The provided text is a comprehensive overview of neonatal perinatal hemodynamic syndrome (PPHN), its diagnosis, management, and treatment strategies. Here's a summary of the key points: **Diagnosis** * Echocardiography: To screen for and diagnose PPHN, as well as to rule out structural heart lesions. * Echocardiography with Doppler and color-flow mapping: To assess intracardiac shunts, pulmonary arterial pressures, and perfusion. * Cranial ultrasonography: To evaluate for intraventricular bleeding, peripheral hemorrhage, or infarct if ECMO is being considered. * Brain computed tomography scanning or magnetic resonance imaging: To evaluate central nervous system injury. **Procedures** * Cardiac catheterization: Rarely utilized to exclude congenital heart disease; echocardiographic findings are typically diagnostic. **Management** * Continuous monitoring of oxygenation, blood pressure, and perfusion. * Maintaining normal body temperature. * Correction of electrolytes/glucose abnormalities and metabolic acidosis. * Nutritional support. * Minimal stimulation/handling of the newborn. * Minimal use of invasive procedures (e.g., suctioning). **Medical therapy** * Inotropic support (e.g., dopamine, dobutamine, milrinone). * Surfactant administration: For premature and full-term newborns with parenchymal lung disease. * Endotracheal intubation and mechanical ventilation: To maintain normal functional residual capacity by recruiting areas of atelectasis. * High-frequency ventilation: Used in newborns with underlying parenchymal lung disease and low lung volumes. * Correction of hypoglycemia, hypocalcemia, acidosis, and alkalosis. * Induced paralysis (controversial; typically reserved for newborns who cannot be treated with sedatives alone). * Extracorporeal membrane oxygenation (ECMO): Used when optimal ventilatory support fails to maintain acceptable oxygenation and perfusion. **Pharmacotherapy** * Inhaled pulmonary vasodilators (e.g., nitric oxide) and supplemental oxygen. * Systemic vasodilators: Potentially beneficial for chronic PPHN after the newborn period (e.g., prostacyclin, phosphodiesterase inhibitors, endothelin receptor antagonists). * Prostaglandin E1 if the ductus arteriosus is closed or restrictive. This summary highlights the importance of a multidisciplinary approach to managing PPHN, involving continuous monitoring, supportive care, and pharmacological interventions tailored to each patient's needs.