Parasacral Ischial Plane Block in Lower Extremity Surgery

Official title

Evaluation of Sensory and Motor Blockade of Ultrasound-Guided Parasacral Ischial Plane Block in Lower Extremity Surgery

Overview

The parasacral ischial plane block is a novel fascial plane approach targeting the sacral plexus. This technique is technically less challenging and eliminates the requirement for direct visualization of the sacral plexus. The aim of this prospective observational study is to evaluate the efficacy of the conventional sacral plexus block versus the parasacral ischial plane block in patients undergoing lower extremity surgery.

Detailed description

Sympatholysis resulting from central neuraxial block or general anesthesia in lower extremity surgeries may lead to adverse hemodynamic changes and increased perioperative mortality, particularly in high-risk patients. In such patients, lower extremity procedures can be successfully performed solely under sciatic and femoral nerve blocks. Depending on the surgical indication, the sciatic nerve block may be utilized alone or in combination with a lumbar plexus or femoral nerve block.A novel ultrasound-guided (USG) fascial plane approach targeting the sacral plexus, termed the Parasacral Ischial Plane (PIP) block, has been successfully investigated in a limited number of patients. The sacral plexus is located within a fascial plane formed by the pelvic fascia anteriorly, the sacrum medially, the piriformis and gluteus maximus muscles posteriorly, and the ischium bone laterally. The piriformis muscle has no attachment to the ischium; instead, it attaches laterally to the greater trochanter. A fascial plane exists between the piriformis muscle and the ischium, which extends directly to the sacral plexus.

Venkataraju et al. stated that during the demonstration of the PIP block, the needle should be directed and positioned toward the posteromedial surface of the ischium. Following bony contact, the injectate was administered, and its spread was observed beneath the piriformis muscle toward the sacral plexus (SP). This method is considered to be technically more straightforward and carries a lower risk profile.

Interventions

• Procedure Parasacral Ischial Plan Block
  The sacral plexus is located within a fascial plane formed by the pelvic fascia anteriorly, the sacrum medially, the piriformis and gluteus maximus muscles posteriorly, and the ischium laterally. The piriformis muscle has no attachment to the ischium and attaches to the greater trochanter laterally. A fascial plane exists between the piriformis muscle and the ischium; this fascial plane extends to the sacral plexus. Venkataraju et al. stated that in PIP block demonstrations, the needle should b
• Procedure Sacral plexus block
  This block, defined by the parasacral approach, targets the exit point of the plexus at the level of the foramen ischiadicum majus. Unlike distal sciatic blocks, blocking at this level includes the posterior cutaneous femoral nerve, superior/inferior gluteal nerve, and pudendal nerve, along with the ischial nerve. In current practice, ultrasonography (USG) has become the "gold standard"; visualizing the neural structures deep to the piriformis muscle by placing the probe between the lateral sacr

Primary outcome measures

• Sensory and motor block onset time [Time frame: 1 hour]

Secondary outcome measures (1)

• The Numerical Rating Scale (NRS) [Time frame: 1 Day]

Eligibility criteria

Inclusion criteria

• Ages 18-80
• ASA I-III
• Patients operated on under regional anesthesia
• Patients who provided written informed consent
• Patients scheduled for elective lower extremity surgery -

Exclusion criteria

• Patients with a history of allergy to local anesthetic drugs
• Patients with coagulation disorders
• Patients with BMI > 40 kg/m²
• Presence of infection at the block application site
• Chronic pain syndrome (chronic opioid use)
• Pregnant women
• Patients who cannot be communicated with
• Patients requiring emergency surgery -

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Supportive care

Study locations

Turkey (Türkiye) · 1 center

• Bursa High Specialization Training and Research Hospital — Bursa

Publications

• Enneking FK, Chan V, Greger J, Hadzic A, Lang SA, Horlocker TT. Lower-extremity peripheral nerve blockade: essentials of our current understanding. Reg Anesth Pain Med. 2005 Jan-Feb;30(1):4-35. doi: 10.1016/j.rapm.2004.10.002. No abstract available. PMID 15690265
• Zhao J, Huang Y, Fu M, Tao F. Ultrasound-guided suprainguinal fascia iliaca block combined with a sacral plexus block for lower extremity surgery: A case report. Medicine (Baltimore). 2020 Aug 28;99(35):e21921. doi: 10.1097/MD.0000000000021921. PMID 32871928
• Arjun BK, Prijith RS, Sreeraghu GM, Narendrababu MC. Ultrasound-guided popliteal sciatic and adductor canal block for below-knee surgeries in high-risk patients. Indian J Anaesth. 2019 Aug;63(8):635-639. doi: 10.4103/ija.IJA_296_19. PMID 31462809
• Chia N, Low TC, Poon KH. Peripheral nerve blocks for lower limb surgery--a choice anaesthetic technique for patients with a recent myocardial infarction? Singapore Med J. 2002 Nov;43(11):583-6. PMID 12680529
• Bech B, Melchiors J, Borglum J, Jensen K. The successful use of peripheral nerve blocks for femoral amputation. Acta Anaesthesiol Scand. 2009 Feb;53(2):257-60. doi: 10.1111/j.1399-6576.2008.01859.x. PMID 19175579
• Venkataraju A, Narayanan M, Phillips S. Parasacral ischial plane (PIP) block: An easy approach to sacral plexus. J Clin Anesth. 2020 Feb;59:103-105. doi: 10.1016/j.jclinane.2019.06.030. Epub 2019 Jul 16. No abstract available. PMID 31323463

Identifiers

NCT: NCT07594197 · BursaYIERH-AR-ND-01

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