Nerve Block Research Articles

Comparison of ultrasound-guided fascia iliaca compartment block versus the combined obturator nerve and adductor canal block application in postoperative analgesia for patients undergoing arthroscopic knee surgery

Background: Arthroscopic knee surgery is a surgical intervention that is frequently performed by orthopedic clinics and new studies are constantly carried out by anesthetists to ensure effective pain control. This study aimed to compare the efficacy of ultrasound-guided suprainguinal fascia iliaca compartment block (FICB) versus the combined adductor canal and obturator nerve block application in terms of postoperative analgesia in patients undergoing arthroscopic knee surgery under spinal anesthesia.Materials and Method: Sixty patients, who underwent arthroscopic knee surgery under elective conditions were included in the study. They were randomly divided into two groups, Group 1 (n=30) and Group 2 (n=30), using a lottery method. Patients operated under spinal anesthesia received ultrasound-guided suprainguinal fascia iliaca compartment block (FICB) for Group 1. The combined adductor canal and obturator nerve block for Group 2 at the end of the surgery. Intravenous patient-controlled analgesia (PCA) device containing tramadol was connected to all patients in both groups, and they were evaluated for Visual Analog Scale (VAS) scores at 0, 2, 4, 12, and 24 hours of ward follow-up. The amount of PCA used at 24 hours, additional analgesic use, development of side effects, mobilization capabilities, and satisfaction levels were assessed at the end of 24 hours.Results: There were no significant differences between the groups in terms of demographic characteristics and the type of surgery performed (p>0.05). In Group 1, where fascia iliaca block was applied the block administration time was observed to be significantly shorter compared to Group 2 (p<0.05). No significant differences were observed between the two groups in terms of postoperative VAS scores, PCA usage amounts, incidence of side effects, postoperative mobilization abilities, and satisfaction measures (p>0.05).Conclusions: Ultrasound-guided fascia iliaca compartment block alone can be effectively applied for postoperative analgesia in patients undergoing arthroscopic knee surgery, instead of combined adductor canal and obturator nerve block.

Upper Airway Block Using Lidocaine Nebulisation Versus Targeted Nerve Block for Awake Fibre-Optic Intubation in Patients with Head and Neck Burns: A Randomised Controlled Trial

Background: A difficult airway is a scenario in which an adequately trained anesthesiologist faces challenges with mask ventilation, endotracheal intubation, or both. Various anesthetic techniques have been proposed to prepare adequately for awake flexible fiber-optic intubation (AFOI), including nerve blocks for the upper airway, topical anesthesia via a specialized cannula, and lidocaine nebulization (LN). Proper anesthesia of the upper airway is crucial for successful AFOI. Objectives: This study aimed to evaluate the efficacy of airway block (AB) by LN compared to traditional upper AB techniques. Methods: This prospective, randomized, single-blinded study was conducted on 100 patients with head and neck burns scheduled for reconstructive surgery. Participants were randomly assigned to two groups of 50 patients each. In the AB group, AFOI was performed following an AB, while in the LN group, AFOI was performed 30 minutes after LN. The primary outcome measured was the time to successful awake nasal fiber-optic intubation. Secondary outcomes included the number of failed attempts and the revised nonverbal pain scale score. The time to successful awake nasal fiber-optic intubation showed no significant difference between the two groups. Results: Although the AB group had a higher number of failed attempts compared to the LN group, statistical analysis revealed no significant difference. Additionally, there was no significant difference in hemodynamic parameters between the groups. Conclusions: Both AB and LN are effective for awake nasal fiber-optic intubation, with comparable intubation times. However, LN offers a less invasive alternative.

Low-dose add-on methadone for cancer pain management: a retrospective analysis of 102 Japanese patients.

