This is a method for interpreting Arterial Blood Gas (ABGs) values for the medical professional. Some people also refer to ABGs as pH balance. This is a super easy way of learning how to work with ABGs. We will cover some of the basics of pH balance and see how the carbonic acid formula relates to it. The X method has be presented to many of my student and within a short period of time (usually less than one hour) they have become well versed on how to read ABGs.