Ultrasound-guided selective trunk block: Evaluation of ipsilateral sensorimotor block dynamics, hemidiaphragmatic function and efficacy for upper extremity surgery. A single-centre cohort study.

BACKGROUND: Selectively locating and blocking the individual trunks of the brachial plexus with small volumes of local anaesthetic, a selective trunk block (SeTB), may produce anaesthesia of the entire upper extremity except for the T2 dermatome. OBJECTIVE: This study aimed to evaluate the effects of an ultrasound-guided (USG) SeTB on ipsilateral sensorimotor block dynamics, hemidiaphragmatic function, and efficacy as an all-purpose regional anaesthetic technique for upper extremity surgery. DESIGN: Prospective cohort study. SETTING: Single-centre, university hospital in Hong Kong, China from February 2021 to July 2021. PATIENTS: Thirty patients (aged 53.2 ±â€Š14.8 years and BMI 23.8 ±â€Š3.6 kg m - 2 ), ASA physical status I to III, scheduled for upper extremity surgery under a brachial plexus block. INTERVENTIONS: USG SeTB with 25 ml (7, 8 and 10 ml to the superior, middle and inferior trunks, respectively) of a 1 : 1 mixture of 2% lidocaine with 1 : 200 000 epinephrine and 0.5% levobupivacaine. MAIN OUTCOME MEASURES: Ipsilateral sensorimotor blockade of the suprascapular (only motor), axillary, radial, ulnar, median and musculocutaneous nerves were assessed at regular intervals for 45 min. Ipsilateral hemidiaphragmatic excursion was also measured, at 30 min after the SeTB, using M-mode ultrasound. The SeTB was considered a success if it was possible to complete surgery without any rescue analgesia or conversion to general anaesthesia. RESULTS: Complete motor blockade of the suprascapular nerve was achieved in median [range] 5 [5 to 15] min. Complete sensory and motor blockade were achieved in all the other 5 nerves in 17.5 [10 to 30] and 15 [10 to 30] min respectively. The SeTB was successful in 93% and ipsilateral hemidiaphragmatic paresis (HDP) was present in 82%, of patients. CONCLUSION: SeTB produces sensorimotor blockade of the entire upper extremity, causes ipsilateral HDP, and is effective as the sole anaesthetic for surgery from the proximal humerus to the hand. TRIAL REGISTRION: ClinicalTrials.gov, Trial Registration No: NCT04752410, Date submitted for Registration: 09 February 2021, Date first posted: 12 February 2021, Dates of patient enrolment: 19 February 2021 to 27 July 2021 ( https://clinicaltrials.gov/ct2/show/NCT04752410 ).

Real-time ultrasound-guided versus anatomic landmark-based thoracic epidural placement: a prospective, randomized, superiority trial.

BACKGROUND: Thoracic epidural placement (TEP) using the conventional anatomic landmark-based technique is technically challenging, may require multiple attempts, and is associated with a high failure rate (12-40%). We hypothesized that real-time ultrasound guidance would be superior in the "first-pass" success rate of TEP, when compared with the conventional technique. METHODS: This prospective, randomized, superiority trial was conducted in a University hospital, and recruited 96 patients undergoing elective major abdominal or thoracic surgery and scheduled to receive a TEP for postoperative analgesia. Patients were randomly allocated to receive TEP using either the conventional technique (Gp-Conv, n = 48) or real-time ultrasound guidance (Gp-Usg, n = 48). The success of TEP was defined as eliciting loss of resistance technique and being able to insert the epidural catheter. The primary outcome variable was the "first-pass success rate" meaning the successful TEP at the first needle insertion without redirection or readvancement of the Tuohy needle. The secondary outcomes included the number of skin punctures, number of attempts, the overall success rate, TEP time, and total procedure time. RESULTS: The first-pass success rate of TEP was significantly higher (p = 0.002) in Gp-Usg (33/48 (68.8%); 95%CI 55.6 to 81.9) than in Gp-Conv (17/48 (35.4%); 95%CI 21.9 to 49.0). There was no statistically significant difference (p = 0.12) in the overall success rate of TEP between the 2 study groups (Gp-Usg; 48/48 (100%) vs. Gp-Conv; 44/48 (91.7%); 95%CI 83.9 to 99.5). Ultrasound guidance reduced the median number of skin punctures (Gp-Usg; 1 [1, 1] vs Gp-Conv; 2 [1, 2.2], p < 0.001) and attempts at TEP (Gp-Usg; 1 [1, 2] vs Gp-Conv; 3 [1, 7.2], p < 0.001) but the procedure took longer to perform (Gp-Usg; 15.5 [14, 20] min vs Gp-Conv; 10 [7, 14] min, p < 0.001). CONCLUSIONS: This study indicates that real-time ultrasound guidance is superior to a conventional anatomic landmark-based technique for first-pass success during TEP although it is achieved at the expense of a marginally longer total procedure time. Future research is warranted to evaluate the role of real-time ultrasound guidance for TEP in other groups of patients. TRIAL REGISTRATION: Thai Clinical Trials Registry; http://www.thaiclinicaltrials.org/ ; Trial ID: TCTR20200522002 , Registration date: 22/05/2020.

