Effect of indomethacin on cerebral blood flow velocity of premature newborns.

Using the Doppler technique, the effect of therapeutic doses of indomethacin on the cerebral blood flow velocity (CBFV) of anterior cerebral arteries was studied in 13 preterm infants with patent ductus arteriosus. The first intravenous injection of indomethacin (0.2 mg/kg, group 1, n = 10) induced a significant decrease in the area under the velocity curve at 15 min (-22%), which was sustained until 120 min (-28%, p less than 0.005). In contrast, no significant change in CBFV occurred after the third dose (group 2, n = 7). In both groups, capillary blood gases, mean arterial blood pressure, and heart rate remained stable throughout the study. In 5 mechanically ventilated infants, the increase in CBFV secondary to suctioning was significantly attenuated after the first dose of indomethacin (p less than 0.02) but not after the third (p = 0.56). Thus, an initial dose of indomethacin may attenuate CBFV increases secondary to clinical manipulations in the preterm newborn.