Cerebrospinal Fluid Glucose Measurement at Point-of-Care

The ability to confirm that the fluid obtained during attempted spinal anesthesia after failed epidural anesthesia is cerebrospinal fluid (CSF) would be useful to the obstetric anesthesiologist. This study was designed to determine whether 3 point-of-care glucose devices (Precision Xtra [Abbott Point of Care], StatStrip Glucose Monitor [Nova Biomedical], and ACCU-CHEK Inform II [Roche Diagnostics]) would reliably measure glucose in CSF during routine spinal anesthesia for cesarean section. A sample of CSF was removed after dural puncture, and glucose was tested using all 3 devices at point-of-care. Results were compared with laboratory CSF glucose measurement (Vitros instruments [Ortho Clinical Diagnostics]). Ease of use of the 3 glucose monitors in the operating room setting and the relationship between blood and CSF glucose levels were also examined. Thirty women were studied. With one exception, blood glucose levels were normal. The StatStrip Glucose Monitor and the ACCU-CHEK Inform II gave similar results of CSF glucose as a percentage of blood glucose in most samples. There was no correlation between the length of fast and CSF glucose results. Both the StatStrip Glucose Monitor and the ACCU-CHEK Inform II showed good agreement with laboratory CSF glucose. There was a significant positive bias with the Precision Xtra device. This study confirmed that some point-of-care devices can measure CSF glucose level reliably in the operating room setting. Further studies are needed to see if this will prove useful during attempted spinal anesthesia after failed epidural anesthesia.