Comparison of Three Different Sitting Positions for Performing Combined Spinal-Epidural Anesthesia

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.

Condition:

Anesthesia; Adverse Effect, Spinal and Epidural

Treatment:

positions of patients for combined spinal-epidural anesthesia

Start Date:

May 1, 2019

Sponsor:

Diskapi Teaching and Research Hospital

For More Information:

https://clinicaltrials.gov/show/NCT03541798