The efficacy and safety of opioid-free anesthesia combined with ultrasound-guided intermediate cervical plexus block vs. opioid-based anesthesia in thyroid surgery-a randomized controlled trial.

PURPOSE: In the context of the current comfort medicine and enhanced recovery after surgery, there is a demand for a new anesthesia method to reduce adverse reactions and accelerate recovery after surgery. This randomized controlled trial aimed to compare the efficacy and safety between opioid-free anesthesia (OFA) combined with ultrasound-guided intermediate cervical plexus block (ICPB) and opioid-based anesthesia in patients after thyroid surgery. METHODS: In this study, 75 patients scheduled for thyroid surgery under general anesthesia were randomly allocated into two groups. The primary outcome included the incidence of nausea within 24 h after surgery. The main secondary outcomes included the incidence of vomiting and the visual analog score (VAS) scores within 24 h after surgery as well as the quality of recovery 40 questionnaires (QoR-40) scores 24 h after surgery. RESULTS: In the OFA group, the incidence of postoperative nausea was 6.1%, compared to 39.4% in the control group (p = 0.001). No patient presented with postoperative vomiting in the OFA group, while 15.2% of patients suffered from postoperative vomiting in the control group (p = 0.063). The VAS scores of patients in the postanesthetic care unit (PACU) and 2 h, 4 h, and 6 h after surgery were lower in the OFA group, and the difference is statistically significant. Besides, the VAS scores of patients at rest (p = 1.000) and during swallowing (p = 1.000) 24 h after surgery were comparable. CONCLUSION: Compared with opioid-based anesthesia, the OFA combined with the ultrasound-guided ICPB can better improve patients' postoperative recovery, reduce nausea, and decrease pain scores. TRIAL REGISTRATION: Chinese Clinical Trial Regisrty, ChiCTR2200056344, https://www.chictr.org.cn.

Could C3, 4, and 5 Nerve Root Block be a Better Alternative to Interscalene Block Plus Intermediate Cervical Plexus Block for Patients Undergoing Surgery for Midshaft and Medial Clavicle Fractures? A Randomized Controlled Trial.

