摘要：
Objective To establish the standardization process of acid-base balance analysis, analyze cases of acid-base balance disorder with the aid of acid-base balance coordinate graph.Methods The acid-base balance theory were reviewed systematically on recent research progress, and the important concepts, definitions, formulas, parameters, regularity and inference in the analysis of acid-base balance were studied. The analysis of acid-base balance disordered processes and steps were figured. The application of acid-base balance coordinate graph in the cases was introduced.Results The method of "four parameters-four steps" analysis was put forward to analyze the acid-base balance disorders completely. "Four parameters" included pH, arterial partial pressure of carbon dioxide (PaCO2), HCO3- and anion gap (AG). "Four steps" were outlined by following aspects: ① according to the pH, PaCO2 and HCO3-, the primary or main types of acid-base balance disorder was determined; ② primary or main types of acid-base disorder were used to choose the appropriate compensation formula and to determine the presence of double mixed acid-base balance disorder; ③ the primary acid-base balance disorders were divided into two parts: respiratory acidosis or respiratory alkalosis, at the same time, the potential HCO3- should be calculated, the measured HCO3- should be replaced with potential HCO3-, to determine whether there were three mixed acid-base disorders; ④ based on the above analysis the data judged as the simple AG increased-metabolic acidosis was needed to be further analyzed. The ratio of ΔAG↑/ΔHCO3-↓ was also needed to be calculated, to determine whether there was normal AG metabolic acidosis or metabolic alkalosis. In the clinical practice, PaCO2 (as the abscissa) and HCO3- (as the ordinate) were used to establish a rectangular coordinate system, through origin (0, 0) and coordinate point (40, 24) could be a straight line, and all points on the straight line pH were equal to 7.40. The acid-base balance coordinate graph could be divided into seven areas by three straight lines [namely pH = 7.40 isoline, PaCO2 = 40 mmHg (1 mmHg = 0.133 kPa) line and HCO3- = 24 mmol/L line]: main respiratory alkalosis area, main metabolic alkalosis area, respiratory+ metabolic alkalosis area, main respiratory acidosis area, main metabolic acidosis area, respiratory+ metabolic acidosis area and normal area. It was easier to determine the type of acid-base balance disorders by identifying the location of the (PaCO2, HCO3-) or (PaCO2, potential HCO3-) point on the acid-base balance coordinate graph.Conclusions "Four parameters-four steps" method is systematic and comprehensive. At the same time, by using the acid-base balance coordinate graph, it is simpler to estimate the types of acid-base balance disorders. It is worthy of popularizing and generalizing.%目的 建立酸碱平衡紊乱分析的标准化流程,借助酸碱平衡坐标图对酸碱平衡紊乱案例进行分析.方法 系统回顾酸碱平衡理论和新近研究进展,明确酸碱平衡分析中重要的概念、定义、公式、各种参数的意义及酸碱平衡分析中的规律与推论,梳理酸碱平衡紊乱分析流程和步骤,介绍酸碱平衡坐标图在实例中的应用.结果 总结并提出酸碱平衡紊乱分析的"四参四步"程序化分析方法,以全面分析酸碱平衡紊乱问题."四参"即pH、动脉血二氧化碳分压(PaCO2)、碳酸氢根(HCO3-)和阴离子隙(AG)."四步"即:① 根据pH定酸、碱,然后结合PaCO2和HCO3-两参数,确定原发性或主要酸碱平衡紊乱类型;② 根据原发性或主要酸碱平衡紊乱类型选用合适代偿公式,确定有无双重混合型酸碱平衡紊乱;③ 原发性酸碱平衡紊乱为呼吸性酸中毒(呼酸)或呼吸性碱中毒(呼碱),同时伴有AG增高型代谢性酸中毒(代酸),应计算潜在HCO3-,用潜在HCO3-替代实测HCO3-与经代偿公式计算所得的代偿区间进行比较,进而判断有无三重混合型酸碱平衡紊乱类型;④ 对经前3步判断为单纯代酸(AG增高型)的数据进一步分析,计算ΔAG↑/ΔHCO3-↓比值,判断是否同时合并非AG增高型代酸或代谢性碱中毒(代碱).在临床实际应用中可以借助酸碱平衡坐标图实现对酸碱平衡紊乱类型的快速判断,分别以PaCO2、HCO3-为横、纵坐标建立直角坐标系,经原点(0,0)和(40,24)点可做一条直线,线上所有点pH均等于7.40;以pH=7.40等值线、PaCO2=40 mmHg线(1 mmHg=0.133 kPa)和HCO3-=24 mmol/L线可将图形分成7个区域,分别代表酸碱正常区及主呼碱区、代碱+呼碱区、主代碱区、主呼酸区、呼酸+代酸区、主代酸区,根据患者指标数值,通过读取(PaCO2,HCO3-)或(PaCO2,潜在HCO3-)点在酸碱平衡坐标图上的位置,便可快速判断其酸碱平衡情况及酸碱平衡紊乱类型.结论 "四参四步"程序化分析方法在酸碱平衡紊乱分析中系统且全面,同时借助酸碱平衡坐标图可以对酸碱平衡紊乱的类型进行快速判断,值得普及和推广.
