Effect of preemptive use of a nonsteroidal anti-inflammatory drug and a corticosteroid on the efficacy of inferior alveolar nerve blockade and postoperative pain control in endodontic treatment of molars with symptomatic pulpitis: A randomized double-blind placebo-controlled clinical trial

AIM

The anaesthetic success rate of an inferior alveolar nerve block (IANB) in mandibular molars with irreversible symptomatic pulpitis can be low, and postoperative pain control in teeth with this diagnosis can be challenging. This study aimed to evaluate the influence of preemptive use of dexamethasone and oral potassium diclofenac on the success of IANB. The influence of these drugs on the intensity of postoperative pain was assessed as a secondary outcome.

METHODOLOGY

Eighty-four patients with mandibular molars diagnosed with irreversible symptomatic pulpitis recorded preoperative pain intensity using a cold thermal test and a modified Numerical Rating Scale (mNRS). Sixty minutes before the anaesthetic procedure, patients were randomly assigned to one of three groups based on the medication they received: dexamethasone (4 mg), diclofenac potassium (50 mg), or placebo. All patients received IANB with 4% articaine (1:200 000 epinephrine), and 15 min later, they were evaluated for pain intensity using the cold thermal test. Anaesthetic success was analysed. The pain intensity was then recorded, and endodontic treatment and provisional restoration of the tooth were executed in a single session. Patients were monitored for 6, 12, 24, 48 and 72 h using the mNRS to assess the intensity of postoperative pain.

RESULTS

There was a statistically significant increase in anaesthetic success when 4 mg dexamethasone (39.3%) or 50 mg diclofenac potassium (21.4%) was used compared to the placebo group (3.6%) (p < .001), with no significant difference between the two drugs. Regarding postoperative pain, dexamethasone was superior to placebo at 6 h (p < .001), with diclofenac having an intermediate behaviour, not differing between dexamethasone and placebo (p > .05). There was no significant difference amongst the groups at 12 h (p > .05). At 24, 48 and 72 h, the effectiveness of dexamethasone and diclofenac were comparable, and both were superior to placebo (p < .001).

CONCLUSION

The use of dexamethasone or diclofenac potassium was favourable in terms of increasing the success rate of inferior alveolar nerve block in cases of mandibular molars with irreversible symptomatic pulpitis and decreased the occurrence of postoperative pain when compared to the use of a placebo.

Noninferiority trials in acute pain research: a valid approach or a slippery slope?

The conduct and reporting of studies with a noninferiority hypothesis is challenging because of the complexity involved in their design and interpretation. However, studies with a noninferiority design have increased in popularity. A recently published trial reported on the noninferiority of lidocaine infusion to epidural analgesia in major abdominal surgeries. Apart from needing a critical appraisal, this draws attention to improve our understanding of noninferiority study framework and its unique features. Given the increasing focus on using various analgesic adjuncts and multiple approaches to fascial plane blocks to avoid more definitive and standard approaches, it is imperative that particular attention is paid to appropriate execution and reporting of noninferiority studies.

Assessing spontaneous sensory neuron activity using in vivo calcium imaging

ABSTRACT

Heightened spontaneous activity in sensory neurons is often reported in individuals living with chronic pain. It is possible to study this activity in rodents using electrophysiology, but these experiments require great skill and can be prone to bias. Here, we have examined whether in vivo calcium imaging with GCaMP6s can be used as an alternative approach. We show that spontaneously active calcium transients can be visualised in the fourth lumbar dorsal root ganglion (L4 DRG) through in vivo imaging in a mouse model of inflammatory pain. Application of lidocaine to the nerve, between the inflamed site and the DRG, silenced spontaneous firing and revealed the true baseline level of calcium for spontaneously active neurons. We used these data to train a machine learning algorithm to predict when a neuron is spontaneously active. We show that our algorithm is accurate in 2 different models of pain: intraplantar complete Freund adjuvant and antigen-induced arthritis, with accuracies of 90.0% ±1.2 and 85.9% ±2.1, respectively, assessed against visual inspection by an experienced observer. The algorithm can also detect neuronal activity in imaging experiments generated in a different laboratory using a different microscope configuration (accuracy = 94.0% ±2.2). We conclude that in vivo calcium imaging can be used to assess spontaneous activity in sensory neurons and provide a Google Colaboratory Notebook to allow anyone easy access to our novel analysis tool, for the assessment of spontaneous neuronal activity in their own imaging setups.

Analgesia in Transcutaneous Laryngeal Botulinum Toxin Injections: A Randomized Crossover Trial

OBJECTIVES

There is an absence of data in the literature regarding methods to improve the patient experience during the performance of awake in-office laryngeal injections. This study sought to evaluate whether the use of local anesthetic or a vibrating instrument decreased overall pain experienced by patients with laryngeal dystonia, frequently referred to as spasmodic dysphonia (SD), undergoing transcervical botulinum toxin injections.

METHODS

This was an unblinded, prospective randomized control trial with a crossover design where each patient received transcutaneous transcricothyroid injection of botulinum toxin with alternating use of no anesthesia, local anesthesia (2% lidocaine in 1:100,000 epinephrine), and vibrating instrument in three consecutive laryngeal injections to treat adductor SD. Patients were randomized to the order they received these treatments. Patients measured pain on a 0-10 visual analogue scale (VAS) and selected their preferred technique after receiving all three analgesic modalities.

RESULTS

Thirty-two patients completed the study. There was no statistically significant difference in pain between the three analgesic techniques (p = 0.38). The most preferred analgesic technique was the vibrating wand (44% (14/32)). Lidocaine was the second most preferred (37% (12/32)) and 19% (6/32) of patients preferred nothing. When combining the wand and nothing groups, 63% of patients preferred one of these two methods (95% exact CI: 44%-79%).

CONCLUSION

There was no statistically significant difference in median pain experienced by patients during laryngeal botulinum toxin injection between these different analgesic modalities. More than half of the patients selected a preference for a technique that did not include lidocaine. This data supports individualization of analgesia during transcutaneous laryngeal injections.

LEVEL OF EVIDENCE

2 Laryngoscope, 134:2277-2281, 2024.

Lidocaine Spray for Acute Postsurgical Pain Control After Posterior Pharyngeal Flap Surgery

OBJECTIVES

This study evaluated the use of lidocaine spray for acute postsurgical pain control after posterior pharyngeal flap surgery.

METHODS

Fifty patients aged 4 to 14 years who were scheduled to undergo elective posterior pharyngeal flap surgery were randomized to receive 2.4% lidocaine spray (Group L) or an identical volume of placebo spray (Group C) on the surgical field at the end of the surgery. The primary outcome was the maximum postoperative pain score in the postanesthesia care unit.

RESULTS

The maximum pain score in Group L was significantly lower than that in Group C (p = 0.001). The incidence of moderate-to-severe pain in the postanesthesia care unit was significantly lower in Group L than that in Group C (p < 0.001). In the postanesthesia care unit, more patients in Group C were prescribed rescue analgesics (p < 0.001). The time to the first rescue analgesic was also significantly shorter in Group L (p < 0.001). The incidence and maximum score of emergence agitation were lower in Group L than in Group C. Compared with Group C, Group L showed earlier postoperative fluid intake (p = 0.001). Moreover, the score for parental satisfaction with pain control was higher in Group L than in Group C (p < 0.001).

CONCLUSIONS

Our findings indicated that the use of 2.4% lidocaine aerosol spray on the surgical site at the end of the surgery could produce good analgesia for acute postoperative pain, reduce the incidence and severity of EA, and shorten the time to restore fluid intake.

LEVEL OF EVIDENCE

2 Laryngoscope, 134:2438-2443, 2024.

Is epidural analgesia non-inferior to intrathecal fentanyl as initiation for neuraxial analgesia in early non-spontaneous labour?

BACKGROUND AND AIM

Intrathecal fentanyl, using the combined spinal-epidural (CSE) technique, provides rapid analgesia during early labour. Because of the technique's more complex and invasive nature, as its replacement we assessed the use of epidural analgesia in primiparous parturients with induced labour. The study was registered at www.

CLINICALTRIALS

gov (NCT04645823). The aim was to compare the efficacy, duration of analgesia and maternal satisfaction. The primary outcome was the difference in pain visual analogue scale (VAS) between the interventions at 20 min after the analgesia administration.

METHODS

Sixty volunteering parturients were randomly allocated in 1:1 ratio to receive either intrathecal fentanyl 20 μg or epidural analgesia (fentanyl 100 μg and lidocaine 80 mg). Contraction pain and maternal satisfaction were assessed by 0-100 mm VAS for 30 min, respectively. Foetal heart rate abnormalities, the time to first epidural dose and the incidence of pruritus were recorded. Non-inferiority margin for mean (95% CI) VAS after epidural analgesia was set at 20 mm above the VAS value for intrathecal fentanyl at 20 min.

RESULTS

The contraction pain VAS fell from (median [interquartile range, IQR]) 82 (14) to 13 (20) mm and 76 (17) to 12 (27) mm in 20 min following the intrathecal fentanyl and epidural analgesia, respectively. The absolute mean difference (epidural-intrathecal fentanyl) in the VAS values was 3.3(-0.06 to 6.66) mm indicating non-inferiority. The median time to reach VAS <30 mm was 10 min in both groups. The duration until request for supplemental analgesia was 82(69-95) and 91(75-106) min after intrathecal fentanyl and epidural analgesia, respectively. The difference for the duration (epidural-intrathecal fentanyl) was 9 (6-12) min and for satisfaction-VAS 0.3 (-3.0 to 3.7) mm. There were no differences between the groups in the incidence of foetal heart rate abnormalities, while pruritus was more common after intrathecal fentanyl.

CONCLUSION

After 20 min, epidural analgesia by lidocaine and fentanyl was within the non-inferior threshold compared with intrathecal fentanyl in efficacy. The duration of action was not shorter than that of intrathecal fentanyl and maternal satisfaction was also similar.

Pain management after open colorectal surgery: An update of the systematic review and procedure-specific postoperative pain management (PROSPECT) recommendations

BACKGROUND

Open colectomy is still performed around the world and associated with significant postoperative pain.

OBJECTIVES

Unpublished recommendations based on a systematic review were proposed by the PROcedure SPECific postoperative pain managemenT (PROSPECT) group in 2016. We aimed to update these recommendations by evaluating the available literature and develop recommendations for optimal pain management after open colectomy according to the PROSPECT methodology.

