Schmidt J F, Jørgensen B C
Anesth Analg. 1984 Sep;63(9):841-3.
Because sodium citrate is known to increase both gastric pH and gastric volume while metoclopramide decreases gastric volume, we evaluated, in a double-blind randomized study, the effect of combining metoclopramide with sodium citrate on gastric pH and volume after induction of anesthesia in 60 female patients to determine whether gastric pH could be increased at the same time that gastric volume was decreased. All patients received 50-ml sodium citrate. To mimic standard anesthetic practice, all patients were premedicated: 20 patients received meperidine alone, 20 received meperidine plus 20-mg metoclopramide, and 20 received diazepam plus 20-mg metoclopramide. Metoclopramide failed to decrease median gastric volume or to increase the number of patients with gastric volumes less than 25 ml. There was no difference in median pH values in the three groups of patients. In patients receiving metoclopramide, the risk of pH values less than 2.5 was greater with gastric volumes less than 25 ml than in patients with volumes greater than or equal to 25 ml. We conclude that preoperative metoclopramide does not decrease gastric volume in patients premedicated with meperidine or diazepam and that when gastric volume was less than 25 ml the neutralizing effect of sodium citrate was lost.
由于已知柠檬酸钠会增加胃内pH值和胃容量，而甲氧氯普胺会减少胃容量，因此我们在一项双盲随机研究中评估了甲氧氯普胺与柠檬酸钠联合使用对60例女性患者麻醉诱导后胃内pH值和胃容量的影响，以确定在胃容量减少的同时胃内pH值是否能够升高。所有患者均接受了50毫升柠檬酸钠。为模拟标准麻醉操作，所有患者均接受了术前用药：20例患者仅接受哌替啶，20例接受哌替啶加20毫克甲氧氯普胺，20例接受地西泮加20毫克甲氧氯普胺。甲氧氯普胺未能降低胃容量中位数，也未能增加胃容量小于25毫升的患者数量。三组患者的pH值中位数没有差异。在接受甲氧氯普胺的患者中，胃容量小于25毫升时pH值小于2.5的风险高于胃容量大于或等于25毫升的患者。我们得出结论，术前使用甲氧氯普胺对接受哌替啶或地西泮术前用药的患者的胃容量没有降低作用，并且当胃容量小于25毫升时，柠檬酸钠的中和作用丧失。
