Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.
Department of Anesthesiology, Zi-Gong Fourth People's Hospital, Zigong, Sichuan, China.
Medicine (Baltimore). 2024 Jun 7;103(23):e38421. doi: 10.1097/MD.0000000000038421.
The goal of this study was to evaluate the dose-response relationship between dexmedetomidine and propofol in sedating patients and to determine the optimal dosage of dexmedetomidine during gastrointestinal endoscopy.
One hundred fifty patients were divided into 5 groups, each receiving a loading dose of dexmedetomidine (0.4, 0.6, 0.8, 1.0 µg/kg) or saline, with propofol for sedation. The median effective concentration (EC50) of propofol was calculated using the modified Dixon up-and-down approach. Adverse effects, vital signs, procedure, and recovery times were recorded.
The EC50 of propofol in groups NS, D0.4, D0.6, D0.8, and D1.0 were 3.02, 2.44, 1.97, 1.85, and 1.83 µg/mL, respectively. Heart rate in the dexmedetomidine groups decreased more than the NS group (P < .001). The mean arterial pressure (MAP) in the NS group experienced a decline compared to groups D0.8 and D1.0 when the plasma concentration and effect-site concentration reached equilibrium. Additionally, the respiratory rate was found to be lower in groups NS, D0.4, D0.6, and D0.8 (P < .05). Recovery time in groups D0.8 and D1.0 was longer than the NS group (P < .05). Bruggemann comfort scales score was higher in group D1.0 (P < .05). No significant difference was found in the incidences of hypotension and bradycardia, and the dose of ephedrine and atropine. Respiratory depression was significantly reduced in groups D0.8 and D1.0 compared to the NS group.
A single dose of 0.6 to 0.8 µg/kg of dexmedetomidine should be recommended in combination with propofol for gastrointestinal endoscopy. And the EC50 of propofol is 1.97 to 1.85 µg/mL.
本研究旨在评估右美托咪定和丙泊酚镇静患者的剂量-反应关系，并确定胃肠内镜检查中右美托咪定的最佳剂量。
将 150 例患者分为 5 组，每组给予右美托咪定（0.4、0.6、0.8、1.0μg/kg）或生理盐水负荷剂量，然后用丙泊酚镇静。采用改良 Dixon 上下法计算丙泊酚的半数有效浓度（EC50）。记录不良反应、生命体征、手术和恢复时间。
NS 组、D0.4 组、D0.6 组、D0.8 组和 D1.0 组丙泊酚的 EC50 分别为 3.02、2.44、1.97、1.85 和 1.83μg/ml。与 NS 组相比，右美托咪定组的心率下降更为明显（P<0.001）。当血浆浓度和效应部位浓度达到平衡时，NS 组的平均动脉压（MAP）较 D0.8 组和 D1.0 组下降。此外，与 NS 组、D0.4 组、D0.6 组和 D0.8 组相比，呼吸频率更低（P<0.05）。与 NS 组相比，D0.8 组和 D1.0 组的恢复时间更长（P<0.05）。D1.0 组的 Bruggemann 舒适度评分较高（P<0.05）。低血压和心动过缓的发生率以及麻黄碱和阿托品的剂量无显著差异。与 NS 组相比，D0.8 组和 D1.0 组的呼吸抑制明显减少。
对于胃肠内镜检查，建议将 0.6 至 0.8μg/kg 的右美托咪定与丙泊酚联合使用。此时丙泊酚的 EC50 为 1.97 至 1.85μg/ml。
