Prozessmanagement bei axillären Plexusblockaden

Sucrose Acetate Isobutyrate as an In situ Forming Implant for Sustained Release of Local Anesthetics

OBJECTIVE

In this study, an injectable Sucrose Acetate Isobutyrate (SAIB) drug delivery system (SADS) was designed and fabricated for the sustained release of Ropivacaine (RP) to prolong the duration of local anesthesia.

METHODS

By mixing SAIB, RP, and N-methyl-2-pyrrolidone, the SADS was prepared in a sol state with low viscosity before injection. After subcutaneous injection, the pre-gel solution underwent gelation in situ to form a drug-released depot.

RESULT

The in vitro release profiles and in vivo pharmacokinetic analysis indicated that RP-SADS had suitable controlled release properties. Particularly, the RP-SADS significantly reduced the initial burst release after subcutaneous injection in rats.

CONCLUSION

In a pharmacodynamic analysis of rats, the duration of nerve blockade was prolonged by over 3-fold for the RP-SADS formulation compared to RP solution. Additionally, RP-SADS showed good biocompatibility in vitro and in vivo. Thus, the SADS-based depot technology is a safe drug delivery strategy for the sustained release of local anesthetics with long-term analgesia effects.

[Ultrasound guidance improves the success rate of axillary plexus block: a meta-analysis]

OBJECTIVE

To evaluate the value of real-time ultrasound (US) guidance for axillary brachial plexus block (AXB) through the success rate and the onset time.

METHODS

The meta-analysis was carried out in the Anesthesiology Department of the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China. A literature search of Medline, Embase, Cochrane database from the years 2004 to 2014 was performed. The literature searches were carried out using medical subject headings and free-text word: "axilla", "axillary", "brachial plexus", "ultrasonography", "ultrasound", "ultrasonics". Two different reviewers carried out the search and evaluated studies independently.

RESULTS

Seven randomized controlled trials, one cohort study and three retrospective studies were included. A total of 2042 patients were identified. 1157 patients underwent AXB using US guidance (US group) and the controlled group included 885 patients (246 patients using traditional approach (TRAD) and 639 patients using nerve stimulation (NS)). Our analysis showed that the success rate was higher in the US group compared to the controlled group (90.64% vs. 82.21%, p<0.00001). The average time to perform the block and the onset of sensory time were shorter in the US group than the controlled group.

CONCLUSION

The present study demonstrated that the real-time ultrasound guidance for axillary brachial plexus block improves the success rate and reduce the mean time to onset of anesthesia and the time of block performance.

Ultrasound guidance improves the success rate of axillary plexus block: a meta-analysis

OBJECTIVE

To evaluate the value of real-time ultrasound (US) guidance for axillary brachial plexus block (AXB) through the success rate and the onset time.

METHODS

The meta-analysis was carried out in the Anesthesiology Department of the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China. A literature search of Medline, EMBASE, Cochrane database from the years 2004 to 2014 was performed. The literature searches were carried out using medical subject headings and free-text word: "axilla", "axillary", "brachial plexus", "ultrasonography", "ultrasound", "ultrasonics". Two different reviewers carried out the search and evaluated studies independently.

RESULTS

Seven randomized controlled trials, one cohort study and three retrospective studies were included. A total of 2042 patients were identified. 1157 patients underwent AXB using US guidance (US group) and the controlled group included 885 patients (246 patients using traditional approach (TRAD) and 639 patients using nerve stimulation (NS)). Our analysis showed that the success rate was higher in the US group compared to the controlled group (90.64% vs. 82.21%, p<0.00001). The average time to perform the block and the onset of sensory time were shorter in the US group than the controlled group.

CONCLUSION

The present study demonstrated that the real-time ultrasound guidance for axillary brachial plexus block improves the success rate and reduce the mean time to onset of anesthesia and the time of block performance.

Cost-effectiveness of ultrasound vs nerve stimulation guidance for continuous sciatic nerve block

BACKGROUND

This study assessed the cost-effectiveness of ultrasound (US) vs nerve stimulation (NS) guidance for continuous sciatic nerve block in Danish elective patients undergoing major foot and ankle surgery.

METHODS

> A cost-effectiveness analysis was conducted alongside a randomized controlled trial. A total of 100 consecutive patients were randomly assigned to either traditional electrical NS or US technique for catheter insertion guidance. Information on effects and costs were collected prospectively. An incremental cost-effectiveness ratio (ICER) was calculated as the extra cost per extra successful nerve block. The robustness of the ICER was investigated using 4000 non-parametric bias-corrected bootstrap replicates to calculate the likelihood that US leads to better effect and lower costs compared with NS guidance.

RESULTS

The mean ICER was negative, indicating that US was a dominating technology providing both higher quality and lower costs. The likelihood of US being more effective and cheaper than NS was estimated to 84.7%.