BACKGROUND: Variable innervation of the clavicle is a major challenge in surgery of clavicle fractures with patients under regional anesthesia. An interscalene block (ISB) combined with an intermediate cervical plexus block (ICPB) provides analgesia in clavicle fracture surgery, but this combination does not completely block sensation in the midshaft or medial clavicle. Cervical nerve root block is an alternative to deep cervical plexus block and has recently been used as an analgesic method in the neck and shoulder. Whether it should be used as an alternative for midshaft and medial clavicle fractures is unknown. QUESTIONS/PURPOSES: In this randomized controlled trial, we compared a C3, 4, and 5 nerve root block to ISB combined with ICPB in surgery of midshaft and medial clavicle fractures in terms of the (1) proportion of patients achieving a sensory block that is sufficient for surgery, (2) onset time and duration of the block, and (3) effectiveness of postoperative analgesia, as measured by pain scores and consumption of analgesics. METHODS: Between November 2021 and December 2021, we treated 154 patients for clavicle fractures. A total of 122 were potentially eligible, 91 of whom agreed to participate in this study. Twenty-nine patients were excluded because the patients chose general anesthesia or declined to undergo surgery. Ultimately, 62 patients were randomly allocated into the C3, 4, and 5 group or ISB + ICPB group, with 31 patients in each group; there were no dropouts. All patients were analyzed in the group they were randomized to under intention-to-treat principles. The assessor and patients were blinded to randomization throughout the trial. The two groups did not differ in any important ways, including age, gender, BMI, American Society of Anesthesiologists classification, and type of clavicle fracture. The two groups received either an ultrasound-guided C3, 4, and 5 nerve root block with 2, 3, and 5 mL of 0.5% ropivacaine or ultrasound-guided ISB with ICPB with 20 mL of 0.5% ropivacaine. The primary outcome was the proportion of patients in each group with a successful nerveba block who did not receive general anesthesia; this was defined as nerve block success. Secondary outcomes included the onset time and duration of the sensory block, defined as the onset to the moment when the patients felt pain and sought rescue analgesia; pain assessment in terms of the numeric rating scale (NRS) score (range 0 to 10) for pain after nerve block before and during surgery; and the median amount of sufentanil consumed intraoperatively and postoperatively in the recovery room. The dosing of sufentanil was determined by the assessor when the NRS score was 1 to 3 points. If the NRS score was more than 3 points, general anesthesia was administered as a rescue method. Complications after the two inventions such as toxic reaction, dyspnea, hoarseness, pneumothorax, and Horner syndrome were also recorded in this study. RESULTS: A higher proportion of patients in the C3, 4, and 5 group had a successful nerve block than in the ISB + ICPB group (97% [30 of 31] versus 68% [21 of 31], risk ratio 6 [95% CI 1.5 to 37]; p < 0.01). The median onset time was 2.5 minutes (range 2.0 to 3.0 minutes) in the C3, 4, and 5 group and 12 minutes (range 9 to 16 minutes) in the ISB + ICPB group (difference of medians 10 minutes; p < 0.001). The sensory block duration was 10 ± 2 hours in the C3, 4, and 5 group and 8 ± 2 hours in the ISB + ICPB group (mean difference 2 hours [95% CI 1 to 3 hours]; p < 0.001). The median sufentanil consumption was lower in the C3, 4, 5 group than in the ISB + ICPB (median 5 µg [range 0.0 to 5.0 µg] versus median 0 µg [range 0.0 to 0.0 µg]; difference of medians 5.0 µg; p < 0.001). There were no differences between the two groups regarding NRS scores after nerve blocks and NRS score for incision and periosteum separation, with the minimum clinically important difference set at a 2-point difference (of 10). There were no severe complications in this study. CONCLUSION: Based on our analysis of the data, a C3, 4, and 5 nerve root block was better than ISB combined with ICPB for surgery to treat medial shaft and medial clavicle fractures. When choosing the anesthesia method, however, the patient's basic physiologic condition and possible complications should be considered. LEVEL OF EVIDENCE: Level I, therapeutic study.

Ultrasound-Guided Clavipectoral Fascial Plane Block With Intermediate Cervical Plexus Block for Midshaft Clavicular Surgery: A Prospective Randomized Controlled Trial.

BACKGROUND: Regional anesthesia such as interscalene brachial plexus block (ISBPB) with intermediate cervical plexus block (ICPB) is generally a preferred choice for clavicular surgery. However, various studies have shown that these blocks, especially ISBPB, could cause phrenic nerve paralysis and decrease diaphragmatic motion. The study aimed to evaluate the efficacy of clavipectoral fascial plane block (CPB), an alternative technique to ISBPB, with ICPB, in reducing hemidiaphragmatic paralysis during midshaft clavicular surgery. METHODS: Forty patients scheduled for right midshaft clavicular surgery were randomized (1:1) into an ultrasound-guided ISBPB with ICPB (BC) group or ultrasound-guided CPB with ICPB (CC) group. Five milliliter of 0.375% ropivacaine was used for ICPB, another 20 mL for ISBPB or CPB, and no administration of additional sedative or general anesthetic was planned. Primary outcome was measured by the incidence of hemidiaphragmatic paralysis using M-mode ultrasonography, while secondary outcomes were measured by bedside pulmonary function test, the success rate of block, the time required for the block procedure and onset of block, and motor block score in right upper extremity. RESULTS: In comparison with BC group, the incidence of hemidiaphragmatic paralysis postblock was decreased in CC group (50% vs 0%; P < .001), and measurement of bedside pulmonary function was significantly improved. There was a 100% success rate for anesthetic block in both BC and CC groups, and CC group showed lower motor block score in upper extremity and less block procedure time than BC group (7.1 ± 1.2 vs 3.2 ± 0.6 minutes; P < .001). Moreover, no significant differences were found between time of onset of block and other anesthetic complications in the 2 groups. CONCLUSIONS: Ultrasound-guided CPB with ICPB could significantly reduce hemidiaphragmatic paralysis and provide an adequate surgical anesthesia with fewer complications such as motor block in upper extremity during right midshaft clavicular surgery.

