Medición bilateral de la saturación yugular de oxígeno

Abstract

Summary Objective The objetive of this study was to obtain information about cerebral hemodynamics through retrograde cannulation of both internal jugular veins and monitoring jugular bulb oxigen saturation. Material and methods Fourteen (14) patients admitted to our ICU between July of 1994 and April of 1995 were prospectively studied. The intracranial pressure (ICP) was monitored and bilateral cannulation of the internal yugular vein was performed. In 9 patients, one of the two veins was channeled with an optic fiber catheter for continous monitoring at oxigen jugular saturation (SyO 2 )’ Simultaneus samples were obtained every 8 hours from both jugular veins for measuring SyO 2 whenever therapeutic changes were needed or before an increase in the ICP was observed. A total of 140 measurements were performed (mean 10 per patient). A variance analysis, t of student and simple linear regression analysis of the pars obtained in the SyO 2 were performed. Furthermore we studied the influence of the type of intracranial pathology as assessed by cranial computerized tomography (CT), as well as at different levels of raised IPC. Results Average monitoring time was 7.2 days (311). The brain injury in the CT was considered focal in 8 patients and mixed (focal + diffused) in 6. The correlation between the left and right SyO 2 was r = 0.68 (p 20, >30 and >40 mm Hg was r = 0.66, r = 0.79, r = 0.85 and r = 0.89, respectively. Clinical discordance between bilateral measurements was over 30% of these in 50% of the patients. Conclusion The SyO 2 obtained through retrograde cannulation from both jugular veins maintains a correct positive correlation that improves in intracranial hypertension situations. Correlation is better in patients with mixed CT lesion than in those with focal pathology. Our study could not determine which of the two jugular veins provided more reliable information of about intracranial hemodynamics. Consequently, we do not support the used of bilateral SyO 2 monitoring in the clinical rutine.