical outcomes for major abdominal surgery. We aimed to assess the impact of a CPET-based risk-stratification strategy upon perioperative mortality, length of stay and non-operative costs for elective (open and endovascular) infra-renal AAA patients.MethodsA retrospective cohort study was undertaken. Pre-operative CPET-based selection for elective surgical intervention was introduced in 2007. An anonymized cohort of 230 consecutive infra-renal AAA patients (2007 to 2011) was studied. A historical control group of 128 consecutive infra-renal AAA patients (2003 to 2007) was identified for comparison.Comparative analysis of demographic and outcome data for CPET-pass (AT ≥ 11 ml/kg/min), CPET-fail (AT < 11 ml/kg/min) and CPET-submaximal (no AT generated) subgroups with control subjects was performed. Primary outcomes included 30-day mortality, survival and length of stay (LOS); secondary outcomes were non-operative inpatient costs.ResultsOf 230 subjects, 188 underwent CPET: CPET-pass n = 131, CPET-fail n = 35 and CPET-submaximal n = 22. When compared to the controls, CPET-pass patients exhibited reduced median total LOS (10 vs 13 days for open surgery, n = 74, P < 0.01 and 4 vs 6 days for EVAR, n = 29, P < 0.05), intensive therapy unit requirement (3 vs 4 days for open repair only, P < 0.001), non-operative costs (£5,387 vs £9,634 for open repair, P < 0.001) and perioperative mortality (2.7% vs 12.6% (odds ratio: 0.19) for open repair only, P < 0.05). CPET-stratified (open/endovascular) patients exhibited a mid-term survival benefit (P < 0.05).ConclusionIn this retrospective cohort study, a pre-operative AT > 11 ml/kg/min was associated with reduced perioperative mortality (open cases only), LOS, survival and inpatient costs (open and endovascular repair) for elective infra-renal AAA surgery.

Temporal artery biopsy for giant cell arteritis: retrospective audit.

Objectives Temporal artery biopsy (TAB) is performed in suspected cases of sight-threatening giant cell arteritis (GCA). We aimed to determine the feasibility of TAB in patients who are suspected of having GCA. Design, setting and participants A retrospective audit of all patients undergoing TAB at a single teaching hospital between 2005 and 2011, identified from the histopathology database. Main outcome measures (1) Clinical profile and biochemical criteria associated with positive histology. (2) Proportion of negative histology patients who were commenced on steroid therapy. Results One hundred and fifty-three TAB were performed (mean age 70.8 years, men:women = 3:2, 110 Caucasian: 43 Asian). Thirty-two biopsies were positive for GCA and 121 were negative. In total, 68 (61%) of 112 negative TAB patients were clinically diagnosed with GCA despite histological findings (P < 0.001). Nine out of 153 biopsies were non-arterial. Histologically positive TAB patients were of higher mean age (77.1 [95% CI 74.5–79.7] versus 69.1 [95% CI 66.7–71.6]; P < 0.001) and had a higher erythrocyte sedimentation rate (ESR) (60 [95% CI 46.1–73.9] versus 39.8 [95% CI 34.2–45.3]; P < 0.01)] than those with negative histology. Conclusions Raised ESR and higher age may be the most useful indicators of GCA. Many histologically negative individuals were nevertheless clinically diagnosed and managed as GCA.

Registry Report on Kinetics of Rescue Antiplatelet Treatment to Abolish Cerebral Microemboli After Carotid Endarterectomy

Background and Purpose— Cerebral microemboli signals (MES) are associated with increased risk of acute stroke syndromes. We compared the effects on cerebral microemboli after carotid endarterectomy of tirofiban with dextran-40. Methods— We used transcranial Doppler ultrasound to study transient MES acutely after carotid endarterectomy between August 2000 and December 2010 in 128 subjects refractory to preoperative antiplatelet treatment. Antithrombotic treatment was given for MES ≥50 hour−1 (tirofiban: 40 patients [age 74 ± 1 {SEM}, males 27, and white 38]; dextran-40: 34 patients [age 69 ± 2, males 22, white 30]). In 54 patients with MES <50 hour−1 (age 71 ± 1, male 36, white 52), MES were monitored during their spontaneous resolution (controls). Data are median (interquartile range). Results— The time to 50% reduction in MES (tirofiban 23 minutes [15–28]; dextran-56 [43–83]; controls 30 [22–38]; P<0.001, Kruskal-Wallis analysis) and for complete MES resolution (tirofiban 68 minutes [53–94]; dextran-113 [79–146]; controls 53 [49–68]; P<0.001, Kruskal-Wallis analysis) were shorter with tirofiban. The early cardiovascular event rate was similar with tirofiban compared with controls but increased in patients who received dextran. Conclusions— These findings suggest that transcranial Doppler-directed tirofiban therapy is more effective than dextran-40 in suppression of cerebral microemboli after carotid endarterectomy.

Endovascular Versus Surgical Revascularization for the Management of Chronic Mesenteric Ischemia.