Methadone was introduced in 2013 for the treatment of intractable cancer pain in Japan and is indicated for patients receiving opioid doses ≧60mg/day as an oral morphine equivalent. Low-dose (≦10mg/day) add-on methadone to prior opioids has been reported from European countries to successfully relieve various types of intractable cancer pain; however, there are few reports of such use in Japan. The aim of this study was to analyze more than a hundred cases with low-dose add-on methadone to treat intractable pain in Japanese cancer patients. All cases in which 5 or 10mg/day of methadone was added to prior opioids by the Palliative Care Team or Division of Palliative Medicine in our hospital during the period between April 2016 and September 2023 were extracted and analyzed retrospectively on electrical medical charts. A total of 102 cases were extracted with a male-to-female ratio of60:42, and the age (mean±SD) was 62.8±14.7years old. Methadone was introduced in an inpatient setting to 86 patients. The major pathologies that caused intractable pain were spinal metastases in 48, pelvis or pelvic floor lesions in 29 and pleural and/or chest wall lesions in 16. The most common mechanism of pain was the mixture of somatic and neuropathic components. The major opioids administered prior to methadone included tapentadol in 46 patients, hydromorphone in 36 and oxycodone in 19. The dose of the prior opioids [median, (interquartile range: IQR)] was 97, (62.8-167.3) (range: 15-1313) mg/day of oral morphine equivalent. Radiotherapy, chemotherapy and nerve blocks were performed as concomitant therapies in 48, 22 and 11 patients, respectively (with some overlap). The number of rescue doses [median (IQR)] was significantly decreased from three (two to five) on the day before methadone to one (zero to four) after seven days from methadone initiation. The side effects leading to discontinuation of methadone were drowsiness in three cases, nausea in three cases and dizziness in one case (with some overlap). Compared with complete switching from other opioids, low-dose add-on methadone can reduce the possibility of major dose discrepancies and can be quickly adjusted by combined opioid reduction/increase. Low-dose add-on methadone can be an effective and safe method for intractable cancer pain.

Evaluation of Pectoral Nerve Blocks Type II (PEC II) for Augmentation Mammoplasty: Prospective, Randomized, and Double-Blind Study

Objective: to study the effectiveness of type II pectoral nerve block (PEC II) for breast augmentation with submuscular implants by assessing opioid consumption and pain scale in the immediate postoperative period, from the post-anesthesia care unit (PACU) to 24 h postoperatively. Methods: A prospective, controlled, randomized, and double-blind study. Thirty-four patients were analyzed during the perioperative period and in the PACU, with one group receiving bilateral PEC II combined with general anesthesia and the control group receiving only general anesthesia. Results: There was no difference between the groups regarding demographic data, surgical and anesthetic times, or intraoperative opioid use. Opioid consumption in the control group was consistently higher at all the time intervals studied, with an average morphine consumption 38.7% greater. The largest variation in morphine consumption occurred at the fourth and sixth hours postoperatively. The greatest difference in postoperative pain was 36% higher in the control group compared to the intervention group. Conclusions: patients who underwent general anesthesia combined with PEC II had lower opioid consumption and a lower postoperative pain score without associated complications, confirming the effectiveness of the procedure.

Effect of Lingual Nerve Block and Localised Somatosensory Abnormalities in Patients With Burning Mouth Syndrome-A Randomised Crossover Double-Blind Trial.

