Anesthesiology
-
Electroencephalogram burst suppression can be associated with postoperative delirium; however, the results of relevant studies are discrepant. This systematic review and meta-analysis aimed to assess the association between intraoperative burst suppression and postoperative delirium in adult surgical patients. ⋯ The meta-analysis suggests an association between intraoperative burst suppression and postoperative delirium; however, the quality of evidence was very low. The limited number of studies and substantial heterogeneity across them emphasize the need for further high-quality studies to establish a more robust conclusion.
-
Numerous, sometimes conflicting, changes in brain functional connectivity have been associated with the transition from wakefulness to unresponsiveness at induction of general anesthesia. However, relatively few studies have looked at the detailed time evolution of the transition, for different electroencephalogram (EEG) frequency bands, and in the clinical scenario of surgical patients undergoing general anesthesia. ⋯ Propofol-induced loss of consciousness in surgical patients is associated with a global breakdown in low-frequency directed functional connectivity, coupled with a high-frequency increase between closely located brain regions. At loss of consciousness, Granger causality shows more pronounced changes than coherence.
-
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 the safety, efficacy, maximum tolerated volume, and optimal biologic volume of 0.5% ropivacaine used in a single-injection retroclavicular brachial plexus block for arthroscopic shoulder surgery. ⋯ A single-injection retroclavicular brachial plexus block using 25 ml of 0.5% ropivacaine produced consistent block success with a minimal hemidiaphragmatic paralysis rate, suggesting the need for further studies to confirm this result in arthroscopic shoulder surgery.