A practical guide to commonly performed ultrasound-guided peripheral-nerve blocks

Application of Femoral Nerve Block in Treating Great Saphenous Vein Insufficiency by Endovenous Radiofrequency Ablation Combined with Punctate Stripping

PURPOSE

To evaluate the efficacy and safety of ultrasound-guided femoral nerve block (FNB) in treating great saphenous vein (GSV) insufficiency by endovenous radiofrequency ablation (EVRA) combined with punctate stripping (PS).

METHODS

This was a single-center, retrospective cohort study. A total of 135 patients were divided into Group A (59 patients) and Group B (76 patients). All patients received tumescent anesthesia during the operation, and group A received an additional ultrasound-guided FNB before the procedure. Intraoperative and postoperative pain score, the volume of tumescent anesthesia solution (TAS), and other indicators were compared in two groups.

RESULTS

Group A had a significantly lower intraoperative pain visual analog scale than group B (2.7 ± 1.2 vs 5.2 ± 1.5, P < 0.001). The volume of TAS in group A was significantly lower than that in group B (198 ± 26.6 ml vs 338 ± 34.7 ml, P < 0.001). Postoperative muscle strength of group A was significantly decreased compared with group B (54.2% vs 3.90%, P < 0.001); no patient had severe limitation of active movements in both groups, and all motor blocks recovered within 24 h. The incidence of skin ecchymosis in group A was lower than that in group B (18.6% vs 46.1%, P = 0.001). The operation duration of the two groups had no statistically significant difference.

CONCLUSIONS

Ultrasound-guided FNB in treating GSV insufficiency by EVRA combined with PS significantly relieved intraoperative pain and reduced the dosage of TAS and the incidence of skin ecchymosis without increasing the complications of anesthesia or any other surgical complications.

A simple guide to regional anaesthesia

Regional anaesthesia is widely used in modern anaesthetic practice for perioperative and postoperative analgesia. In the operating theatre, regional anaesthesia is used both on its own and in combination with other techniques (general anaesthesia and sedation). Regional anaesthesia is now a core skill set in anaesthetic training. This article provides a basic outline of regional anaesthesia for surgeons and other non-anaesthetic staff working with anaesthetists, reviewing preparation, consent, basic and specialist equipment, central neuraxial blocks (spinal, epidural and caudal), trunk blocks, upper limb blocks (interscalene, supraclavicular, infraclavicular and axillary) and lower limb blocks (femoral, fascia iliaca, sciatic, popliteal and ankle). It also discusses the pharmacology of the agents used and common complications.

Ultrasound-Guided Subgluteal Sciatic Nerve Perineural Injection: Report on Safety and Efficacy at a Single Institution

OBJECTIVES

To determine the safety and efficacy of ultrasound (US)-guided subgluteal sciatic nerve injections.

METHODS

A retrospective chart review of US-guided subgluteal sciatic nerve injections at our institution was performed.

RESULTS

Of 221 US-guided subgluteal sciatic nerve injections, 100% achieved technical success, with no postprocedure complications. Sixty-eight percent of patients with follow-up reported symptom relief. Most patients with no relief had suboptimal preprocedure screening.

CONCLUSIONS

With appropriate screening, our technique of US-guided subgluteal sciatic nerve injection is safe and effective.

Integration of free-hand 3D ultrasound and mobile C-arm cone-beam CT: Feasibility and characterization for real-time guidance of needle insertion

This work presents development of an integrated ultrasound (US)-cone-beam CT (CBCT) system for image-guided needle interventions, combining a low-cost ultrasound system (Interson VC 7.5MHz, Pleasanton, CA) with a mobile C-arm for fluoroscopy and CBCT via use of a surgical tracker. Imaging performance of the ultrasound system was characterized in terms of depth-dependent contrast-to-noise ratio (CNR) and spatial resolution. US-CBCT system was evaluated in phantom studies simulating three needle-based procedures: drug delivery, tumor ablation, and lumbar puncture. Low-cost ultrasound provided flexibility but exhibited modest CNR and spatial resolution that is likely limited to fairly superficial applications within a ∼10cm depth of view. Needle tip localization demonstrated target registration error 2.1-3.0mm using fiducial-based registration.

The Efficacy of Femoral Block and Unilateral Spinal Anaesthesia on Analgesia, Haemodynamics and Mobilization in Patients undergoing Endovenous Ablation in the Lower Extremity

OBJECTIVE

This study aimed to investigate the efficacy of femoral block and unilateral spinal anaesthesia on analgesia, haemodynamics and mobilization during endovenous ablation in patients with lower extremity venous insufficiency.

METHODS

Forty patients of ASA physical status I and II, with ages ranging between 30 and 45 years, and who were scheduled for endovenous laser ablation for varicose veins were prospectively enrolled in this study. Patients were randomized into a unilateral spinal anaesthesia group (group HS, n=20) or a femoral block group (group F, n=20). Group HS received 7.5-10 mg of heavy bupivacaine for unilateral spinal anaesthesia, while group F received 100 mg prilocaine for femoral block with ultrasound guidance. The level of motor blockage (Bromage score), visual pain score, mean heart rate and mean arterial pressures were recorded at postoperative 0, 1, 2, 3d and 6 h, respectively.

RESULTS

Perioperative visual pain score values in both groups were <4. None of the groups required an additional analgesic agent. Bromage scores were significantly lower in group F than in group HS during the postoperative period (p<0.01). Motor function returned to normal in all patients at 3 h in group F and at 6 h in group HS. Postoperative mean heart rate and arterial pressure did not differ between the groups (p>0.05).

