Subcutaneous Injection Of Lidocaine Research Articles

Non-Operating Room Anesthesia (NORA) for Ultrasound-Guided Liver Radiofrequency Ablation.

Percutaneous ultrasound-guided radiofrequency ablation (RFA) is a well-studied treatment option for locally non-advanced hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLMs). Sedation is of crucial interest as it enables safe and pain-free procedures. Whether the type of sedation has an impact on procedural outcome is still not well investigated. We retrospectively collected data on patients undergoing liver RFA for various oncological conditions. Procedures were conducted in a non-operating room anesthesia (NORA) setting. Procedural-related complications and short-term oncological outcomes were analyzed. Thirty-five patients (mean age 71.5 y, 80% male) were treated for HCC (26), CRLM (6) and gastric cancer metastases (3). Mean lesion size was 21 mm (SD ± 10.1 mm), and the most common tumor localization was the right hepatic lobe. RFA was performed in a step-up sedation approach, with subcutaneous lidocaine injection prior to needle placement and subsequent deep sedation during ablation. No anesthesia-related early or late complications occurred. One patient presented with pleural effusion due to a large ablation zone and was treated conservatively. Local tumor-free survival after 1 and 6 months was 100% in all cases where a curative RFA approach was intended. NORA for liver RFA comes with high patient acceptance and tolerance, and optimal postoperative outcomes and oncologic results.

Comparison of Pain With Ultrasound-Guided Intra-Articular Hip Injections With and Without Prior Subcutaneous Local Anesthesia.

To compare pain levels of intra-articular hip steroid injections performed with and without prior subcutaneous local anesthesia (LA) injection. Randomized prospective study. University-based musculoskeletal clinic. Forty-one adult patients undergoing a first-time ultrasound-guided unilateral intra-articular hip steroid injection. Subjects were randomized into 1 of 2 groups: intra-articular hip injection with prior subcutaneous LA with 2 mL of lidocaine 1% (With LA) or hip injection without prior subcutaneous LA (Without LA). Visual analog scale (VAS) pain scores (0-100) were collected before and after each injection. Visual analog scale pain score for the intra-articular hip injection. Of the 41 total subjects, 18 were randomized to the Without LA group and 23 to the With LA group. There was no significant difference in baseline (preprocedure) VAS scores between the Without LA (mean ± SD = 39.2 ± 27.2) and With LA (41.2 ± 24.0) groups (P = 0.864). The mean ± SD VAS score for the subcutaneous LA injection in the With LA group was 20.4 ± 16.1. There was no significant difference in VAS scores for the intra-articular hip injection between the Without LA (48.5 ± 27.7) and With LA (39.5 ± 25.7) groups (P = 0.232). Subcutaneous injection of lidocaine before an intra-articular hip injection did not significantly decrease pain from the intra-articular hip injection. Providers may perform intra-articular hip injections with a 22-gauge 3.5-inch spinal needle without the need for an extra subcutaneous LA injection.

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

BackgroundThe 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.MethodsA 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.ResultsTotal 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.ConclusionDexmedetomidine significantly improves the analgesic quality of WALANT when added to lidocaine with less opioid consumption.Trial registration(ID: PACTR202203906027106; Date: 31/07/2023).

Subcutaneous injection of lidocaine around ischemic ankle provides safe and effective foot analgesia in patients with critical limb ischemia.

It is often difficult to alleviate foot pain associated with critical limb ischemia (CLI) using common analgesics. Neuraxial block is contraindicated in anticoagulant therapy. This study was designed to determine the response to subcutaneous injection of lidocaine around the network of peripheral nerves around the ankle in patients with CLI pain on anticoagulants and antiplatelets. Sixteen patients with CLI pain in the foot were enrolled in this double-blind placebo-controlled crossover study. Patients were randomized to receive either 2% lidocaine or saline via catheters inserted into the subcutaneous area around the ankle. After recurrence of pain, the patients were crossed over to receive the alternative treatment. Pain was assessed with a numerical rating scale (NRS) before and 15min after injection. Patients used a descriptive scale to grade pain control and were asked to determine the duration of analgesia in each arm of the study. No serious complications including protracted bleeding occurred. Lidocaine significantly decreased the NRS on movement from 10 (6, 10) [median (range)] to 2 (0, 10) (p < .001), and the differences in the Δ change in NRS between lidocaine and placebo were significant (p = .009). Of the 16 patients, 14 patients were very satisfied after lidocaine but only one described the same after saline. The effect of lidocaine and placebo lasted 11 (0, 28) and 1 (0, 22) h, respectively. Subcutaneous injection of lidocaine around the ischemic ankle affectively alleviated pain in patients with CLI without serious adverse effects under anticoagulant therapy.

