Does indomethacin affect the control of breathing in premature infants?

The effect of indomethacin on the control of breathing was simultaneously evaluated in 10 premature infants who had significant patent ductus arteriosus and received indomethacin therapy. In an attempt to maintain high plasma level in these infants of advanced postnatal age (≥6 weeks), indomethacin was administered intravenously at a dosage of 0.3 mg/kg, at 8-hour intervals, for a total of three doses. Following indomethacin therapy, there was a significant increase in tidal volume, minute ventilation, tidal volume/inspiratory time and in airway pressure (P_0.1, P(max)) generated during airway occlusion. Seven infants required lower ventilatory rates after study. In spite of desirable plasma indomethacin level, there was no significant improvement in echo left atrium/aortic root dimension ratio, cardiovascular dysfunction score and blood pH, PO₂ and PCO₂. None of the infants showed clinical evidence of ductus closure. The results of the study suggested that indomethacin may stimulate respiration and that endogenous prostaglandin may play a role in the regulation of breathing.