Determination of the Optimal Volume of 0.5% Ropivacaine in Single-Injection Retroclavicular Brachial Plexus Block for Arthroscopic Shoulder Surgery: A Phase I/II Trial.

BACKGROUND: A brachial plexus block plays an important role in providing perioperative analgesia for shoulder surgery; however, the inherent risk of phrenic nerve block and resulting hemidiaphragmatic paralysis may limit its use in patients with compromised pulmonary function. This study aimed to evaluate safety, efficacy, the maximum tolerated volume, and the optimal biological volume of 0.5% ropivacaine used in a single-injection retroclavicular brachial plexus block for arthroscopic shoulder surgery. METHODS: In this seamless single-arm exploratory phase I/II trial, a novel Bayesian optimal interval design was used to guide volume escalation for determination of the maximum tolerated volume, followed by sequential volume expansion using Bayesian optimal phase 2 design to establish the optimal biological volume. Fifty-four patients who underwent arthroscopic shoulder surgery received a single-injection retroclavicular brachial plexus block with 0.5% ropivacaine ranging from 15 mL to 40 mL. The primary outcomes were complete or partial hemidiaphragmatic paralysis in phase I, measured using ultrasound 30 min after block completion, and the block success in phase II, defined as achieving a total sensorimotor score ≥12 points and the total sensory score ≥3, measured through manual sensorimotor testing. RESULTS: The maximum tolerated volume for the single-injection retroclavicular brachial plexus block was determined to be 35 mL of 0.5% ropivacaine, with a hemidiaphragmatic paralysis rate of 0.09 (95% credible interval, 0 to 0.29). The optimal biological volume was found to be 25 mL, with a block success rate of 1.0 (95% credible interval, 0.95 to 1.0) and a negligible hemidiaphragmatic paralysis rate of 0.01 (95% credible interval, 0 to 0.06). CONCLUSIONS: A single-injection retroclavicular brachial plexus block using 25 mL of 0.5% ropivacaine produced consistent block success with a minimal HDP rate, suggesting the need for further studies to confirm this result in arthroscopic shoulder surgery.

Comparison between ultrasound-guided intertransverse process and erector spinae plane blocks for breast cancer surgery: A randomised controlled trial.

BACKGROUND: Clinical comparisons between intertransverse process block (ITPB) and erector spinae plane block (ESPB) are lacking. OBJECTIVE: This study aimed to compare their blocking profile and clinical efficacy in breast cancer surgery. DESIGN: Randomised, blinded, active-controlled superiority trial. SETTING: A tertiary hospital in China from 20 February to 31 July 2023. PATIENTS: Sixty-eight females undergoing unilateral breast cancer surgery. INTERVENTION: Patients were randomised to receive either ITPB performed at T2-6 (5 ml of 0.5% ropivacaine per level) or ESPB at T4 (25 ml of 0.5% ropivacaine). General anaesthesia and postoperative analgesia were standardised. MAIN OUTCOME MEASURES: The primary outcome was the number of blocked dermatomes at anterior T2-7, assessed 45 min after block completion, with a predefined superiority margin of 1.5 dermatomes. The important secondary outcome was the worst resting pain scores (11-point numerical rating scale) within 30 min in the recovery room, which was tested following a gatekeeping procedure. Other secondary outcomes included resting pain scores at various time points, use of rescue analgesics, opioid consumption, patient satisfaction, recovery quality score, and adverse effects within 24 h postoperatively. RESULTS: The ITPB group showed a median [q1, q3] of 5 [4, 6] blocked dermatomes at anterior T2-7, whereas the ESPB group had 1 [0, 4], with a median difference of 4 (95% confidence interval (CI), 3 to 4); the lower 95% CI limit exceeded the predefined superiority margin of 1.5 (superiority P < 0.001). Worst resting pain scores within 30 min in the recovery room in the ITPB group were 1 [0, 2] vs. 3 [1, 4] in the ESPB group, with a median difference of -1 (95% CI, -2 to 0; P = 0.004). Patients in the ITPB group required fewer rescue analgesics within 30 min in the recovery room than did those in the ESPB group. No other clinically relevant results were observed in the secondary outcomes. CONCLUSIONS: Although ITPB demonstrated more consistent anterior dermatomal spread and improved immediate postoperative analgesia compared to ESPB, no additional benefits were identified for breast cancer surgery. Future studies may investigate the potential of ITPB for surgical anaesthesia. TRIAL REGISTRATION: www.chictr.org.cn (ChiCTR2300068454).

Comparison Between Subparaneural Upper Trunk and Conventional Interscalene Blocks for Arthroscopic Shoulder Surgery: A Randomized Noninferiority Trial.