CONCLUSIONS

In this trial, US was cost-effective. Assuming that the results are fairly generalizable, US should be the preferred catheter insertion technique in larger anaesthesia departments.

[Ultrasound-guided axillary brachial plexus block: learning curve and results]

BACKGROUND AND OBJECTIVE

The use of ultrasound in regional anesthesia requires the acquisition of new knowledge and skills not only by anesthesiologists in training but also by anesthesiologists experienced in neurostimulation-guided peripheral nerve blocks. We studied the effect of training on 2 anesthesiologists who were skilled in neurostimulation-guided regional anesthesia.

PATIENTS AND METHODS

Observational, controlled study of the first 45 ultrasound-guided axillary blocks of the brachial plexus performed by two anesthesiologists with expertise in the neurostimulation-guided axillary procedure. For analysis of results, groups of 15 patients from each anesthesiologist were assigned consecutively (G15, G30 and G45). We assessed the duration of the block procedure, the incidence of vascular puncture and effectiveness of the block.

RESULTS

The mean (SD) duration of the procedure was 547 (16) seconds in G15. It was significantly lower in G30 and G45 (893 [104] seconds and 397 [111] seconds). The incidence of vascular puncture dropped significantly after completion of the first 15 blocks, from 20% in 615 to 3% in G30 and 0% in G45. The results of the block procedure also significantly improved after the first 15 blocks: 89% effectiveness in 615, 93% in G30, and 100% in G45. The variables assessed were similar for the 2 anesthesiologists.

CONCLUSIONS

For an anesthesiologist with experience establishing a conventional axillary brachial plexus block using a nerve stimulator, 15 ultrasound-guided axillary blocks are required before good results can be expected with the new procedure.

Comparision of nerve stimulator and ultrasonography as the techniques applied for brachial plexus anesthesia

Background

Brachial plexus block is useful for upper extremity surgery, and many techniques are available. The aim of our study was to compare the efficacy of axillary brachial plexus block using an ultrasound technique to the peripheral nerve stimulation technique.

Methods

60 patients scheduled for surgery of the forearm or hand were randomly allocated into two groups (n = 30 per group). For Group 1; US, and for Group 2 PNS was applied. The quality and the onset of the sensorial and motor blockade were assessed. The sensorial blockade, motor blockade time and quality of blockade were compared among the cases.

Results

The time needed to perform the axillary brachial plexus block averaged is similar in both groups (p > 0.05). Although not significant statistically, it was observed that the sensory block had formed earlier in Group 1 (p > 0.05). But the degree of motor blockade was intenser in Group 1 than in Group 2 (p < 0.05).

Conclusions

Ultrasound offers a new possibility for identifiying the nerves of the brachial plexus for regional anesthesia. The ultrasound-guided axillary brachial plexus block is a safe method with faster onset time and better quality of motor blockade compared to peripheral nerve stimulation technique.

[Contribution of ultrasound guidance to the performance of the axillary brachial plexus block with multiple nerve stimulation]

OBJECTIVE

To evaluate whether ultrasound imaging of vascular nerve structures improves anesthetic block quality and decreases the incidence of vascular puncture in the performance of an axillary brachial plexus block with multiple nerve stimulation.

PATIENTS AND METHODS

Randomized trial enrolling 129 patients assigned to 2 groups. In group 1, axillary brachial plexus nerves were located by nerve stimulation with ultrasound guidance. In group 2, only conventional multiple nerve stimulation was used. We analyzed the number of nerves located, time required to perform the block, anesthetic quality, and the number of accidental vascular punctures.

RESULTS

Four nerves were located in 43% of the patients in group 1 and 38% of those in group 2. More time was taken in performing the block in group 1 than in group 2 (mean [SD] of 350 [40] seconds vs. 291 [58] seconds, respectively; P < .05). The incidence of vascular puncture was significantly lower in group 1 (8%) than in group 2 (28%) (odds ratio, 4 [95% confidence interval, 2-13]; P < .01). Ten and 20 minutes after puncture, the quality of sensory and motor blockade was significantly better in group 1. Block success was similar in the 2 groups (98.5% and 94% respectively).

CONCLUSIONS

Combining ultrasound guidance with nerve stimulation improves the anesthetic quality of an axillary brachial plexus block, decreases the likelihood of vascular puncture, and slightly increases the amount of time required to perform the procedure.

[The value of regional and general anaesthesia in orthopaedic surgery]

Adequate postoperative pain management is of major importance for a short rehabilitation time after painful orthopaedic surgery. Multimodal pathways have been established to achieve a surgical patient free of pain and complications. Peripheral and central nerve blocks are a fundamental part of these interdisciplinary strategies and are already implemented in orthopaedic surgical care. This article summarises the value of special anaesthetic techniques, especially regional anaesthesia, in orthopaedic surgery and discusses their impact on several postoperative outcome goals.