Anesthetic Cream Research Articles

The Use of Topical Anesthesia During Intravenous Catheter Insertion in Adults: A Comparison of Pain Scores Using LMX-4 Versus Placebo

Intravenous (IV) catheter placement is an extremely common painful procedure performed in all ages and healthcare settings, more often than not without anesthetics, despite clear research and guidelines demonstrating their effectiveness. This study examined differences in pain scores following topical anesthetic and placebo application, in a sample of healthy adult volunteers experiencing IV catheterization. During this prospective, placebo-controlled, double-blind study, 43 subjects were randomized to receive LMX-4 on one hand and hand cream on the other 30 minutes prior to IV catheterization. Paired t-tests were used to measure the difference in pain scores between hands. Pain scores were reported utilizing a visual analog scale (0-10 cm) immediately after each stick. As a control, the difficulty of the IV stick was rated on a 0-10 cm scale and recorded by the nurse who started the IV. The mean pain score and standard deviation reported for the LMX-4 hand was 3.2 (SD=2.25, range, 0-8.5 cm), while the placebo hand was 4.67 (SD=2.25, range, 0.25-10 mm). The mean paired difference between LMX-4 and placebo hands was -1.37 (95% CI; -2.2, -0.49); subjects receiving LMX-4 reported clinically as well as statistically significant pain reductions (t=-3.17, p=0.003). When adjusted for difficulty of stick, pain scores continued to remain lower in the LMX-4 hand. These findings suggest that the topical use of LMX-4 anesthetic cream is a viable option for reducing the pain associated with IV catheter insertion in adults.

Rapid cortical reorganisation and improved sensitivity of the hand following cutaneous anaesthesia of the forearm

The cortical representation of various body parts constantly changes based on the pattern of afferent nerve impulses. As peripheral nerve injury results in a cortical and subcortical reorganisation this has been suggested as one explanation for the poor clinical outcome seen after peripheral nerve repair in humans. Cutaneous anaesthesia of the forearm in healthy subjects and in patients with nerve injuries results in rapid improvement of hand sensitivity. The mechanism behind the improvement is probably based on a rapid cortical and subcortical reorganisation. The aim of this work was to study cortical changes following temporary cutaneous forearm anaesthesia. Ten healthy volunteers participated in the study. Twenty grams of a local anaesthetic cream (EMLA) was applied to the volar aspect of the right forearm. Functional magnetic resonance imaging was performed during sensory stimulation of all fingers of the right hand before and during cutaneous forearm anaesthesia. Sensitivity was also clinically assessed before and during forearm anaesthesia. A group analysis of functional magnetic resonance image data showed that, during anaesthesia, the hand area in the contralateral primary somatosensory cortex expanded cranially over the anaesthetised forearm area. Clinically right hand sensitivity in the volunteers improved during forearm anaesthesia. No significant changes were seen in the left hand. The clinically improved hand sensitivity following forearm anaesthesia is probably based on a rapid expansion of the hand area in the primary somatosensory cortex which presumably results in more nerve cells being made available for the hand in the primary somatosensory cortex.

Hair removal with the long-pulse alexandrite and long-pulse Nd:YAG lasers is safe and well tolerated in children