DESIGN AND DATA SOURCES

A systematic review using the PROSPECT methodology was undertaken. Randomised controlled trials and systematic reviews published in the English language from 2016 to 2022 assessing postoperative pain after open colectomy using analgesic, anaesthetic or surgical interventions were identified. The primary outcome included postoperative pain scores.

RESULTS

The previous 2016 review included data from 93 studies. Out of 842 additional eligible studies identified, 13 new studies were finally retrieved for analysis. Intra-operative and postoperative interventions that improved postoperative pain were paracetamol, epidural analgesia. When epidural is not feasible, intravenous lidocaine or bilateral TAP block or postoperative continuous pre-peritoneal infusion are recommended. Intra-operative and postoperative Cyclo-oxygenase (COX)-2 specific-inhibitors or non-steroidal anti-inflammatory drugs (NSAIDs) are recommended for colonic surgery.

CONCLUSIONS

The analgesic regimen for open colectomy should include intra-operative paracetamol and COX-2 specific inhibitors or NSAIDs (restricted to colonic surgery), epidural and continued postoperatively with opioids used as rescue analgesics. If epidural is not feasible, bilateral TAP block or IV lidocaine are recommended. Safety issues should be highlighted: local anaesthetics should not be administered by two different routes at the same time. Because of the risk of toxicity, careful dosing and monitoring are necessary.

Using part of the initial analgesic dose as the epidural test dose did not delay the onset of labor analgesia: a randomized controlled clinical trial

BACKGROUND

Epidural test dose for labor analgesia is controversial and varies widely in clinical practice. It is currently unclear whether using a portion of the initial dose for analgesia as the test dose delays the onset time of analgesia, compared to the traditional test dose.

METHODS

One hundred and twenty-six parturients who chose epidural analgesia during labor were randomly assigned to two groups. The first dose in group L was 3 ml 1.5% lidocaine, and in the RF group was 10 ml 0.1% ropivacaine combined with 2 μg/ml fentanyl. After 3 min of observation, both groups received 8 ml 0.1% ropivacaine combined with 2 μg/ml fentanyl. The onset time of analgesia, motor and sensory blockade level, numerical pain rating scale, patient satisfaction score, and side effects were recorded.

RESULTS

The onset time of analgesia in group RF was similar to that in group L (group RF vs group L, 7.0 [5.0-9.0] minutes vs 8.0 [5.0-11.0] minutes, p = 0.197). The incidence of foot numbness (group RF vs group L, 34.9% vs 57.1%, p = 0.020) and foot warming (group RF vs group L, 15.9% vs 47.6%, p < 0.001) in group RF was significantly lower than that in group L. There was no difference between the two groups on other outcomes.

CONCLUSIONS

Compared with 1.5% lidocaine 3 ml, 0.1% ropivacaine 10 ml combined with 2 μg/ml fentanyl as an epidural test dose did not delay the onset of labor analgesia, and the side effects were slightly reduced.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn (ChiCTR2100043071).

Unlocking tracheoesophageal speech from pharyngoesophageal spasm: preliminary results of a videofluoroscopic-guided botulinum toxin A injection technique

PURPOSE

The tracheoesophageal puncture for the voice prosthesis (VP) placement is the recognized gold standard in post-laryngectomy voice rehabilitation. Despite the development of specific intraoperative techniques, a subset of patients will suffer from poor functional outcomes due to pharyngoesophageal spasms (PES). This paper evaluates the functional outcomes after transcutaneous botulinum toxin type A (BTX-A) infiltration for PES with a videofluoroscopy-guided technique.

METHODS

Since 2022, eight consecutive patients with VP and affected by PES were treated with BTX-A injection by a standard videofluoroscopic guided technique at the European Institute of Oncology, IRCCS (IEO) in Milan. A lidocaine test was performed pre-operatively to evaluate the potential effect of chemical neurectomy. All patients with positive lidocaine tests were injected with 50 IU of BTX-A (Allergan, Irvine, CA) according to the sites marked during the videofluoroscopy. Reported symptoms (VHI, SECEL), perceptual (INFVo), aerodynamic (MPT) and manometric parameters were collected before and after treatment.

RESULTS

In all cases, BTX-A was performed as an outpatient procedure without complications. For seven patients, only one BTX-A injection was needed, while one patient required a re-injection. Subjective and perceptive improvement after BTX-A was significant for VHI, SECEL and INFVo. MPT showed significant improvement after a chemical neurectomy. After a mean follow-up of 6 months, all patients maintained a good TES quality.

CONCLUSION

The videofluoroscopic guided BTX-A injection of the pharyngoesophageal tract showed to be a feasible and reproducible technique in all cases. The pharyngoesophageal videofluoroscopy allows defining of patients' anatomical landmarks that help the surgeon to perform a homogeneous injection, empowered by post-injection massage.

Postoperative Pain Management in Coronary Artery Bypass Grafting: An Integrative Review

PURPOSE

To identify pharmacological and nonpharmacological interventions adopted for pain relief in the postoperative period of coronary artery bypass graft surgery.

DESIGN

Integrative review.

METHODS

Studies published in English, Spanish, and Portuguese from January 2010 to December 2019 in Cumulative Index to Nursing and Allied Health Literature (CINAHL), Latin American and Caribbean Literature on Health Science, PubMed, and Web of Science. Two hundred studies were identified and eleven were included. Methodological analysis was performed using the Medical Education Research Study Quality Instrument.

FINDINGS

The studies found were organized into three thematic categories: pharmacological interventions (methadone, morphine, lidocaine gel, remifentanil, sufentanil, and nefopam), nonpharmacological interventions (low-level laser therapy, light-emitting diode, Class IV laser, and transcutaneous nerve stimulation) and anesthetic techniques (dexmedetomidine, ultrasound-guided pectoral nerve block, high thoracic epidural analgesia, and perioperative parasternal block with levobupivacaine).

CONCLUSIONS

A greater tendency to use drug strategies for postoperative pain relief was identified. The drugs used demonstrated efficacy and safety in the treatment of pain, with the exception of nefopam, which showed little benefit in this population. Nonpharmacological interventions, used as adjuvants to drug treatment, were shown to be safe, effective, and well tolerated by the patients.

Topical anaesthesia and decongestion in rhinology

Topical anaesthesia and decongestion of the sinonasal mucosa are used commonly in rhinology practice to facilitate nasal endoscopy, as well as debridement and biopsies. Topical agents used for sinonasal anaesthesia include lignocaine, tetracaine and cocaine. Unlike lignocaine and tetracaine, cocaine also has a decongestant effect. Phenylephrine, oxymetazoline, xylometazoline or adrenaline are usually added to lignocaine and tetracaine to provide decongestion. Several studies have been performed seeking to identify the optimal nasal preparation for nasal endoscopy in the clinic setting. However, there remains no clear consensus in the literature resulting in ongoing wide variation between anaesthetic-decongestant preparations used in clinical practice. Indeed, some authors have argued that no anaesthetic is required at all for flexible nasendoscopy despite the apparent consensus that nasal instrumentation is generally uncomfortable, inferred by the persistence of ongoing research in this area. This review provides a practical summary of local anaesthetic and decongestant pharmacology as it relates to rhinologic practice and summarises the literature to date, with the goal of identifying current gaps in the literature and guiding future research efforts.

Cervical Epidural Anesthesia Combined with Sedation for Neck Cancer Surgery: A Case Report

Cervical epidural anesthesia (CEA) is a well-established technique and is suitable for various surgeries, including carotid, thyroid, airway, neck cancer, breast, and upper limb procedures. We report the case of an elderly woman with a recurrent neck mass secondary to metastatic papillary thyroid carcinoma causing neurovascular compression, who underwent surgery under CEA. Five milliliters of 0.5% bupivacaine and 5 mL of 2% lidocaine (total 10 mL) were administered into the cervical epidural space. Combined with sedation, CEA in our case provided optimal anesthetic conditions, maintaining spontaneous ventilation, preventing airway collapse, ensuring patient comfort, and facilitating surgery.

Intraoperative pharmacologic opioid minimisation strategies and patient-centred outcomes after surgery: a scoping review

BACKGROUND

Postoperative patient-centred outcome measures are essential to capture the patient's experience after surgery. Although a large number of pharmacologic opioid minimisation strategies (i.e. opioid alternatives) are used for patients undergoing surgery, it remains unclear which strategies are most promising in terms of patient-centred outcome improvements. This scoping review had two main objectives: (1) to map and describe evidence from clinical trials assessing the patient-centred effectiveness of pharmacologic intraoperative opioid minimisation strategies in adult surgical patients, and (2) to identify promising pharmacologic opioid minimisation strategies.

METHODS

We searched MEDLINE, Embase, CENTRAL, Web of Science, and CINAHL databases from inception to February 2023. We included trials investigating the use of opioid minimisation strategies in adult surgical patients and reporting at least one patient-centred outcome. Study screening and data extraction were conducted independently by at least two reviewers.

RESULTS

Of 24,842 citations screened for eligibility, 2803 trials assessed the effectiveness of intraoperative opioid minimisation strategies. Of these, 457 trials (67,060 participants) met eligibility criteria, reporting at least one patient-centred outcome. In the 107 trials that included a patient-centred primary outcome, patient wellbeing was the most frequently used domain (55 trials). Based on aggregate findings, dexmedetomidine, systemic lidocaine, and COX-2 inhibitors were promising strategies, while paracetamol, ketamine, and gabapentinoids were less promising. Almost half of the trials (253 trials) did not report a protocol or registration number.

CONCLUSIONS

Researchers should prioritise and include patient-centred outcomes in the assessment of opioid minimisation strategy effectiveness. We identified three potentially promising pharmacologic intraoperative opioid minimisation strategies that should be further assessed through systematic reviews and multicentre trials. Findings from our scoping review may be influenced by selective outcome reporting bias.

STUDY REGISTRATION

OSF - https://osf.io/7kea3.

