Nossov P C, Alfaro D V, Michaud M E, Winter L W, Laughlin R M, Moss S T
Walter Reed Army Institute of Research, Washington, District of Columbia, USA.
Retina. 1996;16(3):246-9. doi: 10.1097/00006982-199616030-00011.
A swine model of penetrating ocular trauma was used to determine the delivery of systemically administered cefazolin to the vitreous cavity of traumatized and nontraumatized eyes.
Thirty-one pigs received a scleral laceration to the right eye under anesthesia and then were given intravenous cefazolin every 8 hours. Seven pigs received nine doses at 17 mg/kg. Seven animals received three doses of 36 mg/kg, and six others received nine doses of this regimen. Six pigs received three doses of 79 mg/kg and five others received three doses of 190 mg/kg.
Vitreous levels of cefazolin averaged 15.6 micrograms/mL in traumatized eyes but were less than 1 microgram/mL in control eyes of animals receiving three doses at 190 mg/kg (P < or = 0.025). Mean serum concentration in these animals was 49.3 micrograms/mL. Vitreous levels were less than 1 microgram/mL in traumatized and control eyes in animals given lower doses of cefazolin (range, 17-79 mg/kg) despite multiple treatments over 2 and 3 days.
These data demonstrate that systemically delivered cefazolin achieves levels ten times the minimum inhibitory concentration for Staphylococcus epidermidis in injured eyes. Therapeutic intraocular levels can be obtained through intravenous dosing, provided that therapeutic serum concentrations are achieved.
采用猪穿透性眼外伤模型，以确定全身给药头孢唑林在受伤和未受伤眼玻璃体内的递送情况。
31头猪在麻醉下右眼行巩膜裂伤，然后每8小时静脉注射头孢唑林。7头猪接受9剂17mg/kg的药物。7只动物接受3剂36mg/kg的药物，另外6只接受该方案的9剂药物。6头猪接受3剂79mg/kg的药物，另外5头接受3剂190mg/kg的药物。
受伤眼玻璃体内头孢唑林水平平均为15.6微克/毫升，但在接受3剂190mg/kg药物的动物的对照眼中低于1微克/毫升（P≤0.025）。这些动物的平均血清浓度为49.3微克/毫升。在给予较低剂量头孢唑林（范围为17 - 79mg/kg）的动物中，尽管在2天和3天内进行了多次治疗，但受伤眼和对照眼的玻璃体内水平均低于1微克/毫升。
这些数据表明，全身给药的头孢唑林在受伤眼中达到的水平是表皮葡萄球菌最低抑菌浓度的10倍。只要达到治疗性血清浓度，通过静脉给药即可获得治疗性眼内浓度。
