Abstract 1126 Poster Session IV, Tuesday, 5/4 (poster 265)

Caffeine and theophylline are widely used in preterm infants for apnea of prematurity. Previous studies showed that theophylline decreased cerebral blood flow (CBF), but caffeine does not. Aim of the study. To investigate the acute effects on CBF of caffeine and theophylline in preterm infants using near-infrared spectroscopy (NIRS). Methods. Forty preterm infants affected by apnea of prematurity were studied with parenteral consent. NIRS (NIRO 300, Hamamatsu Photonic, Italy) was used from 30 minutes before to 60 minutes after the administration of caffeine (2.5 mg/kg i.v.) or theophylline (1.25 mg/kg i.v.). The optodes were placed on the forehead. Changes of oxygenated haemoglobin (O2Hb), deoxygenated haemoglobin (HHb), oxidized-reduced cytocrome aa3 (CtOx), and tissue oxygenation index (TOI=O2Hb/total Hb) were recorded. CBF velocity in the pericallosal artery was measured using doppler ultrasonography, and expressed as pulsatility index (PI). Changes in cerebral blood volume (CBV microL/100 gm of brain tissue) was calculated with the following formula: changes in concentration of total haemoglobin × 0.89 / arterial haemoglobin concentration (gm/dL). Results. Twenty infants (GA 30.4±3.0 wks; BW 1041±332 gm) were treated with caffeine and 20 (GA 29.4±1.4 wks; BW 1087±262 gm) with theophylline. All patients had a normal cerebral ultrasound and stable vital parameters (HR, RR, systemic arterial pressure, SaO2) during the study period. None was mechanically ventilated and only two were oxygen-dependent. Treatment with caffeine led to a slight increment of O2Hb (0.9±5.5 micromol/L), HHb (1.0±3.6 micromol/L), and of CBV (148 microL/100 gm of brain tissue) after 45 minutes from administration; a return to baseline was observed after 60 minutes. The mean changes of CtOx (range -0.2±0.6 - 0.2±2.7) and the mean values of TOI (70.1±6.6 - 68.5±9.1%) and IR (range 0.73±0.06 - 0.74±0.06) did not change during the study period. Treatment with theophylline led to a slight increment of O2Hb (1.28±2.4 micromol/L), HHb (1.37±1.78 micromol/L) and of CBV (200 microL/100 gm of brain tissue) after 30 minutes from administration, while a return to baseline was observed after 60 minutes. The mean change of CtOx (range -0.02±0.1 - 0.26±2.2) and the mean values of TOI (range 64.6±13.0 - 68.1±12.0%) and IR (range 0.73±0.05 - 0.76±0.06) did not change during the study period. Conclusion. We found that the maintenance doses of caffeine and theophylline do not affect significantly cerebral hemodynamics, and this is noticeable due to their wide and long use in the preterm infants.

We state that were not funded by commercial sources and we had not equity in any company