Roderick Finlayson - Academia.edu (original) (raw)

Papers by Roderick Finlayson

Canadian Journal of Anaesthesia, 2008

Purpose: This narrative review summarizes the evidence derived from randomized controlled trials ... more Purpose: This narrative review summarizes the evidence derived from randomized controlled trials (RCTs) offering blinded assessment and sample size justification, in order to determine the benefits associated with adjunctive ultrasonography (US) and stimulating perineural catheters for nerve blocks.

Canadian Journal of Anaesthesia, Jul 1, 2010

Anesthesia and Analgesia, Sep 1, 2008

Ultrasound-guided infraclavicular block can be performed using the double bubble sign. Previously... more Ultrasound-guided infraclavicular block can be performed using the double bubble sign. Previously described, the double bubble sign consists superiorly of the axillary artery (in short axis) superimposed on an inferior bubble created by local anesthetic injection. In this study, we compared this new method of brachial plexus anesthesia to the traditional triple-nerve stimulation axillary block. Seventy patients were randomized to receive a single-injection, ultrasound-guided infraclavicular block using the double bubble sign or a triple-stimulation axillary block. Both methods produced similar success rates (89%-91%). However, infraclavicular blocks were associated with a shorter performance time (3.90 +/- 2.27 vs 8.03 +/- 3.92 min; P < 0.001) and lower block-related pain scores (2.70 +/- 2.02 vs 4.17 +/- 2.57 on a 0-10 scale; P = 0.01). Compared to triple-stimulation axillary block, ultrasound-guided infraclavicular block using the double bubble sign provided a similar efficacy, a shorter performance time and lower procedural pain scores.

Regional anesthesia and pain medicine, 2016

In teaching centers, primary failure of thoracic epidural analgesia can be due to multiple etiolo... more In teaching centers, primary failure of thoracic epidural analgesia can be due to multiple etiologies. In addition to the difficult anatomy of the thoracic spine, the conventional end point-loss-of-resistance-lacks specificity. Furthermore, insufficient training compounds the problem: learning curves are nonexistent, pedagogical requirements are often inadequate, supervisors may be inexperienced, and exposure during residency is decreasing. Any viable solution needs to be multifaceted. Learning curves should be explored to determine the minimal number of blocks required for proficiency. The problem of decreasing caseload can be tackled with epidural simulators to supplement in vivo learning. From a technical standpoint, fluoroscopy and ultrasonography could be used to navigate the complex anatomy of the thoracic spine. Finally, correct identification of the thoracic epidural space should be confirmed with objective, real-time modalities such as neurostimulation and waveform analysis.

Regional Anesthesia and Pain Medicine, 2016

This multicenter, randomized trial compared intravenous (IV) and perineural (PN) dexamethasone fo... more This multicenter, randomized trial compared intravenous (IV) and perineural (PN) dexamethasone for ultrasound (US)-guided infraclavicular brachial plexus block. Our research hypothesis was both modalities would result in similar durations of motor block. One hundred fifty patients undergoing upper limb surgery with US-guided infraclavicular block were randomly allocated to receive IV or PN dexamethasone (5 mg). The local anesthetic agent (35 mL of lidocaine 1%-bupivacaine 0.25% with epinephrine 5 μg/mL) was identical in all subjects. Patients and operators were blinded to the nature of IV and PN injectates. During the performance of the block, the performance time, number of needle passes, procedural pain, and complications (vascular puncture, paresthesia) were recorded.Subsequently, a blinded observer assessed the success rate (defined as a minimal sensorimotor composite score of 14 of 16 points at 30 minutes), onset time as well as the incidence of surgical anesthesia (defined as the ability to complete surgery without local infiltration, supplemental blocks, IV opioids, or general anesthesia). Postoperatively (at 24 hours), the blinded observer contacted patients with successful blocks to enquire about the duration of motor block, sensory block, and postoperative analgesia. The main outcome variable was the duration of motor block. No intergroup differences were observed in terms of technical execution (performance time/number of needle passes/procedural pain/complications), onset time, success rate, and surgical anesthesia. However, compared to its IV counterpart, PN dexamethasone provided 19% to 22% longer durations for motor block (15.7 ± 6.2 vs 12.9 ± 5.5 hours; P = 0.009), sensory block (16.8 ± 4.4 vs 13.9 ± 5.4 hours; P = 0.002), and postoperative analgesia (22.1 ± 8.5 vs 18.6 ± 6.7 hours; P = 0.014). Compared with its IV counterpart, PN dexamethasone (5 mg) provides a longer duration of motor block, sensory block, and postoperative analgesia for US-guided infraclavicular block. Future dose-finding studies are required to elucidate the optimal dose of dexamethasone.