Efficacy of the TuttleNumbNow Intraosseous Method for Pulpal Anesthesia in the Mandibular First Molar: A Prospective, Randomized, Crossover Study

INTRODUCTION

Previous studies on intraosseous (IO) anesthesia as a primary injection have shown high success rates. The TuttleNumbNow (TNN; Orem, UT) is a new primary IO injection technique that has not been scientifically evaluated. Therefore, the purpose of this prospective randomized, crossover study was to evaluate the anesthetic efficacy of the TNN IO technique using the Septoject Evolution needle (Septodont, Saint-Maur-des-Fosses, France) compared with buccal infiltration for pulpal anesthesia in mandibular first molars.

METHODS

One hundred four healthy subjects were randomly assigned to 2 treatment groups separated by at least 2 weeks. One set of injections consisted of buccal infiltration of the mandibular first molar using 1.8 mL 4% articaine with 1:100,000 epinephrine followed by a mock TNN injection distal to the mandibular first molar. The other set of injections was a mock buccal infiltration of the mandibular first molar followed by a TNN injection of 1.8 mL 4% articaine with 1:100,000 epinephrine distal to the mandibular first molar. Statistical analyses were performed.

RESULTS

For the mandibular first molar, which had a 42% anesthetic success rate (highest 80 reading) with buccal infiltration compared with 49% with the TNN, no statistically significant difference in success was observed (P = .2115).

CONCLUSIONS

The TNN technique has been advocated as an IO injection. However, the inability to deliver anesthetic solution to the cancellous bone resulted in an anesthetic success rate of 49%. The success was statistically similar to a buccal infiltration (42%) and would not provide adequate pulpal anesthesia as a primary injection.

Comparative Evaluation of the Local Anesthetic Action of Tramadol Hydrochloride With Adrenaline Versus Lidocaine Hydrochloride With Adrenaline for Maxillary Exodontia: A Randomized Control Trial

BACKGROUND

Tramadol hydrochloride (T-HCl) has demonstrated to have a local anesthetic effect similar to lidocaine hydrochloride (L-HCl) when administered locally for minor oral surgical procedures.

PURPOSE

Our study aimed to compare the anesthetic effect of T-HCl versus L-HCl in maxillary premolar extraction.

STUDY DESIGN, SETTING AND SAMPLE

The study is a split-mouth, double-blind randomized clinical trial at the Faculty of Dental Sciences, Ramaiah University of Applied Sciences, Bengaluru, India. The study sample was composed of patients referred for maxillary bicuspid extraction. Patients were excluded from the sample if, allergic to the study drugs, pregnant or lactating females, and smokers.

EXPOSURE VARIABLE

The variable is an anesthetic drug administered for local anesthesia and it is grouped into 2 categories, T-HCl and L-HCl. A supraperiosteal infiltration of T-HCl with adrenaline on one side and L-HCl with adrenaline on the contralateral side was injected.

MAIN OUTCOME VARIABLE

The primary outcome variable was profound anesthesia of T-HCl, where the patient sensed the loss of sensation of touch, temperature, and pain. Secondary outcomes were onset and duration of anesthesia, intraoperative pain, postoperative analgesia, and adverse reactions, were recorded.

ANALYSES

Inferential statistics, the χ2 Test, the Mann-Whitney Test, and the Wilcoxon signed-rank test were used to compare the parameters. The level of significance was set at ≤ 0.05.

RESULTS

A total of 40 patients were included, and 80 teeth were extracted. Profound anesthesia was achieved in all the cases. The mean subjective duration of anesthesia in the T-HCl and L-HCl groups was 130.80 ± 20.01 minutes and 111.40 ± 14.87 minutes, respectively, with a P value of .001. The mean Visual Analogue Scale (VAS) score for pain during the procedure in the T-HCl and L-HCl groups was 0.60 ± 0.67 and 1.10 ± 0.71, respectively, with a P value of .002. The mean Visual Analogue Scale score for pain postoperatively in the T-HCl and L-HCl groups was 0.70 ± 0.72 and 1.40 ± 0.67, respectively, with a P value of .001. Six patients in T-HCl required postoperative analgesia when compared to 18 patients in L-HCl (P value < .003).

CONCLUSIONS AND RELEVANCE

T-HCl provides similar anesthetic outcomes in the extraction of maxillary bicuspids as L-HCl.

Drug-induced aseptic meningitis after an interlaminar lumbar epidural steroid injection

BACKGROUND

This case report describes a rare instance of drug-induced aseptic meningitis after an interlaminar lumbar epidural steroid injection.

CASE PRESENTATION

A 74 year-old female patient presented to the ED post-procedure day three after an L4-L5 interlaminar lumbar epidural steroid injection with fever, nausea, and vomiting. The patient had previously undergone numerous lumbar epidurals without complications and used identical medications, which included 1% lidocaine, iohexol contrast, methylprednisolone (Depo-medrol), and normal saline. Pertinent labs included a WBC of 15,000 cells/μL. Lumbar MRI revealed L4-S1 aseptic arachnoiditis. Two bone scans with Gallium and T-99 confirmed no infectious process. The patient then had a second admission months later with similar presenting symptoms and hospital course after repeating the lumbar epidural steroid injection. Lumbar MRI and CSF studies confirmed aseptic meningitis.

CONCLUSION

This patient's repeated admissions from aseptic meningitis were likely caused by irritation of the meningeal layers from a medication used during the procedure.

The value of local dexmedetomidine as an adjuvant to ultrasound-guided wide awake local anesthesia no tourniquet (WALANT) in flexor tendon repair surgeries: a randomized controlled trial

BACKGROUND

The Wide-Awake Local Anesthesia No Tourniquet (WALANT) technique allows intraoperative motor assessment of tendon repair integrity of the hand compared with general anesthesia or brachial plexus block. No studies have tested the effect of adding dexmedetomidine to lidocaine on the analgesic properties of the WALANT technique, which is the aim of our study.

METHODS

A total of 128 patients aged more than 18 years were scheduled for surgical flexor tendon injury repair using WALANT technique. Patients were divided into two equal groups. Ultrasound-guided subcutaneous injection of lidocaine 1% with dexmedetomidine (1 µg/kg), Group D, or without dexmedetomidine, Group C, was performed at four points: proximal to the wrist joint, the distal forearm, palm region, and proximal phalanges. The primary outcome was total morphine consumption throughout the first postoperative day. Secondary outcomes included number of patients requiring rescue analgesia, time to first analgesic request, and pain score.

RESULTS

Total morphine consumption was significantly (P < 0.001) lower in group D (2.66 ± 0.998) than in group C (3.66 ± 1.144) mg. Number of patients requiring rescue analgesia was significantly (P < 0.001) lower in group D (54.7% (35)) than group C (100.0% (64)). The time for first request for analgesia was significantly (P < 0.001) longer in group D (11.31 ± 6.944) than in group C (5.91 ± 4.839) h. Pain score was significantly higher in group C than D at three (P < 0.001), and six (P = 0.001) hours (P = 0.001) postoperatively.

CONCLUSION

Dexmedetomidine significantly improves the analgesic quality of WALANT when added to lidocaine with less opioid consumption.

TRIAL REGISTRATION

(ID: PACTR202203906027106; Date: 31/07/2023).

Efficacy of articaine anesthesia with needle-free/Comfort-in method and conventional needle injection in dental patients with irreversible pulpitis: a randomized clinical trial

OBJECTIVE

To assess the anesthetic efficacy of articaine with the needle-free/Comfort-in™ method compared to the conventional needle method. To assess pain during anesthesia application, onset of anesthesia and patient`s self-reported quality of life-related to oral health after the dental emergency appointment.

MATERIALS AND METHODS

This parallel, randomized clinical trial was conducted by a single operator/dentist in the state of Maranhao, northeast of Brazil. Included participants were adult dental patients with one molar (maxillary) or premolar (maxillary or mandibular) tooth diagnosed with symptomatic irreversible pulpitis. The primary outcome was the anesthetic efficacy, measured using a combination of electrical and cold pulp tests (cold + EPT) and the Numerical Rating Scale (NRS). Secondary outcomes were pain during anesthesia application, onset of anesthesia, and patient`s quality-of-life (measured with the OHIP-14).

RESULTS

62 patients were randomized in the anesthesia needle-free group and Comfort-in group (34.26 ± 10.786 × 33.29 ± 8.399 years old, respectively). The group of patients in the Comfort-in group had 71.0% success. Patients from the Comfort-in group reported statistically lower pain during the anesthesia application than patients from the conventional group (2.13 ± 2.172 × 6.03 ± 3.146 NRS scores, respectively) as well as immediately after the anesthetic procedure. Patients self-reported negative impact in quality of life was similar between groups before (p > 0.05) and after (p > 0.05) the dental emergency.

CONCLUSIONS

Comfort-in™ had similar efficacy to the conventional needle method.

CLINICAL RELEVANCE

This trial showed that it is possible to anesthetize patients with tooth pulpits without using needles to provide comfort mainly to anxious patients.

[Development of an analytical system for dried blood spots for forensic toxicology: a case study of five common drugs and poisons]

Dried blood spot (DBS) technology is a simple and convenient method for collecting, transporting, and storing blood samples on filter paper, and has numerous applications in the clinical, research, and public health settings. This technique is gaining popularity in the field of forensic science because it facilitates the rapid analysis of prohibited drugs in blood samples and offers significant advantages in toxicology scenarios such as drinking-driving screening, drug abuse detection, and doping detection. However, the lack of a standardized system and the fact that its stability and reliability have not been thoroughly researched and demonstrated limit its application in judicial practice in China. DBS samples can be prepared, stored, and analyzed in various ways, all of which may significantly affect the results. In this study, we developed a method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) that focuses on the preparation, pretreatment, analysis, and storage of DBS samples. A thorough investigation was conducted to examine the optimal preparation conditions, including the blood spot matrix, drying technique, and preprocessing parameters, such as the solvent and extraction method. Moreover, the analytical conditions, such as the mobile phase system and elution gradient, were established to facilitate the quantitative detection of methamphetamine, lidocaine, ketamine, fentanyl, and diazepam in both DBS and whole-blood samples. The impact of storage conditions, such as the temperature, humidity, and sealing, on the analytical results of the DBS and whole-blood samples was also examined. The results showed a strong linear relationship for lidocaine and fentanyl within the range of 0.5-100 ng/mL. Similarly, methamphetamine, ketamine, and diazepam exhibited good linearity within the range of 2-100 ng/mL. The coefficients of determination (r2) ranged from 0.9983 to 0.9997, and the limits of detection ranged from 0.2 to 0.5 ng/mL, indicating a high degree of correlation and sensitivity. Stability tests demonstrated that the five target substances remained stable in the DBS for 60 days, with the measured contents deviating from the nominal values by 15%. Moreover, the measurement results of the DBS samples were highly similar to those of the whole-blood samples, with mean percentage differences of 4.44%, 3.50%, 7.66%, 5.10%, and 5.25% for fentanyl, diazepam, ketamine, lidocaine, and methamphetamine, respectively. Throughout the 60-day storage period, the maintenance of temperatures of -20 and 4 ℃, as well as sealing and dry storage, was not necessary. Room temperature was the most practical storage environment for the DBS samples. The results for each target showed very small concentration differences between the whole-blood and DBS samples, indicating that the DBS samples were suitable for drug and poison analysis in blood. Furthermore, the DBSs exhibited high quantitative consistency with the whole-blood samples, rendering them suitable matrices for preserving blood samples. Because DBS samples are easy to handle and store, they can realize the lightweight preservation of blood samples and provide a novel solution for the analysis and preservation of blood samples in public security practice. We recommend conducting comprehensive validations before utilizing DBS for analysis, particularly in terms of quantification, to ensure the judicial reliability of the results.

