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Assessment of the C8 Dermatomal Block with Photoplethysmographic Amplitude After Interscalene Brachial Plexus Block

Not Applicable
Completed
Conditions
Brachial Plexus Block
Oximetry
Interventions
Procedure: Interscalene brachial plexus block targeting the C5-to-C6 nerve roots
Procedure: Interscalene brachial plexus block targeting the C5-to-C8 nerve roots
Registration Number
NCT06015204
Lead Sponsor
JongHae Kim
Brief Summary

The goal of this clinical trial is to investigate the effectiveness of photoplethysmographic amplitude in assessing the extent of anesthesia in the 8th cervical dermatome in patients undergoing interscalene brachial plexus block (ISBPB). The main question it aims to answer is

* Is there any difference in the post-block changes in photoplethysmographic amplitude measured from the ipsilateral 5th finger (supplied by the 8th cervical nerve root) between ISBPBs targeting the C5-to-C6 nerve roots and the C5-to-C8 nerve roots?

* Do the changes in photoplethysmographic amplitude represent the extent of anesthesia in the 8th cervical dermatome? Participants will receive either ISBPB targeting the C5-to-C6 nerve roots or the C5-to-C8 nerve roots, and then the changes in photoplethysmographic amplitude will be measured from the 5th finger ipsilateral to ISBPB.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
98
Inclusion Criteria
  • American Society of Anesthesiologists physical status 1 or 2
  • Schedule to receive interscalene brachial plexus block for arthroscopic shoulder surgery
Exclusion Criteria
  • Coagulopathy
  • Peripheral vascular diseases
  • Arrhythmias
  • Cardiac conduction abnormalities
  • A history of medication affecting cardiac conduction
  • Ischemic heart disease
  • Hypertension
  • Diabetes mellitus
  • Thyroid dysfunction
  • Other medical conditions affecting autonomic nervous activity
  • Infection at the skin area for interscalene brachial plexus block
  • Peripheral neuropathy or neurologic sequelae in the upper limb ipsilateral to the surgery
  • Allergy to local anesthetics or a history of allergic shock
  • Contralateral vocal cord palsy, hemidiaphragmatic paresis/paralysis or pneumo/hemo thorax
  • Severe restrictive pulmonary disorder
  • Electrolyte imbalance
  • Difficulty in communicating with medical personnel
  • Patients refusal

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
C5-C6 groupInterscalene brachial plexus block targeting the C5-to-C6 nerve rootsThe C5-to-C6 nerve roots and supraclavicular nerves are blocked with 25 ml of 0.75% ropivacaine under ultrasound guidance.
C5-C8 groupInterscalene brachial plexus block targeting the C5-to-C8 nerve rootsThe C5-to-C8 nerve roots and supraclavicular nerves are blocked with 25 ml of 0.75% ropivacaine under ultrasound guidance.
Primary Outcome Measures
NameTimeMethod
Time to achieve 50% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 50% of maximum photoplethysmographic amplitude is achieved, can be derived.

Secondary Outcome Measures
NameTimeMethod
Time to achieve 90% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 90% of maximum photoplethysmographic amplitude is achieved, can be derived.

Sensory blockade of the C7 dermatome30 minutes after the introduction of a block needle

Using an alcohol swab, the sensory blockade of each dermatome is graded as 0 (no cold sensation), 1 (reduced cold sensation), 2 (normal cold sensation).

Motor blockade of elbow flexion30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Time to achieve 5% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 5% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 10% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 10% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 95% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 95% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 90% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 90% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 10% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 10% of maximum photoplethysmographic amplitude is achieved, can be derived.

Baseline blood flow measured from the radial artery ipsilateral to interscalene brachial plexus block15 minutes before the introduction of a block needle

The linear ultrasound transducer is placed parallel with the radial artery at the distal forearm area. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Baseline blood flow measured from the ulnar artery ipsilateral to interscalene brachial plexus block15 minutes before the introduction of a block needle

The linear ultrasound transducer is placed parallel with the ulnar artery at the distal forearm area. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Sensory blockade of the C6 dermatome30 minutes after the introduction of a block needle

Using an alcohol swab, the sensory blockade of each dermatome is graded as 0 (no cold sensation), 1 (reduced cold sensation), 2 (normal cold sensation).

Motor blockade of finger abduction30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Time to achieve 5% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 5% of maximum photoplethysmographic amplitude is achieved, can be derived.

Post-block blood flow measured from the radial artery ipsilateral to interscalene brachial plexus block25 minutes after the introduction of a block needle

The linear ultrasound transducer is placed parallel with the radial artery at the distal forearm area. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Sensory blockade of the C5 dermatome30 minutes after the introduction of a block needle

Using an alcohol swab, the sensory blockade of each dermatome is graded as 0 (no cold sensation), 1 (reduced cold sensation), 2 (normal cold sensation).

