Niwa Hitoshi, Tanimoto Ai, Sugimura Mitsutaka, Morimoto Yoshinari, Hanamoto Hiroshi
Department of Dental Anesthesiology, Osaka University Graduate School of Dentistry, Osaka, Japan.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006 Dec;102(6):e1-9. doi: 10.1016/j.tripleo.2006.03.014. Epub 2006 Sep 25.
During implant surgery, a large amount of local anesthetics containing epinephrine are often required, and the resulting cardiovascular effects of administered epinephrine are not negligible. On the other hand, sedation has wide applications in implant surgery. Nitrous oxide, propofol, or midazolam are commonly used as sedative drugs, and each has also its own cardiovascular effects. The objective of this study was to investigate the cardiovascular effects of epinephrine on patients under sedation with nitrous oxide, propofol, or midazolam.
We studied 9 healthy volunteers. They received epinephrine infusion at a nominal rate of 10, 25, or 50 ng/kg per minute under sedation with 30% nitrous oxide inhalation, 4 mg/kg per hour intravenous propofol or 0.2 mg/kg per hour intravenous midazolam. For each, hemodynamic response and blood pressure and heart rate variability were measured.
When epinephrine was infused alone at 50 ng/kg per minute, heart rate (HR) and cardiac index (CI) increased by 19.5% and 40.7%, respectively. Propofol suppressed the epinephrine-induced increase in CI. During midazolam infusion, the highest dose of epinephrine caused a 37.5% increase in HR, which was significantly higher than for epinephrine infusion alone. This response was accompanied by the reduction in high-frequency power of heart rate variability, suggesting decreased parasympathetic activity. Nitrous oxide had no influence on the cardiovascular response to epinephrine.
Increased cardiovascular activity due to epinephrine can be alleviated by propofol. However, midazolam and nitrous oxide are of no advantage for stabilizing the hemodynamic status of the patient. Intravenous sedation with propofol is useful during oral surgical procedures in which a large amount of epinephrine is required.
在种植手术过程中，通常需要大量含肾上腺素的局部麻醉剂，而注入肾上腺素所产生的心血管效应不容忽视。另一方面，镇静在种植手术中有广泛应用。氧化亚氮、丙泊酚或咪达唑仑常用作镇静药物，且每种药物也都有其自身的心血管效应。本研究的目的是调查肾上腺素对接受氧化亚氮、丙泊酚或咪达唑仑镇静的患者的心血管效应。
我们研究了9名健康志愿者。他们在吸入30%氧化亚氮、静脉注射4mg/kg每小时的丙泊酚或静脉注射0.2mg/kg每小时的咪达唑仑镇静状态下，以每分钟10、25或50ng/kg的名义速率接受肾上腺素输注。对于每一位志愿者，测量血流动力学反应以及血压和心率变异性。
当单独以每分钟50ng/kg的速率输注肾上腺素时，心率（HR）和心脏指数（CI）分别增加了19.5%和40.7%。丙泊酚抑制了肾上腺素引起的CI增加。在输注咪达唑仑期间，最高剂量的肾上腺素使HR增加了37.5%，这显著高于单独输注肾上腺素时的情况。这种反应伴随着心率变异性高频功率的降低，表明副交感神经活动减少。氧化亚氮对肾上腺素的心血管反应没有影响。
丙泊酚可减轻肾上腺素引起的心血管活动增加。然而，咪达唑仑和氧化亚氮在稳定患者血流动力学状态方面没有优势。在需要大量肾上腺素的口腔外科手术中，静脉注射丙泊酚进行镇静是有用的。