Retinal artery occlusion after ophthalmic surgery under regional anaesthesia: A narrative review

Two recent cases of central retinal artery occlusion under otherwise uncomplicated sub-Tenon's block that resulted in significant visual loss after cataract surgery prompted us to undertake a literature review of such cases. We identified 97 cases of retinal artery occlusion after ophthalmic surgery under regional anaesthesia that had no immediate signs of block-related complications. These occurred after various intraocular (87%) and extraocular (13%) operations, across a wide range of ages (19-89 years) on patients with (59%) or without (39%) known risk factors. The anaesthetic techniques included 40 retrobulbar blocks, 36 peribulbar blocks, 19 sub-Tenon's blocks, one topical anaesthetic and one unspecified local anaesthetic. Different strengths of lidocaine, bupivacaine, mepivacaine and ropivacaine, either alone or in various combinations, were used. The details of the anaesthetic techniques were often incomplete in the reports, which made comparison and analysis difficult. Only nine cases had their cause (optic nerve sheath injury) identified, while the mechanism of injury was unclear in the remaining patients. Various mechanisms were postulated; however, the cause was likely to be multifactorial due to patient, surgical and anaesthetic risk factors, especially in those with compromised retinal circulation. As there were no definite risk factors identified, no specific recommendations could be made to avoid this devastating outcome. We have provided rationales for some general considerations, which may reduce this risk, and propose anaesthetic options for ophthalmic surgery on the fellow eye if required, based both on our literature review and our personal experience.

Pain experience in patients undergoing topical anesthesia alone versus topical plus intracameral anesthesia during cataract surgery

PURPOSE

To evaluate and compare the pain experience and discomfort during cataract surgery and over the 24 hours after surgery in patients undergoing either topical anesthesia alone or topical anesthesia plus intracameral anesthesia, provided by using a standard topical anesthesia regimen and a 0.2-mL dose of Mydrane®.

METHODS

Prospective study involving 100 patients who underwent cataract surgery receiving either topical anesthesia alone (group 1, n = 50) or topical anesthesia plus intracameral anesthesia (group 2, n = 50) between January 2021 and March 2022. The pain experienced by patients during and after surgery was assessed using a pain scale and a questionnaire. One hour after surgery, patients were asked to rate the intensity of discomfort they experienced throughout the procedure by pointing to a 0-100 Visual Analogue Scale (VAS).

RESULTS

According to VAS measurements, patients who underwent surgery under topical anesthesia reported more significant pain than those who underwent surgery under topical anesthesia plus intracameral anesthesia during and over the 24 hours after surgery. (p = 0.02 and p = 0.01, respectively). Patients undergoing topical anesthesia had 2.34-fold greater odds of having pain during surgery [95% Confidence Interval (CI): 1.58-5.25, p = 0.03].

CONCLUSIONS

Topical anesthesia plus intracameral anesthesia lower intraoperative and postoperative pain levels, improving patient cooperation and representing a useful analgesic delivery method in cataract surgery.

The Beneficial Role of Endotracheal Lidocaine in Mitigating Hemodynamic Responses During Elective Surgical Tracheostomy in Head and Neck Cancer Patients

BACKGROUND

The effectiveness of endotracheal lidocaine administration to reduce sympathetic stimulus after tracheostomy is still uncertain.

PURPOSE

This study aimed to compare the hemodynamic responses of patients undergoing tracheostomy with and without pre-tracheostomy administration of endotracheal lidocaine.

STUDY DESIGN, SETTING AND SAMPLE

A prospective cohort study was conducted at a tertiary care cancer center in the United Kingdom. Patients who underwent tracheostomy as part of their head and neck cancer surgery were included. Exclusion criteria comprised tracheostomies involving special requirements and subjects with documented cardiac history or taking specific medications.

PREDICTOR VARIABLE

The predictor variable was pre-tracheostomy anesthetic management defined as the administration of endotracheal 4 ml 4% lidocaine before tracheostomy coded as lidocaine used or not used.

OUTCOME VARIABLE

The primary outcome measures in this study were the observed hemodynamic responses after tracheostomy, including heart rate, systolic blood pressure, and diastolic blood pressure. The secondary outcome measure in the two groups was the time it took for subjects to return to their pre-tracheostomy baseline hemodynamic parameters, measured in minutes.

ANALYSES

Data analyses included χ2, t-test, analysis of variance, and multivariable regression models. P values < .05 were considered statistically significant.

COVARIATES

The patients' age, sex, body mass index, smoking status, tracheostomy tube size, and tumor stage were evaluated.

RESULTS

The sample included 50 consecutive patients, the majority of whom were male (55%) with a mean age of 62 years (standard deviation[SD] 12) and a mean body mass index of 28 (SD 4). Most patients had stage III or IV oral cancers (59%). Following surgical tracheostomy, the group that received endotracheal lidocaine demonstrated significantly less hemodynamic variability when compared with the control group. The case group exhibiting lower systolic blood pressure (117 [SD 10] vs 136 [SD 18]), diastolic blood pressure (62 [SD 4] vs 68 [SD 4]), and heart rate (72 [SD 4] vs 78 [SD 4]), with statistical significance (P < .05). However, there was no significant difference in the time taken for the two groups to return to their pre-tracheostomy baseline hemodynamic parameters.

CONCLUSIONS AND RELEVANCE

This study demonstrates an association between the preadministration of 4% endotracheal lidocaine with an observed attenuation in hemodynamic response following surgical tracheostomy in head and neck cancer patients.

Applying Topical Anesthetic on Pediatric Lacerations in the Emergency Department: A Quality Improvement Project

OBJECTIVES

Caring for pediatric lacerations in the emergency department (ED) is typically painful because of irrigation and suturing. To improve this painful experience, we aimed to increase the use of a topical anesthetic, Eutectic Mixture of Local Anesthetics (EMLA) on eligible pediatric lacerations with an attainable, sustainable, and measurable goal of 60%. The baseline rate of applying topical anesthetic to eligible lacerations was 23% in our ED. We aimed to increase the use of topical anesthetics on eligible pediatric lacerations to a measurable goal of 60% within 3 months of implementing our intervention.

METHODS

We conducted a prospective, single-center, interrupted time series, ED quality improvement project from November 2019 to July 2020. A multidisciplinary team of physicians and nurses performed a cause-and-effect analysis identifying 2 key drivers: early placement of EMLA and physician buy-in on which we built our Plan, Do, Study, and Act (PDSA) cycles. We collected data on number of eligible patients receiving EMLA, as well as patient and physician feedback via phone calls within 2 days after encounter. Balancing measures included ED length of stay (LOS), patient and physician satisfaction with EMLA, and adverse effects of EMLA.

RESULTS

We needed 3 PDSA cycles to reach our goal of 60% in 3 months, which was also maintained for 5 months. The PDSA cycles used educational interventions, direct provider feedback about noncompliance, and patient satisfaction results obtained via phone calls. Balancing measures were minimally impacted: 75% good patient satisfaction, no adverse events but an increase in LOS of patients who received EMLA compared with those who did not (1.79 ± 0.66 vs 1.41 ± 0.83 hours, P < 0.001). The main reasons for dissatisfaction for physicians were the increased LOS and the preference for procedural sedation or intranasal medications.

CONCLUSIONS

With a few simple interventions, our aim of applying EMLA to 60% of eligible pediatric lacerations was attained and maintained.

Chloroprocaine 3% Gel as a Novel Ocular Topical Anesthetic: Results from a Multicenter, Randomized Clinical Trial in Patients Undergoing Cataract Surgery

Purpose: To compare the efficacy and safety of a novel ophthalmic anesthetic, chloroprocaine 3% gel to tetracaine 0.5% eye drops in patients undergoing cataract surgery with phacoemulsification. Methods: This was a prospective, randomized, multicenter, active-controlled, masked-observer, parallel group competitive equivalence study. The study comprised 338 patients having routine cataract extraction by clear corneal phacoemulsification, randomized to receive 3 drops of chloroprocaine gel (n = 166) or tetracaine eye drops (n = 172) before surgery. The primary objective of the study was to assess the equivalence of chloroprocaine gel to tetracaine eye drops as proportion of patients with successful ocular surface anesthesia, without any supplementation just before intraocular lens implantation. Safety measurements were pain, irritation, burning, stinging, photophobia, and foreign body sensation, graded by the patient and objective ocular signs. Results: Equivalence was demonstrated, with a somewhat higher success rate of chloroprocaine gel: 152/166 (92.0%) chloroprocaine versus 153/172 (90.5%) tetracaine patients achieved ocular surface anesthesia with no supplementation. Difference in proportions was 1.5% confidence interval [95% CI: (-3.6 to 6.6)] and 90% CI fell within (-10 to 10). Mean onset of anesthesia was 1.35 ± 0.87 min for chloroprocaine and 1.57 ± 1.85 for tetracaine (P = 0.083). Mean duration of anesthesia was 21.57 ± 12.26 min for chloroprocaine and 22.04 ± 12.58 for tetracaine (P = 0.574). No treatment emergent adverse events related to chloroprocaine were reported and no relevant findings related to local tolerance or vital signs were observed in both arms. Conclusions: Results obtained from the present cataract study demonstrated that chloroprocaine 3% ophthalmic gel is safe and effective, representing a valid alternative in ocular topical anesthesia. Clinical Trial Registration number: NCT04685538.

