ABSTRACT
PURPOSE: This systematic review and meta-analysis aims to assess the efficacy and safety of dexmedetomidine as an adjuvant to intra-articular (IA) injections of local anesthetics (LA) in adult patients undergoing knee arthroscopy. METHODS: We searched MEDLINE, Embase, and Cochrane Library for randomized controlled trials (RCTs) comparing IA dexmedetomidine plus LA versus LA alone for knee arthroscopy in adults. We used the DerSimonian and Laird random-effects model for all outcomes, and conducted a sensitivity analysis with the leave-one-out method, as well as a subgroup analysis for the type of LA. We used R version 4.1.2 for all statistical analyses. RESULTS: We included 16 RCT encompassing 799 patients, of whom 49.8% received IA dexmedetomidine. In the pooled analysis, time to first analgesia rescue was prolonged in almost 4 hours with the use of dexmedetomidine (MD 229 min; p<0.001). We found statistically significant differences favoring dexmedetomidine in pain scores at rest and movement throughout the first 2, 6, 12 and 24 hours postoperatively (p<0.001). Although the mean difference (MD) ranged from -0.3 to -0.9 cm, corresponding to a 3 to 9% reduction in pain scores, this change is not clinically significant when compared to the minimal clinically important difference (MCID). Additionally, the intervention group showed a statistically significant reduction in cumulative opioid consumption over 24 hours (MD -4.5 mg; p<0.001). However, this reduction did not meet the threshold for the MCID. There was no difference between groups on the incidence of hypotension (p=0.190), bradycardia (p=0.430) and postoperative nausea and vomiting (p=0.550). CONCLUSIONS: Adding dexmedetomidine to LA in IA injections for knee arthroscopy significantly extended analgesia duration. Additionally, it lowered pain scores and opioid use, although these effects did not reach the MCID. Furthermore, this addition did not increase the risk of adverse events.
ABSTRACT
Liposomal bupivacaine is a long-acting local anesthetic drug that provides extended analgesia. A 45-year-old man with metastatic colon cancer and an intrathecal morphine pump for chronic pain underwent a transverse colectomy for a malignant transverse colon obstruction in this case report. The patient reported severe pain despite preoperative fascial plane blocks with liposomal bupivacaine and postoperative pain management strategies. As a result, an exploratory laparotomy was performed to rule out any underlying causes, but no new injuries were discovered. On postoperative day 1, a thoracic epidural catheter was inserted to provide better pain relief for the patient. The patient's pain was well-controlled by postoperative day 4, allowing the epidural catheter to be removed. On postoperative day 5, the patient was discharged home without complications. This case highlights the difficulties in managing post-laparotomy pain as well as the potential benefits of combining multiple analgesic modalities. It also emphasizes the pharmacokinetic properties of liposomal bupivacaine, emphasizing the need for caution due to its prolonged systemic presence and potential for systemic anesthetic toxicity.
ABSTRACT
The interscalene block (ISB) is the standard regional anesthesia for shoulder arthroscopy. However, the superior trunk block (STB) is an alternative with a potentially safer profile. This meta-analysis aimed to compare the incidence and degree of hemidiaphragmatic paralysis and block efficacy of these techniques. We searched MEDLINE, EMBASE, Scopus, and Cochrane databases to identify randomized controlled trials (RCTs). The main outcome was total hemidiaphragmatic paralysis. We used the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework to assess the certainty of evidence. Four RCTs and 359 patients were included. The STB group showed lower total hemidiaphragmatic paralysis (RR 0.07; 95% CI 0.04 to 0.14; p<0.0001). The incidence of subjective dyspnea (p = 0.002) and Horner's syndrome (p<0.001) was significantly lower with STB relative to ISB. There was no significant difference between groups in block duration (p = 0.67). There was a high certainty of evidence in the main outcome as per the GRADE framework. Our findings suggest that STB has a better safety profile than ISB, resulting in lower rates of hemidiaphragmatic paralysis and dyspnea while providing a similar block. Therefore, STB could be preferred to ISB, especially in patients susceptible to phrenic nerve paralysis complications.
