SCMC Ductus Arteriosus e Closure occurs in two stages 80%Functional closure occurs 24 hours after birth This is reversible in the presence of hypoxemia or hypovolemia 80% Permanent closure occurs in 3 months 95% Permanent closure occurs in 3 months e Fibrous connective tissue forms permanently seals the lumen This becomes the ligamentum arteriosumDuctus Arteriosus ⚫ Closure occurs in two stages – 80% Functional closure occurs 24 hours after birth ⚫ This is reversible in the presence of hypoxemia or hypovolemia – 80% Permanent closure occurs in 3 months – 95% Permanent closure occurs in 3 months ⚫ Fibrous connective tissue forms & permanently seals the lumen – This becomes the ligamentum arteriosum