Regional Anesthesia and Pain Medicine, 2016

Compared with the thoracic and lumbar spine, transforaminal epidural injections and medial branch... more Compared with the thoracic and lumbar spine, transforaminal epidural injections and medial branch blocks in the cervical spine are associated with a higher incidence of neurological complications. Accidental breach of small periforaminal arteries has been implicated in many instances. In this observational study, using ultrasonography, we surveyed the incidence of periforaminal bloods vessels in the cervical spine. Patients undergoing ultrasound-guided cervical medial branch blocks were scanned using color power and pulsed wave Doppler. Five levels from C2/C3 to C6/C7 were studied. Incidental blood vessels located between the anterior tubercles of the transverses process and the posterior borders of the articular pillars were included for analysis. We recorded the diameter and position of arteries relative to contiguous bony landmarks as well the number of veins. In 102 patients, we performed a total 201 scans (1005 cervical levels). Of the 363 incidental vessels identified, 238 were arteries (mean diameter, 1.25 ± 0.45 mm). The latter were most commonly found at the posterior foraminal aspects of C5, C6, and C7 (13%, 11%, and 16% of scans, respectively); the transverse processes of C5 and C6 (10% and 16% of scans, respectively); and the articular pillars of C6 and C7 (19% and 16% of scans, respectively). Small periforaminal arteries are prevalent along the lateral aspect of the cervical spine, adjacent to areas commonly targeted by nerve block procedures. Further trials are required to determine if ultrasound guidance can reduce the incidence of complications related to accidental vascular breach.

Canadian Journal of Anaesthesia, Dec 1, 2007

The purpose of this narrative review is to summarize the evidence derived from randomized control... more The purpose of this narrative review is to summarize the evidence derived from randomized controlled trials (RCTs) regarding approaches and techniques for lower extremity nerve blocks. Using the MEDLINE (January 1966 to April 2007) and EMBASE (January 1980 to April 2007) databases, medical subject heading (MeSH) terms "lumbosacral plexus", "femoral nerve", "obturator nerve", "saphenous nerve", "sciatic nerve", "peroneal nerve" and "tibial nerve" were searched and combined with the MESH term "nerve block" using the operator "and". Keywords "lumbar plexus", "psoas compartment", "psoas sheath", "sacral plexus", "fascia iliaca", "three-in-one", "3-in-1", "lateral femoral cutaneous", "posterior femoral cutaneous", "ankle" and "ankle block" were also queried and combined with the MESH term "nerve block". The search was limited to RCTs involving human subjects and published in the English language. Forty-six RCTs were identified. Compared to its anterior counterpart (3-in-1 block), the posterior approach to the lumbar plexus is more reliable when anesthesia of the obturator nerve is required. The fascia iliaca compartment block may also represent a better alternative than the 3-in-1 block because of improved efficacy and efficiency (quicker performance time, lower cost). For blockade of the sciatic nerve, the classic transgluteal approach constitutes a reliable method. Due to a potentially shorter time for sciatic nerve electrolocation and catheter placement than for the transgluteal approach, the subgluteal approach should also be considered. Compared to electrolocation of the peroneal nerve, electrostimulation of the tibial nerve may offer a higher success rate especially with the transgluteal and lateral popliteal approaches. Furthermore, when performing sciatic and femoral blocks with low volumes of local anesthetics, a multiple-injection technique should be used. Published reports of RCTs provide evidence to formulate limited recommendations regarding optimal approaches and techniques for lower limb anesthesia. Further well-designed and meticulously executed RCTs are warranted, particularly in light of new techniques involving ultrasonographic guidance.