CONCLUSION

In patients with lower extremity venous insufficiency who were undergoing endovenous laser ablation, an ultrasound-guided femoral block provided similar analgesia with that of unilateral spinal anaesthesia. In group F, the duration of anaesthesia and mobilization time was shorter.

Ultrasound-Guided Peripheral Nerve Injection Techniques

OBJECTIVE

Peripheral nerves are well seen using ultrasound (US) imaging, making US an ideal modality for image-guided nerve injections. This article provides a technical guide for common upper and lower extremity peripheral nerve injections, including the median, ulnar, and radial nerves in the upper extremity and the lateral femoral cutaneous, sciatic, common peroneal, tibial, and sural nerves in the lower extremity.

CONCLUSION

US is an effective modality for use in common upper and lower extremity peripheral nerve injections. With correct technique, peripheral nerve injections can be performed safely and are useful for both diagnostic evaluation of and therapy for peripheral neuropathy.

A novel suture method to place and adjust peripheral nerve catheters

We have developed a peripheral nerve catheter, attached to a needle, which works like an adjustable suture. We used in‐plane ultrasound guidance to place 45 catheters close to the femoral, saphenous, sciatic and distal tibial nerves in cadaver legs. We displaced catheters after their initial placement and then attempted to return them to their original positions. We used ultrasound to evaluate the initial and secondary catheter placements and the spread of injectate around the nerves. In 10 cases, we confirmed catheter position by magnetic resonance imaging. We judged 43/45 initial placements successful and 42/43 secondary placements successful by ultrasound, confirmed in 10/10 cases by magnetic resonance imaging.

Brachial plexus anesthesia: A review of the relevant anatomy, complications, and anatomical variations

The trend towards regional anesthesia began in the late 1800s when William Halsted and Richard Hall experimented with cocaine as a local anesthetic for upper and lower limb procedures. Regional anesthesia of the upper limb can be achieved by blocking the brachial plexus at varying stages along the course of the trunks, divisions, cords and terminal branches. The four most common techniques used in the clinical setting are the interscalene block, the supraclavicular block, the infraclavicular block, and the axillary block. Each approach has its own unique set of advantages and indications for use. The supraclavicular block is most effective for anesthesia of the mid-humerus and below. Infraclavicular blocks are useful for procedures requiring continuous anesthesia. Axillary blocks provide effective anesthesia distal to the elbow, and interscalene blocks are best suited for the shoulder and proximal upper limb. The two most common methods for localizing the appropriate nerves for brachial plexus blocks are nerve stimulation and ultrasound guidance. Recent literature on brachial plexus blocks has largely focused on these two techniques to determine which method has greater efficacy. Ultrasound guidance has allowed the operator to visualize the needle position within the musculature and has proven especially useful in patients with anatomical variations. The aim of this study is to provide a review of the literature on the different approaches to brachial plexus blocks, including the indications, techniques, and relevant anatomical variations associated with the nerves involved.

Suprascapular nerve palsy following supraclavicular block for upper extremity surgery: report of 3 cases

Regional anesthesia has become the preferred method of anesthesia for many upper extremity operations and generally results in decreased hospital stays, postoperative opioid requirement, and postoperative nausea. Complications of regional anesthesia are rarely reported in the literature, possibly because of limited anesthesiologist-patient follow-up. Three cases of suprascapular nerve palsy after ultrasound-guided supraclavicular nerve block for routine outpatient upper extremity surgery are reported. All cases occurred in men who originally presented with shoulder pain, which resolved with time, followed by weakness in the supraspinatus and infraspinatus, which improved over time but did not resolve. One case resulted in ipsilateral phrenic nerve palsy as well. A review of the literature on the subject accompanies the report of these 3 cases.

US-guided femoral and sciatic nerve blocks for analgesia during endovenous laser ablation

PURPOSE

Endovenous laser ablation may be associated with significant pain when performed under standard local tumescent anesthesia. The purpose of this study was to investigate the efficacy of femoral and sciatic nerve blocks for analgesia during endovenous ablation in patients with lower extremity venous insufficiency.

METHODS

During a 28-month period, ultrasound-guided femoral or sciatic nerve blocks were performed to provide analgesia during endovenous laser ablation in 506 legs and 307 patients. The femoral block (n = 402) was performed at the level of the inguinal ligament, and the sciatic block at the posterior midthigh (n = 124), by injecting a diluted lidocaine solution under ultrasound guidance. After the blocks, endovenous laser ablations and other treatments (phlebectomy or foam sclerotherapy) were performed in the standard fashion. After the procedures, a visual analogue pain scale (1-10) was used for pain assessment.

RESULTS

After the blocks, pain scores were 0 or 1 (no pain) in 240 legs, 2 or 3 (uncomfortable) in 225 legs, and 4 or 5 (annoying) in 41 legs. Patients never experienced any pain higher than score 5. The statistical analysis revealed no significant difference between the pain scores of the right leg versus the left leg (p = 0.321) and between the pain scores after the femoral versus sciatic block (p = 0.7).

CONCLUSIONS

Ultrasound-guided femoral and sciatic nerve blocks may provide considerable reduction of pain during endovenous laser and other treatments, such as ambulatory phlebectomy and foam sclerotherapy. They may make these procedures more comfortable for the patient and easier for the operator.