Is it safe to cover the left subclavian artery when placing an endovascular stent in the descending thoracic aorta?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the left subclavian artery may be safely covered with a descending thoracic aortic stent without a prior carotid-subclavian artery bypass or transposition procedure. Altogether 2612 abstracts were identified. Forty-five non-randomized control trials and 213 non-controlled papers were found using the reported search and all these were read in full to search for coverage of the left subclavian artery. From these papers, 20 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We identified 20 studies with more than 10 cases of left subclavian artery coverage without prior revascularisation. Aggregating the data from all these studies we found 498 covered left subclavian arteries. Complications included 13 strokes (2.6%), 8 cases of paraplegia or paraparesis (1.6%) and 6 endoleaks due to subclavian backflow (1.2%). Of note there were 51 cases of ischaemia or other symptoms attributable to poor blood flow (10%), which resulted in 20 post-procedural revascularisations (4%). In three studies the mean pressure drop in the left arm was between 36 and 48 mmHg after left subclavian occlusion. We conclude that coverage of the left subclavian artery has a low, but not insignificant, incidence of side-effects. This incidence must be balanced with the urgency of the procedure and may be acceptable in emergency or salvage situations. However, in non-emergency cases we recommend that the carotid arteries, the vertebral arteries and the Circle of Willis are fully assessed by tests such as duplex ultrasound, angiography, CT or MRI scanning. An absent right vertebral artery, diseased carotid arteries or an incomplete Circle of Willis is a contraindication to left subclavian artery coverage without prior transposition or bypass grafting of the left subclavian artery.

Oral calcitriol versus oral alfacalcidol for the treatment of secondary hyperparathyroidism in patients receiving hemodialysis: a randomized, crossover trial.

BACKGROUND: Secondary hyperparathyroidism is a common complication in patients with chronic kidney disease and treatment with vitamin D analogues is a mainstay of therapy. Although oral calcitriol and alfacalcidol are used extensively in Canada, there is little published data comparing equal doses of these agents. OBJECTIVES: To compare the effect of equal doses of oral calcitriol and alfacalcidol on intact parathyroid hormone concentrations (iPTH) in the treatment of secondary hyperparathyroidism due to chronic kidney disease. Secondary endpoints included serum 1,25-dihydroxyvitamin D3, calcium and phosphate concentrations, achievement of target iPTH concentrations, and need for phosphate binder dose increases. METHODS: Five adult hemodialysis subjects who were naA ve to vitamin D analogues and had iPTH concentrations > or = 20 pmol/L were enrolled in a prospective, randomized 16-week crossover pilot study. Subjects were randomized to either oral calcitriol or oral alfacalcidol 0.75 mcg three times weekly for six weeks. After a four-week washout period, patients were crossed over to the alternate drug for six weeks. RESULTS: Oral calcitriol significantly suppressed iPTH after six weeks of therapy (p=0.003), while no significant change in iPTH was observed with oral alfacalcidol. CONCLUSIONS: This small randomized crossover study provides preliminary evidence that equal doses of oral alfacalcidol and calcitriol may demonstrate differences in iPTH suppression during the first six weeks in dialysis patients treated for secondary hyperparathyroidism. Further comparative trials are required to confirm this finding and to determine whether important differences in parathyroid hormone suppression exist between oral calcitriol and alfacalcidol beyond the six-week period. Key words: Vitamin D analogues, alfacalcidol, calcitriol, secondary hyperparathyroidism, renal dialysis.

What interventions should pharmacists employ to impact health practitioners' prescribing practices?

OBJECTIVE: To determine which interventions are effective in influencing health practitioners' prescribing practices and explore differences in intervention complexity, setting, sustainability, cost effectiveness, and impact on patient outcomes. METHODS: A systematic search for English-language systematic reviews was performed in MEDLINE, Cumulative Index of Nursing and Allied Health Literature, EMBASE, and the Cochrane Library from the date of inception to July 2005 using search terms in accordance with Cochrane recommendations. Included reviews were required to clearly report a search strategy, inclusion/exclusion criteria, literature assessment criteria, and methods for synthesizing or summarizing information and references. Two reviewers independently identified studies for inclusion, assessed study quality, and extracted relevant information. Interventions were classified as consistently effective, inconsistently effective, and effectiveness uncertain. RESULTS: Thirty-four of 4585 titles reviewed met the inclusion criteria. Quality scores ranged from 70% to 100%. Consistently effective interventions included reminders (manual and computerized), audit and feedback, educational outreach visits, organizational strategies, and patient-mediated interventions. Inconsistently effective interventions included computer decision support systems and educational meetings. Multi-faceted interventions were consistently shown to be more efficacious than single interventions. Limited data precluded exploration of the effects of interventions in different settings, sustainability of effect, cost effectiveness, and patient clinical outcomes. CONCLUSIONS: Interventions that are most effective for impacting prescribing practice include audit and feedback, reminders, educational outreach visits, and patient-mediated interventions. To maximize impact, pharmacists' efforts to positively impact prescribing practices should focus on these intervention types rather than relying primarily on passive didactics or dissemination of guidelines.

Patient-controlled versus nurse-controlled analgesia after cardiac surgery--a meta-analysis.