Analysis of the effectiveness of PDT with 5-aminolevulinic acid in comparison to blue/red light combined with intralesional triamcinolone injection in treatment of severe inflammatory acne: A retrospective study

OBJECTIVE

In this study, the therapeutic effect of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in comparison to blue/red light combined with intralesional triamcinolone injection for severe inflammatory acne was evaluated and analyzed.

METHODS

One hundred and four cases of severe inflammatory acne were analyzed in this study. They were divided into two groups as control and observation groups, 52 cases in each group. The control group (group A) received red and blue light combined with triamcinolone injection and lidocaine injection (1:4), while the observation group (Group B) was treated with ALA-PDT. Finally, the therapeutic effect and the occurrence of adverse reactions were compared between the two groups.

RESULTS

After 2, 4 and 6 weeks, the effectiveness rates of group B was 28.85%, 75.00%, and 86.54%, respectively while it was 9.62%, 51.92%, and 69.23%, respectively in group A. The difference between A and B was statistically remarkable (χ2 = 6.1905, 5.9713, 4.5217, p = 0.0128, 0.0145, 0.0335 at p < 0.05). In addition, the incidence of adverse reactions in B was 5.77%, lower than A (32.69%). This difference between A and B was statistically remarkable (χ2  = 12.1333, p = 0.0005). After 2, 4, and 6 weeks of treatment, the number of residual lesions in the group B group was remarkably lower than group A (p < 0.01). There was remarkable difference in the incidence of pain, burning sensation, pigmentation and erythema between the two groups.

CONCLUSIONS

The therapeutic effect of ALA-PDT in the treatment of severe acne is better than red blue light combined with triamcinolone injection and lidocaine injection. In addition, ALA-PDT has an ideal effect in the treatment of severe acne.

Multicenter, Randomized, Placebo-controlled Crossover Trial Evaluating Topical Lidocaine for Mechanical Cervical Pain

BACKGROUND

There are few efficacious treatments for mechanical neck pain, with controlled trials suggesting efficacy for muscle relaxants and topical nonsteroidal anti-inflammatory drugs. Although studies evaluating topical lidocaine for back pain have been disappointing, the more superficial location of the cervical musculature suggests a possible role for topical local anesthetics.

METHODS

This study was a randomized, double-blind, placebo-controlled crossover trial performed at four U.S. military, Veterans Administration, academic, and private practice sites, in which 76 patients were randomized to receive either placebo followed by lidocaine patch for 4-week intervals (group 1) or a lidocaine-then-placebo patch sequence. The primary outcome measure was mean reduction in average neck pain, with a positive categorical outcome designated as a reduction of at least 2 points in average neck pain coupled with at least a 5-point score of 7 points on the Patient Global Impression of Change scale at the 4-week endpoint.

RESULTS

For the primary outcome, the median reduction in average neck pain score was -1.0 (interquartile range, -2.0, 0.0) for the lidocaine phase versus -0.5 (interquartile range, -2.0, 0.0) for placebo treatment (P = 0.17). During lidocaine treatment, 27.7% of patients experienced a positive outcome versus 14.9% during the placebo phase (P = 0.073). There were no significant differences between treatments for secondary outcomes, although a carryover effect on pain pressure threshold was observed for the lidocaine phase (P = 0.015). A total of 27.5% of patients in the lidocaine group and 20.5% in the placebo group experienced minor reactions, the most common of which was pruritis (P = 0.36).

CONCLUSIONS

The differences favoring lidocaine were small and nonsignificant, but the trend toward superiority of lidocaine suggests more aggressive phenotyping and applying formulations with greater penetrance may provide clinically meaningful benefit.

EDITOR’S PERSPECTIVE

Molecular interactions of hydrated co-amorphous systems of prilocaine and lidocaine

It is generally accepted that water as a plasticizer can decrease the glass transition temperatures (Tgs) of amorphous drugs and drug excipient systems. However, previous studies suggest that water, as an anti-plasticizer, can increase the Tgs of co-amorphous systems of prilocaine (PRL) and lidocaine (LID). In order to investigate the intermolecular interactions between water and co-amorphous PRL-LID systems, Fourier transform infrared spectroscopy (FTIR) and principal component analysis (PCA) were conducted. Water was found to bind with the carbonyl groups of PRL and LID molecularly evenly in the hydrated co-amorphous PRL-LID systems. Quantum chemical simulations visually confirmed the interactions between water and co-amorphous PRL-LID systems. Furthermore, the physical stability of hydrated co-amorphous PRL-LID systems was improved due to the anti-plasticizing effect of water, compared with the anhydrous samples. The preference of water to interact with the carbonyl groups of PRL and LID as binding sites could be associated with the anti-plasticizing effect of water on the co-amorphous PRL-LID systems.

Local anaesthesia for pain control in first trimester surgical abortion

BACKGROUND

Abortions prior to 14 weeks are among the most common outpatient surgical procedures performed on people capable of becoming pregnant. Various methods have been used to control pain; however, many people still experience pain with the procedure.

OBJECTIVES

To evaluate the benefits and harms of local anaesthesia given for pain control during surgical abortion at less than 14 weeks' gestation.

SEARCH METHODS

We searched CENTRAL (Ovid EBM Reviews), MEDLINE (Ovid), Embase, POPLINE, and Google Scholar to December 2022 for randomized controlled trials of pain control in surgical abortion at less than 14 weeks' gestation using suction aspiration. We searched the reference lists of related reviews and articles.

SELECTION CRITERIA

We selected effectiveness and comparative effectiveness randomized controlled trials that studied local anaesthesia with common local anaesthetics and administration routes given for pain control in surgical abortion at less than 14 weeks' gestation using uterine aspiration. Outcomes included intraoperative pain, patient satisfaction, and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We computed mean differences (MD) with 95% confidence intervals (CI) for continuous variables reporting a mean. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

Thirteen studies with 1992 participants met the inclusion criteria. Due to heterogeneity of interventions, we could not pool more than two studies for any outcome. We used 13 mm improvement on a visual/verbal analogue scale to indicate a clinically meaningful difference in pain with surgical abortion (pain with dilation, aspiration, or during procedure). Based on type of pain control, we divided studies into three groups. Paracervical block (PCB) effectiveness trials A 20 mL 1% lidocaine PCB reduced pain with dilation (MD -37.00, 95% CI -45.64 to -28.36), and aspiration (MD -26.00, 95% CI -33.48 to -18.52) compared to a sham PCB (1 RCT, 120 participants; high-certainty evidence). A PCB with 14 mL of 1% chloroprocaine resulted in a slight reduction in pain with aspiration compared to a PCB with normal saline injected at two or four sites (MD -1.50, 95% CI -2.45 to -0.55; 1 RCT, 79 participants; high-certainty evidence). PCB comparative effectiveness trials An ultracaine PCB probably results in little to no clinically meaningful difference in pain during procedure compared to topical cervical lidocaine spray (median 1 point higher, interquartile range (IQR) 0 to 3; P < 0.001; 1 RCT, 48 participants; moderate-certainty evidence). A 1000 mg dose of intravenous paracetamol probably does not decrease pain as much as ultracaine PCB during procedure (median 2 points higher, IQR 1 to 3; P < 0.001; 1 RCT, 46 participants; moderate-certainty evidence). Various local anaesthetics in PCB comparative effectiveness trials A 10 mL buffered 2% lidocaine PCB probably does not result in a clinically meaningful difference in pain with dilation compared to a plain lidocaine PCB (MD -0.80, 95% CI -0.89 to -0.71; 1 RCT, 167 participants; moderate-certainty evidence). A buffered lidocaine PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to plain lidocaine PCB (MD -0.57, 95% CI -1.01 to -0.06; 2 RCTs, 291 participants; moderate-certainty evidence). Non-PCB local anaesthesia or PCB technique effectiveness trials PCB: waiting versus no waiting Waiting three to five minutes between 1% lidocaine PCB injection and dilation probably does not result in a clinically meaningful difference in pain with dilation compared to not waiting (MD -0.70, 95% CI -1.23 to -0.17; 2 RCTs, 357 participants; moderate-certainty evidence). Topical cervical analgesia Topical 10 mL 2% lignocaine gel probably does not result in a clinically meaningful difference in pain with aspiration compared to KY Jelly (MD -0.87, 95% CI -1.60 to -0.14; 1 RCT, 131 participants; moderate-certainty evidence). In participants who also received a PCB, 20 mg topical cervical lidocaine spray probably does not result in a clinically meaningful difference in pain during the procedure compared to two pumps of normal saline spray (median -1 point, IQR -2 to -1; P < 0.001; 1 RCT, 55 participants; moderate-certainty evidence). Intravenous paracetamol 1000 mg compared to two pumps of cervical lidocaine spray probably does not results in a clinically meaningful difference in pain procedure (median 1 point, IQR -2 to 2; P < 0.001; 1 RCT, 48 participants; low-certainty evidence). Non-PCB local anaesthesia or PCB technique comparative effectiveness trials Depth of PCB The evidence suggests that a 3-cm deep PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to a 1.5-cm deep PCB (MD -1.00, 95% CI -1.09 to -0.91; 2 RCTs, 229 participants; low-certainty evidence). PCB: four sites versus two sites A two-site (4-8 o'clock) 20 mL 1% lidocaine PCB does not result in a clinically meaningful difference in pain with dilation compared to a four-site (2-4-8-10 o'clock) PCB (MD 8.60, 95% CI 0.69 to 16.51; 1 RCT, 163 participants; high-certainty evidence). Overall, participants reported moderately high satisfaction with pain control and studies reported few adverse events.

