title: Multisite near-infrared spectroscopy predicts elevated blood lactate level in children after cardiac surgery.
abstract: OBJECTIVE
  To determine if a relationship exists between regional oxyhemoglobin saturation (rSO(2)) measured at various body locations by near-infrared spectroscopy (NIRS) and blood lactate level in children after cardiac surgery.
  
  
  METHODS
  A prospective, observational study.
  
  
  METHODS
  A pediatric cardiac intensive care unit in a university hospital.
  
  
  METHODS
  Twenty-three children undergoing repair of congenital heart disease. Patients with single-ventricle physiology and/or residual intracardiac shunts were excluded.
  
  
  METHODS
  None.
  
  
  RESULTS
  Cerebral, splanchnic, renal, and muscle rSO(2) values were recorded every 30 seconds via NIRS for 24 hours postoperatively. Blood lactate levels measured minimally at 0, 2, 4, 6 and 24 hours postoperatively were correlated with rSO(2) values derived by averaging all values recorded during the 60 minutes preceding the blood draw. Twenty-three patients were enrolled with 163 lactate measurements and more than 39,000 rSO(2) observations analyzed. Cerebral rSO(2) had the strongest inverse correlation with lactate level followed by splanchnic, renal, and muscle rSO(2) (r = -0.74, p < 0.0001, r = -0.61, p < 0.0001, r = -0.57, p < 0.0001, and r = -0.48, p < 0.0001, respectively). The correlation improved by averaging the cerebral and renal rSO(2) values (r = -0.82, p < 0.0001). Furthermore, an averaged cerebral and renal rSO(2) value <or=65% predicted a lactate level >or=3.0 mmol/L with a sensitivity of 95% and a specificity of 83% (p = 0.0001).
  
  
  CONCLUSIONS
  Averaged cerebral and renal rSO(2) less than 65% as measured by NIRS predicts hyperlactatemia (>3 mmol/L) in acyanotic children after congenital heart surgery. Hence, this noninvasive, continuous monitoring tool may facilitate the identification of global hypoperfusion caused by low cardiac output syndrome in this population.
authors.affiliation: Division of Pediatric Cardiology, The Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: Sujata B
authors.initials: SB
authors.lastname: Chakravarti
authors.forename: Alexander J C
authors.initials: AJ
authors.lastname: Mittnacht
authors.forename: Jason C
authors.initials: JC
authors.lastname: Katz
authors.forename: Khahn
authors.initials: K
authors.lastname: Nguyen
authors.forename: Umesh
authors.initials: U
authors.lastname: Joashi
authors.forename: Shubhika
authors.initials: S
authors.lastname: Srivastava
mesh_terms: D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D011183:Postoperative Complications / Q000097:blood* / Q000209:etiology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
chemical_list: D019344:Lactic Acid