Anuj Bhatia

Development and Validation of a New Technique for Ultrasound-guided Stellate Ganglion Block

Background and Objectives: Although the stellate ganglion is located anteriorly to the first rib, anesthetic block is routinely performed at the C6 level. Ultrasonography allegedly improves accuracy of needle placement and spread of injectate. The technique is relatively new, and the optimal approach has not been determined. Moreover, the location of the cervical sympathetic trunk relative to the prevertebral fascia is debatable. Methods: Three-dimensional sonography was performed on 10 healthy volunteers, and image reconstruction was completed. On the basis of analysis of pertinent anatomy, a lateral trajectory for needle placement was simulated. Accuracy was tested by injection of methylene blue in cadavers. A clinical validation study was then conducted. A block needle was inserted according to the predetermined lateral path, and 5 mL of a mixture of bupivacaine and iohexol was injected. Spread of the contrast agent was verified fluoroscopically. Results: Image reconstruction revealed that the cervical sympathetic trunk is located posterolaterally to the prevertebral fascia on the surface of the longus colli muscle. The mean anteroposterior width of the muscle at the C6 level was 11 mm. The lateral approach does not interfere with any visceral or nerve structures. Anatomic dissection in cadavers confirmed entirely subfascial spread of the dye and staining of the sympathetic trunk. The contrast agent spread was seen in all patients between the C4 and T1 levels in a typical prevertebral pattern. Conclusions: This study revealed that, at the C6 level, the cervical sympathetic trunk lies entirely subfascially. Subfascial injection via the lateral approach ensures reliable spread of a solution to the stellate ganglion.

Prophylactic Dexamethasone for Postoperative Nausea and Vomiting in Pediatric Strabismus Surgery: A Dose Ranging and Safety Evaluation Study

In this double-blind, randomized, placebo-controlled study, we evaluated the efficacy and safety of different doses of prophylactic IV dexamethasone for postoperative nausea and vomiting (PONV) in 168 children (aged 2–15 yr) scheduled for strabismus surgery. Patients received IV dexamethasone 0.25 mg/kg (D 0.25), 0.5 mg/kg (D 0.5), 1.0 mg/kg (D 1), or saline (S) immediately after induction of general anesthesia. Patients were discharged 24 h after surgery. Nausea and vomiting were assessed at 0–2, 2–6, and 6–24 h after surgery. Blood glucose was measured preoperatively and at 4 h after study drug administration. Wound healing and infection were assessed after 1 wk. More patients in group S had vomiting at 0–2, 2–6, and 6–24 h (P = 0.001, P = 0.003, and P = 0.04, respectively) and required larger doses of rescue antiemetics compared with the dexamethasone groups. Fewer patients in the dexamethasone groups (6, 3, and 6 in D 0.25, D 0.5, and D 1, respectively) had severe PONV compared with group S (P = 0.001). No significant increase in postoperative blood glucose levels was observed and wound healing was satisfactory in all four groups. The results suggest that dexamethasone 0.25 mg/kg is more effective than saline and equally effective compared with larger doses for preventing PONV for pediatric strabismus surgery.

Case report: pneumothorax as a complication of the ultrasound-guided supraclavicular approach for brachial plexus block.

In this case report, we are the first to describe the occurrence of a pneumothorax after ultrasound-guided supraclavicular block. The block was performed using a medial-to-lateral in-plane needle insertion technique. The predisposing operator, technical, and patient factors as well as strategies for preventing this uncommon yet potentially severe complication are discussed.

Circulatory collapse after topical application of vancomycin powder during spine surgery.

