Serum and CSF levels of neuron-specific enolase (NSE) in cardiac surgery with cardiopulmonary bypass: a marker of brain injury?
We investigated whether neuron-specific enolase (NSE) in serum or cerebrospinal fluid (CSF) reflects subtle or manifest brain injury in children undergoing cardiac surgery using cardiopulmonary bypass (CPB). NSE was measured in serum (s-NSE) before, and up to, 102 h after surgery in 27 children undergoing cardiac surgery with CPB. In 11 children, CSF-NSE was also measured 48 or 66 h post-surgery. As erythrocytes contain NSE, hemoglobin concentration in the samples was determined spectrophotometrically at 550 nm (cut-off limit: absorbance 0.4 = 560 mg/l) in 14 children and in a further 13 children by spectroscopic multicomponent analysis (cut-off limit 5 micromol/l = 80 mg/l). One hundred and one of 214 post-operative serum samples (47%) had to be discarded because of hemolysis (18% spectrophotometrically at 550 nm and 88% with spectroscopic multicomponent analysis). On the first and second post-operative day, the median s-NSE values were significantly higher when compared with samples taken after 54 h or longer (P = 0.008 and P = 0.002). All CSF-NSE levels were within the normal range and below the s-NSE measured in the same patient. Although in our study elevated s-NSE seems to indicate brain injury in CPB-surgery, the low concentration of NSE in the post-operative CSF of 11 children puts the neuronal origin of s-NSE in question. NSE from other non-neuronal tissues probably contributes to the elevated s-NSE. Additionally, normal post-operative CSF-NSE values in two children with post-operative neurological sequelae might question the predictive value of CSF-NSE with regard to brain injury.
Schmitt
B
B
Department of Pediatrics, University of Zürich, Switzerland. smibla@kispi.unizh.ch
Bauersfeld
U
U
Schmid
E R
ER
Tuchschmid
P
P
Molinari
L
L
Fanconi
S
S
Bandtlow
C
C
D015415:Biomarkers; D001921:Brain / Q000201:enzymology; D001927:Brain Diseases / Q000097:blood / Q000134:cerebrospinal fluid / Q000201:enzymology*; D002675:Child, Preschool; D001026:Coronary Artery Bypass; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000134:cerebrospinal fluid / Q000601:surgery; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009206:Myocardium / Q000201:enzymology; D010751:Phosphopyruvate Hydratase / Q000097:blood* / Q000134:cerebrospinal fluid*; D011183:Postoperative Complications / Q000097:blood / Q000134:cerebrospinal fluid / Q000201:enzymology*
D015415:Biomarkers; D010751:Phosphopyruvate Hydratase