Aphonia Following Bilateral Cervical Plexus Blocks for an Awake Hemithyroidectomy: A Case Report.

A 35-year-old female patient was scheduled for a left hemithyroidectomy. We performed bilateral cervical plexus blocks with ultrasound guidance for an awake thyroidectomy. Soon after the blocks, she developed a weak voice, which gradually progressed to complete aphonia. Due to her apprehension, general anesthesia was administered. After an uneventful surgery, the patient spontaneously regained her normal voice in the postoperative period. The case report describes a previously unreported complication of aphonia presumably due to bilateral recurrent laryngeal nerve blocks, which might have occurred from the infiltrated local anesthetic extravasating to the deeper planes through the cervical fascia.

Ultrasound-guided interscalene block combined with intermediate or superficial cervical plexus block for clavicle surgery: A randomised double blind study.

BACKGROUND: The complex innervation of the clavicle makes general anaesthesia a preferred technique for clavicular surgeries in current practice. The role and approach of regional anaesthesia remains unanswered. OBJECTIVES: This study aims to delineate the relative effectiveness between interscalene brachial plexus block with either intermediate cervical plexus or superficial cervical plexus block (CPB) as the anaesthetics for clavicular surgery. DESIGN: A randomised, double-blind prospective study. SETTING: Single-centre, tertiary care medical college and research institute. PATIENTS: Fifty patients with American Society of Anesthesiologist's (ASA) grade I to III, aged 18 to 70 years, scheduled for clavicular surgery, during May 2018 to April 2019 were enrolled in this study. INTERVENTION: All patients received interscalene block with 10 ml of 0.5% bupivacaine. Patients were randomised to undergo additional ultrasound-guided intermediate CPB (Group-1) or superficial CPB (Group-2) with 10 ml of 0.5% bupivacaine. MAIN OUTCOME MEASURES: The block success rate, sensory block onset time, haemodynamic parameters, duration of postoperative analgesia and complications were noted. Categorical data were analysed using the chi-square test and Fisher's exact test. Continuous data were analysed using Student's t-test. RESULT: In Group 1, block success was 100%. In Group 2, five patients failed to achieve adequate surgical anaesthesia (P = 0.02). The average sensory block onset time in Group 1 was 2.5 ±â€Š0.4 min and was longer in Group 2, 4.3 ±â€Š0.5 min (P < 0.001). There was no difference between the groups with respect to haemodynamic parameters and complications. The mean duration of postoperative analgesia was longer in Group 1 (7.5 ±â€Š0.8 h) as compared with Group 2 (5.7 ±â€Š0.4 h, P < 0.001). CONCLUSION: Ultrasound-guided combined interscalene and intermediate CPB had a better success rate, with faster sensory block onset time and prolonged postoperative analgesia as compared with interscalene and superficial CPB in patients undergoing clavicle surgery. TRIAL REGISTRATION: Clinical trial registry of India (www.ctri.nic.in) - CTRI/2018/05/013785.

Incidence of hemi-diaphragmatic paresis after ultrasound-guided intermediate cervical plexus block: a prospective observational study.

