Lab value interpretation sadly wasn't included in my initial paramedic education. I was absolutely ecstatic to attend a critical care program and learn about lab values - I had always found it very impressive when people could interpret lab values. I wanted to be a lab value wizard too! Unfortunately, in critical care class, our lectures and resources were nothing like what I had hoped for.I hope this series of blogs serve as a resource for those who are eager to learn more about the art of interpreting labs. I wouldn't recommend tackling this whole thing in one sitting ;) We'll be starting with the positive charges (cations) in this blog, then handling the other parts of the basic metabolic panel in weeks to come (negative charges, renal, and glucose).       Before we get started, I want to get us in the right headspace for learning about lab values. This stuff is kind of dense, and there are a lot of different conditions that will cause lab values to reach their outer limits, or beyond. While I'll present a lot of information for each lab value abnormality, the theory of what's going on is far more important. Once you understand the theory of why a problem occurs, you can find a formula, calculator, or treatment guideline to get you the rest of the way.       Now let's what happens when cations reach their outer limits!