Regional Anesthesia and Pain Medicine, 2015

The epidural space is most commonly identified with loss of resistance (LOR). Although sensitive,... more The epidural space is most commonly identified with loss of resistance (LOR). Although sensitive, LOR lacks specificity, as cysts in interspinous ligaments, gaps in ligamentum flavum, paravertebral muscles, thoracic paravertebral spaces, and intermuscular planes can yield nonepidural LOR. Epidural waveform analysis (EWA) provides a simple confirmatory adjunct for LOR. When the needle is correctly positioned inside the epidural space, measurement of the pressure at its tip results in a pulsatile waveform. In this observational study, we set out to assess the sensitivity, specificity, as well as positive and negative predictive values of EWA for thoracic epidural blocks. We enrolled a convenience sample of 160 patients undergoing thoracic epidural blocks for thoracic surgery, abdominal surgery, or rib fractures. The choice of patient position (sitting or lateral decubitus), approach (midline or paramedian), and LOR medium (air or normal saline) was left to the operator (attending anesthesiologist, fellow, or resident). After obtaining a satisfactory LOR, the operator injected 5 mL of normal saline through the epidural needle. A sterile tubing, connected to a pressure transducer, was attached to the needle to measure the pressure at the needle tip. A 4-mL bolus of lidocaine 2% with epinephrine 5 μg/mL was then administered and, after 10 minutes, the patient was assessed for sensory blockade to ice. The failure rate (incorrect identification of the epidural space with LOR) was 23.1%. Of these 37 failed epidural blocks, 27 provided no sensory anesthesia at 10 minutes. In 10 subjects, the operator was unable to thread the catheter through the needle. When compared with the ice test, the sensitivity, specificity, and positive and negative predictive values of EWA were 91.1%, 83.8%, 94.9%, and 73.8%, respectively. Epidural waveform analysis (with pressure transduction through the needle) provides a simple adjunct to LOR for thoracic epidural blocks. Although its use was devoid of complications, further confirmatory studies are required before its routine implementation in clinical practice.

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2015

This randomized trial aimed to validate a new method for brachial plexus blockade, i.e., targeted... more This randomized trial aimed to validate a new method for brachial plexus blockade, i.e., targeted intracluster injection supraclavicular block (TII SCB), by comparing it with ultrasound-guided axillary block (AXB). We hypothesized that TII SCB would result in a shorter total anesthesia-related time. Forty patients undergoing upper limb surgery were randomized to ultrasound-guided TII SCB (n = 20) or AXB (n = 20). In the TII SCB group, we deposited 16 mL of lidocaine 1.5% with epinephrine 5 µg·mL(-1) into the largest neural cluster (i.e., brachial plexus trunks/divisions). Subsequently, an additional 16 mL was divided into equal aliquots and injected inside each satellite cluster. In the AXB group, 5.5 mL were deposited around the musculocutaneous nerve and 23.5 mL were injected at the 6 o'clock position of the axillary artery. The main outcome for comparison between the two groups was the total anesthesia-related time (defined as the sum of block performance and onset times). We also recorded the number of needle passes, procedural pain, and complications (vascular puncture, paresthesia). The TII SCB method provided a quicker mean (SD) onset time compared with the AXB group [9.5 (5.8) min vs 18.9 (6.1) min; mean difference, -9.5 min; 99% CI, -14.7 to -4.2; P < 0.001] and a shorter mean (SD) total anesthesia-related time [20.1 (5.0) min vs 27.2 (6.5) min; mean difference, -7.0 min; 95% CI, -10.9 to -3.1; P = 0.001]. There were no intergroup differences in terms of success rate (95%), procedural pain, vascular puncture and paresthesia. The AXB group displayed a faster performance time [8.2 (1.6) min vs 10.6 (2.6) min; P = 0.001] with fewer median [interquartile range] needle passes (3 [2-6] vs 5 [4-8]; P < 0.001). Ultrasound-guided TII SCB provides a quicker onset and a shorter total anesthesia-related time than ultrasound-guided AXB.