BACKGROUND: Patient-controlled analgesia (PCA) has been advocated as superior to conventional nurse-controlled analgesia (NCA) with less risk to patients. This systematic review and meta-analysis sought to determine whether PCA improves clinical and resource outcomes when compared with NCA. METHODS: A comprehensive search was undertaken to identify all randomized controlled trials of PCA vs NCA. Medline, Cochrane Library, Embase, and conference abstract databases were searched from the date of their inception to August 2005. The primary postoperative outcome was defined as mean visual analogue scale (VAS) scores. Secondary postoperative outcomes included cumulative morphine equivalents, intensive care unit (ICU) and hospital length of stay, postoperative nausea and vomiting, sedation, respiratory depression, and all-cause mortality. Odds ratios or weighted mean differences (WMD) and their 95% confidence intervals (CI) were calculated for discrete and continuous outcomes, respectively. RESULTS: Ten randomized trials involving 666 patients were included. Compared to NCA, PCA significantly reduced VAS at 48 hr (WMD -0.73, 95% CI -1.19, -0.27), but not at 24 hr (WMD -0.19, 95% CI -0.61, 0.24). Cumulative morphine equivalents consumed were significantly increased at 24 hr (WMD 6.84 mg, 95% CI 0.97, 12.72 mg), and at 48 hr (WMD 10.46 mg 95% CI 2.02, 18.9 mg) for PCA compared with NCA. Ventilation times, length of ICU stay, length of hospital stay, patient satisfaction scores, sedation scores, and incidence of postoperative nausea and vomiting, respiratory depression, severe pain, discontinuations, and death were not significantly different between groups, but these outcomes were generally under-reported. CONCLUSIONS: In postcardiac surgical patients, PCA increases cumulative 24 and 48 hr morphine consumption, and improves 48-hr VAS compared with NCA.

NSAID-analgesia, pain control and morbidity in cardiothoracic surgery.

OBJECTIVE: While narcotics remain the backbone of perioperative analgesia, the adjunctive role of other analgesics, including non-steroidal anti-inflammatory drugs (NSAIDs), is being recognized increasingly. This meta-analysis sought to determine whether adjunctive NSAIDs improve postoperative analgesia and reduce cumulative narcotic requirements. METHODS: A comprehensive search was undertaken to identify all randomized trials, in cardiothoracic patients, of NSAIDs plus narcotics vs narcotics without NSAIDs. Medline, Cochrane Library, EMBASE, and abstract databases were searched up to September 2005. The primary outcome was visual analogue scale (VAS) pain score. Secondary outcomes included 24-hr cumulative morphine-equivalents, rescue medications required, mortality, myocardial infarction, atrial fibrillation, stroke, renal failure, hospital readmissions, and in-hospital costs. RESULTS: Twenty randomized trials involving 1,065 patients were included. A significant reduction in 24-hr VAS pain score was found in patients receiving NSAIDs [weighted mean difference (WMD) -0.91 points, 95% confidence interval (CI) -1.48 to -0.34 points]. In addition, patients required significantly less morphine-equivalents in the first 24 hr (WMD -7.67 mg, 95% CI -8.97 to -6.38 mg). No significant difference was found with respect to mortality [odds ratio (OR) 0.19, 95% CI 0.01 to 4.22], myocardial infarction (OR 0.71, 95% CI 0.09 to 5.71), renal dysfunction (OR 0.95, 95% CI 0.37 to 2.46), or gastrointestinal bleeding (OR 0.96, 95% CI 0.13 to 7.09). CONCLUSION: In patients less than 70 yr of age undergoing cardiothoracic surgery, the adjunctive use of NSAIDs with narcotic analgesia reduces 24-hr VAS pain score and narcotic requirements.

Does off-pump coronary artery bypass reduce mortality, morbidity, and resource utilization when compared with conventional coronary artery bypass? A meta-analysis of randomized trials.

The authors undertook a meta-analysis of 37 randomized trials (3369 patients) of off-pump coronary artery bypass surgery versus conventional coronary artery bypass surgery. No significant differences were found for 30-day mortality (odds ratio [OR], 1.02; 95% confidence interval [CI], 0.58-1.80), myocardial infarction (OR, 0.77; 95%CI, 0.48-1.26), stroke (OR, 0.68; 95%CI, 0.33-1.40), renal dysfunction, intraaortic balloon pump, wound infection, rethoracotomy, or reintervention. However, off-pump coronary artery bypass surgery significantly decreased atrial fibrillation (OR, 0.58; 95%CI, 0.44-0.77), transfusion (OR, 0.43; 95%CI, 0.29-0.65), inotrope requirements (OR, 0.48; 95%CI, 0.32-0.73), respiratory infections (OR, 0.41; 95%CI, 0.23-0.74), ventilation time (weighted mean difference, -3.4 h; 95%CI, -5.1 to -1.7 h), intensive care unit stay (weighted mean difference, -0.3 days; 95%CI -0.6 to -0.1 days), and hospital stay (weighted mean difference, -1.0 days; 95%CI -1.5 to -0.5 days). Patency and neurocognitive function results were inconclusive. In-hospital and 1-yr direct costs were generally higher for conventional coronary artery bypass surgery versus off-pump coronary artery bypass surgery. Therefore, this meta-analysis demonstrates that mortality, stroke, myocardial infarction, and renal failure were not reduced in off-pump coronary artery bypass surgery surgery; however, selected short-term and mid-term clinical and resource outcomes were improved compared with conventional coronary artery bypass surgery.