Children with excessive hair may have severe psychological consequences. Laser hair removal in adults is known to be safe and well tolerated, but this is less well established in children. To describe our experience with laser hair removal in children, and to investigate the safety and tolerability of this procedure in children. The case records of 24 children aged < 16 years, who had received a minimum of three treatments for hair removal were analysed retrospectively. For patients with Fitzpatrick skin phototype II-IV, the lasers used were a long-pulse alexandrite (755 nm) with either continuous chilled-air cooling at fluences of 16-27 J/cm(2) or a long-pulse alexandrite with cryogen cooling at fluences of 16-32 J/cm(2). For patients with Fitzpatrick skin phototype IV-VI, lasers used were a long-pulse Nd:YAG (1064 nm) with a chilled contact sapphire tip at fluences of 20-35 J/cm(2) or a long-pulse Nd:YAG with cryogen cooling at fluences of 16-26 J/cm(2). Mean age at first treatment was 12.3 years. Diagnoses were constitutional hirsutism (14 patients), polycystic ovarian syndrome (five), congenital melanocytic naevus (two), generalized hypertrichosis (two) and naevoid hypertrichosis (one). One patient required a general anaesthetic, eight required topical anaesthetic cream, and 15 did not require any form of anaesthesia. Intolerable discomfort requiring adjustment in fluence was the only recorded side-effect, affecting two cases. There were no incidences of blistering, infection, dyspigmentation or scarring. When administered appropriately, laser hair removal is safe and well tolerated in children aged < 16 years.

Improved sensibility of the foot after temporary cutaneous anesthesia of the lower leg

Cutaneous anesthesia (EMLA_cream) of the forearm results in rapid improvement of hand sensibility, and here we applied this concept in the lower extremity. This double-blind study with 40 volunteers randomized to cutaneous application of anesthetic cream to the lower leg showed a significant improvement 2 h after treatment in touch thresholds in the EMLA group as compared with the placebo group. In 12 volunteers, fMRI examination was performed before and after treatment. Improvement was not associated with a visible cortical expansion of the cortical foot area. This novel finding may have considerable therapeutic potential in the treatment of foot sensibility disturbances in various neuropathies, such as diabetic neuropathy.

Change of skin color after application of topical anesthetic cream

Change of skin color after application of topical anesthetic cream

Caudal epidural block versus other methods of postoperative pain relief for circumcision in boys.

Techniques to minimize the postoperative discomfort of penile surgery, such as circumcision, include caudal block; penile block; systemic opioids and topical local anaesthetic cream, emulsion or gel. To compare the effects of caudal epidural analgesia with other forms of postoperative analgesia following circumcision in boys. We searched CENTRAL (The Cochrane Library 2008, Issue 1), MEDLINE (to April 2008) and EMBASE (to April 2008). Randomized and quasi-randomized trials of postoperative analgesia by caudal epidural block compared with non-caudal analgesia in boys, aged between 28 days and 16 years, having elective surgery for circumcision. Two review authors independently carried out assessment of study eligibility, data extraction and assessment of the risk of bias in included studies. We included 10 trials involving 721 boys. No difference was seen between caudal and parenteral analgesia in the need for rescue or other analgesia (relative risk (RR) 0.41, 95% confidence interval (CI) 0.12 to 1.43; 4 trials, 235 boys; random-effects model) or on the incidence of nausea and vomiting (RR 0.61, 95% CI 0.36 to 1.05; 4 trials, 235 boys). No difference in the need for rescue or other analgesia was seen for caudal compared with dorsal nerve penile block (DNPB) (RR 1.25, 95% CI 0.64 to 2.44; 4 trials, 336 boys; random-effects model). No differences were seen between caudal block and DNPB in the incidence of nausea and vomiting (RR 1.88, 95% CI 0.70 to 5.04; 4 trials, 334 boys; random effects model) or individual complications except for motor block (RR 17.00, 95% CI 1.01 to 286.82; 1 trial, 100 boys) and motor or leg weakness (RR 10.67, 95% CI 1.32 to 86.09; 2 trials, 107 boys). These were significantly more common in the caudal block groups than with DNPB. No differences were seen between caudal and rectal or intravenous analgesia in the need for rescue analgesia or any other outcomes (2 trials, 162 boys). Differences in the need for rescue or other analgesia could not be detected between caudal, parenteral and penile block methods. In day-case surgery, penile block may be preferable to caudal block in children old enough to walk due to the possibility of temporary leg weakness after caudal block. Evidence from trials is limited by small numbers and poor methodology. There is a need for properly designed trials comparing caudal epidural block with other methods such as morphine, simple analgesics and topical local anaesthetic creams, emulsions or gels.

