The present study was limited by its retrospective, observational nature, the use of a basic echocardiographical marker for assisting in the determination of PDA significance and the long time period of the study. The exclusion of infants who died in the first seven days of life removed 11 deaths from the nonligation subgroups and could be seen as biasing against ligation from a mortality perspective; however, retrospectively attributing these deaths to the PDA or its medical management was not possible. The primary reason for ligation (ie, persistent ventilatory requirement) is consistent with current practice in a large American centre. Still, due to the long time period of this study, two PDA of the same clinical significance in similar infants may not have been treated similarly and vice versa. Also, without the use of screening echocardiography, we are unable to comment on the actual spontaneous closure rate of untreated PDA. This lack of clarity and standardization negatively affects the ability to generalize our data; however, we suspect it reflects the practice in many NICUs. Much of the literature around the PDA is nonrandomized and contains a degree of ambiguity around the indication for treatment and the treatment modality. Lack of rigorous standards for classifying the specific hemodynamic repercussions of a PDA may explain why conclusive answers to improving outcomes with PDA management have not yet been found.
In the present retrospective study of a large cohort of extremely premature infants, the rate of PDA ligation was 64% despite multiple indomethacin courses. While most repeated indomethacin courses were unsuccessful, no notable side effects were seen. Ligation was associated with a longer duration of mechanical ventilation and NICU stay and a trend toward decreased mortality. A prospective, randomized study is needed to define which management approach is best (medical, surgical, and/or noninterventional), and this should be done after further studies clearly define a hemodynamically significant PDA that will result in morbidity and/or mortality unless treated. Online shopping will cost you less money and will take less time, because you can find efficient sale cialis tablets with generous discounts at the pharmacy that proved its reputability and desire to help by offering best level of service and most efficient drugs.