2013 - April R3 Journal Review
Dewilde WJM, et al. Use of clopidogrel with or without aspirin patients taking oral anticoagulant therapy and undergoing percutaneous coronary intervention: an open-label, randomized controlled trial. Lancet. 2013; 381:1107-15. This is a multicenter, open-label, randomized controlled trial that looked at the safety and efficacy of clopidogrel alone compared to clopidogrel with aspirin in patients who are already on oral anticoagulants and undergo PCI. The study included patients from 15 centers in Belgium and the Netherlands from 2008-2011. Inclusion criteria included age 18-80 years, a long-term indication for oral anticoagulation therapy (atrial fibrillation, mechanical heart valve or other) until at least one year after the study, a severe coronary lesion defined as at least 75% stenosis of angiography or fractional flow reserve lower than 0.80, with an indication for PCI. The primary endpoint was the occurrence of any bleeding episodes during 1-year follow-up. Each bleeding episode was further classified by TIMI criteria (minimal, minor, or major), GUSTO bleeding criteria (minor, moderate, severe) and BARC classification. Secondary endpoints included death, myocardial infarction, stroke, target vessel revascularization and stent thrombosis. In the end, 284 patients were randomly assigned to double therapy and 289 patients were assigned to triple therapy. Results for the primary endpoint at one-year showed 19.4% in the double therapy group and 44.4% of patients in the triple therapy group had any bleeding event, with a hazard ratio of 0.36 (95%CI 0.26-0.50) and p<0.0001. For both the TIMI and GUSTO classifications, inclusion of only major or severe bleeding was not statistically different between the double and triple therapy groups, but inclusion of major and minor (TIMI) and severe and moderate (GUSTO) showed a significantly high rate of bleeding episodes in the triple therapy group compared to double therapy. In addition, the triple therapy group required more blood transfusions than the double therapy group (9.5% vs 3.9%, respectively), with OR 0.39 (95%CI 0.17-0.84) and p=0.011. Cumulative incidence of secondary endpoints (death, MI, large-vessel revascularization, stroke, and stent thrombosis were reported in 11.1% in the double therapy vs 17.6% in the triple therapy, HR 0.60 (95%CI 0.38-0.94), p=0.025. Interestingly, the rates of thrombotic and thromboembolic events did not differ between patients who did or did not receive aspirin, but the authors noted that the study was not powered to detect such differences. Overall, the authors conclude that treatment with oral anticoagulation and clopidogrel was associated with a significantly lower risk of bleeding complications than was oral anticoagulants, clopidogrel and aspirin.
Jaehoon Oh, et al. Videographic Analysis of Glottic View with Increasing Cricoid Pressure Force. Ann Emerg Med. April 2013; 61(4):407-413. Past studies have had varying conclusions about the benefit of cricoid pressure during intubation. The goal of this study was to determine the effect of cricoid pressure on glottis view by analyzing the glottis view area with videography. Patients scheduled to undergo an elective surgery requiring intubation were screened. Exclusion criteria included younger than 18, history of surgery, trauma, or radiation of the neck, pregnancy and those with difficult airways (not defined). 277 subjects were assessed, 109 excluded, 107 refused, 11 have poor video quality or recorder error leaving 50 participating subjects. Sex, age, BMI, hyomental distance, hyothyroidal distance, mouth opening distance, and Mallampati were recorded. At the time of surgery patients were positioned in a similar sniffing position and anesthesia was induced with fentanyl and thiopental. Vecuronium was given for neuromuscular blockade, effects of which were confirmed by peripheral nerve stimulator. A Pentax-AWS video laryngoscope was inserted to record glottis view. A force measurement sensor was used to provide uniform cricoid pressure from 0-55 Newtons while an anesthesiologist recorded the view. The cricoid pressure was then removed and the patient was intubated. Force was linked to video view and the glottis view was measured. Results: Best glottic view was obtained at 0N (no pressure) for 20 patients, with 10 subjects at 5N, 4 at 10N, 4 at 15N, 3 at 20N, 1 at 25N, 1 at 30N, 2 at 35N, 1 at 40N and 45N, and 3 at 50N. Three subjects achieved total occlusion at 20N, and 9 had total occlusion at 50N. Conclusions: There was significant variability between patients, but increasing cricoid pressure usually worsened the glottis view. Limitations: Only one type of blade was used, which picks up the epiglottis and thus does not include obstruction by epiglottis, which has been shown to cause obstruction of the glottic view during cricoid pressure in other studies. This study looks only at view, not at difficulty of intubation as patients were not intubated while pressure was applied. Patients with difficult airways were excluded.