Measuring Cerebrospinal Fluid (CSF) Glucose Levels in Patients Under Going an Elective Cesarean Section With Spinal Anesthesia
Condition: Spinal Anesthesia
Study type: Observational

Summary: 
      This study will determine the level of glucose (sugar) in the CSF (fluid that surrounds the
      spinal cord) in 30 subjects having spinal anesthesia for cesarean section using a bedside
      glucose meter. Spinal anesthesia is done by injecting drugs through a needle into the CSF.
      Subjects will have 1/10 tsp of CSF removed at the time of spinal anesthesia to measure the
      level of glucose. Glucose meters measure glucose, usually in the blood, and they can be used
      in the operating room. This study will see whether a glucose meter will easily measure the
      level of glucose in CSF.
    

Detailed description: 
      Detailed Description Spinal anesthesia consists of putting drugs into the cerebrospinal fluid
      (CSF), the fluid that surrounds the spinal cord. This allows the subject to be awake but
      "numb" from the chest down during your operation. Spinal anesthesia is done by inserting a
      small needle (spinal needle) in the subject's back into the space (subarachnoid space)
      containing the CSF. Once the spinal needle is in the subarachnoid space a small amount of
      fluid (CSF) is seen coming out of the spinal needle, confirming that the needle is in the
      right space. The anesthesiologist then injects local anesthetic into the CSF to freeze or
      numb the area for your surgery and some pain medication, such as morphine, to relieve pain
      after the operation.

      CSF contains glucose (sugar) and the presence of glucose in the fluid that comes out of a
      spinal needle will confirm that the fluid is CSF. If spinal anesthesia is used for cesarean
      section following failed epidural anesthesia (may happen in women who had an epidural for
      labor pain relief who then need a cesarean section) it may be difficult to tell whether the
      fluid that comes out of the spinal needle is CSF or local anesthetic used for the epidural.
      In other words, the needle may be in the epidural space instead of the subarachnoid space and
      so the spinal anesthetic would not work. A simple bedside test to confirm that the fluid is
      CSF could potentially prevent this situation. Local anesthetic does not contain glucose so
      testing the fluid for glucose could help determine if the needle is in the proper space for
      spinal anesthesia.

      The study will determine the normal levels of CSF glucose using three different glucose
      meters (Nova Stat Strip, Abbott Precision Xtra and Roche Accucheck Inform 2 which are bedside
      devices that measure glucose). A glucose meter is used by people with diabetes to check their
      blood sugar levels using a drop of their blood. The results of this study will hopefully
      provide the basis for a further study that would look at whether it is possible to
      distinguish CSF from epidural fluid when spinal anesthesia is done following a failed
      epidural anesthetic. This could help prevent failures of spinal anesthesia in that situation.

      This is a prospective, observational study.

      The Cesarean Section and spinal anesthesia will continue as per usual practice at BCWH.
      Consenting subjects will receive the same drugs and all aspects of the anesthetic care will
      be the same except for two differences. The first, is that the anesthesiologist will collect
      a very small amount of CSF (0.5 mL which is 1/10 of a teaspoon) to measure the amount of
      glucose. This testing will be done in the operating room with the three glucose meters (Nova
      Stat Strip, Abbott Precision Xtra and Roche Accucheck Inform 2) and in the laboratory (using
      one of the two machines: 1)Vitros 9 or 2)Vitros 5,1 FS). Secondly, blood sugar level will be
      tested by taking up to three drops of blood from a pinprick in the subject's toe to compare
      with the CSF glucose level.
    

Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Parturients undergoing Cesarean delivery under spinal anesthesia at BC Women's Hospital
      
Biospecimen description: 
      Whole blood, CSF
    
Keywords: Glucose; CSF; Cesarean section, spinal anesthesia; Nova Stat Strip; Abbott Precision Xtra; Roche Accucheck Inform 2