The pathology of pulmonary embolism changes _'s general knowledge

The pathology of pulmonary embolism changes _'s general knowledge
Pathologic change
Most acute pulmonary embolism can be involved manily and propped up the lung artery, the position of thromboembolism is a right lung, more than the left lung, leaf at lower leaf exceed, but thromboembolism ride in the intersection of lung and the intersection of artery and the intersection of branching and in Right deviation or left the intersection of lung and the intersection of artery and backbone rarely. Thrombus the intersection of embolus and plane, when the difference, through heart being apt to form the intersection of chip and thromboembolism in low blood vessel in the route. If fine dissolves the mechanism and can't totally dissolve the thrombus, the surface of embolus is covered for one kind of cells of inner skin gradually 24 hours later, 2- stick in the artery wall firmly 3 weeks later, the blood vessel is rebuilt. Early embolus shrink back, the intersection of blood flow and coherent souring, cover on the intersection of embolus and cellulose, agglutinate thing of blood platelet of surface and dissolve the bolt course, can all produce the small blood vessel branch of further thromboembolism of the new embolus. Embolus cause lung block up, give much trouble the intersection of blood vessel and size, block range, bronchus artery supply ability and getting obstructive to keep in touch with appropriate decision or not of blood flow. The histologic characteristic that the lung blocks up is alveolus internal haemorrhage and alveolus wall necrosis, but seldom find inflammation, when there was not lung infecting or embolus originally that is non-infective, seldom produce the cavity. Person who block up the intersection of lung and the intersection of surface and active substance lose, can cause the intersection of lung and piece, pleura surface oozed out commonly, 1/3 are the courage and uprightness. If can survive, form cicatrix finally in the blocking up area.
Cause the increase of physiological dead space after pulmonary embolism, keep in touch with efficiency to reduce, but can be stimulated and kept in touch with because of acute pulmonary embolism, increase the respiratory rate and keeping in touch with amount of every minute, usually offset the increase of the physiological dead space, keep PaCO2: Do not rise even reduce. The alveolus is excessively kept in touch with and had nothing to do with hypoxemia disease, even can't be dispelled by oxygen intake. Its mechanism is not so obvious, infer that relates to reflection of the regional lung essence of vascular thromboembolism. Though PaCO2 usually reduces, neural muscle illness, the pleura pains vigorously and the serious patient of pulmonary embolism can't increase correspondingly and keep in touch with while compensating the increased physiological dead space, can present CO2 retention. It is acute when pulmonary embolism is common PaO2 reduce,it keep in touch with /lack proper care to be may their mechanisms mains blood flow ratio, some bronchus shrink, lung piece and lung edema dissect foundation for it. If the cardiac output can't need to keep unanimity with the supersession, mixing the partial pressure of oxygen of intravenous blood will reduce, can aggravate keep in touch with lack proper care by blood flow ratio and hypoxemia disease further.
The machinery of pulmonary embolism acts on directly and is more complicated that chemical blood dynamics that causes with the diastaltic mechanism reacts after thromboembolism. Thromboembolism of less with with little embolus number does not cause blood dynamics of lung to change. Say lung the intersection of blood vessel and bed block> 30% hour, the average lung arterial pressure begins to rise generally> 35% o'clock the right room is pigeonholed and risen, the lung blood vessel bed is lost> 50% o'clock, can cause the lung arterial pressure, lung blood vessel resistance to increase notably, the heart index reduces and acute lung worry. Repeated pulmonary embolism produced artery high pressure and chronic lung worry of permanent lung. Damaged patient in the original heart and lungs function, blood dynamics of pulmonary embolism influences more usually the patient is far is outstanding.
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