Current Intensity for the Obturator Nerve Block (Current_ONB)

Chosun University Hospital

Status: Completed

Conditions: Bladder Tumor

Treatments: Diagnostic Test: Nerve stimulator; Drug: Rocuronium Bromide

Study type: Interventional

Funder types: Other

Identifiers

NCT05872451

ONB

Details and patient eligibility

About

The purpose of the present study was to find out the difference in current intensity required for nerve stimulation according to the presence or absence of neuromuscular blockade during the obturator nerve block procedure for TURP.

Full description

During the transurethral resection of bladder tumors (TURBT) procedure under spinal anesthesia, the obturator nerve block is required to prevent the accidental movement of adductor longus muscles by electrical stimulation. However, during general anesthesia, the contraction of the adductor longus muscle would be lost due to deep neuromuscular blockade. However, some reports showed that the contraction of the adductor longus muscle occurs even in the deep neuromuscular blockade.

The current intensity for the nerve stimulation during nerve block is 0.3--0.5 mA when the needle tip is near the nerve. However, it is still unknown what current intensity is required to show the contraction of the adductor longus muscle when the patient is in a deep neuromuscular blockade.

Therefore, in this study, investigators aimed to determine the difference in current intensity required for nerve stimulation according to the presence or absence of neuromuscular blockade during obturator nerve block for TURP. In addition, investigators aimed to determine that the obturator nerve block is required during the TURP procedure in patients with deep neuromuscular blockade during general anesthesia.

Enrollment: 30 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients undergoing TURP procedure

Exclusion criteria

• Patients with anatomical or functional anomaly in the upper airways
• Patients with neuromuscular disease
• Patients with hip joint disorders
• BMI of < 18.5 or > 30.0 kg/m2

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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30 participants in 1 patient group

Current intensity

Experimental group

Description:

1. An I-gel mask is inserted for the mechanical ventilator of the patient who is sedated with propofol. 2. For the ultrasound-guided obturator nerve (ON) block, and needle tip gradually advanced to the anterior branch of the ON. The current intensity for the stimulation of ON starts at 1.0 mA (using the sequential electrical nerve stimulation mode), and the needle is advanced gradually to the location where the contraction of the adductor longus muscle (ALM) occurs at 0.3-0.5 mA. 3. After fixing the needle in that position, measure the current intensity. 4. Then, rocuronium (0.6 mg/kg) is administered under quantitative neuromuscular-blockade monitoring. 5. When the train-of-four count becomes 0, the current intensity is increased until the contraction of the ALM occurs. 6. The current intensity is measured when the contraction of the ALM occurs.

Treatment:

Drug: Rocuronium Bromide

Diagnostic Test: Nerve stimulator