A hypersensitivity reaction, either anaphylactic or anaphylactoid, is a well-known adverse effect following intravenous and oral administration of vancomycin. The authors report a case of circulatory collapse and its management after the topical application of vancomycin powder during spinal instrumentation surgery. A 52-year-old woman with breast cancer and metastasis to her spine underwent a vertebrectomy of the T-10 vertebra with instrumented reconstruction from T-8 to T-12. The patient was hemodynamically stable during most of the procedure despite a 2-L blood loss requiring administration of crystalloids, colloids, packed red blood cells, and fresh-frozen plasma. During closure of the subcutaneous layer, there was a sudden drop in blood pressure from 120/60 to 30/15 mm Hg and an increase in heart rate from 95 to 105 bpm. No skin erythema or rash was visible, and there was no bronchospasm or increase in airway pressure. The patient was treated with fluids, boluses of ephedrine, phenylephrine, and adrenaline. The operation was completed and the patient woke up neurologically intact but did require blood pressure support with a norepinephrine infusion for the next 4 hours. She was discharged from hospital in a good clinical state on the 4th postoperative day. It was speculated that the rapid absorption of vancomycin powder applied on the surgical wound caused an anaphylactoid reaction and the circulatory collapse. With an increase in the use of topical vancomycin in surgical wounds, communication and awareness among all intraoperative team members is important for rapid diagnosis of an adverse reaction and for appropriate management.

Randomized controlled trial comparing pudendal nerve block under ultrasound and fluoroscopic guidance.

Background Although fluoroscopy is an established imaging modality for pudendal nerve block, ultrasound (US) technique allows physicians better visualization of anatomic structures. This study aimed to compare the effectiveness and safety between the US- and fluoroscopy-guided techniques. Methods A randomized, single-blind, split-plot design was used to conduct the study. Twenty-three patients undergoing bilateral pudendal nerve blocks received US-guided injections to either the left or right side, whereas the contralateral side received a fluoroscopic-guided injection in randomized sequence. Injections consisted of 4 mL of 0.5% bupivacaine and 40 mg methylprednisone. The primary outcome was the success of the block in the distribution of the pudendal nerve along the perineum, rated as either absent, moderate, or strong. Secondary outcomes were the time to administer the blocks, quality of visualization of anatomic structures using US and fluoroscopy, distance of the final US-guided needle position from the ischial spine, and incidence of adverse effects. Results No differences in the degree of neural blockade were noted between US- or fluoroscopic-guided techniques for either temperature or pinprick blockade. Time to complete the procedure was significantly longer using US compared with fluoroscopy (219 [SD, 65] and 428 [SD, 151] secs, P < 0.0001). No significant differences were noted regarding the occurrence of adverse effects between the 2 techniques. Conclusions Ultrasound-guided pudendal nerve blockade is as accurate as fluoroscopically guided injections when performed by an experienced clinician. However, the former took a longer time to perform.

Needle to nerve proximity: what do the animal studies tell us?

Recent animal studies have provided insight and understanding, as well as promising clinical tools, to help identify needle-to-nerve contact and potentially hazardous intraneural injection. This narrative review describes and summarizes the contemporary animal studies primarily relating to indicators of needle-to-nerve contact and intraneural injection. Resultant nerve injury, whenever sought, is discussed.

Review article: is ultrasound guidance advantageous for interventional pain management? A systematic review of chronic pain outcomes.

BACKGROUND:Modern ultrasound (US) is an attractive alternative to anatomical landmark-, nerve stimulation-, and fluoroscopic-guided techniques for interventional procedures performed to treat chronic pain syndromes. METHODS:In this review, we evaluated the effects of US guidance compared with traditional guidance techniques on performance, efficacy, and safety outcomes for interventional chronic pain procedures. We identified 46 studies, including 41 case series and 5 randomized trials of intermediate-to-good quality that investigated the use of US guidance for a diverse variety of chronic pain procedures. RESULTS:Our results suggest that US guidance can match or improve performance- and safety-related outcomes compared with many anatomic landmark-, nerve stimulation-, and fluoroscopic-guided techniques for treating chronic pain. CONCLUSIONS:There are presently insufficient data to support improved efficacy with procedures performed with US guidance for relieving both short- and long-term chronic pain.