Evaluation of dressings used with local anaesthetic cream and for peripheral venous cannulation

To compare four polyurethane dressings manufactured by two different companies for use in children. Seventy-eight dressings were applied to secure either local anaesthetic creams (n = 62) or intravenous cannulae (n = 16). Each dressing was evaluated for ease of application, security and ease of removal, using a simple scoring system. 84 per cent of Opsite flexigrid and 90 per cent of Tegaderm local anaesthetic cream dressings were rated as easy or very easy to apply. Opsite flexigrid was felt to be more secure, whereas Tegaderm was easier to remove. The Tegaderm cannula dressing was easier to apply than the iv3000 dressing. There was little difference between the two brands, including costs.

Evaluation of dressings used with local anaesthetic cream and for peripheral venous cannulation

Evaluation of dressings used with local anaesthetic cream and for peripheral venous cannulation

Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

Can Topical Anesthetic Reduce the Pain Associated with Diagnostic Blocks of the Lumbosacral Spine?: Table 1

To evaluate the effectiveness of a topical local anesthetic cream (5% liposomal lidocaine) in reducing needle-induced pain in patients investigated for suspected zygapophysial (z-joint) or sacroiliac (SI) joint pain. Triple-blinded randomized controlled trial. Setting. Interventional fluoroscopy suite. Eighteen patients presenting with chronic mechanical low back pain. Thirty minutes prior to diagnostic z- or SI joint blocks, equivalent amounts of topical 5% liposomal lidocaine cream was applied to one side of the low back and a placebo cream to the other. The treatment side and injection order were randomized and the patient, injectionist, and data recorder were blinded. The subjects provided numerical rating scores of pain intensity immediately following each phase of the injection (skin penetration, deep, overall). Scores were analyzed with dependent t-tests. The injection associated pain was significantly less during the skin penetration phase on the side of the local anesthetic vs the placebo cream (3.0/10 vs 4.2/10; P = 0.002). No significant differences were found during the deep phase or for the injection procedure overall. Five percent liposomal lidocaine cream significantly reduces the pain associated with the skin penetration phase of lumbosacral diagnostic blocks but does not change the pain associated with the deep phase or the injection procedure overall. Its usefulness for this application is questionable.

Transient hyperaemic response to assess vascular reactivity of skin: effect of topical anaesthesia

BackgroundLocal anaesthetics affect blood vessels in various ways, depending upon the site of action and the drug used. There is controversy over the vascular effects of two widely used topical local anaesthetic agents, EMLA® and Ametop®. We used the transient hyperaemic response (THR) to the brief compression of the brachial artery to assess vascular reactivity of forearm skin after application of topical local anaesthesia. MethodsTwenty healthy male volunteers were studied. Forearm blood flow-flux was measured using laser Doppler flowmetry, and the magnitude of the hyperaemic response to brachial artery occlusion for 20 s was recorded. Control cream, EMLA®, or Ametop® were applied and covered with an occlusive dressing for 60 min. Blood flow-flux and the hyperaemic response measurements were then repeated, with the laser Doppler probes sited over the areas of skin to which the local anaesthetic creams had been applied. Measurements were made at 60, 90, and 120 min after the application of the creams. The THR ratio (THRR) was calculated at each time point, defined as the net hyperaemic flow-flux divided by the baseline flow-flux. ResultsAt 60 min, Ametop caused a significantly greater increase in blood flow and decrease in THRR over control than EMLA [net increase of mean blood flow (sd) over control 95 (61) vs 2 (17) AU (P<0.001), net mean THRR decrease over control 1.33 (1.85) vs −0.34 (1.33) (P<0.02)]. ConclusionsThe application of topical Ametop decreases microvascular tone and vasoreactivity of the forearm skin in healthy volunteers.

