Acute dyspnea in the office.

Respiratory difficulty is a common presenting complaint in the outpatient primary care setting. Because patients may first seek care by calling their physician's office, telephone triage plays a role in the early management of dyspnea. Once the patient is in the office, the initial goal of assessment is to determine the severity of the dyspnea with respect to the need for oxygenation and intubation. Unstable patients typically present with abnormal vital signs, altered mental status, hypoxia, or unstable arrhythmia, and require supplemental oxygen, intravenous access and, possibly, intubation. Subsequent management depends on the differential diagnosis established by a proper history, physical examination, and ancillary studies. Dyspnea is most commonly caused by respiratory and cardiac disorders. Other causes may be upper airway obstruction, metabolic acidosis, a psychogenic disorder, or a neuromuscular condition. Differential diagnoses in children include bronchiolitis, croup, epiglottitis, and foreign body aspiration. Pertinent history findings include cough, sore throat, chest pain, edema, and orthopnea. The physical examination should focus on vital signs and the heart, lungs, neck, and lower extremities. Significant physical signs are fever, rales, wheezing, cyanosis, stridor, or absent breath sounds. Diagnostic work-up includes pulse oximetry, complete blood count, electrocardiography, and chest radiography. If the patient is admitted to the emergency department or hospital, blood gases, ventilation-perfusion scan, D-dimer tests, and spiral computed tomography can help clarify the diagnosis. In a stable patient, management depends on the underlying etiology of the dyspnea.