To investigate the effect of a lingual nerve block on spontaneous pain in patients with burning mouth syndrome (BMS) and to estimate associated somatosensory abnormalities by quantitative sensory testing (QST). A standardised QST battery including cold detection threshold (CDT), warmth detection threshold (WDT), thermal sensory limen (TSL), paradoxical heat sensation (PHS), cold pain threshold (CPT), heat pain threshold (HPT), mechanical pain threshold (MPT), wind-up ratio (WUR) and pressure pain threshold (PPT) was performed at the oral mucosa of the most painful site and intraoral control site in 20 BMS patients, and at the tongue and cheek mucosa in 22 age- and gender-matched healthy controls. The effect of a lingual nerve block on spontaneous burning pain reported by the BMS patients on a 0-10 cm visual analogue scale (VAS) was investigated in a randomised double-blind crossover design using (1 mL) lidocaine (lido) or saline (sal) with an interval of 1 week. The BMS patients were grouped into 'central' and 'peripheral' mechanisms based on the effect of the lingual nerve injections. For each BMS patient, Z-scores and Loss/Gain scores were computed. Differences among groups and sites were analysed using a two-way ANOVA. Differences within group were assessed by paired t-test. The 20 BMS patients were characterised on the basis of VAS changes (ΔLido-ΔSal) as a peripheral BMS subgroup (n = 9) with pain relief more than 1 cm on the VAS and a central BMS subgroup (n = 11) with pain relief less than 1 cm. BMS patients (n = 20) had lower sensitivity to thermal stimuli (i.e., CDT, WDT, TSL, CPT, HPT and PPT) and higher sensitivity to mechanical stimuli (i.e., PPT) compared with controls (p ≤ 0.007). Based on Loss/Gain coding, L1G0 (loss of thermal somatosensory function with no somatosensory gain, 55.0%) was the most frequent coding in the BMS group, which was higher than 11.4% in the control group (p < 0.001). Surprisingly, there was no significant difference between the peripheral and central BMS subgroups with regard to the Z-scores of any of the nine QST parameters (p > 0.097). The results of the lingual nerve blocks demonstrated two distinct phenotypes with either peripheral or central mechanisms but no direct impact on somatosensory function. Overall, somatosensory function in BMS patients seems abnormal in the painful areas compared to matched controls with a conspicuous loss of thermosensory function.

Conditioned Pain Modulation Differences in Central and Peripheral Burning Mouth Syndrome (BMS) Patients.

To evaluate conditioned pain modulation (CPM) in burning mouth syndrome (BMS) patients with different pain mechanisms. Twenty BMS patients (52.0 ± 6.8 years, 17 women and 3 men) and age- and gender-matched 22 healthy controls were enrolled in this randomised controlled trial. The patients received an active lingual nerve block (lidocaine) and a placebo injection (saline) randomly with an interval of 1 week in a double-blinded manner. Patients evaluated their pain intensity on a 0- to 10-cm visual analogue scale (VAS) before and after each injection, with or without CPM. Based on the anaesthesia effect, BMS patients were divided into two groups with presumed different pain mechanisms; a 'central subgroup (n = 11)' with pain relief less than 1 cm and 'peripheral subgroup (n = 9)' with pain relief more than 1 cm on the VAS. Mechanical pain threshold (MPT) and wind-up ratio (WUR) were investigated at two oral mucosa regions: the region with most intense symptoms and a control region for the patient group; tongue and buccal region for the control group. CPM was induced by immersing the left hand into cold water. A moderate level of pain (around five on the VAS) was obtained by adjusting the water temperature. MPT and WUR were measured twice for all the participants with and without CPM, which was analysed and presented as relative change in MPT and WUR. Differences between groups were analysed using two-way ANOVA. Differences within group between tests were assessed by paired t-test. At baseline, there were no significant group differences for MPT or WUR between BMS patients and healthy controls (p ≥ 0.156). The mean bath temperature to evoke moderate pain for the BMS group was significantly lower than that for the healthy control group (8.9°C vs. 11.9°C, p = 0.003). The CPM evoked an inhibitory modulation in 18.2%-44.4% of BMS patients, while for the healthy group, the ratio was 68.2%-81.8%. Central BMS patients had smaller CPM effects than healthy participants at the painful site and control site, which indicated a decreased CPM function (p ≤ 0.034). Peripheral BMS patients had lower CPM effects than healthy participants only at the painful site (p = 0.037). The present findings documented impairment of central nociceptive inhibition processing in BMS patients which was more extensive in central BMS than peripheral BMS. These findings add to the suggestion that BMS may a heterogeneous pain condition with at least two different phenotypes.