Sensory blockade of the C8 dermatome30 minutes after the introduction of a block needle

Using an alcohol swab, the sensory blockade of each dermatome is graded as 0 (no cold sensation), 1 (reduced cold sensation), 2 (normal cold sensation).

Motor blockade of forearm supination30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Motor blockade of thumb adduction30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Post-block pupil diameter ipsilateral to interscalene brachial plexus block35 minutes after the introduction of a block needle

Three minutes after the adaptation in low mesopic conditions, the pupil diameter is measured for 2 seconds at 30 Hz using a portable pupillometer. The pupil diameter is obtained by averaging 60 measurement values.

Pain upon surgical incision (1.5-3 cm inferior and medial to the posterolateral tip of the acromion)An average of 1 hour after the introduction of a block needle

The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).

Time to achieve 99% of maximum photoplethysmographic amplitude measured from the 5th finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 99% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 50% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 50% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 95% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 95% of maximum photoplethysmographic amplitude is achieved, can be derived.

Time to achieve 99% of maximum photoplethysmographic amplitude measured from the 1st finger25 minutes after the introduction of a block needle

During the whole study period, the photoplethysmographic waveform obtained from the 1st and 5th fingers ipsilateral to interscalene brachial plexus block is recorded at 100 Hz. The photoplethysmographic amplitude is calculated by subtracting the valley amplitude from the peak amplitude of one heartbeat in photoplethysmographic waveform. Using all the photoplethysmographic amplitudes between 0 and 25 minutes after the introduction of a block needle, a sigmoid Emax model is built. From the model, the time point, when 99% of maximum photoplethysmographic amplitude is achieved, can be derived.

Post-block blood flow measured from the brachial artery ipsilateral to interscalene brachial plexus block25 minutes after the introduction of a block needle

The linear ultrasound transducer is placed parallel with the brachial artery at the antecubital fossa. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Motor blockade of shoulder abduction30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Motor blockade of forearm pronation30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Baseline pupil diameter ipsilateral to interscalene brachial plexus block5 minutes before the introduction of a block needle

Three minutes after the adaptation in low mesopic conditions, the pupil diameter is measured for 2 seconds at 30 Hz using a portable pupillometer. The pupil diameter is obtained by averaging 60 measurement values.

Baseline blood flow measured from the brachial artery ipsilateral to interscalene brachial plexus block15 minutes before the introduction of a block needle

The linear ultrasound transducer is placed parallel with the brachial artery at the antecubital fossa. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Post-block blood flow measured from the ulnar artery ipsilateral to interscalene brachial plexus block25 minutes after the introduction of a block needle

The linear ultrasound transducer is placed parallel with the ulnar artery at the distal forearm area. Using pulse wave Doppler ultrasound, time velocity integral per heartbeat is calculated. The cross-sectional diameter of the artery is measured with the transducer placed transversely to the artery. The blood flow of the artery (ml/min) is the product of the averaged time velocity integral (cm), cross-sectional area of the artery (cm2), and heart rate (beats/min).

Sensory blockade of the T1 dermatome30 minutes after the introduction of a block needle

Using an alcohol swab, the sensory blockade of each dermatome is graded as 0 (no cold sensation), 1 (reduced cold sensation), 2 (normal cold sensation).

Pain upon posterior portal placement (1.5-3 cm inferior and medial to the posterolateral tip of the acromion)1 minute after surgical incision

The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).

Motor blockade of thumb abduction30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Post-block pupil diameter contralateral to interscalene brachial plexus block35 minutes after the introduction of a block needle

Three minutes after the adaptation in low mesopic conditions, the pupil diameter is measured for 2 seconds at 30 Hz using a portable pupillometer. The pupil diameter is obtained by averaging 60 measurement values.

Motor blockade of thumb opposition30 minutes after the introduction of a block needle

Motor blockade is assessed by rating the force of movement corresponding to each nerve as 0 (complete block), 1 (partial block), or 2 (no block).

Pain upon a pinch at the skin area for posterior portal placement (1.5-3 cm inferior and medial to the posterolateral tip of the acromion)1 minute before the surgical incision

The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).

Baseline pupil diameter contralateral to interscalene brachial plexus block5 minutes before the introduction of a block needle

Three minutes after the adaptation in low mesopic conditions, the pupil diameter is measured for 2 seconds at 30 Hz using a portable pupillometer. The pupil diameter is obtained by averaging 60 measurement values.

Trial Locations

Locations (1)

Daegu Catholic University Medical Center

🇰🇷

Daegu, Korea, Republic of

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