Epidural Computer Controlled System for the Epidural Space Verification
Condition: Epidural
Study type: Observational

Summary: 
      The purpose of this study will be to evaluate the inter-rater agreement, or concordance,
      between an expert anaesthesiologist and the CompuFlo® Epidural Computer Controlled System for
      the epidural space verification.

      Primary study endpoint will be successful concordance of identification of ligamentum flavum
      and epidural space during a standard epidural procedure in pregnant patient. Secondary
      outcome will be successful concordance of identification of bony contact during a standard
      epidural procedure in pregnant patient.
    

Detailed description: 
      After skin local anesthesia and after the subcutaneous insertion of the epidural Tuohy
      needle, an independent investigator will make the O point of the CompuFlo® device that will
      be connected, via a three way stopcock, to the Tuohy needle in order to register, in a double
      blind way, the delta of pressures encountered by the needle during its advancement.

      When the operator will reach the supraspinous ligament, a slight resistance will be
      encountered due to the nature of the bevel, and the density of the ligament. As soon as this
      resistance will be felt, the operator immediately will tell the investigator who will flag
      the CompuFlo® device. If no sensation will be felt the operator will tell "none" to the
      investigator.

      The needle will be then advanced through the loose interspinous ligament which typically
      offers much less resistance than the sopraspinous ligament (often felt as a "no resistance
      feeling" in the obstetric patient). Once again, as soon as this loss or reduced or no
      resistance sensation is felt, the operator immediately will tell the investigator who will
      flag the CompuFlo® device. If no sensation will be felt the operator will tell "none" to the
      investigator.

      According to the standard epidural technique, the point of the needle will be further
      advanced. The feeling of a greater increase of resistance, often associated with a "crunch",
      usually indicates the initial penetration of the needle in the rear wall of the ligamentum
      flavum. As soon as this resistance or "crunch" is felt, the operator immediately will tell
      the investigator who will flag the CompuFlo® device.

      Then, the operator will remove the stylet and gently will attach to the needle a disposable
      10 mL loss of resistance syringe containing a few millimeters (5-7 mL) of sterile saline
      solution and will open the three way stopcock in order to record both the pressures
      given-and-received by the CompuFlo® and the pressure produced by the operator's hand.

      Constant, unremitting pressure will be now exerted on the plunger of the syringe by the thumb
      of the dominant hand of the operator in order to obtain the needle advancement solely by
      means of the pressure exerted by the operator on the plunger of the syringe.

      As the point of the needle will emerge from the ligamentum flavum into the epidural space,
      the resistance suddenly will disappear and the advancement of the needle immediately will
      stop, (since the driving force exerted on the piston is discharged by the sudden entering of
      the liquid in the epidural space). As soon as this loss of resistance is felt, the operator
      immediately will tell the investigator who will who will flag the CompuFlo® device. The
      operator will stop the procedure for at least 10 seconds to allow the investigator to record
      the static epidural pressures.
    

Observational model: Other
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Healthy parturients
      
Keywords: Epidural technique