Local and nerve block techniques for analgesia after shoulder surgery

Effect of intravenous magnesium on post-operative pain following Latarjet shoulder reconstruction

Background

Single injection ropivacaine interscalene anesthesia (ISA) is frequently used in Latarjet reconstruction to enhance post-operative analgesia. A potential limitation is the occurrence of severe rebound pain on block resolution. We investigated the effect of intravenous magnesium on post-operative pain, particularly at the transition of block resolution to multimodal analgesia.

Methods

Elective patients (n = 40) having Latarjet open shoulder reconstruction were randomised to receive either intravenous magnesium sulphate 50 mg/kg (M) or normal saline (S) before induction. Post-operatively, a standardised analgesic regimen was used, and post-operative pain was recorded using a verbal numerical rating assessment (VNRA) score. Requirement for injected opioid analgesia was recorded.

Results

ISA provided longstanding analgesia in all patients with block duration slightly prolonged in the magnesium group (16.7(1.0) (S), 17.8(1.3) h (M), p = 0.049). Magnesium resulted in less rebound pain following ISA resolution (VNRA 4.0 (0.6) M, 6.2 (0.8) S, p = 0.03) and lower pain intensity at 24 h. Four patients had nausea and two required rescue opioid injection.

Conclusion

Magnesium before Latarjet surgery results in less rebound pain following ropivacaine block and improves post-operative analgesia. Magnesium may be indicated in major upper limb surgery, where significant pain intensity is anticipated.

Level of evidence

Treatment study; Randomised blinded; Level 2.

Effect of cocktail therapy after arthroscopic rotator cuff repair: a randomized, double-blind trial

BACKGROUND

We investigated the effectiveness of cocktail therapy after arthroscopic rotator cuff repair (ARCR).

METHODS

We evaluated 128 shoulders undergoing ARCR and used block randomization to divide patients into 2 groups in this double-blind trial: The cocktail group received 20 mL of 0.75% ropivacaine, 5 mg of morphine, 0.3 mg of epinephrine, 2 mg of betamethasone, and saline solution to a total of 42 mL, whereas the control group received 20 mL of 0.75% ropivacaine and saline solution to a total of 42 mL. Postoperatively, one of the drug mixtures was injected into the glenohumeral joint, subacromial bursa, suprascapular nerve, and anterior, middle, and posterior parts of the deltoid muscle according to the treatment group. We recorded patients' visual analog scale scores preoperatively and at 4, 8, 16, 24, and 48 hours postoperatively; the number of patients using postoperative diclofenac suppositories and buprenorphine hydrochloride; the number of patients experiencing nausea; the number of patients with infection and delayed wound healing as adverse effects; the surgery time; the retear rate; and passive shoulder range of motion.

RESULTS

The cocktail group constituted 64 shoulders (50.0%), with 39 men (60.9%) and 25 women (39.1%); the mean age was 64.2 ± 10.2 years. The control group constituted 64 shoulders (50.0%), with 41 men (64.1%) and 23 women (35.9%); the mean age was 65.2 ± 7.5 years. We found no significant difference in age or sex between the 2 groups. There was also no significant difference in rotator cuff tear size or surgery time between the 2 groups. The visual analog scale scores at 8, 16, and 24 hours postoperatively were significantly lower in the cocktail group. The number of patients using suppositories was also significantly lower in the cocktail group. The number of patients receiving buprenorphine injections tended to be lower in the cocktail group, but the difference was not significant. Nausea occurred in 6.3% of patients in the cocktail group and 15.6% in the control group, but the difference was not significant. No infection or delayed wound healing occurred in either group. There was no significant difference in the retear rate between the 2 groups. Passive anterior elevation at 3 months postoperatively was significantly better in the cocktail group than in the control group.

CONCLUSION

We compared cocktail therapy and ropivacaine after ARCR and found no difference in results except for VAS score at 8, 16, and 24 hours postoperatively and frequency of postoperative suppository use without an apparent risk of infection or a detrimental effect on tendon healing.

Ultrasound-guided regional anesthesia for upper limb surgery

PURPOSE

The purpose of this module is to review the main ultrasound-guided approaches used for regional anesthesia of the upper limb.

PRINCIPAL FINDINGS

The anatomical configuration of the upper limb, with nerves often bundled around an artery, makes regional anesthesia of the arm both accessible and reliable. In-depth knowledge of upper limb anatomy is required to match the blocked territory with the surgical area. The interscalene block is the approach most commonly used for shoulder surgery. Supraclavicular, infraclavicular, and axillary blocks are indicated for elbow and forearm surgery. Puncture techniques have evolved dramatically with ultrasound guidance. Instead of targeting the nerves directly, it is now recommended to look for diffusion areas. Typically, local anesthetics are deposited around vessels, often as a single injection. Phrenic nerve block can occur with the interscalene and supraclavicular approaches. Ulnar nerve blockade is almost never achieved with the interscalene approach and not always present with a supraclavicular block. If ultrasound guidance is used, the risk for pneumothorax with a supraclavicular approach is reduced significantly. Nerve damage and vascular puncture are possible with all approaches. If an axillary approach is chosen, the consequences of vascular puncture can be minimized because this site is compressible.

CONCLUSIONS

Upper limb regional anesthesia has gained in popularity because of its effectiveness and the safety profile associated with ultrasound-guided techniques.