Practice and challenges related to regional anesthesia in Amhara regional hospitals, Northwest-Ethiopia: a web-based survey study

BackgroundRegional anesthesia (RA) can improve patient outcomes and reduce perioperative complications including deaths. Despite its benefits, RA is less utilised in low-resource settings. The purpose of this study was to assess practice and challenges related to RA in Amhara Regional Hospitals, Northwest-Ethiopia.MethodsA web- based survey was distributed among 360 anesthetists working in Amhara Regional Hospitals, Northwest-Ethiopia from November 15 - January 30, 2023. An English, semi-structure, self-administered questionnaire was disseminated by email and telegram following ethical clearance. The survey included questions about the use of RA, socio-demographic characteristics of anesthetist, types of practiced regional blocks, and barriers to perform RA. All volunteer respondents who filled online questionnaire during study period were included. The data were coded and analyzed using statistical package for social Sciences (SPSS) software-version 20. Both inferential and descriptive statistics were used to describe the results.ResultsThe overall response rate was 63.3% (223 out of 360 completed surveys). A total of 132 respondents (36.7%) did not provide a response, and 5 respondents (1.4%) submitted incomplete) surveys. The most frequently self-reported barriers to performing peripheral nerve blocks were a lack of equipment (regional procedure kit including block needle, ultrasound, nerve stimulator, or epidural set) 185 (82.9%), lack of knowledge 171(76.7%), lack of practical skills 112 (50.2%), and lack of drugs/medication 50 (22.4%).ConclusionsThe principal findings indicate that all respondents perform spinal anaesthesia, while the practice of peripheral RA varies. Reported barriers to performing RA are related to knowledge and training, as well as a lack of equipment (there aren’t enough regional procedure kits available that include an epidural set, block needle, nerve stimulator, and ultrasound). A more stringent approach with specific requirements, distinguishing between neuraxial and peripheral blocks, enhance training opportunities for peripheral nerve blocks are required in Ethiopia.

Effectiveness of ultrasound-guided ilioinguinal and iliohypogastric nerve block in pediatric inguinal hernia surgery: a systematic review and meta-analysis of randomized controlled trials

Aim: To evaluate the efficacy of ultrasound-guided ilioinguinal and iliohypogastric nerve block (IIHB) in children undergoing surgery for inguinal hernias.Material and methods: PubMed, Embase, Cochrane Library, and Web of Science databases were searched to January 4, 2024. For continuous data, the effect sizes were presented as weighted mean differences (WMDs), and for categorical data, they were reported as relative ratios (RR), each accompanied by 95% confidence intervals (CIs).Results: IIHB demonstrated a longer duration before the need for the first analgesic compared to transverse abdominis plane (TAP), caudal epidural block (CEB), and pre-incisional wound infiltration (PWI), but a shorter duration than quadratus lumborum block (QLB). The IIHB group had a higher probability of requiring rescue analgesics compared to other blocks or PWI (RR: 1.69, 95% CI: 1.25 to 2.28, p=0.001). Higher FLACC scores were noted at 12 hours for the IIHB group (WMD:0.50, 95% CI: 0.13 to 0.86, p=0.008). IIHB required more intraoperative fentanyl compared to controls (RR: 2.14, 95% CI:1.17 to 3.92, p=0.014).Conclusion: While IIHB may have some benefits, it does not appear to be more effective overall in managing postoperative pain in pediatric inguinal hernia surgery patients compared to other blocks or PWI.

Evaluation of the Rostral Inferior Alveolar Nerve Block via the Mental Foramen in Equids: In Vivo Efficacy Testing.

