Answer: Thanks for the question. The intent of the medical directive was for a patient who has an acute exacerbation of pulmonary edema which is the etiology of their shortness of breath or respiratory distress prompting the 911 response. In other words, many patients as you nicely outline have underlying congestive heart failure with poor left ventricular function. It is most likely these patients have some underlying mild pulmonary edema daily for which their primary care physician has prescribed them a host of medications (such as Lasix or an Ace Inhibitor etc.). These patients however are generally well controlled until they have an acute worsening of their pulmonary edema which is manifested by respiratory distress. This can occur suddenly, or over the course of days. The causes for these acute exacerbations can by multiple (new onset atrial fib with loss of atrial “kick”, cardiac ischemia, acute MI, increased fluid intake, medication non-compliance, etc.). Therefore, yes patients can have longstanding pre-existing pulmonary edema, but the medical directive is designed for a patient who is acutely short of breath or in respiratory distress and the underlying cause of this is judged by the paramedic to be related to pulmonary edema. The patient you describe above fits this category and therefore should be treated as you describe. We hope this helps to clarify!