Mathews H M, Wilson C M, Thompson E M, Moore J
Anaesthesia. 1986 Dec;41(12):1202-6. doi: 10.1111/j.1365-2044.1986.tb13004.x.
The gastric pH and volume were measured in 175 patients undergoing elective, and 313 undergoing emergency, obstetric procedures. Ranitidine 150 mg was administered orally every 6 hours in labour and at least 2 hours before elective Caesarean section. Patients received 20 ml of 8.4% sodium bicarbonate orally immediately prior to induction of anaesthesia. The combination of ranitidine and sodium bicarbonate produced marked alkalinisation of gastric contents (mean pH 8.9). The administration of sodium bicarbonate pre-operatively in patients who received ranitidine less than 2 hours before operation led to satisfactory elevation of gastric pH. Only four patients had a gastric pH less than 2.5, one patient refused any medication, two received only ranitidine and one patient had a long interval from administration of bicarbonate to aspiration of gastric contents. Gastric volumes were high in labouring patients (mean 84 ml) despite administration of ranitidine. The effectiveness of sodium bicarbonate as a single dose antacid therapy prior to obstetric anaesthesia requires further study.
对175例行择期产科手术和313例行急诊产科手术的患者进行了胃内pH值和容量的测量。分娩时及择期剖宫产术前至少2小时口服雷尼替丁150毫克，每6小时一次。患者在麻醉诱导前立即口服20毫升8.4%的碳酸氢钠。雷尼替丁和碳酸氢钠联合使用使胃内容物显著碱化（平均pH值8.9）。在术前少于2小时接受雷尼替丁治疗的患者中，术前给予碳酸氢钠可使胃内pH值满意升高。只有4例患者的胃内pH值低于2.5，1例患者拒绝用药，2例仅接受雷尼替丁治疗，1例患者从给予碳酸氢钠到抽取胃内容物的间隔时间较长。尽管使用了雷尼替丁，但分娩患者的胃容量仍较高（平均84毫升）。碳酸氢钠作为产科麻醉前单剂量抗酸治疗的有效性需要进一步研究。
