This nursing case study focuses on Mrs. Brown, a patient presenting with symptoms of dyspnea, low oxygen saturation, and atrial fibrillation with chronic heart failure. The assignment addresses the pathogenesis of her clinical manifestations, linking pulmonary congestion and reduced cardiac output to the activation of RAAS and SNS. It details nursing strategies, including oxygen administration and positioning, based on established guidelines. Finally, the study explains the mechanisms of action of the two drugs administered: Furosemide (Lasix) and Glyceryl Trinitrate (GTN), highlighting their roles in managing pulmonary edema, hypertension, and heart failure. The study provides an in-depth analysis of Mrs. Brown's case, integrating pathophysiology, nursing interventions, and pharmacological treatments to provide comprehensive patient care.