RESUMO
Objective: To investigate the impact of discontinued dual antiplatelet therapy(DAPT) of aspirin combining clopidogrel within 5 days on peri-operative bleeding in patients with coronary artery bypass grafting (CABG). Methods: A total of 2012 patients with off-pump CABG were retrospectively enrolled in our study including 1506 male and the mean age was at 61.92 years. All patients received regular DAPT previously and discontinued the medication≤5 days due to emergency or prior limited CABG. Based on the days from discontinued DAPT to operation, the patients were divided into 6 groups: 0-day group, n=220, 1-day group, n=240, 2-day group, n=360, 3-day group, n=332, 4-day group, n=428 and 5-day group, n=432. Relationships between risk factors of bleeding and discontinued DAPT time were studied. Results: Bleeding was defined by BARC (bleeding academic research consortium) standard. The incidences of bleeding events in 0-day group, 1-day group, 2-day group, 3-day group, 4-day group and 5-day group showed a decreasing trend as 29.1%, 24.6%,19.4%, 13.0%, 14.5% and 13.0% respectively, P<0.01. Post-operative chest drainage volume≥2L within 24h (P=0.13) and intracranial bleeding (P=0.60) had no obvious tendency changes; occurrence rates of 48h peri-operative transfusion≥5 U whole blood or red blood cells (P<0.01) and re-operation(P<0.01) had a decreasing trend by prolonged time of discontinued medication. The minor endpoint events were similar. Compared to (3-5) days discontinued medication, the patients with (0-2) days discontinued DAPT were with the higher incidences of overall bleeding, re-operation and 5U transfusion, the differences had statistical meaning. Conclusion: The incidence of bleeding presented a decreasing trend by prolonged time of discontinued DAPT before CABG;transfusion and re-operation had the statistical meaning for bleeding. Discontinued medication less than 3 days may increase bleeding events and therefore, in high risk patients, prior CABG discontinued medication should be more than 3 days.
RESUMO
To provide theoretical and practical basis for the successful formulation design of physically-mixed inhalation dry powder of proteins and peptides, related references were collected, analyzed and summarized. In this review drug micronization technology and commonly used carriers for inhalation dry powder preparation were introduced. For proteins and peptides, supercritical fluid technology and spray-drying are more suitable because of their capabilities of keeping drug activity. Being approved by U. S. Food and Drug Administration, lactose has been extensively used as carriers in many inhalation products. Formulation and process factors influencing drug deposition in the lung, including carrier properties, drug-carrier ratio, blending order, mixing methods, mixing time and the interaction between drug and carrier, were elucidated. The size, shape and surface properties of carries all influence the interaction between drug and carrier. Besides, influence of micromeritic properties of the dry powder, such as particle size, shape, density, flowability, charge, dispersibility and hygroscopicity, on drug deposition in the lung was elaborated. Among these particle size plays the most crucial role in particle deposition in the lung. Moreover, based on the mechanisms of powder dispersity, some strategies to improve drug lung deposition were put forward, such as adding carrier fines, adding adhesive-controlling materials and reprocessing micronized drug. In order to design physically-mixed inhalation dry powder for proteins and peptides with high lung deposition, it is essential to study drug-carriers interactions systematically and illustrate the potential influence of formulation, process parameters and micromeritic properties of the powder.