肾移植后急性呼吸窘迫综合征患者氧代动力学分析

Oxygen kinetics in patients with acute respiratory distress syndrome after kidney transplantation/

目的：研究肾移植后不明原因呼吸系统感染患者的微生物特点及并发急性呼吸窘迫综合征（ＡＲＤＳ）的氧缺陷机制。方法：对并发ＡＲＤＳ的患者除了痰的病原学检查外，进行了氧代动力学、肿瘤坏死因子（ＴＮＦ）及血小板计数（ＢＰＣ）的监测。结果：发现结核杆菌和真菌感染例次较多（５／７）。在ＡＲＤＳ患者中，当氧消耗增加（１３２±５２ｍｌ·ｍｉｎ－１／ｍ２比１９１±５５ｍｌ·ｍｉｎ－１／ｍ２，Ｐ＜０．０５），而氧输送维持正常时，氧摄取率没有相应增加；ＴＮＦ水平显著高于正常（１３０．９±５５．９ｍｇ／Ｌ比＜５．０ｍｇ／Ｌ，Ｐ＜０．００１）。入院第３天的死腔通气率（ＶＤ／ＶＴ）高于第１天（０．３２８±０．１０３比０．１７９±０．０３６，Ｐ＜０．０５），ＢＰＣ正相反〔（７４．０±３２．１）×１０９／Ｌ比（１２９．４±５２．５）×１０９／Ｌ，Ｐ＜０．０５〕。表明肾移植后不明原因呼吸系统感染中，结核杆菌和真菌感染率较高。并发ＡＲＤＳ患者的氧缺陷表现为高氧耗型，并可能与ＴＮＦ介导的系统性炎症反应有关。结论：肺的微循环梗塞导致ＶＤ／ＶＴ增加是肺氧合难以改善的主要原因；对于高氧耗型氧缺陷患者维持正常水平氧供可能是不够的，需达到超正常水平氧输送。

Objective:In order to study microbiologic characters in patients with undetermined pulmonary infection and mechanism underlying oxygen deficit in patients with acute respiratory distress syndrome (ARDS) after kidney transplantation.Methods:In addition to microbiologic examination of sputum,measurements of oxygen kinetics,tumor necrosis factors (TNF) and blood patelet counts (BPC) were performed in those patients complicated by ARDS.Results:It was found that incidence of tuberculosis and fungi infection were high (5/7).In patients with ARDS,while oxygen consumption was increased (132±52 vs. 191±55 ml·min -1 /m 2, P <0 05)and oxygen delivery remained normal range,oxygen extraction ratio was not increased correspondingly,TNF levels were significantly high compared with the normal values ( P <0 001).Dead space ventilation ration ( D/ T) was higher on day three than that on day one after admission (0 328±0 103 vs.0 179±0 036, P <0 05),contrary to the changes in BPC (74 0±32 1)×10 9/L vs.(129 4±52 5)×10 9/L, P <0 05 .Conclusions:It is suggested that there are high incidences of tuberculosis and fungi infection in patients with undetermined pulmonary infection after kidney transplantation.Oxygen deficit in patients with ARDS were manifested by high O 2,which may be related to systemic inflammatory response mediated by TNF.Increased D/ T resulted from pulmonary microcirculatory infraction is a major cause for difficult to improve pulmonary oxygenation in those patients.Thus,maintaining normal oxygen delivery appears to be inadequate to support pulmonary oxygenation in patients with high O 2.