Heres E K, Marquez J, Malkowski M J, Magovern J A, Gravlee G P
Department of Anesthesiology, Allegheny General Hospital, Allegheny University of the Health Sciences, Pittsburgh, PA 15212, USA.
J Cardiothorac Vasc Anesth. 1998 Aug;12(4):385-9. doi: 10.1016/s1053-0770(98)90188-4.
Minimally invasive direct coronary artery bypass (MIDCAB) provides many anesthetic challenges including monitoring, managing myocardial ischemia, and pain control. The objective was to evaluate the monitoring requirements and the potential benefits of preischemic conditioning and intrathecal morphine sulfate in MIDCAB patients.
This review was retrospective and unrandomized and was conducted at Allegheny University Hospitals, Allegheny General, Pittsburgh, PA.
Sixty-four patients with single coronary artery lesions (> 70% obstruction) underwent attempted MIDCAB during a 1-year period between November 1995 and November 1996. Seven patients required conversion to conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) and two patients required extended thoracotomy incisions. This report describes the remaining 55 patients who underwent MIDCAB.
Some of the MIDCAB patients received intrathecal morphine before anesthetic induction. Ischemic preconditioning was assessed in a subset of patients.
MIDCAB was performed in 55 of 64 patients. Transesophageal echocardiography (TEE) was used in all patients and a pulmonary artery catheter was used in 43% of patients. Esmolol was used in 25% of patients to reduce motion of the left ventricle (LV) during the left internal mammary artery (LIMA)-LAD anastomosis, but was used less often as the surgeons adapted to the use of a retractor that stabilized the ventricular wall adjacent to the site of the LIMA-LAD anastomosis. LAD occlusion caused reversible, regional systolic dysfunction by TEE in the anterior and apical LV segments. During LAD occlusion, nitroglycerin was used in 61% of patients and phenylephrine in 24%. Ischemic preconditioning did not prevent increases in systemic or pulmonary artery pressures during LAD occlusion. Most (85%) patients were extubated in the operating room. Intrathecal morphine decreased postoperative analgesic requirements. The mean hospital length of stay (LOS) was 4.0 +/- 1.7 days (range, 1 to 10 days).
MIDCAB may reduce hospital LOS for patients with single vessel coronary artery lesions when compared with median sternotomy with a LIMA-LAD graft performed on cardiopulmonary bypass. Pharmacologic heart rate control during the LIMA-LAD anastomosis is not critical with the use of a surgical retractor which diminishes ventricular motion. A single 5-minute test LAD occlusion did not protect against subsequent regional ischemic dysfunction in our subset of patients with normal baseline function.
微创直接冠状动脉旁路移植术（MIDCAB）带来了诸多麻醉挑战，包括监测、处理心肌缺血及控制疼痛。目的是评估MIDCAB患者的监测需求以及缺血预处理和鞘内注射硫酸吗啡的潜在益处。
本综述为回顾性且非随机的，在宾夕法尼亚州匹兹堡阿勒格尼综合医院阿勒格尼大学医院进行。
64例单支冠状动脉病变（阻塞>70%）患者在1995年11月至1996年11月的1年期间接受了MIDCAB尝试。7例患者需要转为体外循环（CPB）下的传统冠状动脉旁路移植术（CABG），2例患者需要延长胸廓切开切口。本报告描述了其余55例行MIDCAB的患者。
部分MIDCAB患者在麻醉诱导前接受鞘内吗啡注射。在部分患者中评估了缺血预处理。
64例患者中有55例进行了MIDCAB。所有患者均使用经食管超声心动图（TEE），43%的患者使用了肺动脉导管。25%的患者使用艾司洛尔以减少左乳内动脉（LIMA）-左前降支（LAD）吻合期间左心室（LV）的活动，但随着外科医生适应使用稳定LIMA-LAD吻合部位相邻心室壁的牵开器，其使用频率降低。LAD闭塞通过TEE导致LV前壁和心尖段出现可逆性局部收缩功能障碍。在LAD闭塞期间，61%的患者使用硝酸甘油，24%的患者使用去氧肾上腺素。缺血预处理未能防止LAD闭塞期间全身或肺动脉压力升高。大多数（85%）患者在手术室拔管。鞘内吗啡减少了术后镇痛需求。平均住院时间（LOS）为4.0±1.7天（范围1至10天）。
与在体外循环下进行LIMA-LAD移植的正中胸骨切开术相比，MIDCAB可能会缩短单支冠状动脉病变患者的住院时间。使用减少心室活动的手术牵开器时，LIMA-LAD吻合期间的药物心率控制并不关键。在我们基线功能正常的患者亚组中，单次5分钟的试验性LAD闭塞并不能预防随后的局部缺血性功能障碍。