Comparison of EMLA Cream versus Lidocaine Injection for Lumbar Puncture Pain Control in Pediatric Oncology Patients.

Background Subcutaneous lidocaine injection and topical EMLA cream are both used to control lumbar puncture (LP) pain; however, local analgesia usage is not standardized. Methods We conducted a prospective, single-blinded, randomized-controlled crossover trial comparing the two modalities in reducing LP pain. Pediatric patients requiring serial LPs were randomly assigned to receive EMLA cream or lidocaine injection prior to LP. On the subsequent LP, analgesia was defaulted to the other agent. Pain was assessed using the Wong-Baker FACES Pain Rating Scale pre-procedure: 30 to 60 minutes post-LP, and 24 hours post-procedure. Results Ten patients were included in the analysis (median age: 5.5 years). Pain ratings at 1 and 24 hours post-LP did not differ between the two strategies ( p = 0.79). No adverse local reactions were reported for either agent. Conclusion Accordingly, both lidocaine and EMLA cream provided effective LP pain control.

Neonatal Methemoglobinemia After Subcutaneous Injection of Lidocaine to the Mother at Birth.

Neonatal Methemoglobinemia After Subcutaneous Injection of Lidocaine to the Mother at Birth.

Can eye surface temperature be used to indicate a stress response in harbour seals (Phoca vitulina)?

AbstractInfra-red thermography (IRT) is increasingly being used to estimate physiological stress responses in animals via changes in eye surface temperature. The aim of this study was to determine whether eye temperature of harbour seals (Phoca vitulina) changes in response to routine handling and the potentially painful procedure of flipper-tagging, and if responses to tagging can be mitigated by subcutaneous injection of lidocaine. Orphaned pups (n = 52) at a rehabilitation facility were assigned to one of four treatments: Lidocaine (handled twice, once for injection and once for tagging); Saline (also handled twice); Tag Only (handled once); Sham Tag (handled once). Eye temperature increased more when pups were first handled compared to pups that were not handled and increased further in pups that underwent a second handling. Eye temperature of pups that were tagged without any previous treatment (Tag Only) increased compared to pups that were sham-tagged. Eye temperature also tended to increase after pups were injected with lidocaine but not saline. These results suggest that: (i) handling causes a physiological stress response; (ii) increased eye temperature arising from the second handling suggests the first handling was likely aversive, resulting in sensitisation to further handling; (iii) the rise in eye temperature after tagging, but not sham-tagging, may reflect pain from tagging; and (iv) lidocaine, at the dosage tested, did not appear to reduce the physiological response to tagging. These results show promise for the use of eye temperature to monitor stress responses and for evaluating the potential aversiveness of routine procedures in seals.

Subcutaneous Injection of Tranexamic Acid to Reduce Bleeding During Dermatologic Surgery: A Double-Blind, Placebo-Controlled, Randomized Clinical Trial.

Topical application, oral, and IV injection of tranexamic acid (TXA) have been used to reduce surgical bleeding. To evaluate the safety and efficacy of TXA injected subcutaneously to reduce bleeding during dermatologic surgery. In this double-blinded, placebo-controlled, randomized prospective study, 131 patients were randomized to subcutaneous injection of lidocaine 2% diluted 1:1 with either saline (placebo) or TXA 100 mg/1 mL before surgery. Before the second stage or closure, size measurements of bloodstain impregnation on Telfa and surgical wound size were recorded and analyzed using mixed-effects linear regression. Subjective evaluation of hemostasis was performed using 4-point scale grading and analyzed using Fischer's exact test. One hundred twenty-seven patients completed the study. The bloodstain to surgical wound size ratio was smaller in the TXA group (1.77) compared with the placebo group (2.49) (p < .001). An improved effect of TXA on bleeding was observed in the subgroup of patients receiving anticoagulants (mean difference; 95% confidence interval; -0.83; -1.20 to -0.46 p < .001). The subjective hemostasis assessment was significantly better in the TXA group overall (p = .043) and anticoagulant subgroup (p = .001) compared with the placebo group. Subcutaneous injection of TXA was safe, reduced bleeding during dermatologic surgery, and particularly effective for patients receiving anticoagulation treatment.

