Axillary approach versus the infraclavicular approach in ultrasound-guided brachial plexus block: comparison of anesthetic time.
ABSTRACT With ultrasound guidance, the success rate of brachial plexus block (BPB) is 95-100% and the anesthetic time has become a more important factor than before. Many investigators have compared ultrasound guidance with the nerve stimulation technique, but there are few studies comparing different approaches via the same ultrasound guidance. We compared the axillary BPB with the infraclavicular BPB under ultrasound guidance.
Twenty-two ASA physical status I-II patients presenting with elective forearm surgery were prospectively randomized to receive an axillary BPB (group AX) or an infraclavicular BPB (group IC) with ultrasound guidance. Both groups received a total of 20 ml of 1.5% lidocaine with 5 µg/ml epinephrine and 0.1 mEq/ml sodium bicarbonate. Patients were then evaluated for block onset and block performance time was also recorded.
Group IC demonstrated a reduction in performance time vs. group AX (622 ± 139 sec vs. 789 ± 131 sec, P < 0.05). But, the onset time was longer in group IC than in group AX (7.7 ± 8.8 min vs. 1.4 ± 2.3 min, P < 0.05). All blocks were successful in both groups.
Under ultrasound guidance, infraclavicular BPB was faster to perform than the axillary approach. But the block onset was slower with the infraclavicular approach.
- [show abstract] [hide abstract]
ABSTRACT: Most upper arm regional anesthesia techniques are successful and differences in efficacy should not dictate the choice of technique. In the present study, we compared humeral block (HB) and infraclavicular brachial plexus block (ICB) using anesthetic time (i.e., duration of the procedure + onset time) as the primary outcome measure. The block was successful when a complete sensory block was obtained in the four major nerves of the arm, and the time to complete block was recorded. Patients undergoing orthopedic surgery of the upper limb were included in a prospective randomized study and received ICB (group I, n = 60 patients) or HB (group H, n = 60 patients). Total anesthetic time was 19.5 min (95% confidence interval [CI], 17.4-21.6 min) for ICB and 20.8 min (95% CI, 18.7--22.9 min) for HB (not significant). Time to perform the block was 4.5 min (95% CI, 4-5 min) for ICB and 9.8 min (95% CI, 8.9--10.7 min) for HB (P < 0.05). The onset time was 15 min (95% CI, 13-17 min) for ICB and 11 min (95% CI, 9--13 min) for HB (P < 0.05). The success rate was 92% for ICB and 95% for HB (not significant). One self-limited vascular puncture was made in each group. HB had a faster onset time but ICB using a double-stimulation technique was faster to perform. Anesthetic time was similar with the two techniques. IMPLICATIONS: We have compared infraclavicular brachial plexus block (ICB) with humeral block. Efficacy and anesthetic time were not significantly different, although time to perform the block was shorter with the ICB.Anesthesia & Analgesia 10/2005; 101(4):1198-201, table of contents. · 3.30 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: We prospectively studied 40 patients (ASA grades I-III) undergoing surgery of the forearm and hand, to investigate the use of ultrasonic cannula guidance for supraclavicular brachial plexus block and its effect on success rate and frequency of complications. Patients were randomized into Group S (supraclavicular paravascular approach; n = 20) and Group A (axillary approach; n = 20). Ultrasonographic study of the plexus sheath was done. After visualization of the anatomy, the plexus sheath was penetrated using a 24-gauge cannula. Plexus block was performed using 30 mL bupivacaine 0.5%. Onset of sensory and motor block of the radial, ulnar, and median nerves was recorded in 10-min intervals for 1 h. Satisfactory surgical anesthesia was attained in 95% of both groups. In Group A, 25% showed an incomplete sensory block of the musculocutaneous nerve, whereas all patients in Group S had a block of this nerve. Complete sensory block of the radial, median, and ulnar nerves was attained after an average of 40 min without a significant difference between the two groups. Because of the direct ultrasonic view of the cervical pleura, we had no cases of pneumothorax. An accidental puncture of subclavian or axillary vessels, as well as neurologic damage, was avoided in all cases. An ultrasonography-guided approach for supraclavicular block combines the safety of axillary block