Regional Anesthesia and Pain Medicine, 2010

Advances in Anesthesia, 2013

By enabling operators to visualize the nerve, needle, and spread of local anesthetic agents, ultr... more By enabling operators to visualize the nerve, needle, and spread of local anesthetic agents, ultrasound guidance has revolutionized the practice of regional anesthesia. In recent years, several review articles have outlined the benefits Keywords Ultrasonography Paresthesia Peripheral nerve stimulation Intraneural injection

PM & R : the journal of injury, function, and rehabilitation, Jan 12, 2015

We describe a case of a 53-year-old man with type 2 diabetes mellitus in whom cervical-radiculopl... more We describe a case of a 53-year-old man with type 2 diabetes mellitus in whom cervical-radiculoplexus neuropathy developed, with concomitant cranial and phrenic nerve involvement, occurring as a stepwise, monophasic course. The patient had a presumed remote history of idiopathic cervical-radiculoplexus neuropathy.

Regional Anesthesia and Pain Medicine, 2015

This prospective randomized trial compared ultrasound-guided single-injection (SI) and triple-inj... more This prospective randomized trial compared ultrasound-guided single-injection (SI) and triple-injection (TI) subparaneural popliteal sciatic nerve block. We hypothesized that multiple injections are not required when local anesthetic (LA) is deposited under the paraneurium because the latter entraps LA molecules, ensuring circumferential spread around the nerve. Therefore, in addition to comparable success rates, we also expected similar total anesthesia-related times (sum of performance and onset times) and designed this study as an equivalency trial. Ultrasound-guided subparaneural posterior popliteal sciatic nerve block was carried out in 100 patients. In the SI group, LA was deposited at a single location between the tibial and peroneal nerves. In the TI group, LA was injected between the tibial and peroneal divisions, medial to the tibial nerve, and lateral to the common peroneal nerve. The total LA volume (15 mL) and mixture (lidocaine 1%-bupivacaine 0.25%-epinephrine 5 μg/mL) were identical in all subjects. The performance time, number of needle passes, and adverse events (paresthesia, neural edema) were recorded by the (nonblinded) investigator supervising the block. A blinded observer evaluated the success rate (sensorimotor composite score ≥6/8 points at 30 minutes) as well as the onset time and contacted patients 7 days after the surgery to inquire about persistent numbness or motor deficit. Both techniques provided comparable success rates (92%) and total anesthesia-related times (17.1-19.7 minutes). Expectedly, the SI group required fewer needle passes (1 vs 3; P < 0.001) and a shorter needling time (3.0 ± 2.3 minutes vs 4.0 ± 2.3 minutes; P = 0.025). The TI group displayed a shorter onset time (12.5 ± 7.9 minutes vs 15.8 ± 7.9 minutes; P = 0.027). The performance time, procedural discomfort, and incidence of paresthesia (14%-20%) were similar between the 2 groups. Sonographic neural swelling was detected in 2 subjects in the SI group. In both cases, the needle was carefully withdrawn and the injection was completed uneventfully. Follow-up of the 100 subjects 1 week after surgery revealed no residual numbness or motor deficit. Ultrasound-guided SI and TI subparaneural popliteal sciatic nerve blocks result in comparable success rates and total anesthesia-related times. Expectedly, the SI technique requires fewer needle passes.

