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Intrapulmonary or intracardiac thrombosis is a rare but catastrophic event following complex cardiothoracic surgery. Although there have been multiple cases reported in the literature, the causes of these events are largely unknown. In this retrospective review, we attempt to identify risk factors and propose possible mechanisms of thromboses after cardiopulmonary bypass (CPB).A literature search was conducted using the MEDLINE and EMBASE with these keywords: (intra)pulmonary thrombosis, pulmonary embolism, pulmonary infarction, lung embolism, (intra)cardiac thrombosis, cardiac thrombi, in combination with CPB, extracorporeal membrane oxygenation, deep hypothermic circulatory arrest, or cardiac surgery. Putative risk factors were compiled from reported cases.We identified 34 cases of massive intrapulmonary and/or intracardiac thromboses. All but 2 cases (94.1%) were fatal. Clinical presentations were systemic hypotension and/or pulmonary hypertension, right ventricular failure, and cardiogenic shock in 32 (94.1%) cases. The timing was immediate (10 min) following hemostatic intervention in 16 cases (47.1%), within 45 min in 8 cases (23.5%), and not reported in the rest. Putative risk factors included antifibrinolytic use (88.2%), congestive heart failure (55.9%), prolonged CPB use (2 h) (41.1%), and low activated clotting time (400 s) after initial heparinization (20.6%). The administration of tissue plasminogen activator in 5 cases was ineffective.Massive thrombosis following cardiac surgery is a highly lethal event with limited treatment options. Particular attention should be paid to the status of thrombin regulatory proteins before protamine and other hemostatic interventions in patients undergoing complex cardiac surgery with antifibrinolytic agents.

Antifibrinolytic agents have been prophylactically administered to patients undergoing cardiopulmonary bypass (CPB) to reduce postoperative bleeding due to plasmin-mediated coagulation disturbances. After the recent market withdrawal of aprotinin, a potent bovine-derived plasmin inhibitor, two lysine analogs, epsilon-aminocaproic acid and tranexamic acid are currently available for clinical use. Although the use of aprotinin recently raised major concerns about postoperative thrombosis and organ dysfunctions, there is a paucity of information on the potential complications related to lysine analogs. Using the available preclinical and clinical data, we present current perspectives on the hemostatic mechanism and potential harms of antifbirnolytic therapy related to cardiac surgery. Fibrin formation is the critical step for hemostasis at the site of vascular injury, and localized fibrinolytic activity counterbalances excess fibrin formation which might result in vascular occlusion. Inhibition of the endogenous fibrinolytic system may be associated with thrombotic complications in susceptible organs. It is thus important to understand CPB-related changes in endogenous fibrinolytic proteins (e.g., tissue plasminogen activator (tPA), plasminogen) and antifibrinolytic proteins (e.g., alpha(2)-antiplasmin).

Apicoaortic bypass (AAB), or apicoaortic conduit insertion, is a conventional surgical method that has been regaining attention due to the aging population and the increasing number of repeat surgeries. The indication for the procedure has been extended as an alternative for aortic stenosis when the usual sternotomy or aortic clamping is considered to be difficult, e.g., in patients with severe calcification of the ascending aorta (porcelain aorta), or in patients with a patent coronary artery bypass graft located adjacent to the posterior surface of the sternum. Herein, we report our recent anesthetic management of three patients undergoing AAB. Once the apicoaortic conduit is inserted, blood from the left ventricle is ejected via two routes, the narrowed native aortic valve and the apicoaortic conduit. Thus, it is necessary to elucidate any change in blood flow after the withdrawal of the extracorporeal circulation, by using intraoperative transesophageal echocardiography. Furthermore, if a rigid apical connector is not used, anastomosis of the cardiac apex and conduit is conducted under ventricular fibrillation without the infusion of cardioplegic solution; thus, patients are deemed likely to suffer increased myocardial damage. As a rigid apical connector was not used in the three present patients, the administraction of adequate catecholamines was needed for the withdrawal of the extracorporeal circulation. In addition, because those undergoing AAB often have extremely poor cardiac reserve preoperatively owing to the administration of adequate catecholamines was needed for the withdrawal of the extracorporeal circulation. In the three present patients, anesthetic management was successful, and there were no intraoperative or immediate postoperative complications.