555: Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

555: Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

555. Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

555. Local Anaesthetic Cream (EMAL®) for Excacerbation of Pain in Trigeminal Neuralgia

Topical Anesthetic Creams

Topical anesthetic creams have positive applications in plastic surgery. For certain procedures, they can replace injected local anesthetics. By replacing injections with a topical cream, the negative effects associated with injections, such as pain, needle anxiety, and edema at the surgical site, are eliminated. A variety of U.S. Food and Drug Administration-approved topical anesthetic creams are available for use; however, much care must be taken when prescribing and administering these drugs, as anesthetic creams compounded in nonstandard doses can result in severe toxicity and death. When used appropriately, topical anesthetic creams can provide a safe and effective alternative to other forms of anesthesia. This article provides an overview of topical anesthetic creams, including availability, composition, safety, and efficacy.

Topical Anesthesia With EMLA does Not Decrease Pain During Vasectomy

Previous studies show conflicting results of the ability of EMLA (eutectic mixture of local anesthetics) to decrease pain during vasectomy. We examined the effectiveness of EMLA cream to decrease pain in patients undergoing bilateral percutaneous no-scalpel vasectomy. A prospective study was performed in which 316 patients used EMLA cream (178) or no topical anesthesia (138) before vasectomy. EMLA cream was applied by patients 1 hour before the scheduled time of surgery. Bilateral percutaneous no-scalpel vasectomy was then performed in the 2 groups with local infiltration of 1% lidocaine into the scrotal wall and vasal sheath. Following the procedure patients were asked to rate their associated pain using a visual analog scale. Statistical analysis was performed using the 2-sided Student t test. Mean patient age was similar in the groups with and without EMLA (39.1 and 39.0 years, respectively). No significant difference in mean visual analog pain scores were noted between the EMLA and control groups (21.5 vs 21.0, p = 0.8). Topical anesthesia with EMLA did not significantly decrease the pain associated with percutaneous vasectomy.

What do men with premature ejaculation prefer: daily or on-demand drug treatment?

Since the 1930s various drugs have been used to treat premature ejaculation (PE). Currently, there are two major strategies to treat PE. First, daily treatment (selective serotonin reuptake inhibitors (SSRIs), and clomipramine). Second, on-demand treatment (anesthetic creams, SSRIs, clomipramine, tramadol, PDE-5 inhibitors). According to a meta-analysis of all drug treatment studies, published between 1943 and 2003, daily treatment with 20 mg paroxetine exerts the strongest ejaculation delay, compared to other serotonergic drugs. In contrast, on-demand use of SSRIs, including the new SSRI dapoxetine, exerts only a minimal ejaculation delay. Both daily and on-demand use of SSRIs may give rise to drug-induced side effects, like nausea, fatigue and yawning. Advantages of daily SSRI treatment are 1) the disappearance of side effects after 2-3 weeks of treatment and 2) it does not interfere with the spontaneity of having sex; at each moment of the day ejaculation will be delayed. Disadvantages of on-demand treatment is the likely hood of experiencing side effects at the moment of making love and its negative interference with the spontaneity of having sex. One always has to wait 1-6 hours before ejaculation delay occurs. Despite these disadvantages, pharmaceutical companies are promoting on-demand drugs for the treatment of PE. However, until recently there have been no specific studies investigating which strategy of drug treatment is preferred by men with PE. In 2007, Waldinger et al published the first study of this kind. In this observational questionnaire survey, preferences of different treatment strategies were queried before and after standard efficacy and safety information. The population consisted of a consecutive group of 88 men with lifelong PE who decided for themselves to be seen for rapid ejaculation. The age was 37±11years (mean± SD), range 18-64 years. None of these men was ever treated for PE and 21% used medication that did not affect sexual performance. Of them, 71 (81%) preferred a drug for daily use, 14(16%) a drug on-demand, while three men preferred topical anesthetic cream. Those men who initially preferred daily treatment did not change their view after standard information about efficacy and side effects, while 9 of 17 men who initially preferred on-demand drug treatment had switched their preferences to daily oral drug usage. The most frequently reported argument to prefer daily drug treatment was that this strategy would have the least effects toward the spontaneity of having sex. It was concluded that opposed to agents which must be taken 4-6 hours prior to coitus and with the methods used, this group of Dutch men with lifelong PE favor uninterrupted daily drug treatment to delay ejaculation mainly because daily treatment guarantees no interference with the spontaneity of having sex.

