Ductus Botalli is a physiological part of intrauterine bloodstream which connects aorta and pulmonary artery because of the undeveloped fetal lungs. Its’ closure signifies final transition of intrauterine bloodflow to extrauterine conditions. Persistently patent ductus arteriosus (PDA) may increase the possibility of developing various complications such as bronchopulmonar dysplasia, respiratory distress syndrome and death. Nevertheless, we should dismiss opinion that PDA is harmful by itself. High rate of spontaneous PDA closure (especially in infants >1000g), shortage of long-term effects of pharmacological or surgical treatment and development of complications caused by therapy raise the question on the usefulness of treatment. In any case, the presence of PDA should not be neglected. Any therapy with the aim of PDA closure should be avoided. There are various measures of infant care during the time of waiting for PDA to close. Therapy should be based on decreasing of left to right shunt and cardiac afterload with medications such as captopril and nitroprusside; increasing the mean airway pressure using PEEP or CPAP ; decreasing the hydrostatic pressure and left atrial pressure by fluid restriction and administration of diuretics.