BACKGROUND: Although interscalene nerve block is the standard for shoulder analgesia, the risk of hemidiaphragmatic paralysis restricts its use in patients with compromised pulmonary function. We hypothesized that a novel subparaneural upper trunk block would provide noninferior postoperative analgesia but superior diaphragmatic sparing effect compared to interscalene block. METHODS: This randomized controlled trial comprised 96 patients who underwent arthroscopic shoulder surgery under either subparaneural upper trunk block (5 mL of 0.5% ropivacaine) or interscalene block (15 mL of 0.5% ropivacaine), followed by supraclavicular nerve block (5 mL of 0.5% ropivacaine). General anesthesia was standardized. The coprimary outcomes were (1) recovery room resting pain score at 30 minutes, measured on an 11-point numerical rating scale, with a prespecified noninferiority margin of 1 point and (2) the incidence of hemidiaphragmatic paralysis, diagnosed using ultrasound. Among secondary outcomes, resting pain scores were assessed with numerical rating scale at 4, 8, and 24 hours postoperatively. RESULTS: Recovery room resting pain scores at 30 minutes were 0 (0-1) in the subparaneural upper trunk group versus 0 (0-0) in the interscalene group, with a median difference of 0 (95% CI, 0-0); the upper 95% CI limit was lower than the prespecified noninferiority margin (noninferiority P < .001). Hemidiaphragmatic paralysis was observed in 16.7% of patients in the subparaneural upper trunk group versus 100% of those in the interscalene group (RR, 0.17; 95% CI, 0.09-0.31; P < .001), with complete paralysis occurring in 6.3% and 93.7% of patients, respectively. In this study, any reported differences in pain scores at 4, 8, and 24 hours postoperatively were not clinically important. CONCLUSIONS: The subparaneural upper trunk block compared to interscalene block provided noninferior analgesia at 30 minutes in the recovery room after arthroscopic shoulder surgery but resulted in less hemidiaphragmatic paralysis.

Comparison between ultrasound-guided multi-injection intertransverse process and thoracic paravertebral blocks for major breast cancer surgery: a randomized non-inferiority trial.

BACKGROUND: This study investigated whether a novel multi-injection intertransverse process block could provide non-inferior analgesia and recovery quality following major breast cancer surgery compared with the multi-injection thoracic paravertebral block. METHODS: Eighty-eight females who underwent mastectomy plus sentinel or axillary lymph node dissection were randomized to receive either intertransverse process block or thoracic paravertebral block, both performed at T2-6 with 5 mL of 0.5% ropivacaine per level. The primary outcome was the worst resting pain score (11-point Numerical Rating Scale) within 30 min in the recovery room. The secondary outcome was recovery quality (15-item quality of recovery scale) 24 hours after surgery, which was tested following a gatekeeping procedure. RESULTS: The worst resting pain scores were 0 (0, 1) in the intertransverse process block group vs 0.5 (0, 2) in the thoracic paravertebral block group, with a median difference of 0 (95% CI 0 to 0); the upper 95% CI limit was lower than the prespecified non-inferiority margin of 1 point (non-inferiority p<0.001). Aggregate scores of recovery quality at 24 hours postoperatively were 137.5 (126.5, 142.8) and 137.5 (127.8, 145.0) for the intertransverse process and thoracic paravertebral block groups, respectively, with a median difference of -1 (95% CI -6 to 3); the lower 95% CI limit was larger than the prespecified non-inferiority margin of -8 (non-inferiority p=0.006). CONCLUSIONS: Compared with a multi-injection thoracic paravertebral block, the multi-injection intertransverse process block provided non-inferior analgesia within 30 min in the recovery room and recovery quality at 24 hours following major breast cancer surgery in females. TRIAL REGISTRATION NUMBER: ChiCTR2000037963.

Five-year comparative study of thin-strut rapamycin-eluting bioabsorbable scaffold with metallic drug-eluting stent in porcine coronary artery.

Objectives: Using quantitative coronary angiography (QCA), optical coherence tomography (OCT), histomorphometry, and pharmacokinetics, this study tried to evaluate the safety and efficacy of Biomagic rapamycin-eluting bioabsorbable scaffold (BVS) in non-atherosclerotic porcine coronary arteries. Background: Biomagic BVS is a new generation of thin-strut bioabsorbable scaffold. We conducted comparative study detailing pathological response, safety and efficacy of Biomagic BVS and the Firebird2 rapamycin-eluting cobalt-based alloy stent (DES) in a porcine coronary artery model. The animals were followed up at 14 days, 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after stent implantation. Methods: A total of 143 devices (95 Biomagic and 48 Firebird2) were implanted in 2 or 3 main coronary arteries of 76 nonatherosclerotic swine and examined by QCA, OCT, light microscopy, and pharmacokinetics analyses at various time points. Results: Vascular responses to Biomagic and Firebird2 were largely comparable at all time points, with struts being sequestered within the neointima. The degree of inflammation of both devices was mild to moderate, although the Biomagic score was higher at 14 days to 24 months. However, there was no statistical difference between the two groups except 14 days. At each follow-up time point, the percentage of area stenosis in the Biomagic group was greater than that in the Firebird 2 group, but there was no statistical difference between the two groups at 3 and 12 months. The extent of fibrin deposition was similar between Biomagic and Firebird2, which peaked at 1 month and decreased rapidly thereafter. Pharmacokinetic study showed that coronary tissue sirolimus concentration remained above 2 ng/mg of tissue at 28 day. Histomorphometry showed expansile remodeling of Biomagic-implanted arteries starting after 12 months, and lumen area was significantly greater in Biomagic than Firebird2 at 36 and 42 months. These changes correlated with dismantling of Biomagic seen after 12 months. OCT images confirmed that degradation of Biomagic was complete by 36 months. Conclusions: Biomagic demonstrates comparable long-term safety to Firebird2 in porcine coronary arteries with mild to moderate inflammation. Although Biomagic was associated with greater percent stenosis relative to Firebird2 within 36 months, expansile remodeling was observed after 12 months in Biomagic with significantly greater lumen area at ≥36 months. Scaffold resorption is considered complete at 36 months.