開心術前後の肺構造とリン脂質、特に僧帽弁疾患人工弁置換症例について

Observations on Pulmonary Alveolar Structures and Phospholipids before and after Open Heart Surgery for Prosthetic Mitral Valve Replacement

　筆者らの教室で施行した開心手術534例（昭和43年10月現在）につき，とくに呼吸管理の面から検討し，僧帽弁疾患で開心交連切開および人工弁置換を行なった36例中17例，ファロー四徴症59例中25例に術後経過中気管切開やIPPB等の呼吸補助，さらには肺合併症を認めた。また夫々の死亡数は1および7例で，肺合併症が直接死因となったものは，それらのうちの1および2例でした。すなわち先天性ではチアノーゼ性心疾患を代表するファロー四徴症に，後天性では僧帽弁疾患に術後呼吸管理に留意する必要性を示している。後者ではまた術前，術後の動脈血血液ガス分圧の経過を観察すると，他の心疾患に比較してPaO₂の減少すなわち，hypoxemiaが全経過を通じて持続することも明かになった。今回は僧帽弁疾患患者で人工弁置換手術を施行した症例につき，術前後の肺胞形態とリン脂質の変化を検討したので報告する。

Lungs of patients operated upon for mitral insufficiency were studied morphologically and biochemically to observe the influence of cardiopulmonary bypass. Alterations of the pulmonary structures were noted in the type Ⅱ alveolar epithelial cells and the interstitiumpostoperatively. Dilatations of capillaries and interstitial edema became evident. Con-comitantly decreased number of granules containing lamellar structures, enlargement and fusing of these granules, and invasions of swolled and coarse lamellar structures to a granule forming a bulky conglomeration were notable following surgery in the type Ⅱ alveolar epithelial cells.

Ratio of wet to dry pulmonary tissues was increased pre- and postoperatively in compa-rison with the control (lung tissue derived from patients without cardiopulmonary by-pass), suggesting the presence of a tight lung in this disease. Total pulmonary phos-pholipid was found to be less even before surgical procedure, however, showed a tend-ency to increase postoperatively. No 'marked changes were observed in the fractions of phospholipid.