AUTHORS' CONCLUSIONS

Evidence from this updated review indicates that a 20 mL 1% plain lidocaine PCB decreases pain during an abortion procedure. Evidence supports forgoing buffering lidocaine and a wait time between PCB injection and cervical dilation. A 1.5-cm deep injection as opposed to a 3-cm deep injection is sufficient. A two-site PCB injection as opposed to a four-site injection has similar effectiveness. Topical cervical anaesthesia (10 mL 2% lignocaine gel or 20 mg topical cervical lidocaine spray) as compared to placebo did not decrease pain based on moderate-certainty evidence, but then when compared to PCB, pain control was similar. Due to this inconsistency in evidence regarding the effectiveness of topical anaesthesia, its routine use is presently not supported. This review did not include studies of pain management with conscious sedation but, based on the results of our prior Cochrane review and the 2022 WHO guidelines, we recommend that the option of combination of pain management using conscious sedation plus PCB and non-steroidal anti-inflammatory drugs should be offered where conscious sedation is available as it further decreases pain.

Equal mixture of 2% lidocaine with adrenaline and 0.5% bupivacaine 20 mL provided faster onset of complete conduction blockade during ultrasound-guided supraclavicular brachial plexus block than 20 mL of 0.5% bupivacaine alone: a randomized double-blinded clinical trial

INTRODUCTION

Recent evidence has questioned the advantage of local anesthetic (LA) combinations. This study tested the hypothesis that mixing rapid-onset (lidocaine) and long-duration (bupivacaine) LA would provide faster onset of complete conduction blockade (CCB) compared with bupivacaine alone and longer duration of analgesia compared with lidocaine alone during low-volume (20 mL) ultrasound-guided (USG) supraclavicular brachial plexus block (SCBPB).

METHODS

Sixty-three patients receiving USG-SCBPB were randomly allocated into: group L: 20 mL 2% lidocaine with epinephrine 1:200 000; group B: 20 mL 0.5% bupivacaine; group LB: 20 mL of equi-volume mixture of both drugs. Sensory and motor blockade was recorded on a three point sensory and motor assessment scale at 10 min intervals for up to 40 min and the total composite score (TCS) at each time point was determined. The duration of analgesia was also noted.

RESULTS

The mean time to CCB of group LB (16±7 min) was comparable (p>0.05) with group L (14±6 min) and group B (21±8 min) in patients who were attained CCB. However, the proportion of patients attaining complete conduction block (TCS=16/16) was significantly lower (p=0.0001) in group B (48%) when compared with group L (95%) and group LB (95%) at the end of 40 min. The median (IQR) duration of postoperative analgesia was longest in group B; 12.2 (12-14.5) hours, followed by group LB 8.3 (7-11) hours and 4 (2.7-4.5) hours in group L.

CONCLUSION

At 20 mL LA volume, equal mixture of lidocaine and bupivacaine provided significantly faster onset of CCB compared with bupivacaine alone and longer duration of postoperative analgesia compared with lidocaine alone but shorter than bupivacaine alone during low-volume USG-SCBPB.

TRIAL REGISTRATION NUMBER

CTRI/2020/11/029359.

Strategies to reduce ileus after colorectal surgery: A qualitative umbrella review of the collective evidence

BACKGROUND

Various strategies were proposed to reduce postoperative ileus after colorectal surgery. This umbrella review aimed to provide a comprehensive overview of current evidence on measures to reduce the incidence and severity of postoperative ileus after colorectal surgery.

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant systematic search was conducted in PubMed and Scopus to identify systematic reviews that assessed the efficacy of interventions used to prevent postoperative ileus after colorectal surgery. Data on study characteristics, interventions, and outcomes were summarized in a narrative manner.

RESULTS

A total of 26 systematic reviews incorporating various strategies like early oral feeding, gum chewing, coffee consumption, medications, and acupuncture were included. Early oral feeding reduced postoperative ileus and accelerated bowel function return. The most assessed intervention was chewing gum, which was associated with a median reduction of postoperative ileus by 45% (range, 11%-59%) and shortening of the time to first flatus and time to defecation by a median of 11.9 and 17.7 hours, respectively. Coffee intake showed inconsistent results, with a median shortening of time to flatus and time to defecation by 1.32 and 14.45 hours, respectively.

CONCLUSION

Early oral feeding, chewing gum, and alvimopan were the most commonly assessed and effective strategies for reducing postoperative ileus after colorectal surgery. Medications used to reduce postoperative ileus included alvimopan, intravenous lidocaine, dexamethasone, probiotics, and oral antibiotics. Intravenous dexamethasone and lidocaine and oral probiotics helped hasten bowel function return. Acupuncture positively impacted the recovery of bowel function.

Practical Use of Self-Adjusted Nitrous Oxide During Transrectal Prostate Biopsy: A Double-Blind Randomized Controlled Trial

PURPOSE

Transrectal prostate biopsy is a common ambulatory procedure that can result in pain and anxiety for some men. Low-dose, adjustable nitrous oxide is increasingly being used to improve experience of care for patients undergoing painful procedures. This study seeks to evaluate the efficacy and safety of low-dose (<45%) nitrous oxide, which has not been previously established for transrectal prostate biopsies.

MATERIALS AND METHODS

A single-institution, prospective, double-blind, randomized, controlled trial was conducted on patients undergoing transrectal prostate biopsies. Patients were randomized to receive either self-adjusted nitrous oxide or oxygen, in addition to routine periprostatic bupivacaine block. Nitrous oxide at levels between 20% and 45% were adjusted to patients' desired effect. Patients completed a visual analog scale for anxiety, State Trait Anxiety Inventory, and a visual analog scale for pain immediately before and after biopsy. The blinded operating urologist evaluated ease of procedure. Periprocedural vitals and complications were assessed. Patients were allowed to drive home independently.

RESULTS

A total of 133 patients received either nitrous oxide (66) or oxygen (67). There was no statistically significant difference in the primary anxiety end point of State Trait Anxiety Inventory or the visual analog scale for anxiety scores between the nitrous oxide and oxygen groups. However, patients in the nitrous oxide group reported significantly lower visual analog scale for pain scores compared to the oxygen group (P = .026). The operating urologists' rating of tolerance of the procedure was better in the nitrous oxide group (P = .03). There were no differences in biopsy performance time. Complications were similarly low between the 2 groups.

CONCLUSIONS

Patient-adjusted nitrous oxide at levels of 20% to 45% is a safe adjunct during transrectal prostate biopsy. Although there was not an observed difference in the primary end point of anxiety, nitrous oxide was associated with lower patient-reported pain scores.

Outcomes of Abdominoplasty in Tumescent Local Anesthesia Combined with Subdural Anesthesia

BACKGROUND

Abdominoplasty is a common surgical procedure performed under general anesthesia, and although the use of TLA combined with subdural anesthesia has never been reported in abdominoplasty, it offers several benefits such as safe and effective local anesthesia and vasoconstriction. We outline our experience with the TLA technique for primary abdominoplasty over the last 7 years.

METHODS

From 2014 to 2021, TLA and subdural anesthesia have been used in primary abdominoplasty surgeries for 106 patients. The TLA solution consisted of 25 mL of 2% lidocaine, 8 mEq of sodium bicarbonate, and 1 mL of epinephrine (1 mg/1 mL) diluted in 1000 mL of 0.9% saline solution. The solution was then injected with a 2-mm cannula into the subcutaneous adipose tissue in the suprafascial plane. The subdural anesthesia was performed at intervertebral level L1-L2 using Ropivacaine 15/18 mg in 4 ml.

RESULTS

Patients aged from 32 to 75 years. The amount of tumescent solution infiltrated ranged between 500 and 1000 mL. Mean surgery time was 70 minutes, and recovery room time averaged at 240 minutes. Major complications related to the surgery were observed in 12.26% of patients, including eight hematomas and five seromas. Two patients experienced wound dehiscence, and no dystrophic scar formation was observed. Eventually, there was no need for a conversion to general anesthesia.

CONCLUSIONS

Tumescent local anesthesia combined with subdural anesthesia is a highly effective and safe method for performing abdominoplasty. This technique has proven to be an excellent choice for primary abdominoplasty, providing significant benefits to patients and surgeons alike due to its safe administration, precise pain management during and after surgery, and minimal postoperative side effects.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

An overview of local anesthetics in over-the-counter products

Over-the-counter (OTC) local anesthetics have historically been used to alleviate pain in several common conditions including toothache and sore throat. With a rise in chronic conditions and an aging population, there has been an increase in associated chronic pain-related disorders. Individuals with chronic pain often seek OTC treatments for quick and accessible pain relief. There are several common OTC local anesthetics, including benzocaine, lidocaine, and dibucaine, which are readily available to patients in several formulations. In order to appropriately advise patients on the use of local anesthetics, it is important to understand their key characteristics, including the mechanism of action, clinical properties, pharmacokinetics, clinical applications, and adverse reactions, which may occur.

Airway topicalization in pediatric anesthesia: An international cross-sectional study

BACKGROUND

There is no national or international consensus or guideline on recommended dosing of lidocaine for airway topicalization in children. Doses quoted in the literature vary substantially.

AIMS

The primary aim of the study was to ascertain current international dosing practices (mg.kg-1 and concentration of solution) for lidocaine airway topicalization in children. The secondary aims included examining aftercare instructions for those receiving lidocaine airway topicalization and instances of local anesthetic systemic toxicity secondary to the use of lidocaine for airway topicalization in pediatric patients.

METHODS

This cross-sectional study consisted of 11-20 questions across three domains-population demographics, clinical practice, and local anesthetic systemic toxicity. It adhered to the consensus-based checklist for reporting of survey studies. Responses were collected over 14 weeks using a combination of probability (cluster and simple random) and nonprobability (purposive, convenience and snowball) sampling. Data were analyzed based on the response rate per question with proportions expressed as percentages and nonparametric data expressed as median (interquartile range [range]) in an effort to minimize nonresponse error. No weighting of items or propensity scoring was applied.

RESULTS

After initial exclusions, 1501 participants from 69 countries, across six continents, were included. Consultant anesthetists or those with an equivalent level of experience accounted for 1262/1501 (84.1%) of responses. Results showed heterogeneity in dosing and timing regimens and evidence that dosing may contribute to adverse outcomes. The maximum dose reported by participants who use lidocaine for airway topicalization as part of their normal practice was 5 mg.kg-1 (4-6 mg.kg-1 [0.5-50]) median (interquartile range [range]) over 2 h (1-4 h [0-30]).

CONCLUSION

The results support the need for further research and consensus in this area, in order to provide safe provision of lidocaine airway topicalization in children. It is hoped the results of this study can support future collaborative work in this area.