PURPOSE: An intermediate cervical plexus block (CPB) targets the posterior cervical space between the sternocleidomastoid muscle and the prevertebral fascia. The phrenic nerve descends obliquely on the surface of the anterior scalene muscle beneath the prevertebral fascia after originating from the C3-C5 ventral rami. Therefore, the phrenic nerve can be affected by a local anesthetic during an intermediate CPB, depending on the permeability characteristics of the prevertebral fascia. This study investigated whether an intermediate CPB affects the phrenic nerve, inducing hemidiaphragmatic paresis. METHODS: In this prospective observational study, 20 patients undergoing single-incision transaxillary robot-assisted right thyroidectomy were enrolled. The intermediate CPB (0.25% ropivacaine 0.2 ml/kg) was performed at the C4-5 intervertebral level carefully, without penetrating the prevertebral fascia, before the patient emerged from general anesthesia. Diaphragmatic motions of the block side were measured by M-mode ultrasonography at three time points: before anesthesia (baseline) and at 30 and 60 min after the intermediate CPB. Hemidiaphragmatic paresis was divided into three grades, depending on the percentage of diaphragm movement compared to the baseline: none (> 75%), partial paresis (25-75%), and complete paresis (< 25%). RESULTS: No patient showed any partial or complete ipsilateral hemidiaphragmatic paresis within 60 min after the intermediate CPB. CONCLUSION: Intermediate CPB using 0.2 ml/kg of 0.25% ropivacaine at the C4-5 intervertebral level did not cause ipsilateral hemidiaphragmatic paresis. This may imply that the effect of the intermediate CPB on the phrenic nerve is not significant.

Ultrasound-guided bilateral superficial cervical plexus blocks enhance the quality of recovery in patients undergoing thyroid cancer surgery: A randomized controlled trial.

STUDY OBJECTIVE: Regional anesthesia can improve postoperative analgesia and enhance the quality of recovery (QoR) after surgery. This trial evaluates the effects of ultrasound-guided bilateral superficial cervical plexus block (SCPB) on QoR in patients undergoing thyroid cancer surgery. DESIGN: Prospective, randomized, double-blinded, placebo-controlled trial. SETTING: Operating room. PATIENTS: Seventy-four ASA I-II female patients scheduled for thyroid cancer surgery were included to the study. INTERVENTIONS: Patients were randomly allocated to receive pre-operative ultrasound-guided bilateral SCPB with 10 ml of ropivacaine 0.5% or normal saline on each side. MEASUREMENTS: The primary endpoint was the quality of recovery, which was assessed using the 15-item quality of recovery questionnaire (QoR-15). Secondary endpoints were acute postoperative pain, time to first rescue analgesia, the number of patients requiring rescue analgesia, length of post-anesthesia care unit (PACU) stay, the incidence of postoperative nausea or vomiting (PONV) and dizziness, and patient satisfaction. MAIN RESULTS: The global QoR-15 score at 24 h postoperatively was significantly higher in the SCPB group (Median [IQR], 118 [115-120]) than the control group (110 [106-112]) with a median difference of 8 (95% CI: 6 to 10, P < .001). Compared with the control group, pre-operative ultrasound-guided bilateral SCPB reduced postoperative pain up to 24 h and the incidence of PONV, as well as the length of PACU stay. Additionally, the patient satisfaction scores were improved in the SCPB group (P = .024). CONCLUSION: Pre-operative ultrasound-guided bilateral SCPB with ropivacaine enhances the quality of recovery, postoperative analgesia and patient satisfaction, alleviates the incidence of PONV, and accelerates the PACU discharge following thyroid cancer surgery.

Effects of C8 nerve root block during interscalene brachial plexus block on anesthesia of the posterior shoulder in patients undergoing arthroscopic shoulder surgery: study protocol for a prospective randomized parallel-group controlled trial.

