Cerebral oxygen saturation and electrical brain activity before, during, and up to 36 hours after arterial switch procedure in neonates without pre-existing brain damage: its relationship to neurodevelopmental outcome.
OBJECTIVE
To monitor the pattern of cerebral oxygen saturation (rSat), by use of NIRS, in term infants before, during and after the arterial switch operation and to evaluate its relation to neurodevelopmental outcome.


METHODS
In 20 neonates without pre-existing brain damage hemodynamics and arterial oxygen saturation (AO2-Sat) were monitored simultaneously with rSat and amplitude-integrated EEG (aEEG) from 4 h to 12 h before up to 36 h after cardiopulmonary bypass (CPB) and short duration of cardiac arrest during deep hypothermia (DHCA). The Bayleys developmental scale was performed at 30 months.


RESULTS
Before surgery rSat was <50% in 16 patients. During CPB rSat increased to normal values, with a sharp decrease during brief CA (median 6.5 min). Post-CPB rSat showed a transient decrease (30-45%) despite normal PaO2 with sustained normalization after 6-26 h. Recovery time of the rSat seemed longer when pre-operative rSat was below 35%, and for lower minimum nasopharyngeal temperature and longer duration of CPB and of DHCA. Recovery time of the aEEG varied and did not correlate with normalization of rSat. Neurodevelopmental outcome was normal in all but two patients. Patients with lower pre-operative rSat (<35%) tended to have lower DQ (developmental quotient) scores at 30-36 months. (median: mental 102 and motor 101 (range 58-125) compared with mental 100 and motor 110 (range 83-125))


CONCLUSIONS
Despite prompt normalization of circulation and oxygenation after surgery, recovery of rSat of the brain took 6-26 h, probably because of higher energy demand after CPB. Pre-operative cerebral oxygenation may be underestimated as a possible cause of adverse post-operative outcome.
Toet
Mona C
MC
Department of Neonatology, KE 04.123.1, University Medical Center Utrecht/ Wilhelmina Children's Hospital, P.B. 85090, 3508 Utrecht, The Netherlands. M.Toet@WKZ.AZU.nl
Flinterman
Annebeth
A
Laar
Ingrid van de
Iv
Vries
Jaap W de
JW
Bennink
Ger B W E
GB
Uiterwaal
Cuno S P M
CS
Bel
Frank van
Fv
D001921:Brain / Q000502:physiology*; D001923:Brain Chemistry / Q000502:physiology*; D002315:Cardiopulmonary Bypass; D002560:Cerebrovascular Circulation / Q000502:physiology; D003627:Data Interpretation, Statistical; D004558:Electric Stimulation; D004569:Electroencephalography; D004594:Electrophysiology; D005500:Follow-Up Studies; D006324:Heart Arrest, Induced; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007036:Hypothermia, Induced; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D009420:Nervous System / Q000000981:diagnostic imaging / Q000254:growth & development*; D010100:Oxygen / Q000097:blood*; D019265:Spectroscopy, Near-Infrared; D014188:Transposition of Great Vessels / Q000601:surgery; D016896:Treatment Outcome; D014463:Ultrasonography
D010100:Oxygen