Clinical Outcomes of High-Dose Nitroglycerine in Sympathetic Crashing Acute Pulmonary Edema in the Emergency Department: A Retrospective Institutional Study

Background: Sympathetic crashing acute pulmonary edemais a life-threatening form of acute heart failure characterized by severe hypertension, respiratory distress, and rapid clinical deterioration. Conventional low-dose nitroglycerine may be insufficient to counteract the extreme afterload. HDN (High-Dose Nitroglycerine), combined with NIV (Non-Invasive Ventilation), has been proposed to achieve faster hemodynamic stabilization. This study evaluates clinical outcomeof HDN in SCAPE, with a focus on symptom resolution and emergency department length of stay.Methods: This retrospective cohort study included 35 adult patients presenting with SCAPE (Sympathetic crashing acute pulmonary edema) between December 2023 and December 2025. All patients received HDN (bolus 800–1000 mcg and infusion >100 mcg/min) along with NIV. Clinical data were extracted from electronic health records. Primary outcomes included symptom resolution at 6 hours and ED length of stay. Secondary outcomes were the need for intubation, ICU admission, mortality, and hypotension. Statistical analysis involved a paired t-test/Wilcoxon test and a chi-square/Fisher’s exact test, with p<0.05 considered significant.Results: The mean age was 60.54 ± 12.86 years, with 57.2% patients above 60 years. Significant improvement was observed in all clinical parameters at 6 hours: respiratory rate (−11.54), systolic BP (−52.71 mmHg), MAP (−32.77), heart rate (−32.29), and SpO₂ (+13.51) (p<0.001). Symptom resolution was achieved in 88.6% of patients. The mean ED length of stay was 6.97 ± 1.89 hours. Intubation and ICU admission rates were 11.4% each, while mortality was 5.7%. No cases of hypotension were observed. Failure of symptom resolution was significantly associated with worse outcomes and prolonged ED stay.Conclusion: High-dose nitroglycerine combined withNIV is an effective and safe strategy for rapid stabilization of SCAPE patients. It significantly improves clinical parameters, reduces ED length of stay, and is associated with low rates of complications, supporting its use as a first-line therapy in emergency settings.