BACKGROUND: A classical approach to produce interscalene brachial plexus block (ISBPB) consistently spares the posterior aspect of the shoulder and ulnar sides of the elbow, forearm, and hand, which are innervated by the lower trunk of the brachial plexus (C8-T1). As an alternative to the classical approach, a caudal approach to ISBPB successfully produces anesthesia of the ulnar sides of the elbow, forearm, and hand. However, its beneficial effects on anesthesia in the posterior aspect of the shoulder have not been investigated. In addition, the C8 nerve root is not routinely selectively blocked during ISBPB. Therefore, we will compare the C5 to C7 and C5 to C8 nerve root blocks during a caudal approach to ISBPB to assess the clinical benefit of C8 nerve blocks for the surgical anesthesia of the posterior aspect of the shoulder. METHODS/DESIGN: In this prospective parallel-group single-blind randomized controlled trial, 74 patients scheduled to undergo arthroscopic shoulder surgery under ISBPB are randomly allocated to receive the C5 to C7 or C5 to C8 nerve root block at a 1:1 ratio. The primary outcome is pain intensity, which is rated as 0 (no pain), 1 (mild pain), or 2 (severe pain), during the introduction of a posterior portal into the glenohumeral joint. The secondary outcomes are (1) the extent of the ipsilateral sensory, motor, hemidiaphragmatic, and stellate ganglion blockade, (2) changes in the results of a pulmonary function test, (3) incidence of complications related to ISBPB, (4) postoperative numerical pain rating scale scores, (5) patients' satisfaction with the ISBPB, (6) dose and frequency of analgesic use, and (7) incidence of conversion to general anesthesia. DISCUSSION: This study is the first to evaluate the beneficial effects of the C8 nerve root block during ISBPB, which has rarely been performed due to the technical challenge in visualizing and blocking the C8 nerve root. It is expected that a C8 nerve root block performed during ISBPB will provide sufficient surgical anesthesia of the posterior aspect of the shoulder, which cannot be achieved by a classical approach to ISBPB. TRIAL REGISTRATION: ClicnicalTrials.gov, NCT03487874 . Registered on 4 April 2018.

[Cervical Plexus Blocks]. / Zervikale Plexusblockaden.

Blockades of the cervical plexus are established anesthesia procedures, not only in the context of operative carotid revascularizations. Recent investigations define inner sonoanatomic landmarks as well as the importance of brain nerves for innervation in the neck region. The present practice-oriented article discusses current study results, alternative techniques (ultrasound- versus landmark-guided) and fields of application (carotid desobliteration, surgery of the shoulder, ear and infraclavicular region).

Analgesic Effects of Ultrasound-Guided Serratus-Intercostal Plane Block and Ultrasound-Guided Intermediate Cervical Plexus Block After Single-Incision Transaxillary Robotic Thyroidectomy: A Prospective, Randomized, Controlled Trial.

BACKGROUND AND OBJECTIVES: Single-incision transaxillary robotic thyroidectomy (START) requires substantial tissue disruption, which produces moderate-to-severe pain in the axilla and neck areas during the early postoperative period. This study aimed to investigate the analgesic effects of ultrasound-guided serratus-intercostal plane blocks and intermediate cervical plexus blocks (CPBs) on the early postoperative pain after START. METHODS: We randomized 22 patients to undergo either ultrasound-guided serratus-intercostal plane and intermediate CPBs (the block group, n = 11) or to not undergo any block (the control group, n = 11). We compared postoperative axillary pain, postoperative neck pain, and analgesic use between the groups during the first 24 hours. The rescue analgesics were intravenous fentanyl (0.5 µg/kg) in the postanesthesia care unit, and intravenous ketorolac tromethamine (30 mg) in the general ward. RESULTS: The block group showed consistently lower pain scores than the control group in the axillary area in the first 24 hours and in the neck area only in the first 3 hours after surgery. The numbers (proportions) of patients who required analgesics were 11 (100%) in the control group and 6 (54.5%) in the block group during the first 24 hours (P = 0.035). No adverse effect was observed related to the peripheral nerve blocks. CONCLUSIONS: After START, a serratus-intercostal plane block performed at the level of the third rib was an effective analgesic technique for axillary pain; however, the clinical effectiveness of intermediate CPB for neck pain may be limited.

Classic transcrural celiac plexus block simulated on 100 computed tomography images.

