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The acute and chronic dyspnea mind map is organized based upon pathologies arising from cardiac, pulmonary and extra cardio-pulmonary systems. The reason for this organization is that pathologies arising from these systems often give rise to similar constellation of symptoms and signs. For example, dyspnea from COPD, interstitial lung disease and lung mass may be accompanied by a cough. Dyspnea from fluid overload conditions, such as congestive heart failure, renal failure and hepatic failure may be accompanied by lower extremity edema, and abdominal swelling, etc. The list of probable diagnoses can be memorized in the form of chunks based upon these systems.

            Most causes of dyspnea can potentially lead to an urgent or emergent situation. A few exceptions include chronic obesity-hypoventilation syndrome and psychogenic dyspnea, which are not listed on this mind map. Most cases of acute dyspnea should be considered as urgent or emergent situations unless proven otherwise. Addressing urgent and emergent situations involves reviewing the patient’s appearance of distress, presence of anaphylaxis, stridor, foreign body, trauma and obvious signs of extreme fluid overload or decreased perfusion. These are reflected in abnormal vital signs, such as tachypnea, tachycardia, low oxygen saturation, and altered mental status.

            Weighing and removing anchor bias involves first asking high yield questions (such as duration) and then medium yield questions, which represent constellation of symptoms associated with a particular system or organ. Chest pain, orthopnea and paroxysmal nocturnal dyspnea point to cardiovascular etiology, whereas cough, wheezing and phlegm point to a pulmonary etiology, and fatigue or any signs of blood loss point to anemia.  Patients with a chronic condition may present with an acute episode of dyspnea. Some examples are chronic bronchitis, and congestive heart failure. In such cases, when asked about the onset of symptoms, patients may state that their dyspnea started a few days or even a few hours ago. This may lead a clinician to suspect that an acute etiology is at play and overlook chronic conditions. In order to not miss any chronic diagnoses, a clinician must ask questions about the onset of symptoms, previous episodes, baseline symptoms, and past medical history. Asking questions about the constellation of symptoms belonging to specific systems helps further narrow differential diagnoses, and a physical exam and lab findings help confirm the final diagnosis. A common question asked about shortness of breath is whether or not the breath shortness is related to exertion. However, this information does not provide much help in terms of diagnostic reasoning because in most cases, regardless of the underlying etiology, the symptoms of dyspnea worsen with exertion. 

Various physical exam findings, which have been described in textbooks, are highly specific, but not very sensitive and/or occur at the end stage of the diseases processes. Therefore, most patients may not manifest these symptoms. Examples are “blue bloaters” for chronic bronchitis and “pink puffers” appearances for emphysema. The absence of such findings should not lead to ruling out relevant diagnoses. Labs and appropriate tests can help establish the final diagnosis.