Technical considerations for approaches to the ultrasound-guided maxillary nerve block via the pterygopalatine fossa: a literature review

The Maxillary Nerve Block in Cleft Palate Care: A Review of the Literature and Expert's Opinion on the Preferred Technique of Administration

INTRODUCTION

Although the maxillary nerve block (MNB) provides adequate pain relief in cleft palate surgery, it is not routinely used globally, and reported techniques are heterogeneous. This study aims to describe relevant anatomy and to present the preferred technique of MNB administration based on the current literature and the expert opinion of the authors.

METHOD AND MATERIALS

First, a survey was sent to 432 registrants of the International Cleft Palate Master Course Amsterdam 2023. Second, MEDLINE (PubMed interface) was searched for relevant literature on maxillary artery (MA) anatomy and MNB administration in pediatric patients.

RESULTS

Survey response rate was 18% (n=78). Thirty-five respondents (44.9%) used MNB for cleft palate surgery before the course. A suprazygomatic approach with needle reorientation towards the ipsilateral commissure before incision was most frequently reported, mostly without the use of ultrasound. Ten and 20 articles were included on, respectively, MA anatomy and MNB administration. A 47.5% to 69.4% of the MA's run superficial to the lateral pterygoid muscle and 32% to 52.5% medially. The most frequently described technique for MNB administration is the suprazygomatic approach. Reorientation of the needle towards the anterior aspect of the contralateral tragus appears optimal. Needle reorientation angles do not have to be adjusted for age, unlike needle depth. The preferred anesthetics are either ropivacaine or (levo)bupivacaine, with dexmedetomidine as an adjuvant.

CONCLUSION

Described MNB techniques are heterogeneous throughout the literature and among survey respondents and not routinely used. Further research is required comparing different techniques regarding efficacy and safety.

Suprazygomatic Maxillary Nerve Blocks and Opioid Requirements in Pediatric Adenotonsillectomy: A Randomized Clinical Trial

Importance

Pain management following pediatric adenotonsillectomies is opioid-inclusive, leading to potential complications.

Objective

To investigate the use of suprazygomatic maxillary nerve (SZMN) blocks to reduce pain and opioid use after pediatric intracapsular adenotonsillectomy and to measure recovery duration and incidence of complications.

Design, Setting, and Participants

This was a randomized, blinded, prospective single-center tertiary pediatric hospital that included 60 pediatric patients (2-14 years old) scheduled for intracapsular adenotonsillectomy from November 2021 to March 2023. Patients were excluded for having combined surgical procedures, developmental delay, coagulopathy, chronic pain history, known or predicted difficult airway, or unrepaired congenital heart disease. Participants were randomized to receive bilateral SZMN blocks (block group) or not (control group).

Intervention

SZMN block administered bilaterally under general anesthesia for intracapsular adenotonsillectomy.

Primary Outcomes and Measures

Opioid consumption, FLACC (Face, Legs, Activity, Cry, Consolability) scores, and rates of opioid-free postanesthesia care unit (PACU) stay. Secondary outcomes were recovery duration and incidence of adverse effects, ie, nausea, vomiting, block site bleeding, and emergency delirium.

Results

The study population included 53 pediatric patients (mean [SD] age, 6.5 [3.6] years; 29 [55%] females; 24 [45%] males); 26 were randomly assigned to the SZMN block group and 27 to the control group. The mean (SD) opioid morphine equivalent consumption during PACU stay was 0.15 (0.14) mg/kg for the 27 patients in the control group compared with 0.07 (0.11) mg/kg for the 26 patients in the block group (mean difference, 0.08; 95% CI, 0.01-0.15; Cohen d, 0.64). The block group had a higher incidence of opioid-free PACU stays (n = 7 patients; 58%) compared with the control group (n = 15 patients; 26%) (mean difference, 32%; 95% CI, 5%-53%). Patients in the block group experienced lower FLACC scores (0.7 vs 1.6; mean difference, 0.9; 95% CI, 0.2-1.6; Cohen d, 0.7). The overall occurrence of adverse events was similar in the 2 groups, with no reported nerve block-related complications.

