Esophageal saturation during antegrade cerebral perfusion: a preliminary report using visible light spectroscopy.
BACKGROUND
Visible light spectroscopy (VLS) is newer technology that measures real-time tissue oxygenation. It has been validated in detecting mucosal ischemia in adults. During complex neonatal heart surgery, antegrade cerebral perfusion (ACP) maintains cerebral saturation. Whether ACP maintains peripheral tissue perfusion in humans is not known.


METHODS
Five patients undergoing neonatal open heart surgery with hypothermic cardiopulmonary bypass (CPB) were studied using a VLS esophageal probe in addition to bilateral near infrared cerebral oximetry. Three of five patients required ACP for arch repair, while two patients did not. VLS and cerebral saturation data were collected and analyzed in 5 min intervals prior to CPB, during CPB, and during ACP.


RESULTS
In the two patients undergoing heart surgery with routine hypothermic CPB, both cerebral and esophageal saturations were maintained. However in all three neonates requiring ACP, although cerebral saturations did not decrease, esophageal saturation fell below the ischemic threshold (35%). Following establishment of normal CPB, esophageal saturation returned to baseline.


CONCLUSIONS
Antegrade cerebral perfusion maintains cerebral oxygen delivery, however, it does not adequately perfuse the esophagus in neonates. This could have clinical implications.
Heninger
Carly
C
Stanford School of Medicine, Stanford, CA 94305, USA.
Ramamoorthy
Chandra
C
Amir
Gabriel
G
Kamra
Komal
K
Reddy
V Mohan
VM
Hanley
Frank L
FL
Brock-Utne
John G
JG
D002545:Brain Ischemia / Q000175:diagnosis; D006348:Cardiac Surgical Procedures / Q000295:instrumentation*; D002315:Cardiopulmonary Bypass; D002560:Cerebrovascular Circulation; D004947:Esophagus / Q000098:blood supply*; D006801:Humans; D007036:Hypothermia, Induced; D007231:Infant, Newborn; D007511:Ischemia / Q000175:diagnosis; D008027:Light; D016343:Monitoring, Intraoperative; D010092:Oximetry / Q000295:instrumentation*; D010100:Oxygen / Q000378:metabolism*; D013057:Spectrum Analysis / Q000295:instrumentation*
D010100:Oxygen