Local Anesthetic Cream Prepared from Lidocaine-Tetracaine Eutectic Mixture

Local anesthetic creams for the clinical treatment of conditions such as postherpetic neuralgia were prepared as an in-house formulation from the eutectic mixture of lidocaine-tetracaine (LT cream) using two eutectic mixtures of local anesthetic (EMLA) type bases. The LT formulation was compared with a lidocaine-prilocaine (LP cream) eutectic mixture formulated using the same base as EMLA. The chemical stability of lidocaine was examined in advance and was found to be stable for more than 3 months either in LT cream or in LP cream. The release rate of lidocaine from the formulated creams was examined using a cellulose ester membrane. The release rate of lidocaine from LT cream was similar to that from LP cream. The release rate of tetracaine was slightly slower than that of lidocaine in LT cream reflecting the larger molecular size of tetracaine. The penetration rate was examined in vitro using a Yucatan micropig skin. The penetration rate of lidocaine was similar between LT and LP creams. Infiltration anesthesia action examined in guinea pigs indicated that the difference between the two creams was statistically insignificant. The present study suggests the equivalence of the LT and LP creams as a local anesthetic and the potential of LT cream for clinical use either in the easy formulation or in the low-cost formulation.

Application of Topical Analgesia in Triage: A Potential for Harm

To reduce the overall time spent in the ED, triage nurses are encouraged to treat patients with a topical anesthetic cream, eutectic mixture of local anesthetics (EMLA®). We present a case in which a 28-day-old neonate who was treated with EMLA® cream in triage developed severe methemoglobinemia 18 hours post admission to the pediatric ward. This case demonstrates that there may be some risks associated with this approach, and that protocols for the use of EMLA® at triage should include not only the indications for its use, but also need to ensure that there is a process to have the EMLA® removed before patient discharge or transfer.

Galactography without discomfort using lidocaine/prilocaine anesthetic cream

Galactography (ductography) is the technique of choice for studying pathologic nipple discharge. It is sometimes difficult or even impossible to perform cannulation of the ductal orifice because of the discomfort caused to the patient. To evaluate the efficacy of a eutectic mixture of local anesthetics (EMLA) containing lidocaine and prilocaine applied as a cream to reduce discomfort during galactography. 46 patients with abnormal nipple secretion underwent galactography. The patients were distributed in non-randomized form into two groups (A and B). Group A consisted of 19 patients who were treated without application of the anesthetic cream; group B consisted of 27 patients to whom the anesthetic cream was applied prior to galactography. Pain intensity was measured using a verbal description scale. Galactography was successfully performed in all cases in group B (n = 27) and in 15 cases (78.9%) in group A. In four patients from group A, it was initially impossible to cannulate the discharging duct because of patient discomfort and anxiety. The same patients were submitted to galactography 1 week later after application of the anesthetic cream to the areola/nipple area. In total, then, 31 cases (all 27 of group B plus four) registered 0 ( = no pain) on the verbal description scale after application of the cream. In the 19 patients of group A, the degree of pain registered was mild in 11 cases and discomforting in eight cases. The application of anesthetic cream over the areola/nipple area enables galactography to be performed without patient discomfort. It also reduces anxiety, allowing the radiologist to perform the procedure with confidence and safety, and without stress on the part of the patient or radiologist.

The effect of local anaesthetic cream (EMLA®) applied with an occlusive dressing on skin thickness. Does it matter?

The effect of local anaesthetic cream (EMLA®) applied with an occlusive dressing on skin thickness. Does it matter?