Rapid dissolution microneedle based on polyvinyl alcohol/chitosan for local oral anesthesia

At present, the main clinical methods of oral local anesthesia are direct injection of anesthetic and surface ointment. However, the pain and fear caused by the injection, the discomfort of topical anesthetic creams, and the scour and moist oral environment during the procedure pose great challenges to oral anesthesia. Herein, we designed a Lido-PVP/PVA DMNP microneedle (MN) for oral local anesthesia. The microneedle tip was consisted of Polyvinylpyrrolidone/Polyvinyl alcohol (PVP/PVA), which can quickly dissolve and release the lidocaine hydrochloride (Lido) drug within 5 min to achieve rapid anesthesia. The backing was composed of polyvinyl alcohol/chitosan (PVA/CS), and its excellent adhesion can overcome saliva erosion and anchor firmly to the oral mucosa, significantly improving the utilization rate of drugs, as well as the patient compliance. MNs have good mechanical properties for tissue insertion while possessing high drug loading (3 mg/MNs). Von Frey tests proved that MNs showed a faster and more effective local anesthetic effect (anesthesia takes effect at 5 min) compared to cream (anesthesia takes effect at 30 min). In addition, the excellent biocompatibility and no skin irritation endowed Lido-PVP/PVA DMNP MNs a great potential for oral local anesthesia in the oral cavity.

Low-Concentration Brachial Plexus Block

PURPOSE

We devised a low-concentration brachial plexus block (LCBB) that allows for intraoperative, active motion by blocking only sensory nerves. This study evaluated the efficacy of the LCBB.

METHODS

Thirty-eight patients (14 men and 24 women; mean age, 60.0 years) underwent surgery with the LCBB. An ultrasound-guided supraclavicular brachial plexus block with 30-40 mL of 0.6 mg/ml ropivacaine hydrochloride hydrate was performed approximately 2 hours before starting the surgery. A local anesthetic (LA) was administered as a local infiltration if the intraoperative pain relief was locally insufficient. The surgery was performed using a tourniquet as usual, which was released for approximately 1 minute when there was a requirement to check for intraoperative, active motion. We recorded the waiting time required between LCBB administration and surgery, the total surgery time, the total tourniquet time, the number of patients administered an LA, the total LA volume (1% lidocaine equivalent), and the muscle strength at intraoperative, active motion (evaluated by manual muscle testing and categorized as ≥grade 4 or ≤grade 3).

RESULTS

The mean waiting time was 137.0 minutes, the mean surgery time was 124.6 minutes, and the mean tourniquet time was 70.6 minutes. In 2 patients, the anesthetic effect was not achieved, and we switched to other methods of anesthesia (1 patient was switched to an intravenous, regional anesthesia; 1 patient was switched to a standard brachial plexus block). Excluding those 2 cases, the mean LA volume was 8.7 mL among 22 cases (61.1%), and 33 cases (91%) had manual muscle testing of ≥grade 4. In 36 of 38 cases (94.7%), surgery could be performed by LCBB.

CONCLUSIONS

Although an LCBB may require additional LA, it is a useful anesthesia method that allows intraoperative active motion and tourniquet use.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Anatomic Location Influences Duration of Local Lidocaine Anesthesia in Dermatologic Surgery

BACKGROUND

Although the onset and duration of local anesthetics are well-defined, how the anatomic site influences the duration of local anesthetics has not been well characterized in dermatology.

OBJECTIVE

To define the duration of local anesthesia by anatomic site.

MATERIALS AND METHODS

This was a prospective study. Adult healthy volunteers and patients undergoing Mohs micrographic surgery were invited to participate. The nose and the shin were chosen to represent highly and poorly vascularized anatomic sites, respectively. A total of 0.5 mL of buffered 1% lidocaine hydrochloride with 1:100,000 epinephrine was injected subcutaneously into each anatomic site of each participant. A pinprick test was used to assess adequate anesthesia until return of baseline sensation or visit completion.

RESULTS

This study enrolled 25 participants. Time to return of sensation was significantly shorter on the nose compared with the shin ( p < .0001). On the nose, there was an association between male sex and shorter time to return of sensation.

CONCLUSION

Time to return of sensation is significantly shorter on the nasal ala compared with the shin, suggesting that patients may regain sensation sooner on highly vascularized sites. Defining the duration of local anesthetics based on anatomic regions is important for treatment planning in dermatologic procedures.

Drugs detection in fingerprints

Fingerprints left at a crime scene are used to connect the crime to a person who may have been present there. Fingerprints can also be used as alternative material in forensic toxicology. The detection of drugs in fingerprint samples can be used to show that an individual touching an item has consumed specific drugs. The aim of this study was to check the usefulness of fingerprints in drug analyses and detection of some analytes in this material. Fingerprint samples were collected on glass slides from a volunteer who consumed separately tablets containing pseudoephedrine, codeine, dextromethorphan, and used lidocaine spray. Moreover, fingerprints of individuals receiving sertraline, hydroxyzine and trazodone as part of their long-term treatment were analysed. The detection of drugs was conducted using the liquid chromatography tandem mass spectrometry (LC-MS/MS) technique. After administration of single doses of drugs, they were detected up to 36 h (pseudoephedrine), 24 h (codeine), and less than 6 h (dextromethorphan and lidocaine) with maximum concentrations observed at 1-4 h. In fingerprints of a person who has finished treatment with hydroxyzine and sertraline it was possible to detect these drugs even 20 days after last drug administration. Cetirizine (hydroxyzine metabolite) and mCPP (trazodone metabolite) were determined in fingerprints of individuals under long-term treatment. This work has demonstrated that forensic toxicology can use fingerprints as alternative material. Drugs can be detected in fingerprints even after their single doses. Parent compounds predominate over metabolites in the fingerprints. The detection window depends on the type of drug and duration of the treatment.

Topical and subconjunctival anesthesia versus topical anesthesia alone in patients with senile cataracts undergoing phacoemulsification: a double-blind randomized controlled trial

BACKGROUND

This study compared topical anesthesia to a combination of topical anesthesia and subconjunctival anesthesia for phacoemulsification.

METHODS

This double-blinded parallel placebo-controlled randomized trial involved senile cataract patients scheduled for phacoemulsification between May and December 2022. Patients were randomly assigned to receive either topical anesthesia with 0.5% tetracaine hydrochloride and subconjunctival balanced salt solution injection (Control group) or topical anesthesia and subconjunctival injection with 2% lidocaine (Lidocaine group). Baseline parameters, cataract grades, and various outcomes were recorded, including pain scores at specific time points, patient cooperation scores, requests for additional anesthesia, and complications. Statistical methods included Fisher's exact test, the t-test, ordinal logistic regression, and linear regression with robust standard errors.

RESULTS

In total, 176 patients were included in the study after excluding 33 patients. A significant reduction in immediate postoperative pain was achieved in the Lidocaine group (p < 0.001) and was maintained for 2 h (p = 0.011). Additionally, better cooperation was observed in this group (p = 0.038). However, patients in the Lidocaine group experienced more pain during the subconjunctival injection (p = 0.001) and a significant increase in subconjunctival hemorrhage related to the injection (p < 0.001). Despite this, the rates of surgical complications were comparable between the groups, and all phacoemulsification procedures were successfully completed using the assigned anesthetic technique.

CONCLUSIONS

The addition of subconjunctival lidocaine injection to topical anesthesia reduced postoperative pain and improved patient cooperation during phacoemulsification. However, the lidocaine injection was painful, and it carried a higher risk of spontaneous-relief subconjunctival hemorrhage.

TRIAL REGISTRATION

Trial Registration Number: TCTR20220804003, date of registration August 4, 2022, retrospectively registered.

Fabrication of lidocaine-loaded polymer dissolving microneedles for rapid and prolonged local anesthesia

There is an urgent need for research into effective interventions for pain management to improve patients' life quality. Traditional needle and syringe injection were used to administer the local anesthesia. However, it causes various discomforts, ranging from brief stings to trypanophobia and denial of medical operations. In this study, a dissolving microneedles (MNs) system made of composite matrix materials of polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), and sodium hyaluronate (HA) was successfully developed for the loading of lidocaine hydrochloride (LidH). The morphology, size and mechanical properties of the MNs were also investigated. After the insertion of MNs into the skin, the matrix at the tip of the MNs was swelled and dissolved by absorption of interstitial fluid, leading to a rapid release of loaded LidH from MNs' tips. And the LidH in the back patching was diffused into deeper skin tissue through microchannels created by MNs insertion, forming a prolonged anesthesia effect. In addition, the back patching of MNs could be acted as a drug reservoir to form a prolonged local anesthesia effect. The results showed that LidH MNs provided a superior analgesia up to 8 h, exhibiting a rapid and long-lasting analgesic effects. Additionally, tissue sectioning and in vitro cytotoxicity tests indicated that the MNs patch we developed had a favorable biosafety profile.

Regional versus systemic dexmedetomidine as an adjuvant to lidocaine for intravenous regional anaesthesia in healthy volunteers: a randomized crossover study

BACKGROUND

Dexmedetomidine enhances the quality and duration of lidocaine intravenous regional anaesthesia (IVRA). However, the two administration routes have not been directly compared regarding effects on tourniquet tolerance time with lidocaine IVRA. Additionally, it remains unclear whether the prolonged tourniquet tolerance stems from the direct peripheral action of dexmedetomidine or indirect systemic analgesic effects.

METHODS

We conducted forearm IVRA in 12 healthy volunteers using a crossover design on two separate study days. One day, the systemic dexmedetomidine group received an intravenous infusion of 0.5 μg/kg dexmedetomidine (20 mL) in one arm, followed by 0.5% lidocaine (25 mL) forearm IVRA in the contralateral arm. On the other day, the regional dexmedetomidine group received an intravenous 0.9% saline infusion (20 mL) in one arm, followed by combined 0.5% lidocaine (25 mL) and 0.5 μg/kg dexmedetomidine forearm IVRA in the opposite arm. After a two-week washout period, participants crossed over to receive the alternate treatment. The primary outcome was tourniquet tolerance time, from initiating IVRA until the patient-reported tourniquet pain numerical rating scale exceeded three.

