Comparison of Three Different Sitting Positions for Performing Combined Spinal-Epidural Anesthesia
Condition: Anesthesia; Adverse Effect, Spinal and Epidural; Hip Arthropathy; Knee Arthropathy
MeSH terms: Joint Diseases
Study type: Interventional

Summary: 
      In this prospective and randomized study, we aimed to compare the effect of of three sitting
      positions (the traditional sitting position (TSP), the harmstring stretch position (HSP), and
      the squatting position on the success rate of combined spinal epidural anesthesia in patients
      undergoing total knee arhtoplasty (TKA) or total hip arthroplasty (THA) surgery.
    

Detailed description: 
      Positioning of patients plays a major role to identify accurately epidural and/or spinal
      spaces for neuraxial blocks. Flexed back is considered mandatory to widen the inter spinous
      space in traditional lateral and sitting positions. In traditional sitting position (TSP),
      the patient is positioned in a sitting posture on the operating table. A stool is placed by
      the side of the operating table to support the legs. Both hips and knees are maximally
      flexed.

      In recent years, several studies suggested that the reduction of lumbar lordosis may increase
      the success rate of spinal or epidural block and reduce needle-bone contact. Different
      modified sitting positions were described for this aim: the harmstring stretch position
      (HSP), the squatting position (SP), and the crossed-leg position (CLP).

      In modified sitting positions, the patients sit up from supine position with the legs
      remaining on the operating table, either knees are maximally extended (the harmstring stretch
      position), or hips and knees are maximally flexed (the squatting position), or hips and knees
      are flexed with crossing the legs (the crossed leg position). All studies comparing modified
      sitting positions with TSP found that the success rate and number of needle bone contacts
      were similar except one study which reported a lower needle bone contact with squatting
      position. Other factors contributing the success of the neuraxial block were: anatomical
      landmarks (palpability of the spinous processes, identification of the midline),
      immobilization of the patient during the injection, and the provider's level of experience.

      The combined spinal - epidural (CSE) technique has been increasingly used for over thirty
      years which consist of intentional injection of a local anesthetic into the subarachnoidal
      space and the placement of a catheter into epidural space to prolong or modify the block.

      Although CSE technique combines the best features of spinal and epidural blockade, it is a
      more complicated to perform. Studies comparing CSE with epidural and/or spinal technique
      reported similar failure rates but most of them did not focuse on the effect of patient's
      positioning.

      In this prospective and randomized study, we aimed to compare the effect of of three sitting
      positions (the traditional sitting position (TSP), the harmstring stretch position (HSP), and
      the squatting position (SP) on the success rate of CSE anesthesia in patients undergoing
      total knee arhtoplasty (TKA) or total hip arthroplasty (THA) surgery. The CLSP was not
      included in the study design because the crossing the legs during the procedure seemed to be
      painful and difficult in patients with degenerated knee joints.

      Our primary endpoint was the number of needle bone contact and the secondary endpoint was
      ease of needle insertion/space identification.
    

Intervention name(s): positions of patients for combined spinal-epidural anesthesia; Combined spinal epidural anesthesia
Intervention type(s): Procedure; Procedure
Intervention description(s): Patients in groups will be positioned according to the study groups for performing combined spinal epidural anesthesia.; After positioning, a combined spinal epidural anesthesia (CSE) will be applied using a CSE Tuohy Needle (18 G) and 27 G Whitacre spinal needle via needle - through needle technique. The epidural space will be located with loss of resistance to saline. 3 ml hyperbaric bupivacaine 0.5% (15 mg) will be given for spinal anesthesia after identification of subarachnoidal space.
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: randomized controlled study
Masking: None (Open Label)
Primary purpose: Screening
Keywords: traditional sitting position; combine spinal-epidural anesthesia; orthopedic surgery