Hypocarbia in preterm infants with periventricular leukomalacia: the relation between hypocarbia and mechanical ventilation.
OBJECTIVE
The aim of this study was to elucidate the relationship between mechanical ventilation and hypocarbia in infants with periventricular leukomalacia (PVL).


METHODS
Matched pair analysis was conducted for 26 infants with PVL and 26 with normal development, who were born between 27 and 32 weeks' gestational age and required mechanical ventilation. The time-averaged carbon dioxide (CO(2)) index, PaCO(2), and pH were calculated every 24 hours for samples obtained from indwelling arterial catheters within the first 72 hours of life. The time-averaged respiratory rate of the ventilator (RR), peak inspiratory pressure (PIP), mean airway pressure (MAP), and ventilator index (VI) were also determined. The time-averaged total respiratory rate (TRR) was determined by observing the movement of the chest wall. The patients' characteristics, antenatal and neonatal variables, and electroencephalographic findings were also compared.


RESULTS
The time-averaged CO(2) index was larger, the time-averaged CO(2) lower and the time-averaged pH higher in infants with PVL than in those with normal development on the third day of life. There was no significant difference in the time-averaged RR, PIP, MAP, or VI on any day. TRR was larger in the PVL group than in the control group on each day, but there was no significant difference. No significant difference was observed in the clinical characteristics or neonatal variables. Electroencephalographic abnormalities within 48 hours of life were more frequent in infants with PVL than in those with normal development.


CONCLUSIONS
Hypocarbia was associated with PVL because the time-averaged CO(2) index was larger and the time-averaged PaCO(2) lower in infants with PVL than in those with normal development. However, the ventilator settings were similar among the infants with and without PVL.
Okumura
A
A
Department of Pediatrics, Nagoya University, School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan. okumura@med.nagoya-u.ac.jp
Hayakawa
F
F
Kato
T
T
Itomi
K
K
Maruyama
K
K
Ishihara
N
N
Kubota
T
T
Suzuki
M
M
Sato
Y
Y
Kuno
K
K
Watanabe
K
K
D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000378:metabolism*; D004569:Electroencephalography; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016857:Hypocapnia / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000503:physiopathology*; D007969:Leukomalacia, Periventricular / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D012121:Respiration, Artificial; D012131:Respiratory Insufficiency / Q000150:complications / Q000503:physiopathology* / Q000628:therapy
D002245:Carbon Dioxide