Cephalic Spread of Block With Head Down Tilt in Spinal Anaesthesia - A Randomised Controlled Study
Condition: Head-Down Tilt Following Spinal Anesthesia
Study type: Interventional

Summary: 
      Subarachnoid block has become an established and reliable method of providing anaesthesia for
      lower abdominal and lower limb surgeries. Several factors determine the spread of local
      anaesthetic solutions in CSF. Among them, patient position is an important determining
      factor. Anesthesiologists give various degrees of head down tilt which they believe is both
      safe for the patient and will result in adequate level of block. Often these are arbitrarily
      done by the operator as most of the operation theatre tables are not equipped with any device
      to measure the accurate degree of tilt. As there is no agreement on the effect of
      Trendelenberg position on height of subarachnoid block, the current clinical study will be
      undertaken to estimate the effect of operation theatre table tilt at the time of lumbar
      puncture on the height of subarachnoid block.
    

Detailed description: 
      Subarachnoid block has become an established and reliable method of providing anaesthesia for
      lower abdominal and lower limb surgeries. A definitive advantage that subarachnoid block
      provides is the profound nerve block that can be produced in a large part of the body by the
      relatively simple injection of a small amount of local anaesthetic. Twenty-five factors have
      been invoked as determinants of the spread of local anaesthetic solutions in CSF. Among them,
      patient position is an important determining factor.

      Operation theatre table tilts have been used to influence the spread of hyperbaric solution
      to ultimately influence the final height of the block. Studies have shown that a 10 degree
      head down tilt can result in cephalad spread of analgesia when compared to the horizontal
      group. So, in cases where the spinal block level was not high enough to perform a given
      surgery, the Trendelenburg position has been used to extend the level of the block. Hence, it
      is assumed that a higher level of block can be achieved with a smaller volume of the local
      anaesthetic agent, thus reducing the side effects. But others have noted that there was no
      statistically significant increase in the level of block even with 15 degree head down tilt.

      In spite of this, anesthesiologists give various degrees of head down tilt which they believe
      is both safe for the patient and will result in adequate level of block. Often these are
      arbitrarily done by the operator as most of the operation theatre tables are not equipped
      with any device to measure the accurate degree of tilt.

      An application called clinometer that utilizes the gyroscope sensor and determines the plane
      of the gadget in vertical as well as horizontal directions has been described. This
      application can be used to measure the exact degree of tilt given after sub arachnoid block.

      As there is no agreement on the effect of Trendelenberg position on height of subarachnoid
      block, the current clinical study will be undertaken to estimate the effect of operation
      theatre table tilt at the time of lumbar puncture on the height of subarachnoid block.
    

Intervention name(s): Group X - head low tilt; Group Y - head low tilt; Group C - neutral
Intervention type(s): Procedure; Procedure; Procedure
Intervention description(s): spinal anaesthesia was given with table in neutral positon. 10 degree head low position was maintained for 10 minutes following spinal anaesthesia; the table was put in 10 degree head low position before proceeding to give spinal anaesthesia. Head low position was maintained for 10 minutes following spinal; spinal anaesthesia was given with table in neutral positon. Patient was maintained in supine position for 10 minutes following spinal anaesthesia
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Patients were randomly allocated to one of the 3 groups by closed envelope method
Masking: Triple (Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Anesthetics, Local; Head-Down Tilt; Anesthesia, Spinal; hypotension