课件：全麻并发症.ppt

全身麻醉期间严重并发症的防治 呼吸道梗阻 respiratory obstruction 呼吸道梗阻:上梗(upper airway obstruction) 下梗 (lower airway obstruction) 或 完全性梗阻(completely obstruction) 部 分 性梗 阻(partially obstruction) 临床表现: 胸部和腹部呼吸运动反常，吸气性喘 鸣，呼吸音低或无,三凹征、呼吸困难， 呼吸动作剧烈，但无通气或通气量低。 舌后坠（上梗） (Tongue falling afterward ) 镇静、镇痛药、全麻药及肌松药→下颌骨及舌肌 松驰→舌坠向咽部阻塞上呼吸道 不完全性:鼾声(Snore) 舌后坠阻塞咽部(pharynx) 完全性:只有呼吸动作, 无呼吸交换,SpO2↓ Reduced muscle tone with apposition of the tongue and pharyngeal soft tissue is a common cause. This is usually overcome by jaw lift and use of an oral or nasopharygeal airway. The patients should be placed in a head-down position. 二、分泌物、脓痰、血液、异物阻塞气道 ▲对气道有刺激性的麻醉药→分泌物↑（术前 给足量抗胆碱药） ▲支扩、湿肺等→大量脓痰、血液堵塞气道（双腔插管，术中吸引） ▲鼻咽、口腔等手术→积血、敷料阻塞（气管插管） ▲脱落的牙或义齿阻塞气道（麻醉前拔除或取出） 反流与误吸 (Regurgitation and aspiration) 原因（Aetiology）: Regurgitation and pulmonary aspiration of gastric contents are more likely to occur in patients with intra-abdominal pathology,delayed gastric emptying or inadequate gastro-oesophageal sphincter function. Aspiration is more common during emergency ,obese or obstetric patients. Mortality is high after major aspiration. 应用吗啡类、全麻药、肌松药后→贲门括约肌松驰→胃内容物反流→下呼吸道严重阻塞→误吸死亡率50%～75%。 误吸胃液→突发支气管痉挛、呼吸急速、困难、肺内弥漫性湿罗音，严重缺O2. Bronchospasm is the first sign . If a large quantity of gastric material is aspirated, respiratory obstruction, V/Q mismatch and intrapulmolary shunting may produce severe hypoxaemia,with chemical pneumonitis. 预防（prevention)： ◆择期手术术前:＜6月： 4h禁奶及固体食物，2h禁清亮液体. 6～36月：6h禁奶及固体食物，3h禁清亮液体. ＞36月： 8h禁奶及固体食物，3h禁清亮液体. ◆备吸引器、鼻胃管减压. ◆饱胃、高位肠梗阻：宜清醒气管插管(awake intubation). ◆H2-R拮抗剂(to reduce the acidity of gastric contents). 处理(management): 发生反流误吸时→头低位(head-down position)、转向一侧、吸引 (suction)、支气管解痉药（bronchodilator)、必要时