Brain hemodynamic effects of doxapram in preterm infants.

BACKGROUND

Doxapram is a respiratory stimulant widely used for the treatment of idiopathic apnea of prematurity, although it has been demonstrated that it can induce a transient decrease of cerebral blood flow and that isolated mental delay in infants weighing <1,250 g is associated with the total dosage and duration of doxapram therapy.

OBJECTIVES

To evaluate the effects of doxapram on cerebral hemodynamics in preterm infants using cerebral Doppler ultrasonography and near-infrared spectroscopy.

METHODS

Preterm infants who required treatment with doxapram for apnea of prematurity unresponsive to caffeine were treated with doxapram at an hourly dose of 0.5 mg x kg(-1).h(-1), followed by 1.5 and 2.5 mg x kg(-1).h(-1).

RESULTS

20 preterm infants were studied. Doxapram induced a significant decrease of oxygenated hemoglobin (O(2)Hb) and cerebral intravascular oxygenation (HbD = O(2)Hb - HHb) and an increase of HHb and CtOx concentrations, while cerebral blood volume and cerebral blood flow velocity did not change.

CONCLUSIONS

Doxapram infusion induces the increase of cerebral oxygen consumption and requirement and the contemporary decrease of oxygen delivery probably mediated by a decrease of cerebral blood flow. Caution must be recommended in prescribing this drug for apnea of prematurity.