Canadian Journal of Anaesthesia, 2008

Purpose: This narrative review summarizes the evidence derived from randomized controlled trials ... more Purpose: This narrative review summarizes the evidence derived from randomized controlled trials (RCTs) offering blinded assessment and sample size justification, in order to determine the benefits associated with adjunctive ultrasonography (US) and stimulating perineural catheters for nerve blocks.

Canadian Journal of Anaesthesia, Jul 1, 2010

Anesthesia and Analgesia, Sep 1, 2008

Ultrasound-guided infraclavicular block can be performed using the double bubble sign. Previously... more Ultrasound-guided infraclavicular block can be performed using the double bubble sign. Previously described, the double bubble sign consists superiorly of the axillary artery (in short axis) superimposed on an inferior bubble created by local anesthetic injection. In this study, we compared this new method of brachial plexus anesthesia to the traditional triple-nerve stimulation axillary block. Seventy patients were randomized to receive a single-injection, ultrasound-guided infraclavicular block using the double bubble sign or a triple-stimulation axillary block. Both methods produced similar success rates (89%-91%). However, infraclavicular blocks were associated with a shorter performance time (3.90 +/- 2.27 vs 8.03 +/- 3.92 min; P < 0.001) and lower block-related pain scores (2.70 +/- 2.02 vs 4.17 +/- 2.57 on a 0-10 scale; P = 0.01). Compared to triple-stimulation axillary block, ultrasound-guided infraclavicular block using the double bubble sign provided a similar efficacy, a shorter performance time and lower procedural pain scores.

Regional anesthesia and pain medicine, 2016

In teaching centers, primary failure of thoracic epidural analgesia can be due to multiple etiolo... more In teaching centers, primary failure of thoracic epidural analgesia can be due to multiple etiologies. In addition to the difficult anatomy of the thoracic spine, the conventional end point-loss-of-resistance-lacks specificity. Furthermore, insufficient training compounds the problem: learning curves are nonexistent, pedagogical requirements are often inadequate, supervisors may be inexperienced, and exposure during residency is decreasing. Any viable solution needs to be multifaceted. Learning curves should be explored to determine the minimal number of blocks required for proficiency. The problem of decreasing caseload can be tackled with epidural simulators to supplement in vivo learning. From a technical standpoint, fluoroscopy and ultrasonography could be used to navigate the complex anatomy of the thoracic spine. Finally, correct identification of the thoracic epidural space should be confirmed with objective, real-time modalities such as neurostimulation and waveform analysis.

Regional Anesthesia and Pain Medicine, 2016

This multicenter, randomized trial compared intravenous (IV) and perineural (PN) dexamethasone fo... more This multicenter, randomized trial compared intravenous (IV) and perineural (PN) dexamethasone for ultrasound (US)-guided infraclavicular brachial plexus block. Our research hypothesis was both modalities would result in similar durations of motor block. One hundred fifty patients undergoing upper limb surgery with US-guided infraclavicular block were randomly allocated to receive IV or PN dexamethasone (5 mg). The local anesthetic agent (35 mL of lidocaine 1%-bupivacaine 0.25% with epinephrine 5 μg/mL) was identical in all subjects. Patients and operators were blinded to the nature of IV and PN injectates. During the performance of the block, the performance time, number of needle passes, procedural pain, and complications (vascular puncture, paresthesia) were recorded.Subsequently, a blinded observer assessed the success rate (defined as a minimal sensorimotor composite score of 14 of 16 points at 30 minutes), onset time as well as the incidence of surgical anesthesia (defined as the ability to complete surgery without local infiltration, supplemental blocks, IV opioids, or general anesthesia). Postoperatively (at 24 hours), the blinded observer contacted patients with successful blocks to enquire about the duration of motor block, sensory block, and postoperative analgesia. The main outcome variable was the duration of motor block. No intergroup differences were observed in terms of technical execution (performance time/number of needle passes/procedural pain/complications), onset time, success rate, and surgical anesthesia. However, compared to its IV counterpart, PN dexamethasone provided 19% to 22% longer durations for motor block (15.7 ± 6.2 vs 12.9 ± 5.5 hours; P = 0.009), sensory block (16.8 ± 4.4 vs 13.9 ± 5.4 hours; P = 0.002), and postoperative analgesia (22.1 ± 8.5 vs 18.6 ± 6.7 hours; P = 0.014). Compared with its IV counterpart, PN dexamethasone (5 mg) provides a longer duration of motor block, sensory block, and postoperative analgesia for US-guided infraclavicular block. Future dose-finding studies are required to elucidate the optimal dose of dexamethasone.