The difference of subcutaneous digital nerve block method efficacy according to injection location

IntroductionFinger injuries are commonly attended to in the emergency department, and digital nerve block is a frequently performed procedure for such injuries. This study compared the efficacy levels of the subcutaneous method according to the different injection sites. MethodThis was a simulation study for medical students who rendered medical service at the emergency department. One group performed subcutaneous injection of lidocaine at the volar side of the metacarpophalangeal (MCP) joint, while another group injected at the volar side of the proximal interphalangeal (PIP) joint. The time to anesthesia was measured at 30-s intervals. Pain at the injection site was measured using the numeric rating scale (NRS), while the length from the fingertip to the injection site and the circumference of the injection site were measured. ResultsA total of 82 participants were included, with 41 under the MCP joint group and the rest under the PIP joint group. The mean length from the fingertip to the needling point was 3.62 ± 0.63 cm in the PIP joint group and 5.90 ± 0.65 cm in the MCP joint group, while the mean circumference of the needling point was 4.93 ± 0.51 and 5.61 ± 0.58 cm, and the mean time to anesthesia was 2.55 ± 1.11 and 3.79 ± 1.28 min (p-value < 0.001), respectively. The median value of NRS was 4 in both groups (p-value = 0.921). Length was correlated with the time to anesthesia (p-value = 0.018). ConclusionInjection into the PIP joint showed the same anesthetic effect as injection into the MCP joint, but this effect occurred faster in the former.

Comparison of Two Lidocaine Administration Techniques on Perceived Pain From Bedside Procedures: A Randomized Clinical Trial

Lidocaine is used to alleviate procedural pain but paradoxically increases pain during injection. Pain perception can be modulated by non-noxious stimuli such as temperature or touch according to the gate control theory of pain. We postulated that lidocaine dripped onto the skin prior to injection would cool or add the sensation of touch at the skin surface to reduce pain perception from the procedure. A randomized clinical trial of patients referred to the procedure service from February 2011 through March 2015 was conducted. All patients received 1%subcutaneous lidocaine injection. Patients randomized to the intervention group had approximately 1 to 2ml of lidocaine squirted onto the skin surface prior to subcutaneous lidocaine injection. Patients were blinded to the details of the intervention and were surveyed by a blinded investigator to document the primary outcome (severity of pain from the procedure) using a visual analog scale. A total of 481 patients provided consent and were randomized to treatment. There was a significant improvement in the primary outcome of procedural pain (control, 16.6 ± 24.8mm vs12.2 ± 19.4mm; P= .03) with the intervention group as assessed by using the visual analog scale score. Pain scores were primarily improved for peripherally inserted central catheters (control, 18.8 ± 25.6mm vs12.2 ± 18.2mm; P= .02) upon subgroup analysis. Bedside procedures are exceedingly common. Data regarding the severity of procedural pain and strategies to mitigate it are important for the informed consent process and patient satisfaction. Overall, pain reported from common bedside procedures is low, but pain can be further reduced with the addition of lidocaine onto the skin surface to modulate pain perception. ClinicalTrials.gov; No.: NCT01330134; URL: www.clinicaltrials.gov.

Efficacy of subcutaneous lidocaine injection in venous insufficiency: a prospective, randomized, controlled study, and new treatment protocol.

[Purpose] The purpose of this study was to evaluate the efficacy of subcutaneous injection with lidocaine in patients with chronic venous insufficiency in the early stage. [Subjects and Methods] Patients (n=50) randomized to the treatment group received subcutaneous injections from a mixture of physiological saline sterile solution and lidocaine once a week to both legs below the knee for 5 sessions. Patients in the treatment group were also given ankle pumping exercises and compression stockings throughout the treatment. Patients randomized to the control group (n=50) received only ankle pumping exercises and compression stockings. Patients were evaluated using the visual analog scale (VAS) for pain and Chronic Venous Disease Quality of life Questionnaire (CIVIQ-20) for quality-of-life at months 1, 3, 6, at the end of month 12, and at the end of the injection treatment for 5 sessions. [Results] CIVIQ-20 and VAS results were significantly lower in the treatment group, than in the control group at months 1, 3 and 6. However, CIVIQ-20 and VAS results were not significantly different, compared with the pre-operative period at month 12. [Conclusion] We observed that 5-week subcutaneous lidocaine injection treatment was effective in patients who do not respond to oral medical treatment or in whom surgery is not considered.

Pre-emptive ice cube cryotherapy for reducing pain from local anaesthetic injections for simple lacerations: a randomised controlled trial

ObjectiveSubcutaneous local anaesthetic injection can be painful to patients in the ED. We evaluated the effect of cryotherapy by application of an ice cube to the injection site prior to...