Conclusions and Relevance

The results of the randomized clinical trial indicate that SZMN blocks are a useful adjunct tool for managing postoperative pain in pediatric intracapsular adenotonsillectomy. Use of these blocks during adenotonsillectomy provided clinically meaningful reductions of postoperative opioid consumption with a low risk of complications.

Trial Registration

ClinicalTrials.gov Identifier: NCT04797559.

Ultrasound-Guided Suprazygomatic Maxillary Nerve Block Is Effective in Reducing Postoperative Opioid Use Following Bimaxillary Osteotomy

BACKGROUND

Ultrasound-guided maxillary nerve block has recently been described, though its impact upon bimaxillary osteotomy has not been formally investigated.

PURPOSE

The present study was carried out to determine whether the addition of ultrasound-guided maxillary nerve block in subjects undergoing bimaxillary osteotomy reduces opioid use.

STUDY DESIGN, SETTING, SAMPLE

A randomized clinical trial was carried out in adults undergoing bimaxillary osteotomy between April 2019 and January 2020 at Teknon Medical Center (Barcelona, Spain).

PREDICTOR VARIABLE

The predictor variable was the treatment technique used (maxillary nerve block or no block). The subjects were randomized to either receive (test group) or not receive (control group) bilateral ultrasound-guided suprazygomatic maxillary nerve block (5 ml of 0.37% ropivacaine) before surgery.

MAIN OUTCOME VARIABLE(S)

The primary outcome variable was the intravenous methadone requirements in the first two postoperative hours. The secondary outcome variables were postoperative pain, rescue subcutaneous methadone, intravenous remifentanil used intraoperatively, the incidence of postoperative nausea-vomiting, and complications derived from maxillary nerve block.

COVARIATES

Subject age, sex, weight, height, and anesthetic risk, and the duration of surgery were recorded.

ANALYSES

Descriptive and inferential analyses were performed using the χ2 test and Mann-Whitney U test. Statistical significance was considered for P < .05.

RESULTS

The baseline sample consisted of 68 subjects scheduled for bimaxillary osteotomy. The follow-up sample comprised 60 subjects: 30 in the control group (10 females and 20 males, aged 34.0 ± 10.2 years) and 30 in the test group (13 females and 17 males, aged 29.8 ± 10.8 years). The subjects who received maxillary nerve block showed less intravenous methadone use in the first 2 hours postsurgery (median 2.0 mg control group vs 0 mg test group; P < .001), lower pain levels at any time during the first 18 hours postsurgery (median visual analog score 4 control group vs 2 test group; P < .001), and a lesser percentage required methadone (33.3% control group vs 0% test group; P < .01) at 4-18 hours postsurgery.

CONCLUSION AND RELEVANCE

The results obtained suggest that ultrasound-guided maxillary nerve block is a promising anesthetic technique capable of reducing intraoperative and postoperative opioid use, with greater patient comfort in bimaxillary osteotomy.

Non-Surgical Treatments of Trigeminal Neuralgia from the Perspective of a Pain Physician: A Narrative Review

Trigeminal neuralgia (TN) is a unilateral disorder characterized by electric shock-like pain, abrupt onset and termination, and limited to one or more branches of the trigeminal nerve. Various therapeutic modalities for TN have been introduced. We searched for literature indexed in PubMed, Medline, and the National Library of Medicine and reviewed all relevant articles on non-surgical treatments for TN. Published studies were reviewed with no restrictions on date; reviews, clinical trials, animal studies, retrospective studies, and cases were included. Carbamazepine and oxcarbazepine are the recommended first-line pharmacotherapies. Interventional treatments should be considered when pharmacotherapy is insufficient or withdrawn because of adverse effects.

Lateral pterygoid muscle ultrasound-guided injection: A technical note

BACKGROUND

Temporomandibular disorders (TMDs) are a frequent cause of orofacial pain, causing functional disability and a negative impact on quality of life. Botulinum toxin (BTX-A) injection in lateral pterygoid muscle (LPM) is one of the treatment modalities proposed, but the blind puncture guided by EMG carries a risk of vascular puncture or diffusion of the toxin to nearby muscles. We describe an ultrasound-guided approach and evaluate the spread of the injection in a fresh human cadaver.

METHODS

A fresh human cadaver was injected. An out-of-plane approach was performed using a convex probe, injecting 1.0 ml of 0.25% methylene blue dye into the LPM. After, a dissection was performed to isolate the lateral pterygoid muscle and assess the spread of the dye.

