Parasacral Sciatic Block Research Articles

Combined paravertebral plexus block and parasacral sciatic block in healthy dogs

ObjectiveTo evaluate the effectiveness of paravertebral lumbar plexus block combined with parasacral sciatic block to anesthetize one hind limb in awake dogs. Study designRandomized, controlled, blinded experimental study. AnimalsEight healthy mongrel dogs weighing 12.4 ± 4.5 kg and aged 7 ± 2.33 years. MethodsAfter sedation with medetomidine, dogs received B1: bupivacaine 0.25%, 0.2 mL kg−1, B2: bupivacaine 0.5%, 0.2 mL kg−1, B3: bupivacaine 0.25% 0.4 mL kg−1, P1: NaCl 0.2 mL kg−1, P2: NaCl 0.4 mL kg−1. The lumbosacral plexus was blocked through a paravertebral block of the fourth, fifth and sixth lumbar nerves combined with a parasacral block. The relevant nerves were located using a nerve stimulator and injections of each treatment were administered. Degree and durations of sensory blockade were determined through the response to a Halsted clamp pressure on the skin innervated by the saphenous/femoral and lateral cutaneous femoral nerves (lumbar dermatomes) and by the peroneal and tibial nerves. The degree and duration of motor blockade was assessed evaluating the ability to walk normally and proprioception. ResultsP1 and P2 treatments did not show any grade of sensory or motor blockade. The B2 treatment produced a higher degree of sensory blockade compared to B1 and B3 for both lumbar and sciatic dermatomes. There was no significant difference in the degree of sensory blockade comparing B1 to B3. The B2 treatment had greater motor blockade compared to B1 and B3. The duration of sensory and motor blockade was longer in B2 compared to B1 and B3. Conclusion and clinical relevanceWhen the nerve stimulator is used to perform the lumbosacral plexus block, the concentration of the bupivacaine has a more important role than the volume to produce a more solid and longer block.

485: Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

485: Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

485. Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

485. Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

Epidural Block, Continuous Lumbar Plexus Block, Both Continuous Lumbar Plexus and Parasacral Sciatic Block for Analgesia After Total Hip Arthroplasty

Parasacral Sciatic Nerve Block: Does the Elicited Motor Response Predict the Success Rate?

In this prospective, randomized, double-blind study, we compared the tibial and the peroneal evoked motor response with regard to efficacy of sciatic nerve block using the parasacral approach. Twenty-six ASA I-III patients scheduled for elective lower limb surgery were randomized to receive a parasacral sciatic block, using a nerve stimulator technique seeking either a tibial (n = 14) or peroneal (n = 12) motor response. After the evoked motor response was obtained, a solution of 10 mL 2% lidocaine with epinephrine and 10 mL 0.75% ropivacaine (actual final concentration of epinephrine, 1/160,000) was slowly injected through the needle. Sensory and motor blocks were assessed every 5 min for 30 min by an anesthesiologist blinded to the elicited motor response. If the block was not complete 30 min after injection of the local anesthetics, it was considered as failed, and general anesthesia was supplemented. Time to perform the block and level of minimal and maximal stimulation were not different between groups. The success rate of complete block was significantly higher in the tibial compared to the peroneal group (11 of 14 vs 2 of 12; P = 0.002). Eliciting a tibial motor response predicts a higher success rate than eliciting a peroneal motor response with parasacral sciatic nerve block.