Regional Anesthesia and Pain Medicine, 2016

Compared with the thoracic and lumbar spine, transforaminal epidural injections and medial branch... more Compared with the thoracic and lumbar spine, transforaminal epidural injections and medial branch blocks in the cervical spine are associated with a higher incidence of neurological complications. Accidental breach of small periforaminal arteries has been implicated in many instances. In this observational study, using ultrasonography, we surveyed the incidence of periforaminal bloods vessels in the cervical spine. Patients undergoing ultrasound-guided cervical medial branch blocks were scanned using color power and pulsed wave Doppler. Five levels from C2/C3 to C6/C7 were studied. Incidental blood vessels located between the anterior tubercles of the transverses process and the posterior borders of the articular pillars were included for analysis. We recorded the diameter and position of arteries relative to contiguous bony landmarks as well the number of veins. In 102 patients, we performed a total 201 scans (1005 cervical levels). Of the 363 incidental vessels identified, 238 were arteries (mean diameter, 1.25 ± 0.45 mm). The latter were most commonly found at the posterior foraminal aspects of C5, C6, and C7 (13%, 11%, and 16% of scans, respectively); the transverse processes of C5 and C6 (10% and 16% of scans, respectively); and the articular pillars of C6 and C7 (19% and 16% of scans, respectively). Small periforaminal arteries are prevalent along the lateral aspect of the cervical spine, adjacent to areas commonly targeted by nerve block procedures. Further trials are required to determine if ultrasound guidance can reduce the incidence of complications related to accidental vascular breach.

Canadian Journal of Anaesthesia, Dec 1, 2007

The purpose of this narrative review is to summarize the evidence derived from randomized control... more The purpose of this narrative review is to summarize the evidence derived from randomized controlled trials (RCTs) regarding approaches and techniques for lower extremity nerve blocks. Using the MEDLINE (January 1966 to April 2007) and EMBASE (January 1980 to April 2007) databases, medical subject heading (MeSH) terms "lumbosacral plexus", "femoral nerve", "obturator nerve", "saphenous nerve", "sciatic nerve", "peroneal nerve" and "tibial nerve" were searched and combined with the MESH term "nerve block" using the operator "and". Keywords "lumbar plexus", "psoas compartment", "psoas sheath", "sacral plexus", "fascia iliaca", "three-in-one", "3-in-1", "lateral femoral cutaneous", "posterior femoral cutaneous", "ankle" and "ankle block" were also queried and combined with the MESH term "nerve block". The search was limited to RCTs involving human subjects and published in the English language. Forty-six RCTs were identified. Compared to its anterior counterpart (3-in-1 block), the posterior approach to the lumbar plexus is more reliable when anesthesia of the obturator nerve is required. The fascia iliaca compartment block may also represent a better alternative than the 3-in-1 block because of improved efficacy and efficiency (quicker performance time, lower cost). For blockade of the sciatic nerve, the classic transgluteal approach constitutes a reliable method. Due to a potentially shorter time for sciatic nerve electrolocation and catheter placement than for the transgluteal approach, the subgluteal approach should also be considered. Compared to electrolocation of the peroneal nerve, electrostimulation of the tibial nerve may offer a higher success rate especially with the transgluteal and lateral popliteal approaches. Furthermore, when performing sciatic and femoral blocks with low volumes of local anesthetics, a multiple-injection technique should be used. Published reports of RCTs provide evidence to formulate limited recommendations regarding optimal approaches and techniques for lower limb anesthesia. Further well-designed and meticulously executed RCTs are warranted, particularly in light of new techniques involving ultrasonographic guidance.