RESULTS

Ultrasound-guided injection allowed to visualize in real-time the spread of the dye within the LPM. The deep and superficial muscles nearby to LPM were not stained by the dye, but upper and lower head of LPM was heavily stained.

CONCLUSION

Ultrasound-guided approach for the injection of BTX-A into the LPM could be considered a successful and safe treatment for myofascial pain related to TMD. Therefore, further clinical studies are needed to study the reproducibility of ultrasound guided LPM injection and to evaluate the clinical results.

Comparison of the feasibility and safety of infrazygomatic and suprazygomatic approaches to pterygopalatine fossa using virtual reality

BACKGROUND

Injections of local anesthetics into pterygopalatine fossa gained popularity for treating acute and chronic facial pain and headaches. Injury of maxillary artery during pterygopalatine fossa injection can result in pseudoaneurysm formation or acute bleeding. We aimed to identify the optimal approach into pterygopalatine fossa by comparing feasibility and safety of suprazygomatic and two infrazygomatic approaches.

METHODS

We analyzed 100 diagnostic CT angiographies of cerebral arteries using 3D virtual reality. Each approach was determined as a target point in pterygomaxillary fissure and an array of outermost edges trajectories leading to it. The primary outcomes were feasibility and safety for each approach. The secondary outcome was the determination of maxillary artery position for each approach to identify the safest needle entry point.

RESULTS

Suprazygomatic approach was feasible in 96.5% of cases, while both infrazygomatic approaches were feasible in all cases. Suprazygomatic approach proved safe in all cases, posterior infrazygomatic in 73.5%, and anterior infrazygomatic in 38%. The risk of maxillary artery puncture in anterior infrazygomatic approach was 14.7%±26.4% compared to 7.5%±17.2%. in posterior infrazygomatic with the safest needle entry point in the upper-lateral quadrant in both approaches.

CONCLUSION

The suprazygomatic approach proved to be the safest, however not always feasible. The posterior infrazygomatic approach was always feasible and predominantly safe if the needle entry point was just anterior to the condylar process. The anterior infrazygomatic approach was always feasible, however least safe even with an optimal needle entry point just anterior to the coronoid process.

Effect of Ultrasound Image-Guided Nerve Block on the Postoperative Recovery Quality of Patients with Tibial Fractures Using the Concept of Enhanced Recovery after Surgery

This study was aimed at investigating the clinical effect of ultrasound-guided nerve block based on the concept of enhanced recovery after surgery (ERAS) for postoperative anesthesia in patients with tibial fractures. The noise-reduction processing was introduced in ultrasound images to adjust the ultrasound clarity of the patient. A total of 177 patients with tibial fractures in our hospital were retrospectively analyzed and divided into OG group (general anesthesia combined with nerve block, 78 cases), C1 group (simple general anesthesia, 27 cases), C2 group (ultrasound-guided nerve block combined with general anesthesia, 10 cases), and C3 group (62 cases of spinal-epidural anesthesia). The effect of anesthesia and postoperative recovery time of patients in each group were analyzed. The wake-up time of the OG group was significantly shorter than that of the other three groups (P < 0.05). The doses of propofol and remifentanil in the OG group were much lower than those in the other groups (P < 0.05). After the ultrasound image was processed with noise reduction, the image showed the lesion more clearly. The excellent and good rates of OG group, C1 group, C2 group, and C3 group were 89.86%, 62.73%, 75.37%, and 61.07%, respectively. The Ramsay sedation score and anesthesia satisfaction in the OG group were obviously higher than those in the other groups, but there was no significant difference (P > 0.05). The visual analogue scale (VAS) scores of the OG group at 12 h, 24 h, and 36 h after the surgery were 4.52 ± 0.41, 4.72 ± 0.24, and 4.81 ± 0.74, respectively, which were significantly higher than those of the other three groups (P < 0.05). On the basis of ERAS, ultrasound-guided nerve block combined with general anesthesia can improve the perioperative pain in patients with tibial fractures and significantly shorten the time for the wake-up time. In addition, it was safe and reliable, so it was worthy of clinical promotion.