with the larger extent of block of the supraclavicular approach.Anesthesia & Analgesia 04/1994; 78(3):507-13. · 3.30 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: This prospective, randomized, observer-blinded study compared ultrasound-guided supraclavicular (SCB), infraclavicular (ICB), and axillary (AXB) brachial plexus blocks for upper extremity surgery of the elbow, forearm, wrist, and hand. One hundred twenty patients were randomly allocated to receive an ultrasound-guided SCB (n = 40), ICB (n = 40), or AXB (n = 40). Performance time (defined as the sum of imaging and needling times) and the number of needle passes were recorded during the performance of the block. Subsequently, a blinded observer recorded the onset time, block-related pain scores, success rate (surgical anesthesia), and the incidence of complications. The main outcome variable was the total anesthesia-related time, defined as the sum of performance and onset times. No differences were observed between the 3 groups in terms of total anesthesia-related time (23.1-25.5 mins), success rate (95%-97.5%), block-related pain scores, vascular puncture, and paresthesia. Compared with the supraclavicular and infraclavicular approaches, ultrasound-guided AXBs required a higher number of needle passes (6.1 [SD, 2.0] vs 2.0-2.6 [SD, 1.1-1.8]; both P < or = 0.001), a longer needling time (7.4 mins [SD, 2.2 mins] vs 4.9-5.5 mins [SD, 1.9-4.2 mins]; both P < or = 0.016), and a longer performance time (8.5 mins [SD, 2.3 mins] vs 6.0-6.2 mins [SD, 2.1-4.5 mins]; both P < or = 0.008). Supraclavicular blocks resulted in a higher rate of Horner syndrome (37.5% vs 0%-5%; both P < 0.001). Adjunctive ultrasonography results in similar success rates, total anesthesia-related times, and block-related pain scores for the SCB, ICB, and AXB.Regional anesthesia and pain medicine 08/2009; 34(4):366-71. · 4.16 Impact Factor
Korean J Anesthesiol 2011 July 61(1): 12-18
Clinical Research Article
Copyright ⓒ the Korean Society of Anesthesiologists, 2011
Background: With ultrasound guidance, the success rate of brachial plexus block (BPB) is 95-100% and the
anesthetic time has become a more important factor than before. Many investigators have compared ultrasound
guidance with the nerve stimulation technique, but there are few studies comparing different approaches via the
same ultrasound guidance. We compared the axillary BPB with the infraclavicular BPB under ultrasound guidance.
Methods: Twenty-two ASA physical status I-II patients presenting with elective forearm surgery were prospectively
randomized to receive an axillary BPB (group AX) or an infraclavicular BPB (group IC) with ultrasound guidance.
Both groups received a total of 20 ml of 1.5% lidocaine with 5 μg/ml epinephrine and 0.1 mEq/ml sodium
bicarbonate. Patients were then evaluated for block onset and block performance time was also recorded.
Results: Group IC demonstrated a reduction in performance time vs. group AX (622 ± 139 sec vs. 789 ± 131 sec, P <
0.05). But, the onset time was longer in group IC than in group AX (7.7 ± 8.8 min vs. 1.4 ± 2.3 min, P < 0.05). All blocks
were successful in both groups.
Conclusions: Under ultrasound guidance, infraclavicular BPB was faster to perform than the axillary approach. But
the block onset was slower with the infraclavicular approach. (Korean J Anesthesiol 2011; 61: 12-18)
Key Words: Brachial plexus, Nerve block, Ultrasound.
Axillary approach versus the infraclavicular approach in
ultrasound-guided brachial plexus block: comparison of
In Ae Song1, Nam-Su Gil2, Eun-young Choi3, Sung-Eun Sim2, Seong-Won Min2, Young-Jin Ro4, and
Chong Soo Kim2
Department of Anesthesiology and Pain Medicine, 1Seoul National University Bundang Hospital, 2Boramae Municipal Hospital,
3Seoul National University Hospital, Seoul National University College of Medicine, 4Asan Medical Center, University of Ulsan College
of Medicine, Seoul, Korea
Received: November 4, 2010. Revised: 1st, November 25, 2010; 2nd, February 18, 2011. Accepted: February 24, 2011.
Corresponding author: Chong Soo Kim, M.D., Department of Anesthesiology and Pain Medicine, Boramae Municipal Hospital, 39, Boramae-
gil, Dongjak-gu, Seoul 156-707, Korea. Tel: 82-2-870-2511, Fax: 82-2-846-2985, E-mail: firstname.lastname@example.org
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://
creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium,
provided the original work is properly cited.
Korean J Anesthesiol
Song, et al.