Risk predictive tools of perioperative drug hypersensitivity reaction: A case-control study.

OBJECTIVE: We aimed to determine the risk factors of perioperative drug hypersensitivity reaction (DHR) and develop a predictive score for use in clinical practice. METHODS: A case-control study was conducted in patients who underwent anesthesia at a tertiary hospital in Thailand, between 2015-2018. DHR cases were graded clinically from 1 to 4 according to the World Federation of Societies of Anesthesiologists by two anesthesiologists. Controls were randomly matched with cases (ratio 2:1) by age group and month and type of surgery. Patient and anesthesia-related factors and agents given intraoperatively were recorded. A risk score was derived from the coefficients of the significant predictors of the final multivariate logistic regression model. Risk scores, adjusted odds ratios (OR) for perioperative DHR and 95% confidence intervals (CI) were determined. RESULTS: Overall, 325 cases and 650 controls were recruited. The severity of DHR was grade 1 (72.9%), grade 2 (24%), and grade 3 (3.1%). Our risk predictive tools for perioperative DHR provided a sensitivity of 62% and specificity of 65%. Predictive scores of subgroups of moderate to severe DHR showed high specificity (80%) but low sensitivity (47%). Common predictors of overall DHR and moderate to severe DHR were history of drug allergy to 2 or more drug categories (score 2.5-3.5), being allergic to analgesics (score 2.5-4.0), and intraoperative morphine use (score of 1). The sole predictor of high-risk perioperative DHR (score ≥3.5) was airway management with an endotracheal tube intubation (OR 5.6, 95% CI 2.2-14.4) whereas history of allergic rhinitis (OR 11.7, 95% CI 1.3-105.1) was a predictor of high-risk moderate to severe DHR (score ≥2.5). CONCLUSIONS: Our predictive tool for perioperative DHR provided a modest predictive ability. History of drug allergies, rhinitis, morphine use and endotracheal intubation were significant risk factors of DHR after adjusting for age and type of surgery.

Ultrasound-guided subparaneural popliteal sciatic nerve block: there is more to it than meets the eyes.

The popliteal sciatic nerve block is routinely used for anesthesia and analgesia during foot and ankle surgery. This article reviews our current understanding of the anatomy of the sciatic nerve and discusses how fascial tissue layers associated with the nerve may affect block outcomes . The anatomy of the sciatic nerve is more complex than previously described. The tibial and common peroneal nerves within the sciatic nerve trunk appear to be centrally separated by the Compton-Cruveilhier septum and encompassed by their own paraneural sheaths. This unique internal architecture of the sciatic nerve appears to promote proximal spread of local anesthetic to the internal aspect of the sciatic nerve trunk after a subparaneural injection at or below the divergence of the tibial and common peroneal nerves.

Ultrasound-Guided Multilevel Thoracic Paravertebral Block and Its Efficacy for Surgical Anesthesia During Primary Breast Cancer Surgery.