Selective Cannabinoids for Chronic Neuropathic Pain: A Systematic Review and Meta-analysis

BACKGROUND: There is a lack of consensus on the role of selective cannabinoids for the treatment of neuropathic pain (NP). Guidelines from national and international pain societies have provided contradictory recommendations. The primary objective of this systematic review and meta-analysis (SR-MA) was to determine the analgesic efficacy and safety of selective cannabinoids compared to conventional management or placebo for chronic NP. METHODS: We reviewed randomized controlled trials that compared selective cannabinoids (dronabinol, nabilone, nabiximols) with conventional treatments (eg, pharmacotherapy, physical therapy, or a combination of these) or placebo in patients with chronic NP because patients with NP may be on any of these therapies or none if all standard treatments have failed to provide analgesia and or if these treatments have been associated with adverse effects. MEDLINE, EMBASE, and other major databases up to March 11, 2016, were searched. Data on scores of numerical rating scale for NP and its subtypes, central and peripheral, were meta-analyzed. The certainty of evidence was classified using the Grade of Recommendations Assessment, Development, and Evaluation approach. RESULTS: Eleven randomized controlled trials including 1219 patients (614 in selective cannabinoid and 605 in comparator groups) were included in this SR-MA. There was variability in the studies in quality of reporting, etiology of NP, type and dose of selective cannabinoids. Patients who received selective cannabinoids reported a significant, but clinically small, reduction in mean numerical rating scale pain scores (0–10 scale) compared with comparator groups (−0.65 points; 95% confidence interval, −1.06 to −0.23 points; P = .002, I2 = 60%; Grade of Recommendations Assessment, Development, and Evaluation: weak recommendation and moderate-quality evidence). Use of selective cannabinoids was also associated with improvements in quality of life and sleep with no major adverse effects. CONCLUSIONS: Selective cannabinoids provide a small analgesic benefit in patients with chronic NP. There was a high degree of heterogeneity among publications included in this SR-MA. Well-designed, large, randomized studies are required to better evaluate specific dosage, duration of intervention, and the effect of this intervention on physical and psychologic function.

Comparison of Fluoroscopy and Ultrasound Guidance for Sacroiliac Joint Injection in Patients with Chronic Low Back Pain.

Sacroiliac joint (SIJ) arthritis is a common cause of chronic mechanical low back pain (LBP) that is often treated with injection of local anesthetic and steroids. Ultrasound (US) has emerged as a viable alternative to fluoroscopy (FL) to guide SIJ injections; however, few studies have compared these modalities. In this prospective randomized, controlled trial, we compared both accuracy and efficacy of US and FL guidance for SIJ injections.

Transforaminal Epidural Steroid Injections for Treating Lumbosacral Radicular Pain from Herniated Intervertebral Discs: A Systematic Review and Meta-Analysis.

BACKGROUND:Steroids often are administered into the epidural space through the transforaminal epidural (TFE) route to treat lumbosacral radicular pain secondary to herniated intervertebral discs. However, their efficacy and safety compared with transforaminal epidural local anesthetics (LAs) or saline injections is unclear. METHODS:We reviewed randomized controlled trials that compared TFE injections of steroids (with or without LA) with LA or saline in adult outpatients with lumbosacral radicular pain secondary to herniated intervertebral disks. Databases searched included MEDLINE, EMBASE, Cochrane central register of controlled trials, Cochrane database of systematic reviews, and Google Scholar up to February 2015. Data on scores of numerical rating scale for pain, validated scores for measuring physical disability and quality of life, and incidence of surgery measured at 1 month to 2 years after the interventions were meta-analyzed. Strength of evidence was classified with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. RESULTS:Eight randomized controlled trials including 771 patients (366 in steroid and 405 in comparator groups) were included. There was variability in the studies in the dose of TFE steroids, frequency, and number of procedures. Patients who received TFE steroids reported a significant, but clinically modest, reduction in mean pain scores (0–10 scale) compared with LA/saline (−0.97 points; 95% confidence interval, −1.42 to −0.51 points; P < 0.0001, I2 = 90%; GRADE weak recommendation; moderate-quality evidence) at 3 months after the interventions. TFE steroids did not decrease physical disability at 1 to 3 months after the intervention (GRADE strong recommendation ↓; high-quality evidence) or incidence of surgery at 12 months after the intervention (GRADE strong recommendation ↓; moderate-quality evidence) compared with LA/saline. CONCLUSIONS:TFE steroids provide modest analgesic benefit at 3 months in patients with lumbosacral radicular pain secondary to herniated intervertebral disks, but they have no impact on physical disability or incidence of surgery. There was a high degree of heterogeneity among the publications included in this meta-analysis. Well-designed, large, randomized studies are required to evaluate appropriate dosages, adverse effects, number of procedures, and the effect of this intervention on psychological disability and quality of life.