胸腹主动脉瘤手术的麻醉处理

4.炎症反应 慢性炎症反应中的巨噬细胞和活化的T、B淋巴细 胞可刺激金属蛋白酶的产生，促进结缔组织的降解， 削弱和破坏主动脉壁中层，导致产生动脉瘤。
另有研究认为,雌激素水平是动脉瘤的产生
的原因之一:
在腹主动脉瘤形成的过程中雌激素可能
通过降低组织基质金属蛋白酶2、9( MMP-2、
9)的 mRNA 表达、蛋白合成,从而延缓动脉 瘤的形成.
-----国外医学----
二、腹主动脉瘤的病理改变
1.真性动脉瘤：动脉粥样硬化是常见原因。
动脉粥样硬化的危险因素：高胆固醇血症、糖尿病、肥胖、
高血压、吸烟史，男性，等等。
2.假性动脉瘤：多见与动脉损伤。 3.夹层动脉瘤：动脉壁中层囊性坏死或退行 性变。
三、诊断
腹部搏动性包块 神经压迫症状 下肢缺血症状
3.Aoric declamping ★a sudden decrease in afterload with reperfusion of the bowel, pelvis and lower limbs. vasodilatation metabolic acidosis capillary permeability increased blood cells sequestrated in the lungs
术中器官保护
心肌及心脏功能保护 •Decrease myocardial oxygen demand Decrease heart rate Decrease myocardial contractility Decrease LV end-diastolic volume Decrease afterload •Increase myocardial oxygen supply and coronary blood flow Decrease vasoconstriction Decrease thrombosis Increase diastolic time Increase diastolic pressure •Decrease LV end-diastolic pressure Increase oxygen saturation. • Drugs. Mannitol has a positive effect in countering these
华法林4~5天。 2、评估出血风险：目标，术前INR<1.5。
3、Bridging的注意事项：Bridging需在华法林最后一次使用的48h
开始；治疗剂量的低分子肝素（LMWH）应在术前24h停用；栓 塞的高风险患者应在术后48h内启用治疗剂量的LMWH。
Procedures performed before anesthesia:
deleterious pulmonary effects.
神经保护Fra Baidu bibliotek
•缩短主动脉钳夹时间
•局部脊髓低温（32-34oC）
•维持最大限度的高血压状态和术后灌注压
•细胞膜稳定药物、抗缺血-再灌注损伤和减轻全身 炎症反应 •脊髓缺血监测：血糖监测，唤醒，皮层诱发电位
脊髓保护
• 据报道,OAR术后截瘫及轻瘫发生率为 5% ~40%。手术时主动脉阻断时间长短 是影响术后截瘫发生的一个重要因素,主 动脉阻断时间<15 min时截瘫发生率为0; 当>60 min时发生率为25% ~100%。 • ----- Eur JCardiothorac Surg, 2001, 19(2): 203-213.
4.The large heat loss Many patients undergoing this operation are elderly and have a low metabolic rate. All possible measures must be taken to minimize heat loss. (1)Warming of infusion fluids (2)Warming and humidification of anesthetic gases (3)Use a warming blanket (4)Wrapping the bowel in a clear plastic bag (5)The operating theatre
脊髓保护
• 非体外循环下动脉瘤手术是否发生截瘫或肾功 能衰竭，最重要的单一决定因素就是主动脉阻 断时间。20~30min内几乎不发生截瘫。 30~60min为易损期，截瘫的发生率随着阻断 时间的延长由10%上升至90%。 ------------Miller, s Anesthesia edition Ⅵ
Procedures performed before surgery starts: 1.A suitable vein or veins are cannulated with at least one 14-gauge cannula for infusion of warmed fluids. 2.Cannulation of a radial artery. 3.Central venous catheterization for measurement of right atrial pressure. 4.An oesophageal or tympanic membrane temperature probe is inserted for measurement of temperature. 5.The bladder is catheterized for monitoring of urine output.
Key points during anesthesia and operation procedure.
