Zanuzzo Felipe S, Teixeira-Neto Francisco J, Thomazini Camila M, Takahira Regina K, Conner Bobbi, Diniz Miriely S
Department of Anesthesiology, Faculdade de Medicina, Universidade Estadual Paulista (UNESP), CEP 18618-970, Botucatu, Brazil.
Departments of Veterinary Surgery and Anesthesiology, Clinical Veterinary Sciences.
J Vet Emerg Crit Care (San Antonio). 2015 Jul-Aug;25(4):512-20. doi: 10.1111/vec.12336. Epub 2015 Jun 25.
To compare the effects of dipyrone, meloxicam, and of the combination of these drugs on hemostasis in dogs.
Prospective, blinded, randomized crossover study.
Research laboratory at a veterinary teaching hospital.
Six adult dogs.
Animals received 4 intravenous treatments with 15-day washout intervals: control (physiological saline, 0.1 mL/kg), meloxicam (0.2 mg/kg), dipyrone (25 mg/kg), and dipyrone-meloxicam (25 and 0.2 mg/kg, respectively). A jugular catheter was placed for drug injection and for collecting samples for whole blood platelet aggregation (WBPA) and thromboelastometry assays at baseline, 1, 2, 3, 5, and 8 hours after treatment administration. The percent change from baseline of lag time and of the area under the curve (AUC) of impedance changes in response to collagen-induced platelet activation were recorded during WBPA. Thromboelastometry-derived parameters included clotting time, clot formation time, alpha-angle, and maximum clot firmness. The buccal mucosal bleeding time was evaluated by a blinded observer at baseline, 1, 3, and 5 hours after treatment injection.
No significant changes in WBPA and thromboelastometry were recorded in the control treatment. Dipyrone significantly (P < 0.05) increased the lag time for 2 hours and decreased the AUC for 3 hours after injection. Meloxicam did not alter WBPA. Dipyrone-meloxicam significantly increased lag time for 2 hours and decreased the AUC for 5 hours after treatment injection. Experimental treatments did not differ from the control treatment for thromboelastometry and buccal mucosal bleeding time.
While meloxicam does not alter hemostasis by the methods evaluated, dipyrone inhibits platelet aggregation for up to 3 hours. Meloxicam-dipyrone combination causes more prolonged inhibition of platelet function than dipyrone alone. Decreased platelet aggregation induced by dipyrone and dipyrone-meloxicam does not appear to impact the viscoelastic properties of the blood clot nor increase the risk of bleeding in dogs without preexisting hemostatic disorders.
比较安乃近、美洛昔康以及这两种药物联合使用对犬止血功能的影响。
前瞻性、盲法、随机交叉研究。
一家兽医教学医院的研究实验室。
6只成年犬。
动物接受4次静脉注射治疗，每次治疗间隔15天进行洗脱期：对照组（生理盐水，0.1 mL/kg）、美洛昔康（0.2 mg/kg）、安乃近（25 mg/kg）以及安乃近-美洛昔康（分别为25 mg/kg和0.2 mg/kg）。在给药前及给药后1、2、3、5和8小时，通过颈静脉导管进行药物注射，并采集样本用于全血血小板聚集（WBPA）和血栓弹力图分析。在WBPA过程中，记录胶原诱导血小板活化后滞后时间和阻抗变化曲线下面积（AUC）相对于基线的变化百分比。血栓弹力图衍生参数包括凝血时间、凝块形成时间、α角和最大凝块硬度。由一名盲法观察者在给药前及给药后1、3和5小时评估颊黏膜出血时间。
对照组治疗中，WBPA和血栓弹力图未记录到显著变化。安乃近在注射后显著（P < 0.05）延长滞后时间2小时，并在3小时内降低AUC。美洛昔康未改变WBPA。安乃近-美洛昔康在治疗注射后显著延长滞后时间2小时，并在5小时内降低AUC。实验性治疗在血栓弹力图和颊黏膜出血时间方面与对照组治疗无差异。
虽然美洛昔康通过所评估的方法未改变止血功能，但安乃近可抑制血小板聚集长达3小时。美洛昔康-安乃近联合使用比单独使用安乃近对血小板功能的抑制作用持续时间更长。安乃近和美洛昔康-安乃近引起的血小板聚集减少似乎并未影响血凝块的粘弹性特性，也未增加无预先存在止血障碍的犬的出血风险。