RESULTS

The tourniquet tolerance time was longer with regional versus systemic dexmedetomidine (36.9 ± 7.6 min vs 23.3 ± 6.2 min, respectively), with a 13.6 min mean difference (95% CI: 10.8 to 16.4 min, p < 0.001). Regional dexmedetomidine also hastened sensory onset and extended sensory recovery compared to systemic administration. Delayed sedation after tourniquet release occurred in 5 of 12 subjects receiving regional dexmedetomidine.

CONCLUSION

The addition of regional dexmedetomidine to lidocaine prolonged tourniquet tolerance time in forearm IVRA to a greater extent compared to systemic dexmedetomidine in healthy volunteers.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2300067978.

Analgesic effect of linalool odor on oral ulcerative mucositis-induced pain in rats

Oral ulcerative mucositis (OUM) induces severe pain, leading to a low quality of life. Linalool odor exposure has recently been reported to suppress inflammatory pain in the hind paws. However, the analgesic effect of linalool odor on orofacial pain remains unclear. In this study, we examined the mechanism underlying the analgesic effect of linalool odor on oral pain caused by OUM using nocifensive behavioral and immunohistochemical analyses in rats. OUM was developed by treating the labial fornix region of the inferior incisors with acetic acid. Linalool at 1% was exposed for 5 min at 30 min before nocifensive behavioral measurements. OUM induced spontaneous pain and mechanical allodynia, which were suppressed by the linalool odor. Mechanical allodynia in the hind paw following the injection of complete Freund's adjuvant was also suppressed by linalool odor. Application of lidocaine to the olfactory bulb attenuated the inhibition of spontaneous pain and hyperactivation of trigeminal spinal nucleus caudalis neurons in OUM model rats. Linalool odor exposure-induced neuronal activation in the locus coeruleus (LC) of OUM model rats was decreased by lidocaine application to the olfactory bulb. The decrease in neuronal activation in the LC was attenuated by the administration of orexin 1 receptor (OX-1) antagonist to the LC. These results suggest that linalool odor stimulation through the olfactory pathway activates LC neurons via OX-1 signaling, leading to the suppression of OUM-induced oral pain.

Pharmacokinetics of intravenous and topical lidocaine in patients undergoing thoracoscopic pulmonary resection: a comparative study

OBJECTIVE

Lidocaine was the commonly used local anesthetic. The present study aimed to compare the pharmacokinetics of intravenous and topical lidocaine in patients undergoing thoracoscopic pulmonary resection.

PATIENTS AND METHODS

Sixty patients who were scheduled for thoracoscopic pulmonary resection were screened and randomly assigned to the intravenous lidocaine group and topical lidocaine group. After induction, the patient in the intravenous group was given an intravenous bolus of 1.5 mg/kg lidocaine, while the patient in the topical group was given 3.0 mg/kg lidocaine via the "spray-as-you-go" method. Arterial blood was sampled at preset intervals, and plasma concentrations of lidocaine and its metabolites [monoethylglycinexylidide (MEGX) and glycinexylidide (GX)] were measured by ultra-performance liquid chromatography-tandem mass spectrometry.

RESULTS

Following intravenous administration, plasma lidocaine concentration reached its peak with a time to reach Cmax (Tmax) of 0.05 h and then decreased in a biphasic manner with a very short half-life time (T1/2) of 1.85 h. After topical administration, lidocaine was well absorbed, with Tmax of 0.21 h and bioavailability of 71.02%. The mean Tmax, Cmax, and area under the curve from the time (AUC0-t) of MEGX and GX were higher in the topical group than in the intravenous group. There were no obvious differences in the Cmax, T1/2, clearance, or apparent volume of distribution of lidocaine between the two groups. No obvious adverse events were observed.

CONCLUSIONS

Topical administration of 3 mg/kg lidocaine via the "spray-as-you-go" method is an effective and safe technology for patients undergoing thoracoscopic pulmonary resection.

Evaluation of lidocaine administration into the ovarian pedicle for the control of intraoperative and early postoperative pain during ovariohysterectomy in dogs

OBJECTIVE

To evaluate effects of lidocaine 2% administration into the ovarian pedicle on intraoperative nociception and early postoperative pain in dogs undergoing ovariohysterectomy.

STUDY DESIGN

Prospective, randomized, blinded clinical study.

ANIMALS

A total of 20 healthy adult female dogs of different breeds.

METHODS

Dogs were premedicated with acepromazine (0.02 mg kg-1) and morphine (0.5 mg kg-1) intramuscularly, anesthesia induced with propofol and maintained with isoflurane. Dogs were randomly assigned to be administered 2 mL of saline (group S) or lidocaine 2% (group L) into the mesovarium (1 mL each side). Heart rate (HR) and noninvasive systemic arterial pressure were recorded before surgery (T0), before (T1) and during ligation of the right ovarian pedicle (T2), before (T3) and during ligation of the left ovarian pedicle (T4). Rescue treatment (propofol) was administered if HR or systolic arterial pressure (SAP) increased by 20% compared with the previous time point. Pain, assessed with the Glasgow Composite Measure Pain Scale-Short Form (CMPS-SF) was recorded before premedication (baseline) and after extubation. Administration of postoperative rescue analgesia was recorded.

RESULTS

In group S, HR was higher at T2 than T1 (112 ± 18 versus 89 ± 21 beats minute-1, p = 0.001) There were no significant differences between treatments at any time. SAP was higher at T2 than T1 in group S (110 ± 12 versus 100 ± 10 mmHg, p = 0.031). SAP was higher in group S than group L at T3 (113 ± 12 and 91 ± 10 mmHg, respectively, p = 0.001). No dogs required propofol intraoperatively. All dogs required postoperative rescue analgesia. Compared with baseline, CMPS-SF increased 60 minutes after extubation (group S; p = 0.019, group L; p = 0.043).

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of lidocaine 2% into the mesovarium did not reduce intraoperative nociception and did not improve postoperative analgesia.

Evaluation of the addition of adrenaline in a bilateral maxillary nerve block to reduce hemorrhage in dogs undergoing sharp staphylectomy for brachycephalic obstructive airway syndrome. A prospective, randomized study

OBJECTIVE

To assess the use of adrenaline (0.00198%) in a bilateral maxillary nerve block to reduce intraoperative hemorrhage in dogs undergoing staphylectomy for the treatment of brachycephalic obstructive airway syndrome (BOAS).

STUDY DESIGN

Prospective, randomized, double-blinded controlled study.

SAMPLE POPULATION

A total of 32 client owned, clinically affected dogs undergoing a cut and sew sharp staphylectomy for treatment of BOAS. A total of 16 dogs randomly assigned to adrenaline (A) group and 16 to no-adrenaline (NA) group.

METHODS

A bilateral maxillary nerve block was performed in all dogs prior to staphylectomy using lidocaine alone (group NA) or a combination of lidocaine and adrenaline (group A). Total hemorrhage was measured by weighing cotton-tipped applicators and swabs used on precision scales. In addition, a semi-quantitative hemorrhage score (1-5) was determined. Dogs were monitored for intraoperative hemodynamic stability during the procedure.

RESULTS

Total hemorrhage was significantly (p = .013) lower in group A compared with group NA. The median semi-quantitative hemorrhage score was significantly lower for group A (p = .029) compared with group NA. No significant adverse effects were noted due to adrenaline usage.

CONCLUSION

This study demonstrated that the use of adrenaline in a bilateral maxillary nerve block results in significantly lower intraoperative hemorrhage during cut and sew sharp staphylectomy and appeared safe to use.

CLINICAL SIGNIFICANCE

Potential clinical advantages include improved visualization, prevention of unnecessary blood loss and reduction in risk of blood aspiration.

Examination of the Rate and Extent of Drug Released from Commercial Topical Delivery Systems During Wear: An Example with Lidocaine Topical Systems

OBJECTIVE

This study aimed to determine the extent and rate of lidocaine released in vivo from two bioequivalent topical delivery systems (TDS) by using complementary assessments: pharmacokinetic analysis in healthy human volunteers, and residual lidocaine in TDS following 12 h of wear. The goal was to explore a potentially more clinically meaningful strength presentation than percent active pharmaceutical ingredient loaded in topical systems.

METHODS

A three-arm, open-label, crossover clinical study was conducted in 23 human subjects, with 5% lidocaine topical systems from two manufacturers, and intravenous lidocaine administration. Residual drug and LC-MS/MS analyses were performed on worn TDS and serum samples. The rate and extent of drug released from the TDS during wear were determined through (1) calculations of consumed lidocaine via analysis of residual drug in worn TDS, and (2) a pharmacokinetic approach via derivation of the absolute clearance and serum lidocaine concentration at steady state.

RESULTS

Overall the pharmacokinetic approach underestimated the amount transferred to the subject and exhibited greater variability, which may relate to natural inter-subject variability in pharmacokinetic parameters. Further, lidocaine TDS are intended for localized, not systemic, delivery and this may also explain some of the variability seen in the systemic serum concentrations.

CONCLUSIONS

The residual drug and pharmacokinetic approaches align well for transdermal formulations, but the differences in administration route (topical versus transdermal) all but eliminates the potential use of the pharmacokinetic approach unless additional compartmental modeling is explored.

Liposomal and Nonliposomal Bupivacaine for Mohs Surgery: A Systematic Review

BACKGROUND

Lidocaine is the most commonly used local anesthetic for Mohs micrographic surgery (MMS), but given its limited half-life, postoperative pain remains a significant concern for patients. Bupivacaine is used in various surgical subspecialty procedures and has demonstrated improved pain control compared with lidocaine. However, its role in MMS is insufficiently explored.

OBJECTIVE

To systematically review the current literature for reports on use of bupivacaine, traditional nonliposomal and newer liposomal formulations, for MMS.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. The MEDLINE, PubMed, and EMBASE databases were queried for articles presenting original data on the use of bupivacaine for MMS.

RESULTS

Of 483 potentially relevant articles, 3 studies met final inclusion criteria, capturing a total of 253 patients involved in primary investigations comparing bupivacaine to traditional local anesthesia for MMS. Bupivacaine was well-tolerated and associated with comparable or modestly reduced intraoperative and postoperative pain and opioid use.

CONCLUSION

Bupivacaine may have a role in prolonging intraoperative anesthesia, reducing acute postoperative pain, and reducing postoperative opioid use after MMS. However, large, prospective studies are needed to solidify the generalizability and clinical utility of these findings.