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.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
DIAGNOSTIC
Masking
TRIPLE
Enrollment
98
With the head rotated contralateral to interscalene brachial plexus block (ISBPB), the compactly arranged brachial plexus is visualized lateral to the pulsating subclavian artery under ultrasound guidance. The linear ultrasound transducer is moved cephalad until the C5-to-C8 nerve roots are visualized between the anterior and middle scalene muscles. A block needle is introduced from lateral to medial direction. A nerve root is blocked by placing at least 5 ml of 0.75% ropivacaine around it. The most caudal cervical nerve root (C6 nerve root) is blocked first, and the most cephalad one (C5 nerve root) is blocked last. Then, 3 ml of 0.75% ropivacaine is placed between the scalene and sternocleidomastoid muscles to block the supraclavicular nerves. An equivalent volume of a standard study drug is planned to be used (A total of 25 ml of 0.75% ropivacaine).
With the head rotated contralateral to interscalene brachial plexus block (ISBPB), the compactly arranged brachial plexus is visualized lateral to the pulsating subclavian artery under ultrasound guidance. The linear ultrasound transducer is moved cephalad until the C5-to-C8 nerve roots are visualized between the anterior and middle scalene muscles. A block needle is introduced from lateral to medial direction. A nerve root is blocked by placing at least 5 ml of 0.75% ropivacaine around it. The most caudal cervical nerve root (C8 nerve root) is blocked first, and the most cephalad one (C5 nerve root) is blocked last. Then, 3 ml of 0.75% ropivacaine is placed between the scalene and sternocleidomastoid muscles to block the supraclavicular nerves. An equivalent volume of a standard study drug is planned to be used (A total of 25 ml of 0.75% ropivacaine).
Daegu Catholic University Medical Center
Daegu, South Korea
Time to achieve 50% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 5% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 10% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 90% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 95% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 99% of maximum photoplethysmographic amplitude measured from the 5th finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 5% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 10% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 50% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 90% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 95% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Time to achieve 99% of maximum photoplethysmographic amplitude measured from the 1st finger
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 frame: 25 minutes after the introduction of a block needle
Baseline blood flow measured from the brachial artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 15 minutes before the introduction of a block needle
Baseline blood flow measured from the radial artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 15 minutes before the introduction of a block needle
Baseline blood flow measured from the ulnar artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 15 minutes before the introduction of a block needle
Post-block blood flow measured from the brachial artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 25 minutes after the introduction of a block needle
Post-block blood flow measured from the radial artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 25 minutes after the introduction of a block needle
Post-block blood flow measured from the ulnar artery ipsilateral to interscalene brachial plexus block
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).
Time frame: 25 minutes after the introduction of a block needle
Sensory blockade of the C5 dermatome
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).
Time frame: 30 minutes after the introduction of a block needle
Sensory blockade of the C6 dermatome
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).
Time frame: 30 minutes after the introduction of a block needle
Sensory blockade of the C7 dermatome
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).
Time frame: 30 minutes after the introduction of a block needle
Sensory blockade of the C8 dermatome
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).
Time frame: 30 minutes after the introduction of a block needle
Sensory blockade of the T1 dermatome
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).
Time frame: 30 minutes after the introduction of a block needle
Motor blockade of shoulder abduction
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of elbow flexion
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of forearm supination
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of forearm pronation
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of finger abduction
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of thumb abduction
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of thumb adduction
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 frame: 30 minutes after the introduction of a block needle
Motor blockade of thumb opposition
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 frame: 30 minutes after the introduction of a block needle
Baseline pupil diameter ipsilateral to interscalene brachial plexus block
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.
Time frame: 5 minutes before the introduction of a block needle
Baseline pupil diameter contralateral to interscalene brachial plexus block
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.
Time frame: 5 minutes before the introduction of a block needle
Post-block pupil diameter ipsilateral to interscalene brachial plexus block
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.
Time frame: 35 minutes after the introduction of a block needle
Post-block pupil diameter contralateral to interscalene brachial plexus block
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.
Time frame: 35 minutes after the introduction of a block needle
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)
The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).
Time frame: 1 minute before the surgical incision
Pain upon surgical incision (1.5-3 cm inferior and medial to the posterolateral tip of the acromion)
The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).
Time frame: An average of 1 hour after the introduction of a block needle
Pain upon posterior portal placement (1.5-3 cm inferior and medial to the posterolateral tip of the acromion)
The pain intensity is rated as 0 (no pain), 1 (mild pain), and 2 (severe pain).
Time frame: 1 minute after surgical incision
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