1.Tracheal intubation To maintain systemic arterial pressure stable. (Dopamine or Noradrenalin) The double lumen tubes are necessary for some thoracic approach operations
五、麻醉方法及术中处理
• 全身麻醉、硬膜外麻醉以及联合麻醉等 各种麻醉技术与麻醉药物都已成功应用 于开腹AAA修补术。
• 其中的联合麻醉方式通常是指联合应用 高腰段或下胸段硬膜外麻醉与浅全麻的 复合麻醉方式。
对于术前服用抗凝药物的病例处理
1、药物术前停用：阿司匹林3~7天，波立维（氯吡格雷）5~7天，
胸腹主动脉瘤手术的麻醉处理
中山大学附属第一医院麻醉科 夏杰华
一、腹主动脉瘤病因及发病机制
1.吸烟
烟草燃烧产生的气态物质进入血液，可将
蛋氨酸氧化成蛋氨酸亚砜，蛋白水解酶活性
增加，加重了动脉壁弹力蛋白的降解，引起
动脉壁力量减弱而导致动脉瘤的形成。
2.高血压 与发病率和破裂的危险性有密切的关系 3.年龄因素 动脉壁的弹力蛋白纤维随年龄的增长出现降解、 断裂和钙化，使动脉壁难以承受血压的冲击而发 生动脉瘤。
Vasc-Surg. 2001 Sep-Oct; 35(5): 335-44
平均年龄 68.5 +/-7.7 years. 高血压病史 55%, 心脏病 73.5%, 外周血管疾病 21%, 中风和短时间缺血22%, 糖尿病 7%, 肾功能不全 10%,
吸烟史 80%.
Vasc-Surg. 2001 Sep-Oct; 35(5): 335-44
currently being evaluated as an alternative to open repair.
J-Cardiovasc-Nurs. 2001 Jul; 15(4): 1-14
Newer, minimally invasive catheter-based endovascular technology utilizing stent grafts are currently being evaluated for abdominal aortic aneurysm (AAA) repair.
Organ protection Vascular diseases are associated with these disorders: •Diabetes(糖尿病) •Smoking sequelae(吸烟后发症)
•COPD(慢性阻塞性肺病)
•Hypertension(高血压) •Renal insufficiency(肾功能不全) •Ischaemic heart disease(缺血性心脏病) ……
reoperation for bleeding .
The population-attributable risk for in-hospital mortality was 47% for cardiac arrest and 27% for acute renal failure. Langenbecks-Arch-Surg. 2001 Jul; 386(4): 249-56
脊髓保护
• 脊髓损伤的防治包括:
①缩短脊髓缺血时间: 研究证明主动脉阻断的最安全时 限为30 min;
②脑脊液引流:降低脑脊液压力,提高脊髓灌注压;
③术中低温技术：低温可减少神经组织的需氧量,降低组 织代谢率,稳定细胞膜,增加组织对缺血耐受性,减少兴 奋性递质释放,从而达到间接保护脊髓目的 ④应用保护性药物:包括超氧化物歧化酶、糖皮质激素、 类固醇、镁离子等。
Complications: Complication rates varied widely among hospitals. Complications
independently associated with increased risk of in-hospital death
include cardiac arrest , septicemia , acute myocardial infarction, acute renal failure , surgical complications after a procedure , and
•Collection and storage of patient，s own blood in the weeks preceding surgery. •Prescribe premedication. •A warming blanket is necessary in the anesthetic room. •Mornitoring.
2.Crossclamping of the aorta ★a sudden increase in systemic vascular resistance (afterload): cardiac work increase myocardial ischaemia
★the large bowel and lower limbs suffer variable degrees of hypoxia: inflammatory mediators released oxygen radicals neutrophil proteases platelets activating factor cyclo-oxygenase products cytokines
血管造影、CT、MRI、高速螺旋CT等 影像学检查
四、胸腹主动脉瘤的手术方式及概况
手术方式：
1.Open repair
2.Medal graft stent
3.Baloon-expandable
4.Hand-help laparoscope repair
Elective surgery by open transperitoneal or retroperitoneal approach is the most common repair intervention. However, placing an endoluminal stent graft within the aneurysm is