STUDY OBJECTIVE: To evaluate intra-abdominal needle trajectories of the classic transcrural celiac plexus block (tCPB) with a simulation technique. DESIGN: Classic tCPB technique cited from 10 latest authoritative textbooks were simulated on abdominal computed tomography images retrospectively. SETTING: University-affiliated community hospital. MEASUREMENTS: One hundred axial computed tomography images across the celiac trunk were retrieved. Three lines simulating classic tCPB were executed on each image. The organs traversed by each line were noted and analyzed. The frequencies of organ traverse were compared with the incidences described in the literature. MAIN RESULTS: All 3 lines traversed various organs with different frequencies. The right side line frequently traversed the right kidney (36%). The left side line always traversed the aorta (100%). The modified line on the right side frequently traversed the inferior vena cava (32%). The highest kidney traverse percentage on both sides and the highest aorta traverse percentage on the right side were observed in pancreatic cancer patients. CONCLUSIONS: Despite uncommon clinical complications, classic tCPB needle placement frequently traversed through several key organs in this simulation series. Organ penetrations could be avoided by needle trajectory adjustment.

Comparison of Combined (Deep and Superficial) and Intermediate Cervical Plexus Block by Use of Ultrasound Guidance for Carotid Endarterectomy.

OBJECTIVES: Carotid endarterectomy under regional anesthesia may be performed by using superficial, intermediate, deep or combined cervical plexus block. The authors compared the combined and intermediate cervical plexus block by use of ultrasound guidance in patients undergoing carotid endarterectomy. DESIGN: A prospective, randomized, double-blinded trial. SETTING: Education and research hospital. PARTICIPANTS: Adult patients undergoing carotid artery surgery. INTERVENTIONS: Forty-eight patients were randomized to receive either combined cervical plexus block (deep plus superficial) or intermediate cervical plexus block by use of ultrasound guidance for carotid endarterectomy. The primary outcome measure was the amount of supplemental 1% lidocaine used by the surgeon. Secondary outcome measures were the time for the first analgesic requirement after surgery, block-related complications, postoperative visual analog scale score, and patient and surgeon satisfaction. MEASUREMENTS AND MAIN RESULTS: Intraoperative supplemental lidocaine requirements were 3.0±1.9 mL in the combined-block group and 7.8±3.8 mL in the intermediate block group. These differences were statistically significant. There were no significant differences between the 2 groups in block-related complications and the time between the block completion and the first administration of the first dose of intravenous analgesic. In the combined-block group, maximum visual analog scale score was lower at 3 hours (2.2 [1-5] v 5.3 [3-8]), and patient satisfaction score was higher than the intermediate-block group (4.3 [3-5] v 3.1 [1-4]). One regional anesthesia procedure was converted to general anesthesia in the combined-block group. CONCLUSIONS: Ultrasound-guided combined cervical plexus block compared to intermediate cervical plexus block led to less additional analgesic use, lower visual analog scale score, and higher patient satisfaction.

Examination of regional anesthesia for carotid endarterectomy.

OBJECTIVE: Carotid endarterectomy is the most effective treatment for reducing the risk of stroke in patients with significant carotid stenosis. Few studies have focused on the failure rate of regional anesthesia. METHODS: Data of all patients undergoing carotid endarterectomy (June 2009 to December 2014) in a single center were collected. Combined deep and superficial cervical plexus block or superficial plexus block alone was used according to the attending anesthesiologist's choice and the patient's characteristics (eg, dual antiplatelet or anticoagulation therapy). Intraoperative remifentanil (0.025-0.05 µg/kg/min) was administered to maintain an adequate level of comfort, responsiveness, and cooperation. General anesthesia was planned only in the case of major contraindications or the patient's refusal of locoregional anesthesia. The primary end point of our study was the incidence of intraoperative conversion from locoregional to general anesthesia. RESULTS: A total of 2463 carotid endarterectomies were included in the analysis. Regional anesthesia was initially chosen in 2439 patients, whereas 24 patients received planned general anesthesia. In seven cases, regional anesthesia was converted to general anesthesia because of severe agitation of the patient (before clamping in four cases, after carotid clamping in two cases, and after declamping in one case). A shunt was used in 302 patients (12.3%) because of neurologic deterioration at the carotid clamping test. Intraoperative complications were emergent repeated surgical procedures in 13 cases (0.53%) because of acute neurologic deterioration, 1 intraoperative acute myocardial infarction (0.04%), and 3 cases (0.04%) of hemodynamically relevant supraventricular tachyarrhythmia. No intraoperative death occurred. In-hospital mortality was 0.12% (three patients). Major stroke occurred in 23 patients (0.93%); minor stroke occurred in 16 patients (0.65%). The combined stroke and death rate was 1.62% (40 patients). CONCLUSIONS: In our practice, carotid endarterectomy under regional anesthesia is safe and associated with a very low rate of conversion to general anesthesia.

