BLOOD BUFFERS: a program to simulate blood pH The model here presented has three parameters: arterial pH, arterial PCO2 and the overall buffer capacity of arterial blood. It calculates the changes in pH and buffer capacity induced by respiratory changes in PCO2; for example, if an estimate of the venous PCO2 is provided, it calculates the arterio-venous pH difference and total CO2 difference. If an altered PCO2 is provided the program calculates the blood parameters under the assumption of constant sum opf deprotonated buffer components (Sdp=[HCO3-]+[B]) and constant hidden buffer concentration ([B]+[HB+]): this feature can be used to simulate acute respiratory acidosis or alkalosis. A detailed explanation of the model is provided below. arterial blood pH (normal value: 7.4) arterial PCO2 (in mmHg; normal value: 38) overall buffer capacity (normal value: 35-38 mEq/L), if known hemoglobin concentration (g/dL; normal value 14; necessary if overall buffer capacity is not known) venous PCO2 (in mmHg; normal value: 45) acutely altered arterial PCO2 (standard: 40 mmHg; acute resp. acidosis: 70; etc.) Should I explain the model? no yes