When local anesthesia becomes universal: Pronounced systemic effects of subcutaneous lidocaine in bullfrogs (Lithobates catesbeianus)

Sodium channel blockers are commonly injected local anesthetics but are also routinely used for general immersion anesthesia in fish and amphibians. Here we report the effects of subcutaneous injection of lidocaine (5 or 50mgkg−1) in the hind limb of bullfrogs (Lithobates catesbeianus) on reflexes, gular respiration and heart rate (handled group, n=10) or blood pressure and heart rate via an arterial catheter (catheterized group n=6). 5mgkg−1 lidocaine did not cause loss of reflexes or change in heart rate in the handled group, but was associated with a reduction in gular respiratory rate (from 99±7 to 81±17breathsmin−1). 50mgkg−1 lidocaine caused a further reduction in respiratory rate to 59±15breathsmin−1, and led to a progressive loss of righting reflex (10/10 loss by 40min), palpebral reflex (9/10 loss at 70min), and contralateral toe pinch withdrawal (9/10 loss at 70min). Reflexes were regained over 4h. Systemic sedative effects were not coupled to local anti-nociception, as a forceps pinch test at the site of injection provoked movement at the height of the systemic effect (tested at 81±4min). Amphibians are routinely subject to general anesthesia via exposure to sodium channel blockers such as MS222 or benzocaine, however caution should be exercised when using local injectable lidocaine in amphibians, as it appears to dose-dependently cause sedation, without necessarily preventing local nociception for the duration of systemic effects.

Effect of lidocaine with and without epinephrine on lymphatic contractile activity in mice in vivo.

A local anesthetic, lidocaine, is known to affect cutaneous blood flow when injected into the skin. However, it is unknown if dermal lymphatic function can also be affected. Therefore, we characterized lymphatic function in response to administration of lidocaine with and without epinephrine. Non-invasive near-infrared fluorescence imaging (NIRFI) with intradermal injection of indocyanine green (ICG) was used to characterize the lymphatic "pumping" function in mice after subcutaneous injection of 2% lidocaine with and without 1:100,000 epinephrine or saline. NIRFI was performed for 10-20min immediately after and 1, 3, and 5h after these interventions. Lymphatic contraction frequencies significantly decreased 10min after subcutaneous injection of lidocaine and remained plateaued for another 5min, before returning to baseline. However, addition of 1:100,000 epinephrine to 2% lidocaine rapidly increased lymphatic contraction frequencies at 5min post-injection, which returned to baseline levels 15min later. Injection of saline also increased lymphatic contraction frequency 5min after injection, which returned to baseline 10min post-injection. Although lidocaine administration showed a decrease in lymphatic function, the combination of epinephrine with lidocaine resulted in a predominant net effect of increased contractile activity.

EN3427: a novel cationic aminoindane with long-acting local anesthetic properties.

Currently approved local anesthetic drugs provide relatively brief local anesthesia that is appropriate and even desirable in some settings, but an extended duration of action beyond their capabilities would be a distinct benefit in other clinical situations. We implemented a drug discovery program that sought to identify novel local anesthetic molecules that specifically demonstrated a long-acting, preferential action on nociceptor sensory afferents that expressed transient receptor potential (TRP) channels. The hypothesis we tested was whether relatively membrane-impermeant local anesthetic molecules could confer long-lasting anesthesia if neuronal access was facilitated by TRP channel activation. The current work describes in vivo studies on a lead molecule that emerged from the discovery program, EN3427, in several rodent pain models. Studies were performed on male Sprague-Dawley rats using 2 models of acute mechanical paw-pinch-evoked and pinprick-evoked nociceptive pain. Behavioral responses to noxious stimuli were assessed at baseline, that is, before any pharmacologic intervention, and at various timepoints after a single perisciatic or subcutaneous administration of either EN3427 alone or in combination with lidocaine. Paw withdrawal thresholds or cutaneous trunci reflexes were quantified, and pre-post drug values were compared statistically with analysis of variance followed by post hoc Dunnett multiple range test. A single perisciatic injection of lidocaine (2%) produced relief of paw-pinch-evoked pain that was significantly different from baseline through to the 1-hour timepoint (Dunnett multiplicity-adjusted P = 0.0081), as assessed using paw withdrawal or vocalization end points. EN3427 (0.2%), in the same model, produced a long-lasting block, with pain thresholds being significantly above baseline through to the 18-hour timepoint (Dunnett multiplicity-adjusted P = 0.0002); the combination of EN3427 (0.2%) plus lidocaine (2%) produced even longer lasting analgesia, with pain thresholds being significantly above baseline through to the 24-hour timepoint (Dunnett multiplicity-adjusted P = 0.0073). Similar results were obtained with use of the pinprick approach. A single subcutaneous injection of lidocaine (2%) produced complete loss of sensation to cutaneous pinprick through 0.5 hours, but sensitivity thresholds were no different to baseline by the 1-hour timepoint, a similar injection of EN3427 alone (0.2%) produced a loss of sensation that was significantly different from baseline through the 8-hour timepoint (Dunnett multiplicity-adjusted P = 0.0045), and the combination of lidocaine (2%) plus EN3427 (0.2%) appeared to further enhance duration of analgesia, although this was significantly different from baseline only through the 10-hour timepoint (Dunnett multiplicity-adjusted P = 0.0048). Analgesic efficacy was dose related; using the combined injection approach, we found that increases in the dose of EN3427 with a fixed 2% lidocaine led to substantially extended analgesia and increasing doses of lidocaine combined with a fixed dose of EN3427 (0.2%) led to only modestly increased duration of action. The present studies demonstrate that a new molecular entity, EN3427, produces effective and long-lasting analgesia in 2 rodent pain models. The analgesic effects of EN3427 are significantly longer-lasting than lidocaine and are further extended when EN3427 is combined with lidocaine. The results are discussed with respect to a possible lidocaine-mediated TRP channel activation and facilitated neuronal access of EN3427, with subsequent entrapment conferring extended-duration efficacy.