The brachial plexus block (BPB) is routinely performed
since it is as effective as general anesthesia in anesthetizing
the upper limbs and is less invasive. As with other areas in
medicine, the technique for the BPB has been improved upon
by the development of medical technology. Early on, local
anesthesia was injected in an area near on the axillary artery
or by paresthesia experienced by the patient. However, with
the introduction of a nerve stimulator, the previous non-visual
approach was technologically advanced. Now, anestheologists
did not have to rely on subjective symptoms given by the patient
and they can objectively use signals from muscle contractions
to perform blocks. Recently, as ultrasound equipment became
widely available, the use of the equipment for nerve blocks
became easier for anesthetists and the non-visual method
performed in nerve blocks developed into a visual method.
Similar to the nerve stimulator guided technique, an
ultrasound-guided BPB can be performed in various places
such as the axillar, supraclavicular, infraclavicular, and
interscalene areas. There have been many reports comparing
various methods for nerve stimulator guided technique [1,2].
However, there are few reports regarding techniques using the
ultrasound-guided method. Many researchers have compared
the ultrasound-guided technique to the nerve stimulator guided
technique, but there are not many comparative studies between
the various methods for ultrasound-guided nerve blocks [3,4].
When comparing the methods for the BPB, the success rate
has been reported as the most important indicator. However,
with the introduction of the ultrasound-guided technique,
the success rate has reached 95-100% [5,6]. Therefore, a
different indicator is required in comparative studies today,
and the anesthetic time is considered as an important
indicator after the success rate . When the anesthetic time
is delayed, the turnover ratio of operating rooms decreases
and the inconvenience the patients are subjected to increases.
Anesthetic time is the sum of the performance time and onset
time. Contrary to the onset time, the performance time also
inconveniences the patients. Therefore, the primary aim of this
study was to determine the performance time with the onset
time and anesthetic time being measured at the same time.
A helpful way to reduce performance time is to simplify
the procedure. Ultrasound-guided axillary block requires
two to three needle insertions, whereas ultrasound-guided
infraclavicular block requires only one needle insertion and one
injection of local anesthesia . Hence, the authors conducted
a randomized controlled clinical trial with the hypothesis that
the performance time of an ultrasound-guided infraclavicular
block will be shorter compared to an ultrasound-guided axillary
Meterials and Methods
The study was approved by the institutional review board and
informed consent being obtained after a detailed explanation of
the purpose of the study as well as the risks and complications
of the procedure were explained to the patients. This study
was done on ASA physical status I-II patients between 18-
80 years of age scheduled for forearm surgery at our hospital
from February to May of 2010. Patients with paresthesia or
paresis in an operating upper limb were excluded from the
study. In addition, cases where BPB was refused and cases
where there were constraints in the local area of anesthesia
such as coagulopathy, local infection in the area of the block
and hypersensitivity for local anesthesia were also excluded.
Twenty-two patients were randomized to receive an axillary
BPB (Group AX, n = 11) or an infraclavicular BPB (Group IC, n =
11). Randomization was done using a randomization program
on the Internet (http://www.randomization.com/).
Without any premedication, the patients were transferred
to a room to perform the block (i.e. not the operating room),
and the vitals were monitored by noninvasive blood pressure
monitoring, pulse oximeter, and electrocardiogram. Both
groups underwent ultrasound-guided nerve block using the in-
plane technique and all block procedures were performed by
one researcher. This researcher has done more than 20 cases
each for both the ultrasound-guided axillary approach and the
infraclavicular approach. Both groups received 20 ml of 1.5%
lidocaine with epinephrine (1 : 200,000) and 0.1 mEq/ml of
Patients in Group AX were laid in the supine position with the
arm to be blocked externally rotated more than 90 degrees and
the elbow flexed to expose the armpit. Betadine was applied
to the skin of the armpit and all procedures were done using
sterile technique. A 13-6 MHz probe (SLA, Sonosite, USA)
for ultrasound (MicromaxxⓇ, Sonosite, USA) was positioned
in the axillary crease perpendicular to the axillary artery for
observation of the axillary artery and surrounding structures.
The axillary artery was confirmed with color Doppler image. A
50 mm 22 gauge Sprotte needle (NanolineⓇ, PAJUNK, Germany)
was inserted using real time ultrasound guidance to infiltrate
the right, left, and back of the axillary artery with anesthetic
medication. First the block needle was inserted in-plane above
the ultrasound probe for injection of 5 ml of the anesthetic to
the back of the axillary artery. Here, it was confirmed that the
block medication did not spread under the triceps fascia behind
the axillary artery. Then, 5 ml of the anesthetic was injected to
the side of the axillary artery. The tip of the needle was inserted
in close proximity to the axillary artery slightly pushing without
puncturing the axillary artery, and the infiltration of the local
anesthesia was confirmed to be spread around the artery and
Ultrasound-guided brachial plexus block
Vol. 61, No. 1, July 2011
not toward the surrounding muscle. Next, the block needle was
removed and re-inserted in-plane below the ultrasound probe
for injection of 5 ml of the anesthetic to the side of the axillary
artery. Finally, the coracobrachialis and biceps were observed
with the ultrasound probe to find the musculocutaneous which
runs between the coracobrachialis or coracobrachialis and
biceps. Then 5 ml of anesthetic was infiltrated around the nerve.