The use of proper sedative and regional anesthetic protocols is essential when performing equine dental surgical procedures under standing sedation. The efficacy of the rostral inferior alveolar nerve block via the mental foramen has not been previously studied. Aims of this study included determining the efficacy of the block, investigating whether any region (labial mucosa, alveolar mucosa, or teeth) was more reliably anesthetized, and if differences in efficacy existed between bilateral and unilateral blocks. In this blinded trial, 10 horses each were randomly assigned to receive a left unilateral block, right unilateral block or bilateral blocks and 5 horses were bilateral controls. For unilateral groups, the contralateral side of the horse acted as its own unilateral control. Mechanical nociceptive stimulus methods were used to determine response to stimulus at time points pre-sedation, post-sedation, and post-injection at 10, 30, 60, and 90 min. Results were evaluated in 4 groups: unilateral blocks, unilateral controls, bilateral blocks and bilateral controls. Overall, all groups were significantly less likely to respond to stimulus at time points post-sedation, T10, and T30, whereas only blocked sites were less likely to respond at T60 and T90 compared to pre-sedation. There was no significant difference in response to stimuli of blocked sites between the 3 regions at all time points. Overall, at T60 and T90, blocks produced regional anesthesia in 73% and 55% of sites, respectively. This study demonstrated the equine mental foramen regional nerve block has varied efficacy, producing partial or incomplete regional anesthesia in some cases.

The Scalp Nerve Block Combined with Intercostal Nerve Block Improves Recovery After Deep Brain Stimulation in Patients with Parkinson's Disease: A Prospective, Randomized Controlled Trial.

To explore the effect of scalp nerve block (SNB) combined with intercostal nerve block (ICNB) on quality of recovery (QoR) after deep brain stimulation (DBS) in patients with Parkinson's disease (PD). We conducted a prospective randomized controlled trial in which 88 patients with PD were randomly assigned to undergo SNB combined with ICNB (SNB group) or not (control group) before surgery. The primary outcome was the 15-item QoR (QoR-15) score 24h after surgery. The secondary outcomes included QoR-15 scores at 72h and 1 month after surgery, pain-related events, recovery events in post-anesthesia care unit (PACU), duration of anesthesia and surgery, and nerve block-related adverse events. The QoR-15 score at 24h after surgery was significantly higher in SNB group than Control group: 122.0 ± 7.6 vs 113.5 ± 11.3 (P = 0.006). SNB combined with ICNB improved QoR-15 scores at 72h (P = 0.004) but not at 1 month after surgery (P = 0.230). The SNB group was positively related to QoR-15 scores 24h after surgery (β = 8.92; 95% CI = 4.52~13.32) after adjusting for confounding variables. The numeric rating scale pain scores at PACU discharge and at 24h, intraoperative opioid consumption, rescue analgesic use, and the incidence of postoperative nausea and vomiting (PONV) in SNB group were significantly lower than Control group (P < 0.05). Preoperative SNB combined with ICNB improved QoR and analgesia after surgery, and reduced intraoperative opioid consumption and the incidence of PONV in patients with PD who underwent DBS.

Effect of pericapsular nerve block on the quality of recovery after shoulder arthroscopy.

Shoulder arthroscopy, a standard orthopedic procedure, often results in severe postoperative pain, leading to high opioid consumption and delayed recovery. Various analgesic methods, including peripheral nerve blocks, manage this pain. The pericapsular nerve group block is a relatively new technique whose efficacy in shoulder surgeries has yet to be extensively studied. This study aimed to assess the impact of the pericapsular nerve group block on postoperative recovery quality following shoulder arthroscopy, as measured by the Quality of Recovery-15 score. A randomized, prospective, controlled, multicenter study was conducted with 60 patients undergoing unilateral shoulder arthroscopy. Participants were allocated to either Group P (patients receiving the pericapsular nerve group block and multimodal analgesia) or Group C (patients receiving only multimodal analgesia). The primary outcome measured was the Quality of Recovery-15 score 24 hours post-surgery. Secondary outcomes included postoperative numeric rating scale scores, the requirement for rescue analgesia, time to first rescue analgesia, postoperative complications, the necessity for antiemetics, and patient satisfaction. The median Quality of Recovery-15 score was significantly higher in Group P compared to Group C (120±10 vs. 89±11; P<0.001). Additionally, Group P exhibited lower pain scores at rest and during movement, a decreased need for rescue analgesia, and an extended duration before the first rescue analgesia was required. Postoperative nausea and vomiting were less common in Group P, and patient satisfaction scores were notably higher in this group. The pericapsular nerve group block significantly enhances postoperative recovery quality, reduces pain and opioid consumption, and improves patient satisfaction without significant complications.