PURPOSE: Thoracic paravertebral block (TPVB), in conjunction with intravenous sedation, is reported to provide surgical anesthesia for primary breast cancer surgery (PBCS). Although ultrasound-guided (USG) TPVB has been described, there are no reports of USG multilevel TPVB for surgical anesthesia during PBCS. The aim of this prospective observational study was to determine the feasibility of performing USG multilevel TPVB, at the T1-T6 vertebral levels (6m-TPVB), and to evaluate its efficacy in providing surgical anesthesia for PBCS. PATIENTS AND METHODS: Twenty-five female patients undergoing PBCS received an USG 6m-TPVB for surgical anesthesia. Four milliliters of ropivacaine 0.5% (with epinephrine 1:200,000) was injected at each vertebral level. Dexmedetomidine infusion (0.1-0.5 µg.kg-1.h-1) was used for conscious sedation. Success of the block, for surgical anesthesia, was defined as being able to complete the PBCS without having to resort to rescue analgesia or convert to GA. RESULTS: The USG 6m-TPVB was successfully performed on all 25 patients but it was effective as the sole anesthetic in only 20% (5/25) of patients. The remaining 80% (20/25) reported pain during separation of the breast from the pectoralis major muscle and its fascia. Surgery was successfully completed using small doses of intravenous ketamine (mean total dose, 38.0±20.5 mg) as supplementary analgesia. CONCLUSION: USG 6m-TPVB is technically feasible but does not consistently provide complete surgical anesthesia for PBCS that involves surgical dissection on the pectoralis major muscle and its fascia. Our data suggest that the pectoral nerves, which are not affected by a 6m-TPVB, are involved with afferent nociception.

High definition ultrasound imaging of the individual elements of the brachial plexus above the clavicle.

BACKGROUND AND OBJECTIVES: Ultrasonography of the brachial plexus (BP) has been described but there are limited data on visualization of the T1 ventral ramus and the inferior trunk. This prospective observational study aimed to evaluate a high definition ultrasound imaging technique to systematically identify the individual elements of the BP above the clavicle. METHODS: Five healthy young volunteers underwent high definition ultrasound imaging of the BP above the clavicle. The ultrasound scan sequence (transverse oblique scan) commenced at the supraclavicular fossa after which the transducer was slowly swept cranially to the upper part of the interscalene groove and then in the reverse direction to the supraclavicular fossa. The unique sonomorphology of the C7 transverse process was used as the key anatomic landmark to identify the individual elements of the BP in the recorded sonograms. RESULTS: The neural elements of the BP that were identified in all volunteers included the ventral rami of C5-T1, the three trunks, divisions of the superior trunk, and formation of the inferior trunk (C8-T1). The C6 ventral ramus exhibited echogenic internal septation with a split (bifid) appearance in four of the five volunteers. In three of the four volunteers with a bifid C6 ventral ramus, the C7 ventral ramus was also bifid. CONCLUSION: We have demonstrated that it is feasible to accurately identify majority of the main components of the BP above the clavicle, including the T1 ventral ramus and the formation of the inferior trunk, using high definition ultrasound imaging. TRIAL REGISTRATION NUMBER: ChiCTR1900021749.

Length of postanesthetic care unit stay in elderly patients after general anesthesia: a randomized controlled trial comparing desflurane and sevoflurane.

OBJECTIVE: The purpose of this study was to compare the length of postanesthetic care unit (PACU) stay and recovery profiles of elderly patients after general anesthesia between sevoflurane and desflurane. DESIGN: Randomized, double-blind, controlled clinical trial. SETTING: Tertiary care hospital, university hospital. PATIENTS: Eighty elderly patients undergoing nonemergency surgery under general anesthesia. INTERVENTION: Patients were randomly allocated into 2 groups: sevoflurane group (n = 38) and desflurane group (n = 42) in a double-blind manner. All of the patients underwent general anesthesia with oral endotracheal intubation using the same induction, muscle relaxants, and narcotics medication. When the operation was finished, the volatile agent was discontinued and muscle relaxation was reversed. MEASUREMENT: The length of PACU stay was recorded as the primary outcome. The recovery profiles (time to open eyes, time to follow to commands, and time to extubation) were assessed. MAIN RESULTS: There was no significance between the groups in age, sex, body mass index, American Society of Anesthesiologists physical status, type of surgery, duration of anesthesia, perioperative use of fentanyl, or blood loss. The length of PACU stay was not significantly different in the patients who recovered from sevoflurane (49.4 ± 23.1 minutes) or desflurane (50.1 ± 25.8 minutes) general anesthesia. Desflurane was significantly associated with faster early recovery than sevoflurane measured by time to open eyes (7.5 ± 3.4 vs 9.6 ± 4.6 minutes) and time to follow commands (9.0 ± 3.3 vs 11.2 ± 5.1 minutes), respectively. CONCLUSION: Desflurane was more associated with a faster early recovery (time to open the eyes and follow commands) than sevoflurane in elderly patients after general anesthesia. However, the length of PACU stay was similar in both groups.