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.


OBJECTIVE
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.
Dani
Carlo
C
Department of Surgical and Medical Critical Care, Section of Neonatology, Careggi University Hospital of Florence, Florence, Italy. cdani@unifi.it
Bertini
Giovanna
G
Pezzati
Marco
M
Pratesi
Simone
S
Filippi
Luca
L
Tronchin
Michele
M
Rubaltelli
Firmino F
FF
D001049:Apnea / Q000188:drug therapy; D001724:Birth Weight; D001783:Blood Flow Velocity / Q000187:drug effects; D001921:Brain / Q000098:blood supply*; D016022:Case-Control Studies; D004315:Doxapram / Q000008:administration & dosage / Q000009:adverse effects*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000188:drug therapy*; D010100:Oxygen / Q000097:blood; D010108:Oxyhemoglobins / Q000032:analysis; D011446:Prospective Studies; D019141:Respiratory System Agents / Q000008:administration & dosage / Q000009:adverse effects*; D012189:Retrospective Studies
D010108:Oxyhemoglobins; D019141:Respiratory System Agents; D004315:Doxapram; D010100:Oxygen