非体外循環下冠動脈バイパス術(off-pump coronary-artery bypass grafting, off-pump CABG)術後に原因不明の強い全身性炎症を示し多臓器障害を呈したが,大量のコルチコステロイド投与により劇的に改善した症例を経験したので報告する。症例は72歳男性,既往症は高血圧,59歳時にCABG,70歳時に腹部大動脈瘤に対して人工血管置換術を受けた。今回増悪する狭心症に対してoff-pump CABGを受けたが,術後3日目より高熱,白血球増多,CRP高値を呈し,ショック,腎不全,高ビリルビン血症を合併した。アレルギー性疾患,感染症は否定的であった。術後12日目に,炎症の治療目的で,メチルプレドニゾロン500mgを3日間投与したところ,発熱,高炎症,多臓器障害は速やかに改善した。メチルプレドニゾロンの投与期間は25日間,その後,術後42日目に無事転棟となった。敗血症,ARDSなどの重症患者に対する高用量ステロイド投与による予後改善は現在否定されているが,今回のように全身性炎症状態のみが病態をなしている場合には有効でありうると考えた。

Purpose. The study was done to determine the characteristics and prevalence of myocardial ischemia with inverted T waves after noncardiac surgery. Methods. A list of patients who developed electrocardiogram (ECG) T-wave inversion associated with wall-motion abnormalities observed by transthoracic echocardiography (TTE) following noncardiac surgery was generated from the intensive care unit (ICU) medical records database between January 1, 1995, and December 31, 2000. The hospital records of these patients were analyzed retrospectively. Results. Among 4219 patients (2187 men and 2032 women) who were admitted to the ICU after noncardiac surgery, 13 developed myocardial ischemia with inverted T waves postoperatively. All of the patients were middle-aged or elderly women with no history of coronary artery disease; nine of them had undergone intraabdominal surgery. Characteristic ECG findings included inverted T waves in the left precordial leads, which subsequently became prominent with QT prolongation. In all of these patients, wall-motion abnormalities were observed on the anterior wall, but these resolved within 60 days of the episode. Myocardial ischemia was asymptomatic, with neither hemodynamic changes nor adverse cardiac events. Conclusion. Newly developed giant negative T waves with QT prolongation in the ECG may indicate myocardial stunning, but do not in themselves imply a poor prognosis. The marked preponderance of middle-aged and elderly women with this type of myocardial ischemia remains to be explained.

パラチオンを服毒した慢性透析患者において,持続的血液透析(continuous venovenous hemodialysis,CVVHD)下におけるpralidoxime(2-PAM)薬物動態を検討しえた。症例は67歳の男性で,週3回の血液透析を受けていた。自殺企図にてパラチオン15mlを服毒し,アトロピン,2-PAMを併用した心肺蘇生に成功の後,ICUに収容した。筋攣縮や縮瞳などの症状の改善を目安にCVVHD施行下で2-PAM0.1g・hr-1を約20時間持続投与し,血中ならびに透析廃液中の2-PAM濃度を経時的に測定してCVVHDによる排泄と薬物動態を検討した。その結果,持続投与中の血中濃度は22～23mg・ml-1と高値であり,CVVHDによるクリアランスは約8.1ml・min-1と極めて小さく,半減期が健常人の1.1時間に比べ40時間と著明に延長することが判明した。有機リン中毒に対しCVVHD施行下で2-PAMを投与する場合,体外排泄の遅延による過剰投与に十分注意する必要があると考えられた。

Transesophageal echocardiography is an invaluable hemodynamic monitoring modality. Extended and anatomically based evaluation of cardiac function with transesophageal echocardiography is essential to prompt and accurate decision-making in anesthetic management during cardiac surgery. Fractional shortening and fractional area changes are indices widely used to assess the global systolic performance of the left ventricle. Monitoring regional function using semi-quantitative scoring has been demonstrated to be a more sensitive indicator of myocardial ischemia. Assessment of left ventricular diastolic function should be performed in a systematic way, measuring transmitral flow, pulmonary venous flow, transmitral color M-mode flow propagation velocity, and mitral annulus tissue Doppler imaging. The unique anatomical features of the right ventricle make echocardiographic evaluation complicated and therefore less frequently employed. Right ventricular fractional area change, tricuspid annular plane systolic excursion, maximal systolic tricuspid annular velocity with tissue Doppler imaging, and myocardial performance index are indices successfully incorporated into intraoperative right ventricular assessment. Left ventricular outflow tract obstruction with systolic anterior motion of the mitral valve may develop after cardiac procedures. Transesophageal echocardiography plays a central role in prevention as well as diagnosis of systolic anterior motion. Transesophageal echocardiography is extremely useful not only for detecting and locating intracardiac air, but also for guiding and evaluating the procedures to remove air. Air is likely to persist in the right and left superior pulmonary vein, left ventricular apex, left atrium, right coronary sinus of Valsalva, and ascending aorta. Accurate evaluation of cardiac function depends on performing TEE examination properly and obtaining optimal images.