Which of the following method is used to determine acid base composition of blood based on PC02?
High-Yield Explanation
Siggard Anderson normogram helps to assess acid base conditions, base excess values, effective degree of hypoventilation or hyperventilation. In this normogram PCO2 is plotted on Y axis and pH on X axis. On the normogram, any point to the left of a veical line through pH 7.40 indicates acidosis, and any point to the right indicates alkalosis. The position of the point above or below the horizontal line through a PCO2 of 40 mm Hg defines the effective degree of hypoventilation or hyperventilation. The point at which the CO2 calibration line intersects the lower curved scale on the nomogram indicates the base excess. This value, which is positive in alkalosis, it refers to the amount of acid or base required to restore 1 L of blood to normal acid-base composition at a PCO2 of 40 mm Hg. Ref: Review of Medical Physiology, Ganong 23rd Edition, Chapter 40 ; Bijlani 3rd Edition, Page 451 ; Dr Podcast Scripts for the Primary FRCA By Rebecca A Leslie, Page 97.