Feasibility of ultrasound-guided capsule-sheath space block combined with anterior cervical cutaneous nerves block for thyroidectomy: an observational pilot study.

BACKGROUND: We evaluated the efficacy of a new anesthetic technique termed ultrasound-guided capsule-sheath space block (CSSB) combined with anterior cervical cutaneous nerve block (CCNB) for thyroidectomy. METHODS: The study included two parts: Part one was an imaging study to determine technique feasibility. The CSSB was performed on five healthy volunteers by introducing the needle 0.5 cm lateral to the probe under in-plane needle ultrasound guidance. After puncture of the false capsule and its subsequent contraction with the true capsule of thyroid, 10 mL of contrast medium was deposited slowly in the capsule-sheath space. The CCNB was performed bilaterally as follows: Under ultrasound guidance, a subcutaneous injection was made along the sternocleidomastoid using 10 mL of contrast medium which was followed by a girdle-shaped picchu raised from the cricoid cartilage to supraclavicular region. The spreading pattern of contrast medium was imaged using computed tomographic scanning. In part two (a clinical case series) the technique efficacy was evaluated. Seventy-eight patients undergoing thyroidectomy had ultrasound-guided CSSB and CCNB with local anesthetics. The sensory onset of CCNB, intraoperative hemodynamic parameters, and analgesic effect were assessed and complications were noted. RESULTS: The distribution of contrast medium was well defined. In part two the onset time of CCNB was 2.2 ± 0.7 min, and the hemodynamic parameters remained stable intraoperatively. The recall of visual analogue scale scores during surgery was 2 [1-4] for median (range). The patients' and surgeons' satisfaction scores were 2 [1-4] and 1 [1-3] for median (range). No serious complications occurred. CONCLUSIONS: Combining ultrasound-guided CSSB and CCNB is a feasible, effective and safe technique for thyroidectomy. TRIAL REGISTRATION: Current Controlled Trials ChiCTR-ONC-12002025. Registered 19 March 2012.

Incidence of and indications for conversion of cervical plexus block to general anesthesia in patients undergoing carotid surgery: a single center experience.

AIM: He aim of this paper was to investigate the incidence of and the indications for conversion to general anesthesia (GA) in a large single-center series of patients undergoing carotid surgery under cervical plexus block (CPB). METHODS: With IRB approval we retrospectively analyzed the medical records of all patients who underwent carotid surgery under CPB from November 2007 to October 2010. Cervical plexus was blocked at both the superficial and deep levels. An intraluminal shunt was inserted in patients who demonstrated signs of inadequate cerebral perfusion upon carotid clamping (CC). Propofol was given to patients reporting pain or discomfort throughout the procedure. The primary outcomes were the number and percentage of conversions to GA as well as the indications for this intervention. The secondary outcome was the incidence of partial cervical block failure, defined as the need for supplemental propofol administration for pain relief during surgery. RESULTS: In total, 1464 carotid surgical procedures were performed under CPB in 1305 consecutive patients during the investigated period. Conversion to GA was required in 17 (1.2%) patients. The most common reason for conversion to GA was persisting neurological deterioration upon CC and intraluminal shunt insertion, which was recorded in 8/17 (47.1%) procedures. Other indications to convert were systemic toxicity of local anesthetics, pain, general discomfort and restlessness during surgery, and acute myocardial infarction. CONCLUSION: Cervical plexus block for carotid surgery is associated with a low rate of conversions to GA. Neurological deterioration upon carotid clamping and local anesthetic toxicity are identified as the most common indications for such intervention.