Bilateral Sphenopalatine Ganglion Block With Liposomal Bupivacaine Followed by Severe Hypertension: A Case Report

We reviewed a case of bilateral sphenopalatine ganglion (SPG) blockade with liposomal bupivacaine for sinus surgery. The case was complicated by severe postoperative hypertension refractory to antihypertensives and needing intensive care unit (ICU) admission. While SPG blockade has been used to treat headaches and provide perioperative analgesia, this complication and a possible mechanism have not been described. We discuss how local anesthetic spread beyond the SPG may have caused prolonged parasympathetic blockade and hypertension. Before approved indications are established, we recommend avoiding the use of liposomal bupivacaine in off-label settings when the function of bilateral autonomic structures could be affected.

Application of ultrasound guidance in the oral and maxillofacial nerve block

Introduction

Nerve block technology is widely used in clinical practice for pain management. Conventional nerve localization methods, which only rely on palpation to identify anatomical landmarks, require experienced surgeons and can be risky. Visualization technologies like ultrasound guidance can help prevent complications by helping surgeons locate anatomical structures in the surgical area and by guiding the operation using different kinds of images. There are several important and complex anatomical structures in the oral and maxillofacial regions. The current article reviews the application of ultrasound guidance in oral and maxillofacial nerve blocks.

Methods

We searched the literature on the use of ultrasound guidance for the main nerve block techniques in the oral and maxillofacial regions using both PubMed and MEDLINE and summarized the findings.

Results and Discussion

A review of the literature showed that ultrasound guidance improves the safety and effectiveness of several kinds of puncture procedures, including nerve blocks. There are two approaches to blocking the mandibular nerve: intraoral and extraoral. This review found that the role of ultrasound guidance is more important in the extraoral approach. There are also two approaches to the blocking of the maxillary nerve and the trigeminal ganglion under ultrasound guidance: the superazygomatic approach and the infrazygomatic approach. The infrazygomatic approach can be further divided into the anterior approach and the posterior approach. It is generally believed that the anterior approach is safer and more effective. This review found that the effectiveness and safety of most oral and maxillofacial nerve block operations can be improved through the use of ultrasound guidance.

Current advances and novel research on minimal invasive techniques for musculoskeletal disorders

The present review summarized the current advances and novel research on minimal invasive techniques for musculoskeletal disorders. Different invasive approaches were proposed in the physical therapy field for the management of musculoskeletal disorders, such as ultrasound-guided percutaneous needle electrolysis, dry needling, acupuncture and other invasive therapy techniques, discussing about their worldwide status, safety and interventional ultrasound imaging. Indeed, dry needling may be one of the most useful and studies invasive physical therapy applications in musculoskeletal disorders of different body regions, such as back, upper limb, shoulder, arm, hand, pelvis, lower limb, neck, head, or temporomandibular joint, and multiple soreness location disorders, such as fibromyalgia. In addition, the assessment and treatment by acupuncture or electro-acupuncture was considered and detailed for different conditions such as plantar fasciitis, osteoarthritis, spasticity, myofascial pain syndrome, osteoporosis and rheumatoid arthritis. As an increasing technique in physical therapy, the use of ultrasound-guided percutaneous needle electrolysis was discussed in injuries of the musculoskeletal system and entrapment neuropathies. Also, ultrasound-guided percutaneous neuromodulation was established as a rising technique combined with ultrasound evaluation of the peripheral nerve system with different clinical applications which need further studies to detail their effectiveness in different musculoskeletal conditions. Thus, invasive physical therapy may be considered as a promising approach with different novel applications in several musculoskeletal disorders and a rising use in the physiotherapy field.

Images in anesthesiology: three safe, simple, and inexpensive methods to administer the sphenopalatine ganglion block

The sphenopalatine ganglion (SPG) block is a simple and valuable technique that was discovered over a century ago, but, unfortunately, very few anesthesiology providers are familiar with this block. After some of our recent publications, physicians from different countries have reached out to us requesting more specifics on how we perform our version of the block. In this report, we provide a brief history of the block and demonstrate our three effective, simple, readily available, and inexpensive methodologies with images. We are proud to share that our three SPG block techniques have so far effectively relieved patients of chronic migraines, acute migraines, tension headaches, moderate-to-severe back pain, and post-dural puncture headaches.