Delayed urticaria caused by lidocaine in a child

Lidocaine is a commonly used local anesthetic for dental treatment. Urticaria caused by lidocaine has seldom been reported. Generally, urticaria immediately develops after exposure to a causative agent and is considered a manifestation of IgE-mediated hypersensitivity. However, delayed urticaria caused by local anesthetics was reported to be related to cell mediated hypersenstivity. A 3-year old girl visited our allergy clinic due to delayed urticaria after local administration of lidocaine. Both skin prick and intradermal tests with lidocaine revealed negative reactions. However, the provocation test with subcutaneous injection of lidocaine showed urticaria 7 hours after test. In order to identify alternative local anesthetic for the subsequent dental procedure, we performed skin prick, intradermal and provocation tests with procaine, a local anesthetic of the other class, all of which showed negative results. Therefore, we recommended procaine as an alternative local anesthetic, and the patient was successfully treated with procaine. To the best of our knowledge, this is the first case of delayed urticaria caused by lidocaine in Korea. (Allergy Asthma Respir Dis 2014;2:298-301)

High-Dose Daily Opioid Administration and Poor Functional Status Intensify Local Anesthetic Injection Pain in Cancer Patients

Background: Evidence for opioid-induced hyperalgesia (OIH) has been shown in animal and human studies, but the clinical implications of this phenomenon remain unclear. Objectives: We examined whether cancer patients taking opioids differ in their sensitivity to a clinical pain stimulus using a local anesthetic injection compared to those not taking opioids. We also evaluated the effect of the opioid dose, duration of opioid therapy, and patients’ pain severity and functional status on this clinical pain stimulus. Study Design: Prospective observational study. Setting: University outpatient department for interventional pain management, Republic of Korea. Methods: Eighty-two cancer patients including 20 patients not taking opioids (non-opioid group) and 62 taking opioids (opioid group) who were scheduled for an interventional procedure were enrolled in this study. Patients received a standardized subcutaneous injection of lidocaine prior to a full dose of local anesthetic (LA). Before the injection, patients completed the Brief Pain Inventory (BPI) questionnaire and were asked to rate their current pain using numeric rating scales. Immediately following the injection, LA injection-specific pain was evaluated using pain intensity, unpleasantness, and behavior pain scores. Results: LA injection-specific pain intensity, unpleasantness, and behavior pain score were significantly higher in the opioid group compared with the non-opioid group (P &lt; 0.001). In the opioid group, these post-injection pain scores were higher in patients taking high-dose opioids than those taking low doses (P &lt; 0.05). In addition, we observed a strong correlation between the baseline BPI pain interference score and the LA injection-specific pain score (r = 0.695, P &lt; 0.001). Limitations: This study is limited by its sample size and observational design. Various opioid medications, which were not standardized, may have inadvertently biased our results. Finally, the pain assessed by a brief stimulus does not fully reflect disturbances in endogenous pain inhibitory processes. Conclusion: The results of this study suggest that opioid medication is an important contributing factor to pain perception accompanying LA injection, and cancer patients using high-dose opioids may be highly susceptible to hyperalgesic responses to this clinical stimulus. We also suggest that the possible presence of OIH may be intensified among cancer patients with poor physical and psychosocial functional status. Key words: Adverse effects; analgesics, opioid; anesthetics, local; cancer; hyperalgesia; injections, subcutaneous; nociceptive pain; pain measurement; pain perception; quality of life

The effectiveness of superficial subcutaneous lidocaine administration prior to femoral artery sheath removal.

