Vanner R G, Pryle B J, O'Dwyer J P, Reynolds F
Department of Anaesthetics, St Thomas' Hospital, London.
Anaesthesia. 1992 Nov;47(11):950-4. doi: 10.1111/j.1365-2044.1992.tb03196.x.
Upper oesophageal sphincter pressure was recorded with a Dent sleeve in 30 patients breathing nitrous oxide, oxygen and halothane. Twenty-three patients, after thiopentone induction, received suxamethonium and had their trachea intubated either before (group A, n = 11), or after (group B, n = 11), a study period of inhalational anaesthesia. Group C (n = 8) received an inhalational induction. Mean (SD) sphincter pressure after loss of consciousness was 8 (7) mmHg (group A), 6 (5) mmHg (group B) and 24 (13) mmHg (group C) increasing to 19 (7) mmHg in group A immediately after intubation. With an end-tidal halothane concentration of 1.5%, mean sphincter pressure in group B, 16 (7) mmHg, was significantly lower than in group A, 45 (21) mmHg (p < 0.001) and group C, 27 (14) mmHg (p < 0.05). Halothane had no dose-related effect on sphincter pressure. Insertion of a laryngeal mask in group C (n = 7) had no significant effect on sphincter pressure. Induction and maintenance of anaesthesia with halothane, unlike thiopentone or suxamethonium, maintained a degree of upper oesophageal sphincter tone, although three patients in this study had sphincter pressures of less than 10 mmHg and would therefore have been at risk of regurgitation in the presence of gastro-oesophageal reflux.
用Dent套管记录了30例吸入氧化亚氮、氧气和氟烷的患者的食管上括约肌压力。23例患者在硫喷妥钠诱导后，接受了琥珀酰胆碱并在吸入麻醉研究期之前（A组，n = 11）或之后（B组，n = 11）进行气管插管。C组（n = 8）接受吸入诱导。意识消失后的平均（标准差）括约肌压力在A组为8（7）mmHg，B组为6（5）mmHg，C组为24（13）mmHg，A组在插管后立即升至19（7）mmHg。在呼气末氟烷浓度为1.5%时，B组的平均括约肌压力为16（7）mmHg，显著低于A组的45（21）mmHg（p < 0.001）和C组的27（14）mmHg（p < 0.05）。氟烷对括约肌压力无剂量相关影响。C组（n = 7）插入喉罩对括约肌压力无显著影响。与硫喷妥钠或琥珀酰胆碱不同，用氟烷诱导和维持麻醉可保持一定程度的食管上括约肌张力，尽管本研究中有3例患者的括约肌压力低于10 mmHg，因此在存在胃食管反流的情况下有反流风险。