While performing the axillary approach, the block needle was
inserted into the skin twice during the infiltration around the
axillary artery and once for blocking of the musculocutaneous (a
total of three injections).
The patients in Group IC were laid in a supine position with
their arms beside their body with only the head turned toward
the opposite direction of the block area. Betadine was applied
to the skin on the infraclavicular area and all procedures were
performed using sterile technique. The axillary artery was
found using the 13-6 MHz ultrasound probe (SLA, Sonosite,
USA) in the infraclavicular fossa and the probe was positioned
perpendicular to the axillary artery. The artery was confirmed
using color Doppler, and after local anesthesia, an 80 mm
18 gauge Tuohy needle (PericanⓇ, B. Braun, Germany) was
inserted above the ultrasound probe. The needle tip was
positioned at the bottom of the axillary artery (patient’s back
area) and 2 ml of anesthetic was injected. After confirming the
“double bubble sign” where hypoechoic bubbles appear due to
the medication, the remaining 18 ml was injected .
The duration of each procedure was measured from the time
the Betadine was applied to the skin to the end of the infiltration
of the anesthetic, including the removal of the block needle.
The nerve block of the patient was evaluated immediately
after the block procedure and at 5, 10, 15, 20, and 30 minutes
afterwards. The sensory nerves were assessed by alcohol swab
testing the radial nerve (posterior part of wrist and of the three
first fingers), median nerve (anterior part of wrist and of the
three first fingers), ulnar nerve (medial part of wrist and of
the hand), musculocutaneous nerve (lateral part of forearm),
axillary nerve (shoulder), medial brachial nerve (medial part of
arm) and medial antebrachial nerve (medial part of forearm):
responses were compared with the opposite corresponding
areas. No sensation was recorded as 0; hypothesia was recorded
as 1, and normal sensation was recorded as 2. In this method,
when hypoesthesia occurred in the radial, median, ulnar
and musculocutaneous nerves, this was defined as the start
of the nerve block onset time. Regarding motor nerves, the
radial (elbow extension), median (third finger flexion), ulnar
(fifth finger flexion), musculocutaneous (elbow flexion) and
axillary nerves (arm abduction) were assessed with normal
muscle power recorded as 5; slightly reduced power recorded
as 4; significant reduction in power recorded as 3; unable to
move against gravity or only contract the muscles recorded as
2, and complete paralysis was recorded as 1. The nerve block
onset time of the motor nerves was defined as when the radial,
median, ulnar, and musculocutaneous nerves scored lower
than 3. In the case when there was no onset of nerve block 30
minutes after the procedure, it was considered as a block failure
and an additional block was performed. In addition, cases
where general anesthesia was administered due to pain during
surgery were also recorded as a block failure. The occurrence of
complications such as hemorrhage, hematoma, pneumothorax,
and intravascular injection were also recorded.
Using the results from an existing study that compared
ultrasound-guided infraclavicular block to nerve stimulator
guided axillary block, the sample size necessary for a 0.8
statistical power and 0.05 type I error was calculated to be 11
per group . In the statistical analysis, the continuous variable
was expressed as the mean ± standard deviation and a Student’s
t-test was used for the analysis. The categorical variables were
analyzed using a Fisher’s exact test. SPSS (ver 12.0, SPSS Inc,
USA) was used as the statistics program and differences were
considered statistically significant when the P value was less
There were no significant differences between the groups for
age, sex, height, weight and physical status (Table 1). The block
was successful in all patients for both groups so there were
no cases needing an additional block or general anesthesia.
Hypoesthesia in the axillary nerve occurred in 2 patients (18%)
in Group AX and in 9 patients (82%) in Group IC. The duration
of the block procedure was notably shorter for Group IC (622 ±
139 sec) compared to Group AX (789 ± 131 sec) (P < 0.05, Fig. 1).
