TRANSCRANIAL DOPPLER MONITORING OF CEREBRAL BLOOD FLOW VELOCITY
DURING EXTRACORPOREAL MEMBRANE OXYGENATION IN SHEEP
Zhang Jing1, Fan Xunmei1, Song Guowei2,
Yin Hehua2, Qian Suyun2, Gan Xiaozhuang2,
Huang Weixiong2, et al
1 Intensive Care Unit, Beijing Children’s
Hospital, Beijing, China
2 Intensive Care Unit, Capital Institute of
Pediatrics, Beijing, China
Objective: To evaluate the transcranial Doppler
(TCD) – monitoring of cerebral blood flow velocity during extracorporeal
membrane oxygenation (ECMO) and the security of ECMO.
Methods: Using American Medsonics CDS TCD machine to
detect continuously the change of cerebral blood flow velocity (CBFV) at
time points of clamping of right carotid artery and vein, onset of ECMO,
pump flow increasing, decreasing and stop of ECMO. To detect CBFV
continually before ECMO, 2 hours after the stop of ECMO, every 24 hours
during the first week and every 48 hours during the second week after ECMO
management in 14 sheep and to give the cerebral morphological and pathological
examination to the 9 of the 14 sheep.
Results: (1) The general trend graph showed that the
CBFV decreased slightly after clamping of right carotid artery and vein,
indicating enough blood supply to the right hemi-globle of brain of sheep.
CBFV decreased, but still kept above 50% during the whole process of ECMO.
And the decreasing of CBFV were considered to be related to the low PCO2
during this period of ECMO. CBFV restored obviously at 2 hour after ECMO
stopping. Which indicated that the blood supplied to the right brain of
sheep was adequate despite the clamping of carotid artery and ECMO
management were given. (2) Sheep could stand, walk and eat food 2 to 3
hours after ECMO management, this further verified there was no
inefficiency of cerebral blood supply of right brain in sheep. (3) The
morphological examination showed no intracranial hemorrhage and normal
basic structure of brain tissues in sheep.
Conclusion: (1) Although the hemodynamic changes
were large, sheep could endure these changes. And ECMO management is
secured if the techniques can be mastered and given fluently. (2) The
present study has provided evidence that TCD has the advantages of
repeatable, real-time, rapid and long-period monitoring and is a valuable
monitor method during ECMO.