Regional Anesthesia and Pain Medicine, 2015

The epidural space is most commonly identified with loss of resistance (LOR). Although sensitive,... more The epidural space is most commonly identified with loss of resistance (LOR). Although sensitive, LOR lacks specificity, as cysts in interspinous ligaments, gaps in ligamentum flavum, paravertebral muscles, thoracic paravertebral spaces, and intermuscular planes can yield nonepidural LOR. Epidural waveform analysis (EWA) provides a simple confirmatory adjunct for LOR. When the needle is correctly positioned inside the epidural space, measurement of the pressure at its tip results in a pulsatile waveform. In this observational study, we set out to assess the sensitivity, specificity, as well as positive and negative predictive values of EWA for thoracic epidural blocks. We enrolled a convenience sample of 160 patients undergoing thoracic epidural blocks for thoracic surgery, abdominal surgery, or rib fractures. The choice of patient position (sitting or lateral decubitus), approach (midline or paramedian), and LOR medium (air or normal saline) was left to the operator (attending anesthesiologist, fellow, or resident). After obtaining a satisfactory LOR, the operator injected 5 mL of normal saline through the epidural needle. A sterile tubing, connected to a pressure transducer, was attached to the needle to measure the pressure at the needle tip. A 4-mL bolus of lidocaine 2% with epinephrine 5 μg/mL was then administered and, after 10 minutes, the patient was assessed for sensory blockade to ice. The failure rate (incorrect identification of the epidural space with LOR) was 23.1%. Of these 37 failed epidural blocks, 27 provided no sensory anesthesia at 10 minutes. In 10 subjects, the operator was unable to thread the catheter through the needle. When compared with the ice test, the sensitivity, specificity, and positive and negative predictive values of EWA were 91.1%, 83.8%, 94.9%, and 73.8%, respectively. Epidural waveform analysis (with pressure transduction through the needle) provides a simple adjunct to LOR for thoracic epidural blocks. Although its use was devoid of complications, further confirmatory studies are required before its routine implementation in clinical practice.

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2015

This randomized trial aimed to validate a new method for brachial plexus blockade, i.e., targeted... more This randomized trial aimed to validate a new method for brachial plexus blockade, i.e., targeted intracluster injection supraclavicular block (TII SCB), by comparing it with ultrasound-guided axillary block (AXB). We hypothesized that TII SCB would result in a shorter total anesthesia-related time. Forty patients undergoing upper limb surgery were randomized to ultrasound-guided TII SCB (n = 20) or AXB (n = 20). In the TII SCB group, we deposited 16 mL of lidocaine 1.5% with epinephrine 5 µg·mL(-1) into the largest neural cluster (i.e., brachial plexus trunks/divisions). Subsequently, an additional 16 mL was divided into equal aliquots and injected inside each satellite cluster. In the AXB group, 5.5 mL were deposited around the musculocutaneous nerve and 23.5 mL were injected at the 6 o'clock position of the axillary artery. The main outcome for comparison between the two groups was the total anesthesia-related time (defined as the sum of block performance and onset times). We also recorded the number of needle passes, procedural pain, and complications (vascular puncture, paresthesia). The TII SCB method provided a quicker mean (SD) onset time compared with the AXB group [9.5 (5.8) min vs 18.9 (6.1) min; mean difference, -9.5 min; 99% CI, -14.7 to -4.2; P < 0.001] and a shorter mean (SD) total anesthesia-related time [20.1 (5.0) min vs 27.2 (6.5) min; mean difference, -7.0 min; 95% CI, -10.9 to -3.1; P = 0.001]. There were no intergroup differences in terms of success rate (95%), procedural pain, vascular puncture and paresthesia. The AXB group displayed a faster performance time [8.2 (1.6) min vs 10.6 (2.6) min; P = 0.001] with fewer median [interquartile range] needle passes (3 [2-6] vs 5 [4-8]; P < 0.001). Ultrasound-guided TII SCB provides a quicker onset and a shorter total anesthesia-related time than ultrasound-guided AXB.

