The rapid interpretation of ABGs need not be the ominous task that it is for so many. Herein, clinicians will learn to interpret ABGs rapidly by answering three simple questions. Is the pH normal, acidotic or alkalotic? Is the pH correctly predicted by the PaCO2? If the pH is abnormal, is the abnormality caused, compensated, or exacerbated by the PaCO2? By answering these simple questions we have all the information we need for an accurate interpretation-weather the ABG is normal, respiratory or metabolic acidosis or alkalosis, or both, acute, compensated or partially compensated. The second section covers the fundamentals of BiPAP and mechanical ventilation management. These guidelines are presented so as to be employed in real-time by physicians and respiratory therapists, or to be converted into policies and procedures.