Effect of doxapram on episodes of apnoea, bradycardia and hypoxaemia in preterm infants.
OBJECTIVE
To study the effect of doxapram on the frequency of apnoea, bradycardia and hypoxaemia.


METHODS
Fifteen infants, median gestational age at birth 27 weeks (range 24-30), age at study 27 days (12-60), with >/=6 episodes of bradycardia or hypoxaemia/6 h despite serum caffeine levels in the therapeutic range, received doxapram either intravenously (0.5-2 mg/kg/h) or orally (2-8 mg/kg every 2 h). Six-hour recordings of pulse oximeter saturation (S(P)O(2)), pulse waveforms, ECG, breathing movements and nasal airflow were performed immediately before as well as 1, 3 and 6 days after onset of treatment. Recordings were analysed for apnoea (>/=4 s), bradycardia (heart rate < 2/3 of baseline) and hypoxaemia (S(P)O(2) </=80%).


RESULTS
There was no difference between enteral and intravenous administration; results are therefore presented for the total group. Doxapram resulted in a significant decrease in the frequency of apnoea [22 (11-27) vs. 14 (7-23)/h, p < 0.01], bradycardia [3 (0-7) vs. 1 (0-3)/h, p < 0.01] and hypoxaemia [8 (0-18) vs. 2 (0- 17)/h, p < 0.01] already after 1 day of treatment, which was sustained throughout the 6-day study period. Side effects included an increase in the proportion of time spent awake [5 (0-24) vs. 12% (3-28), p < 0.01] and in gastric residuals [0% of feeding volume (0-5) vs. 4% (0-19), p < 0.05]. Enteral was switched to intravenous doxapram in 3 of 9 infants because of gastrointestinal side effects.


CONCLUSIONS
Doxapram substantially reduced the frequency of apnoea, bradycardia and hypoxaemia in these patients with caffeine-resistant apnoea of prematurity. Enteral administration, however, was not tolerated in a significant proportion (33%) of infants.
Poets
C F
CF
Department of Neonatology and Paediatric Pulmonology, Hannover Medical School, Hannover, Germany. poets.christian@mh-hannover.de
Darraj
S
S
Bohnhorst
B
B
D001049:Apnea / Q000517:prevention & control*; D001724:Birth Weight; D001919:Bradycardia / Q000517:prevention & control*; D002110:Caffeine / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use; D004315:Doxapram / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004351:Drug Resistance; D005865:Gestational Age; D006801:Humans; D000860:Hypoxia / Q000517:prevention & control*; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000517:prevention & control*; D007262:Infusions, Intravenous; D007441:Intubation, Gastrointestinal; D010100:Oxygen / Q000097:blood; D019141:Respiratory System Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
D019141:Respiratory System Agents; D002110:Caffeine; D004315:Doxapram; D010100:Oxygen