Ultrasound-guided popliteal sciatic nerve block for surgical anesthesia in wound care patients with ongoing anticoagulant/antiaggregant therapy: A single-center, prospective study.

Ultrasound-guided peripheral nerve blocks may be a good alternative in patients under antithrombotic drugs. We evaluated the efficacy of ultrasound-guided popliteal sciatic nerve block in patients undergoing lower extremity wound debridement of whom antithrombotic drugs could not be stopped. We focused on hemorrhagic complications related to sciatic nerve block. Wound care patients followed by Cardiovascular Surgery Department scheduled for lower extremity wound surgery were included in this prospective observational study. Data was collected between March 2021 and September 2022. All patient were under antithrombotic therapy and discontinuation of anticoagulant drugs were not possible. Single-insertion and multiple-injection sciatic nerve block at popliteal region was applied to all patients under ultrasound guidance. Primary outcome was the rate of hemorrhage. Secondary outcomes were block onset times, block success and postoperative analgesia times. Data of 105 patients was evaluated, 87 were male and 18 were female. Mean patient age was 61.92 ± 10.06, mean patient body mass index was 25.68 ± 6.33. All patients were under 1 or more antithrombotic drugs. Only one minor hematoma was detected by postoperative ultrasonography control in 1 patient. Hemorrhage complication rate was 1 of 105 (% 0.95, 95% CI, 0.00024-0.051). Overall block success rate was 99.05%. Mean block onset time was 16.27 ± 5.69 minutes. Mean postoperative analgesia time was 19.5 ± 11.22 hours. Sciatic nerve block under ultrasound guidance using in-plane technique was safe and provided sufficient surgical anesthesia and postoperative analgesia for lower extremity wound debridement surgery in patients on antithrombotic drugs.

Ultrasound-guided proximal radial, ulnar, median and musculocutaneous (RUMM) nerve block in rabbit (Oryctolagus cuniculus) cadavers: medial vs lateral approach

Ultrasound-guided proximal radial, ulnar, median and musculocutaneous (RUMM) nerve block in rabbit (Oryctolagus cuniculus) cadavers: medial vs lateral approach

Ocular complications associated with inferior dental nerve block: a systematic review.

SUMMARYOcular complications associated with anesthesia of the lower dental nerve may arise during or after administration of the local anesthetic, whether temporary or permanent. This situation generates concern for both the clinician and the patient. The purpose of this article is to identify ocular complications related to lower dental nerve block, analyzing signs, symptoms, gender, age, type of procedure, and duration of complications. MethodsIn September 2023, we conducted a systematic review using various databases, such as PubMed, ScienceDirect, and Google Scholar, using relevant search terms. There were no restrictions on the date or language of the articles. ResultsWe identified 39 articles that met the selection criteria, covering an analysis of 45 cases. Complications showed a higher incidence in women, with 65.11%, compared to 34.8% in men. The most frequent ocular complications reported were diplopia (44%), amaurosis (28%) and eyelid ptosis (17.77%). ConclusionsOcular complications related to lower tooth nerve block are rare, but they can occur. A higher incidence is observed in women than in men, and there is no specific age that predominates in its appearance. Diplopia is the most common ocular complication, followed by amaurosis, eyelid ptosis, and blurred vision. These complications may manifest during the infiltration of the anesthetic, immediately after the procedure, or a few hours later.

