危重病患者并发低氧血症和酸碱平衡紊乱及预后分析

目的了解危重病患者低氧血症和酸碱平衡紊乱的发生发展规律，探讨其发生机制，分析低氧血症和酸碱平衡紊乱对危重病患者预后的价值，提高对危重病患者低氧血症和酸碱平衡紊乱的认识。方法选择我院2000年1月至2008年12月住院救治的危重病患者368例为研究对象，以同期内科住院患者359例作为对照，所有危重病患者和对照组，用同样的方法测定动脉血气数值：pH、PaCO2、PCO2、HCO3-、TCO2、BE和SaO2；同时测定血生化参数：血清钾、钠、氯、肝功能、肾功能及血糖；低氧血症依据PaO2浓度作出诊断，计算阴离子隙（AG）和潜在HCO3-，依据酸碱失衡预计代偿公式（PCF），做出酸碱失衡的判断。结果危重组368例患者中，发生低氧血症者175例，占47．6％，死亡者79例，占45．1％，其中PaO2≤40mmHg（5．3kPa）者死亡34例，占69．4％；对照组359例患者中，发生低氧血症者76例，占21．2％，死亡者17例，占22．4％，其中PaO2≤40mmHg（5．3kPa）者死亡7例，占36．8％，危重组和对照组低氧血症的发生率和病死率比较，均有非常显著性差异（P〈0．001）。危重组368例患者中，发生不同类型的酸碱失衡共315例，占85．6％，其中死亡者220例，占69．8％；对照组359例患者中，发生单纯性和二重性酸碱平衡紊乱共128例，占35．6％，其中死亡者26例，占20．3％，危重组和对照组酸碱失衡的发生率和病死率比较，均有非常显著性差异（P〈0．001）。结论危重病患者不但低氧血症和酸碱失衡的发生率较高，病死率亦非常高，而且与预后有关，因此，应重视危重病患者低氧血症与酸碱平衡紊乱的预防和及时救治具有重要的临床意义。

Hypoxemia and acid-base disturbance in critically ill patients and prognostic analysis

Objective To understand the rules of the occurrence and development for hypoxemia and acid-base disturbance in critically ill patients, explore their occurrence mechanism, analyze the prognostic value of hypoxemia and acid-base disturbance for critically ill patients, and improve the cognition of hy- poxemia and acid-base disturbance in critically ill patients. Methods 368 critically ill patients hospitalized in our hospital from January 2000 to December 2008 were selected as research objects, and 359 inpatients in internal medicine department during this period were selected as controls. As for all the critically ill patients and controls, arterial blood gas values were measured by the same methods, including pH, PaCO2 , PCO2, HCO3 - , TCO2, BE and SaO2 ; while the blood biochemical parameters were measured, including serum po- tassium, sodium, chloride, liver function, renal function and blood glucose. Hypoxemia was diagnosed based on the value of PaO2. Based on the preestimated compensatory formulas（PCF） of acid-base disturb- anee, acid-base disturbance was diagnosed by calculating anion gap（AG） and potential HCO3 . Reslllts Among 368 critically ill patients, there were 175 cases with hypoxemia and 79 cases of them were died which accounted for 45.1%, including 34 cases with PaO2≤40 mm Hg（5.3 kPa） were died and accounted for 69.4% ; among 359 controls, there were 76 cases with hypoxemia which accounted for 21.2% and 17 cases of them were died which accounted for 22.4% , including 7 cases with PaO2 ~〈40 mm Hg（5.3 kPa） were died and accounted for 36.8%. To compare the incidence and mortality of hypoxemia between the critically ill patients group and the control group, the differences were significant（ P 〈 0. 001 ）. Among 368 critically ill patients, acid-base disturbance with different types occurred to 315 cases which accounted for 85.6% and 220 cases of them were died which accounted for 69.8% ; among 359 cases in control group, simple and double acid-base disturbance occurred to 128