A combination of infraclavicular and suprascapular nerve blocks for total shoulder arthroplasty: A case series.

BACKGROUND: Shoulder arthroplasty is associated with significant post-operative pain. Interscalene plexus block is the gold standard for pain management in patients undergoing this surgery, however, alternatives are currently being developed. We hypothesized that a combination of anterior suprascapular nerve block and lateral sagittal infraclavicular block would provide effective post-operative analgesia. Primary aims for this study were to document numeric rating scale (NRS) pain score and use of oral morphine equivalents (OMEq) during the first 24 hours after surgery. Secondary aim was to determine the incidence of hemidiaphragmatic paralysis. METHODS: Twenty patients (ASA physical status I-III) scheduled for shoulder arthroplasty were studied. Four mL ropivacaine 0.5% was administered for the suprascapular nerve block and 15 mL ropivacaine 0.75% for the infraclavicular block. Surgery was performed under general anaesthesia. Paracetamol and prolonged-release oxycodone were prescribed as post-operative analgesics. Morphine and oxycodone were prescribed as rescue pain medication. Diaphragm status was assessed by ultrasound. RESULTS: Median NRS (0-10) at 1, 3, 6, 8 and 24 hours post-operatively were 1, 0, 0, 0 and 3, respectively. NRS at rest during the first 24 post-operative hours was 4 (2.5-4.5 [0-5]), median (IQR [range]). Maximum NRS was 6.5 (5-8 [0-10]) median (IQR [range]). Total OMEq during the first 24 post-operative hours was 52.5 mg (30-60 [26.4-121.5]) median (IQR [range]). Hemidiaphragmatic paralysis was diagnosed in one patient (5%). CONCLUSIONS: The combination of suprascapular and infraclavicular nerve block shows an encouraging post-operative analgesic profile and a low risk for hemidiaphragmatic paralysis after total shoulder arthroplasty.

Brachial plexus block of the posterior and the lateral cord using ropivacaine 7.5 mg/mL.

BACKGROUND: We recently showed that the novel combination of a superficial cervical plexus block, a suprascapular nerve block, and the lateral sagittal infraclavicular brachial plexus block (LSIB) provides an alternative anaesthetic method for arthroscopic shoulder surgery. In this study, we hypothesised that the LSIB dose for this shoulder block could be significantly reduced by injecting only towards the shoulder relevant posterior and lateral cords. Our aim was to determine the minimum effective volume in 50% of the patients (MEV50 ) and to estimate the MEV95, when using ropivacaine 7.5 mg/mL to block these cords. METHODS: Twenty-three adult patients scheduled for hand surgery participated in the study. Considering the artery as a clock face with 12 o'clock ventral, the designated volume was injected immediately outside the arterial wall and between 8 and 9 o´clock. The in-plane technique was used. Block success was assessed 30 minutes after withdrawal of the needle. Successful posterior cord block was defined as anaesthesia or analgesia of the axillary nerve. Successful lateral cord block was defined as either anaesthesia or analgesia, or >50% motor block of the musculocutaneous nerve. MEV50 was determined by the staircase up-and-down method. Logistic regression and probit transformation were applied to estimate MEV95 . RESULTS: MEV50 and MEV95 were 7.8 mL [95% confidence interval (CI), 7.3-8.4] and 9.0 mL (95% CI, 7.8-10.3), respectively. CONCLUSION: For single-deposit infraclavicular posterior and lateral cord block, the MEV95 of ropivacaine 7.5 mg/mL was estimated to 9.0 mL.