The dynamic world of healthcare requires continuous review of practice to ensure that patient care aligns with current evidence and best practice. Superficial subcutaneous lidocaine injection has been an order option at London Health Sciences Centre-University Hospital (LHSC-UH) for use in post-percutaneous coronary intervention (PCI) prior to femoral artery sheath removal (FASR). The purpose of administering lidocaine is to reduce pain during FASR, subsequently enhancing the patient's experience. A critical appraisal was performed by the Continuous Quality Improvement-Cardiac Care Council (CQI-CCC) at LHSC-UH, evaluating the effectiveness of superficial subcutaneous lidocaine for use in patients undergoing FASR. This paper details the process followed to evaluate this practice and reports on the subsequent findings and recommendations. A literature review, a retrospective chart audit, a blinded online survey and peer hospital polling were compiled, and a summary of findings was shared with the cardiac interventionists, with subsequent polling. No significant evidence for pain reduction was identified when lidocaine injections were administered prior to FASR. As such, a unanimous decision was reached to remove lidocaine from the LHSC Coronary Angioplasty Clinical Pathway order form.

Lidocaine/tetracaine patch (Rapydan) for topical anaesthesia before arterial access: a double-blind, randomized trial

Arterial catheterization is painful and is associated with patient stress and anxiety. Analgesia is usually provided by subcutaneous injection of local anaesthetic. An alternative is topical anaesthesia, such as Rapydan which is a novel topical anaesthetic patch containing 70 mg each of lidocaine and tetracaine. We therefore tested the hypothesis that Rapydan patch analgesia is non-inferior to subcutaneous local anaesthetic. Ninety patients undergoing elective major cardiac surgery were included in this prospective, double-blind clinical trial. Patients were randomly assigned to receive either a lidocaine/tetracaine patch, followed by subcutaneous injection 0.5 ml of normal saline solution, or placebo patch with subsequent subcutaneous injection of 0.5 ml of lidocaine 1%. Pain during arterial catheterization using 100-mm-long visual analogue scale (VAS) was the primary outcome. Other outcomes were pain during anaesthetic/saline injection and plasma tetracaine concentrations. VAS pain scores during arterial puncture were comparable in both groups and Rapydan was non-inferior to subcutaneous lidocaine. Pain scores at the time of subcutaneous injection were significantly lower (better) in patients assigned to the lidocaine/tetracaine patch than to lidocaine (P=0.001). Plasma tetracaine concentrations never exceeded the detection limit of 25 ng ml(-1) at any time in any patient. Both the lidocaine/tetracaine patch and subcutaneous injection of lidocaine provided comparable pain control during arterial catheter insertion. Subcutaneous lidocaine caused discomfort during injection, whereas the lidocaine/tetracaine patch required placement 20 min before the procedure. Given adequate time, the patch provided better overall analgesia by obviating the need for subcutaneous infiltration.

A case of coronary artery spasm caused by manipulation of the neck: heart rate variability analysis

A 66-year-old man with no history of ischemic heart disease underwent cervical lymph node dissection. General anesthesia was induced and maintained with remifentanil, along with propofol. With manipulation of the neck and a subcutaneous injection of lidocaine supplemented with adrenaline before the operation, a sudden decrease in blood pressure (BP) and elevation of the ST-T segment appeared on the monitoring electrocardiogram (ECG). Ephedrine, phenylephrine, adrenaline, and nitroglycerin were administered; however, the hypotension was sustained and the ECG abnormalities progressed, along with further elevation of the ST-T segment and a complete atrioventricular block. Following an injection of atropine, the changes in ECG and BP were attenuated. Heart rate variability (HRV) was analyzed using fully recorded monitor variables, and revealed an increase in the high-frequency domain at the time of the cervical manipulation, suggesting simultaneous vagal stimulation and coronary artery spasm. We concluded that the cervical manipulation had increased the vagal tone and we note that HRV analysis was useful to interpret this coronary event.