On the contrary, the onset time of the block was notably faster
for Group AX (1.4 ± 2.3 min) than for Group IC (7.7 ± 8.8 min)
(P < 0.05). As a result, there were no significant differences
between the two groups (Group AX, 870 ± 193 sec vs. Group IC
1,085 ± 526 sec) for the total anesthetic time which included the
performance time and the onset time.
Table 1. Demographic Data
(n = 11)
(n = 11)
ASA physical status (I/II)
49.5 ± 17.5
72.1 ± 12.5
166.2 ± 10.4
37.9 ± 17.6
64.2 ± 13.0
166.8 ± 9.0
Data are expressed as means ± SD or number of patients. AX: axillary
approach, IC: infraclavicular approach, ASA: American Society of
Korean J Anesthesiol
Song, et al.
Fig. 1. Total anesthetic time, onset and procedure duration of the
axillary approach (AX) and the infraclavicular approach (IC). Total
anesthetic time is the sum of the onset and the procedure duration.
The procedure duration was significantly shorter in the IC group.
The onset is significantly shorter in AX group. As a result, the total
anesthetic time was similar between two groups. NS: not significant.
*P < 0.05.
Fig. 2 and 3 compare the onset of the sensory block or motor
block in patients according to each time bracket. Although a
higher rate was consistently seen for patients in Group AX with
the sensory block and for patients in Group IC with the motor
block excluding the musculocutaneous nerve, there were no
significant differences other than in the radial sensory nerve
immediately after the block (Fig. 2A). The ratio of Group AX
patients with a motor block of the musculocutaneous nerve
was higher and there was a significant difference immediately
after and 5 minutes after the block (Fig. 3D). There were no
complications of hemorrhage, hematoma, pneumothorax, or
intravascular injection for both groups.
Results of this prospective randomized comparative study,
demonstrated that ultrasound-guided infraclavicular BPB had a
shorter anesthetic performance time than the axillary approach.
Fig. 2. Percentage of patients with sensory block (score of 1-0) according to the time of cutaneous distribution of: (A) the radial nerve, (B) the
median nerve, (C) the ulnar nerve and (D) the musculocutaneous nerve. Significantly more patients showed sensory block of the radial nerve
in the AX group immediately after block procedure. AX: Axillary approach group, IC: Infraclavicular approach group. Sensory score: 0, no
sensation; 1, hypoesthesia; 2, normal sensation. *P < 0.05 compared with IC group.
Ultrasound-guided brachial plexus block
Vol. 61, No. 1, July 2011
Since there were no block failures in both groups, there were
no differences found in the success rate. The difference in the
performance time was because the infraclavicular approach
required only one injection of local anesthetic while the axillary
approach requires three around the axillary nerve and one in
the musculocutaneous nerve area for a total of four injections.
In our study, there was approximately a 3 minute difference in
the performance time and this reduction in the performance
time is more convenience and comfortable for the patient
who needs to be under a drape for the procedure. Moreover,
a reduction in the performance time also provides time for
the anesthetist to focus on the patient and other matters. In
contrast to the performance time, the onset time of the infra-
clavicular approach appeared to be longer. However, there
was no significant difference when the performance time and
onset time were added together for the total anesthetic time.
These results concur with existing research that compared the
infraclavicular approach and the humeral approach using a
nerve stimulator . The reason that the onset time is different
is thought to be that in the axillary approach infiltration of the
local anesthesia is done at the periphery of the nerve while
the infraclavicular approach, local anesthetic is sprayed in
the proximal area of the nerve. In addition, in the axillary
approach, onset may begin during the infiltration process of
the four local anesthetics so the onset time may be recorded
shorter. The longer onset time could be a shortcoming of the
infraclavicular approach, but in actual procedures, preparations
such as draping of the skin can begin after the block has started
to progress, and in orthopedic surgery where infection must be
avoided, it takes a long time to drape and prepare the skin so
the block can progress during this time. In addition to the fact
that the infraclavicular approach only requires one injection
of the local anesthesia, there is also no need to abduct the
patient’s arm. This is very important for patients who cannot
Fig. 3. Percentage of patients with motor block (score of 2-1) according to the time of cutaneous distribution of: (A) the radial nerve, (B) the
median nerve, (C) the ulnar nerve and (D) the musculocutaneous nerve. Significantly more patients showed motor block of musculocutaneous
nerve in the AX group 0 and 5 minutes after block procedure. AX: Axillary approach group, IC: Infraclavicular approach group. Motor score: 1,
complete paralysis; 2, inability to move against gravity; 3, significant muscle strength reduction; 4, slightly reduced muscle strength; 5, normal
muscle strength. *P < 0.05 compared with IC group.