CLINICAL REASONING TEST #1       Clinical reasoning is the art of constructing the path leading from the symptoms to the diagnosis. The aim of this test is to start with some initial laboratory findings and lead you to the appropriate diagnosis. Cinical reasoning cannot be explained or exercised using the quiz format; have a pen and a notebook with you and write down the answers to the questions; then press . The case here presented aims to be pedagogical rather than realistic: in a real context you will probably have more compex conditions, and more information available, because maodern instruments test many parameters at once (e.g. a modern hemogas analysis most probably includes also the measurment of glycemia and electrolytes). Here we shall start from very little information and build up our path more gradually.       The patient is a young adult, confusional; anamnestic information is not available. He is dispneic with 25 respiratory acts per minute.       A hemogas analysis is prescribed that reveals: PO2 = 90 mmHg PCO2 = 25 mmHg bicarbonate = 8 mM pH = 7.1 anion gap = 26 mEq / L Questions (to be answered on your notepad): 1) Define this condition 2) List its possible causes / diagnoses When done press the [done1] key.