Background: Chronic mesenteric ischemia (CMI) can be treated with surgical revascularization (SR) or endovascular revascularization (ER). Materials and Methods: Systematic review of 12 studies comparing ER and SR in CMI. Primary end point was perioperative (30 days) survival. A secondary composite end point consisted of perioperative mortality, nonfatal cardiac events, nonfatal stroke, and nonfatal bowel ischemia. Further end points included late survival, primary patency, and symptom improvement. Results: The cumulative odds ratio (OR) for perioperative mortality was 0.78 (95% confidence interval [CI]: 0.40-1.50, P = .45) and 0.56 (95% CI: 0.28-1.11, P = .10) for the composite end point. The cumulative OR for survival after the 30th day was 0.83 (95% CI: 0.47-1.46), P = .51. Late primary patency was reported in 8 studies, with a cumulative OR of 3.57 (95% CI: 1.83-6.97, P = .0002)—favoring SR. Conclusion: In the first meta-analysis to compare ER and SR in CMI, there were no differences in mortality and morbidity. Patency rates were better following SR.

Obesity as an Independent Predictor of Outcome after Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND Obesity is increasingly common in patients referred for the management of an abdominal aortic aneurysm (AAA). Evidence of the effect of obesity on outcomes after endovascular repair (EVAR) is not well established. We sought to compare the immediate and midterm outcomes of elective EVAR between obese and nonobese patients in a case control study. METHODS Patients undergoing elective EVAR were divided in 2 groups: obese (defined as a body mass index [BMI] ≥30 kg/m(2)) and nonobese (mean BMI [kg/m(2)] ± SD: 33 ± 1 vs 25 ± 3). Both groups were case-matched for age, sex, smoking, and AAA diameter. One hundred fifty-nine patients were included (mean age: 69 ± 9 years; 10 women [9%]; mean BMI: 28 ± 5 kg/m(2); 53 were obese and 106 were nonobese). All aneurysms were successfully excluded. Mean follow-up was 34 ± 13 months. RESULTS All patients who developed a complication within the perioperative period (≤30 days) were obese (P = 0.01). Thirteen patients (8.2%) died during follow-up (8 obese versus 5 nonobese; P = 0.76). Survival and non-procedure-related morbidity did not differ significantly between the obese and nonobese groups (P = 0.64 and 0.16; log-rank test). BMI was not associated with mortality or non-procedure-related morbidity on multivariate analysis (mortality-hazard ratio: 1.0 [95% confidence interval: 0.9-1.2]; P = 0.37; non-procedure-related morbidity-hazard ratio: 1.0 [95% confidence interval: 0.9-1.1], P = 0.2). CONCLUSIONS This is the first case control study to assess the independent impact of obesity in the outcome after EVAR. No difference was documented with regards to mortality or non-aneurysm-related morbidity.

Prospective validation study of transorbital Doppler ultrasound imaging for the detection of transient cerebral microemboli.

Transient cerebral microemboli are independent biomarkers of early risk of ischaemic stroke in acute carotid syndromes. Transcranial Doppler imaging (TCD) through the temporal bone is the standard method for detection of cerebral microemboli, but an acoustic temporal bone window for TCD is not available in around one in seven patients. Transorbital Doppler imaging (TOD) has been used when TCD is not possible. The aim of this study was to validate the use of TOD against TCD for detecting cerebral microemboli.

ABCD 2 risk score does not predict the presence of cerebral microemboli in patients with hyper-acute symptomatic critical carotid artery stenosis

Introduction ABCD2 risk score and cerebral microemboli detected by transcranial Doppler (TCD) have been separately shown to the predict risk of recurrent acute stroke. We studied whether ABCD2 risk score predicts cerebral microemboli in patients with hyper-acute symptomatic carotid artery stenosis. Participants and methods We studied 206 patients presenting within 2 weeks of transient ischaemic attack or minor stroke and found to have critical carotid artery stenosis (≥50%). 86 patients (age 70±1 (SEM: years), 58 men, 83 Caucasian) had evidence of microemboli; 72 (84%) of these underwent carotid endarterectomy (CEA). 120 patients (age 72±1 years, 91 men, 113 Caucasian) did not have microemboli detected; 102 (85%) of these underwent CEA. Data were analysed using X 2 and Mann–Whitney U tests and receiver operating characteristic (ROC) curves. Results 140/206 (68%: 95% CI 61.63 to 74.37) patients with hyper-acute symptomatic critical carotid stenosis had an ABCD2 risk score ≥4. There was no significant difference in the NICE red flag criterion for early assessment (ABCD2 risk score ≥4) for patients with cerebral microemboli versus those without microemboli (59/86 vs 81/120 patients: OR 1.05 ABCD2 risk score ≥4 (95% CI 0.58 to 1.90, p=0.867)). The ABCD2 risk score was <4 in 27 of 86 (31%: 95% CI 21 to 41) embolising patients and in 39 of 120 (31%: 95% CI 23 to 39) without cerebral microemboli. After adjusting for pre-neurological event antiplatelet treatment (APT), area under the curve (AUC) of ROC for ABCD2 risk score showed no prediction of cerebral microemboli (no pre-event APT, n=57: AUC 0.45 (95% CI 0.29 to 0.60, p=0.531); pre-event APT, n=147: AUC 0.51 (95% CI 0.42 to 0.60, p=0.804)). Conclusions The ABCD2 score did not predict the presence of cerebral microemboli or carotid disease in over one-quarter of patients with symptomatic critical carotid artery stenosis. On the basis of NICE guidelines (refer early if ABCD2 ≥4), assessment of high stroke risk based on ABCD2 scoring may lead to inappropriate delay in urgent treatment in many patients.