特集名 | 透析と呼吸器 | |
---|---|---|
題名 | 透析における呼吸器合併症 (4) 肺水腫 | |
発刊年月 | 1997年 12月 | |
著者 | 原田 敬 | 長崎大学医学部附属病院第二内科, 北九州八幡病院循環器科 |
【 要旨 】 | 肺毛細血管内圧上昇や透過性亢進等により血管から肺間質への水分移動は増大する.これがリンパ等の除去能力を上回ったときから,移動と除去の均衡が崩れて肺水腫となる. 慢性腎不全のおける肺水腫は,大半が水・Na負荷による血管内圧の上昇で発生し,適切な除水により肺間質水分は減少するであろう. 一方で慢性腎不全には,貧血・高血圧・内シャント等による心負荷,priming volime の影響や透析膜による活性化好中球の肺毛細血管への集積など,肺水分量を増加させる多くの因子が予想される. われわれは,熱Na二重指示薬希釈法を用いて,慢性腎不全患者における透析中の肺水分量を検討した.透析前の肺水分量は,ほとんどの症例で高値を示し,透析終了時には有意に減少した.ところが約半数の症例で,透析中に肺水分量が一過性に増加した.この現象は,血管内圧の変化以外の因子が関与していることを示唆するものかもしれない. |
Theme | Dialysis Therapy and Respiratory Systems | |
---|---|---|
Title | Pulmonary edema | |
Author | Takashi Harada | Second Department of Internal Medecine, Nagasaki University School of Medecine/ Division of Cardiology, Kitakyusyu City Yahata Hospital |
[ Summary ] | Water flux from pulmonary capillaries to pulmonary interstitial tissue increases in some specific conditions including increased capillary pressure and the increased capillary permeability. When this influx rate is greater than the water removal capacity of the lymph system or other systems, the net water influx into interstitial tissue causes pulmonary edema. In chronic renal failure patients, the primary factor causing pulmonary edema is increased intravascular pressure due to the increased water and/or sodium load. Effective ultrafiltration might contribute to the decreased water content within pulmonary interstitial tissue. However, there are also many other factors that contribute to the increased extravascular lung water in patients with chronic renal failure, including the increased cardiac load due to anemia, hypertension, internal shunt, priming volume, etc. ; and accumulation of dialysis membrane activated neutrophils in pulmonary capillaries. These factors may significantly affect the complex response of lung water to hemodialysis treatment. We evaluated the change in extravascular lung water (EVLW) during hemodialysis in patients with chronic renal failure using the heat-sodium double indicator dilution method. In most cases, the EVLW before dialysis showed a higher level which decreased significantly after dialysis. In approximately half of the case, however, the EVLW increased transiently during dialysis. This phenomenon suggests that, in addition to the increased intravascular pressure, there may be other factors contributing to the development of pulmonary edema. |