Tatekawa S, Yukioka H, Fujimori M, Shiba K, Kubota Y, Hamai R, Satoh E, Ogata A, Kawasaki O
Department of Anesthesiology and Intensive Care Medicine, Osaka City University Medical School.
Masui. 1990 Dec;39(12):1619-25.
Famotidine, an H2-antagonist, is frequently used for prevention of acid aspiration in surgical patients. Intravenous as well as intramuscular administration of famotidine has proved effective to reduce gastric acid secretion during anesthesia. However, the onset and duration of action of famotidine following intravenous administration has not been extensively investigated. In the present study on 89 patients undergoing elective surgery, the effects of famotidine 20 mg administered intravenously 5-30 min before endotracheal intubation on pH and volume of gastric contents aspirated 0, 1, 2, and 4 hrs after tracheal intubation and immediately after extubation through nasogastric tube were compared with the effects of the drug administered intramuscularly one hour before endotracheal intubation. Famotidine administered intramuscularly 5-14 min before endotracheal intubation produced inadequate suppression of gastric secretion after tracheal intubation. In contrast, intravenous famotidine given 15-30 min before tracheal intubation, as well as the intramuscular administration of famotidine as premedication, effectively decreased gastric fluid volume and increased gastric pH. Suppression of gastric secretion by intravenous and intramuscular famotidine continued for over 4 hours. Intravenous famotidine has a rapid onset and a long duration of depressant action on gastric secretion, thus reducing the risk of aspiration pneumonitis during and after general anesthesia.
法莫替丁是一种H2拮抗剂，常用于预防外科手术患者的胃酸误吸。静脉注射和肌肉注射法莫替丁已被证明在麻醉期间可有效减少胃酸分泌。然而，静脉注射法莫替丁后的起效时间和作用持续时间尚未得到广泛研究。在本项针对89例择期手术患者的研究中，将气管插管前5 - 30分钟静脉注射20毫克法莫替丁对气管插管后0、1、2和4小时以及拔管后立即通过鼻胃管吸出的胃内容物pH值和体积的影响，与气管插管前1小时肌肉注射该药的效果进行了比较。气管插管前5 - 14分钟肌肉注射法莫替丁在气管插管后对胃酸分泌的抑制作用不足。相比之下，气管插管前15 - 30分钟静脉注射法莫替丁以及作为术前用药肌肉注射法莫替丁，均能有效减少胃液体积并提高胃pH值。静脉注射和肌肉注射法莫替丁对胃酸分泌的抑制作用持续超过4小时。静脉注射法莫替丁起效迅速，对胃酸分泌的抑制作用持续时间长，从而降低了全身麻醉期间及之后发生误吸性肺炎的风险。