Regional Anesthesia and Pain Medicine, 2010

Advances in Anesthesia, 2013

By enabling operators to visualize the nerve, needle, and spread of local anesthetic agents, ultr... more By enabling operators to visualize the nerve, needle, and spread of local anesthetic agents, ultrasound guidance has revolutionized the practice of regional anesthesia. In recent years, several review articles have outlined the benefits Keywords Ultrasonography Paresthesia Peripheral nerve stimulation Intraneural injection

PM & R : the journal of injury, function, and rehabilitation, Jan 12, 2015

We describe a case of a 53-year-old man with type 2 diabetes mellitus in whom cervical-radiculopl... more We describe a case of a 53-year-old man with type 2 diabetes mellitus in whom cervical-radiculoplexus neuropathy developed, with concomitant cranial and phrenic nerve involvement, occurring as a stepwise, monophasic course. The patient had a presumed remote history of idiopathic cervical-radiculoplexus neuropathy.

Regional Anesthesia and Pain Medicine, 2015

This prospective randomized trial compared ultrasound-guided single-injection (SI) and triple-inj... more This prospective randomized trial compared ultrasound-guided single-injection (SI) and triple-injection (TI) subparaneural popliteal sciatic nerve block. We hypothesized that multiple injections are not required when local anesthetic (LA) is deposited under the paraneurium because the latter entraps LA molecules, ensuring circumferential spread around the nerve. Therefore, in addition to comparable success rates, we also expected similar total anesthesia-related times (sum of performance and onset times) and designed this study as an equivalency trial. Ultrasound-guided subparaneural posterior popliteal sciatic nerve block was carried out in 100 patients. In the SI group, LA was deposited at a single location between the tibial and peroneal nerves. In the TI group, LA was injected between the tibial and peroneal divisions, medial to the tibial nerve, and lateral to the common peroneal nerve. The total LA volume (15 mL) and mixture (lidocaine 1%-bupivacaine 0.25%-epinephrine 5 μg/mL) were identical in all subjects. The performance time, number of needle passes, and adverse events (paresthesia, neural edema) were recorded by the (nonblinded) investigator supervising the block. A blinded observer evaluated the success rate (sensorimotor composite score ≥6/8 points at 30 minutes) as well as the onset time and contacted patients 7 days after the surgery to inquire about persistent numbness or motor deficit. Both techniques provided comparable success rates (92%) and total anesthesia-related times (17.1-19.7 minutes). Expectedly, the SI group required fewer needle passes (1 vs 3; P < 0.001) and a shorter needling time (3.0 ± 2.3 minutes vs 4.0 ± 2.3 minutes; P = 0.025). The TI group displayed a shorter onset time (12.5 ± 7.9 minutes vs 15.8 ± 7.9 minutes; P = 0.027). The performance time, procedural discomfort, and incidence of paresthesia (14%-20%) were similar between the 2 groups. Sonographic neural swelling was detected in 2 subjects in the SI group. In both cases, the needle was carefully withdrawn and the injection was completed uneventfully. Follow-up of the 100 subjects 1 week after surgery revealed no residual numbness or motor deficit. Ultrasound-guided SI and TI subparaneural popliteal sciatic nerve blocks result in comparable success rates and total anesthesia-related times. Expectedly, the SI technique requires fewer needle passes.