Patterson K W, Noonan N, Keeling N W, Kirkham R, Hogan D F
Department of Anaesthesia, St. James's Hospital, Dublin, Ireland.
J Clin Anesth. 1995 Mar;7(2):136-40. doi: 10.1016/0952-8180(94)00042-3.
To compare the effects on oxygen saturation as measured by pulse oximetry (SpO2) and ECG changes of endoscopy alone, sedation followed by endoscopy, and sedation followed by endoscopy with supplemental oxygen (O2) during upper gastrointestinal (GI) endoscopy.
Randomized trial.
Outpatient gastroenterology clinic at a university medical center.
58 healthy patients scheduled for outpatient upper GI endoscopy, with no clinical evidence of respiratory disease.
Patients were randomly allocated to three groups: Group 1 received no benzodiazepines before endoscopy and breathed room air throughout (n = 18), Group 2 received midazolam intravenously (i.v.) before endoscopy and breathed room air throughout (n = 20), and Group 3 received i.v. midazolam and 2 L/min O2 through nasal cannulae during endoscopy (Group 3; n = 20).
Data collection, which included heart rate, cardiac rhythm, and SpO2 were recorded at seven intervals: baseline, topical anesthesia of the oropharynx, mouth gag insertion, endoscope insertion, biopsy, endoscope removal, and five minutes postendoscopy. In Group 2, mean SpO2 decreased after midazolam was administered and remained depressed during endoscopy (p < 0.05). After midazolam was given, Group 2 patients differed significantly from patients in Groups 1 and 3 (p < 0.05).
The use of hypnotic doses of benzodiazepines is the primary factor responsible for the reduced oxygenation seen during endoscopy. Neither the presence of the endoscope alone nor the use of midazolam with supplemental O2 caused a decreased oxygenation. This study also suggests that the routine use of benzodiazepines is unnecessary when the endoscopy is of short duration, and the endoscopist employs good topicalization of the oropharynx. In patients who require sedation for endoscopy, O2 administration prevents hypoxemia.
比较上消化道内镜检查时单纯内镜检查、镇静后内镜检查以及镇静后内镜检查并补充氧气对脉搏血氧饱和度（SpO2）的影响和心电图变化。
随机试验。
大学医学中心的门诊胃肠病诊所。
58例计划进行门诊上消化道内镜检查的健康患者，无呼吸系统疾病的临床证据。
患者被随机分为三组：第1组在内镜检查前未接受苯二氮䓬类药物，全程呼吸室内空气（n = 18）；第2组在内镜检查前静脉注射咪达唑仑，全程呼吸室内空气（n = 20）；第3组在内镜检查期间静脉注射咪达唑仑并通过鼻导管给予2 L/min氧气（第3组；n = 20）。
在七个时间点记录数据，包括心率、心律和SpO2：基线、口咽局部麻醉、插入口咽通气道、插入内镜、活检、取出内镜以及内镜检查后五分钟。在第2组中，给予咪达唑仑后平均SpO2下降，在内镜检查期间仍处于较低水平（p < 0.05）。给予咪达唑仑后，第2组患者与第1组和第3组患者有显著差异（p < 0.05）。
使用催眠剂量的苯二氮䓬类药物是内镜检查期间氧合降低的主要原因。单纯内镜的存在或咪达唑仑与补充氧气的联合使用均未导致氧合降低。本研究还表明，当内镜检查时间较短且内镜医师对口咽进行良好的局部麻醉时，常规使用苯二氮䓬类药物是不必要的。对于需要在内镜检查时进行镇静的患者，给予氧气可预防低氧血症。