Description of an ultrasound-guided maxillary nerve block in dogs: a cadaveric study and case series

Description of an ultrasound-guided maxillary nerve block in dogs: a cadaveric study and case series

Evaluation of Cold and Electric Pulp Tests for Assessing the Success of Inferior Alveolar Nerve Block for Mandibular First Molars diagnosed with Symptomatic Irreversible Pulpitis

IntroductionFear of dentistry, often due to past painful experiences, is a significant barrier preventing patients from visiting dentists. Achieving effective pain control, especially during root canal treatments, is crucial. However, inferior alveolar nerve blocks (IANB) have a low success rate, influenced by factors such as anxiety, anatomical variations, and technique limitations, leading to anesthesia failure. Although numerous studies have examined the cold test and EPT in assessing the success of local anesthesia, no standardized method has been established. This study evaluated the effectiveness of electric pulp test (EPT) and cold tests in assessing the depth of anesthesia in patients with symptomatic irreversible pulpitis (SIP) in the mandibular first molar teeth. MethodsA cross-sectional study was conducted on 50 patients with SIP who met the inclusion criteria and exhibited lip numbness. Following the administration of the IANB and confirmation of lip numbness, cold tests and EPT were performed on all patients. Subsequently, the preparation of the access cavity (gold standard test) was initiated, and patients' responses during cavity preparation were recorded as either "presence of pain or discomfort" or "absence of pain or discomfort," indicating IANB failure and success, respectively. Sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), positive and negative likelihood ratios (LR-/+), and accuracy (AC) with 95% confidence intervals (CI) were calculated for each test separately as well as for sequential testing. ResultsIANB failure was determined in 56% of the patients. A comparative analysis of diagnostic tests (cold test and EPT) showed no significant difference in SN, NPV, and AC; however, the cold test had higher SP, PPV, and LR+. Combining cold test and EPT evaluations improved SN, NPV, PPV, and LR-, but SP and AC were similar to EPT alone. No correlation was found between IANB success and patient age, sex, or initial pain. ConclusionsDespite evidence of lip numbness, a significant number of IANBs failed in cases of painful pulpitis. A positive result from the cold test strongly indicated anesthesia failure. The findings of the current study suggested that when the cold test yielded a negative result, further evaluation with EPT was necessary to confirm anesthetic success and ensure complete pain control.

Cadaver study of ultrasound-guided pudendal nerve block in six horses

Cadaver study of ultrasound-guided pudendal nerve block in six horses

Comparison of two ultrasound-guided versus anatomical landmarks techniques for inferior alveolar nerve block in dogs

Comparison of two ultrasound-guided versus anatomical landmarks techniques for inferior alveolar nerve block in dogs

Development and validation of 3D printed epidural nerve block simulation model in dogs

Development and validation of 3D printed epidural nerve block simulation model in dogs

A Randomized Study of Cryoablation of Intercostal Nerves in Patients Undergoing Minimally Invasive Thoracic Surgery

ObjectivesMinimally invasive thoracic surgery can cause significant pain, and optimizing pain control after surgery is highly desirable. We examined pain control after intercostal nerve block with or without cryo-ablation of the intercostal nerves. MethodsThis was a randomized study (NCT05348447) of adults scheduled for a minimally invasive thoracic procedure. Each intercostal space near the incision site was injected with lidocaine and bupivacaine with epinephrine (standard-of-care). The cryo-analgesia group also had 5-6 intercostal nerves ablated. The primary outcome was the amount of narcotics (in morphine mg equivalent, MME) taken during the postoperative hospital stay and the first two weeks post-discharge. Secondary outcomes were incentive spirometry (IS) volume and pain scores in the hospital and pain and neuropathy scores at two weeks. ResultsOur final cohort contained 103 patients (52 standard-of-care; 51 cryo-analgesia). There were no differences between the treatment groups in MMEs administered during the hospital stay (44.9 mg standard of care vs. 38.4 mg cryo-analgesia), total MME at two weeks (108.8 vs. 95.2 mg), or pain assessed on postoperative day (POD) 1 (3.8 and 3.3), POD2 (2 and 3.5), or two weeks (2 and 3.5). The decrease in IS in the postoperative period was not significantly different between the two groups. Patients in the cryo-analgesia group had higher neuropathy scores (8 vs. 13, p=0.019) two weeks after surgery. ConclusionsIn this randomized study, cryo-analgesia did not decrease postoperative pain or narcotic requirements. Cryo-analgesia increased neuropathic pain two weeks after surgery.