title: Baseline cerebral oximetry values in cardiac and vascular surgery patients: a prospective observational study.
abstract: OBJECTIVE
  This study was conducted to evaluate baseline INVOS values and identify factors influencing preoperative baseline INVOS values in carotid endarterectomy and cardiac surgery patients.
  
  
  METHODS
  This is a prospective observational study on 157 patients (100 cardiac surgery patients, 57 carotid endarterectomy patients). Data were collected on factors potentially related to baseline INVOS values. Data were analyzed with student's t-test, Chi-square, Pearson's correlation or Linear Regression as appropriate.
  
  
  RESULTS
  100 cardiac surgery patients and 57 carotid surgery patients enrolled. Compared to cardiac surgery, carotid endarterectomy patients were older (71.05 +/- 8.69 vs. 65.72 +/- 11.04, P < 0.001), with higher baseline INVOS (P < 0.007) and greater stroke frequency (P < 0.002). Diabetes and high cholesterol were more common in cardiac surgery patients. Right side INVOS values were strongly correlated with left-side values in carotid (r = 0.772, P < 0.0001) and cardiac surgery patients (r = 0.697, P < 0.0001). Diabetes and high cholesterol were associated with significantly (P < 0.001) lower INVOS and smoking was associated with higher INVOS values in carotid, but not in cardiac surgery patients. Age, sex, CVA history, Hypertension, CAD, Asthma, carotid stenosis side and surgery side were not related to INVOS. Multivariate analysis showed that diabetes is strongly associated with lower baseline INVOS values bilaterally (P < 0.001) and explained 36.4% of observed baseline INVOS variability in carotid (but not cardiac) surgery.
  
  
  CONCLUSIONS
  Compared to cardiac surgery, carotid endarterectomy patients are older, with higher baseline INVOS values and greater stroke frequency. Diabetes and high cholesterol are associated with lower baseline INVOS values in carotid surgery. Right and left side INVOS values are strongly correlated in both patient groups.
authors.affiliation: Department of Cardiac Surgery, University of Ioannina School of Medicine, Ioannina, Greece.
authors.forename: Nikolaos G
authors.initials: NG
authors.lastname: Baikoussis
authors.forename: Menelaos
authors.initials: M
authors.lastname: Karanikolas
authors.forename: Stavros
authors.initials: S
authors.lastname: Siminelakis
authors.forename: Miltiadis
authors.initials: M
authors.lastname: Matsagas
authors.forename: Georgios
authors.initials: G
authors.lastname: Papadopoulos
mesh_terms: D000368:Aged; D001921:Brain / Q000378:metabolism*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D010092:Oximetry; D012307:Risk Factors; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods; D020521:Stroke / Q000209:etiology / Q000503:physiopathology