Cryoanalgesic versus EMLA® cream to reduced pain during analgesic injection in upper eyelid surgery: a randomized trial.

INTRODUCTION: Eyelid surgery under local anesthesia is a common procedure in ophthalmology. The most painful part is usually injecting local anesthesia. Decreased sensation from the very sensitive eyelid skin before injection is one of the few methods to relieve this stressful condition. In this study, we compared the use of the aesthetic property of cooling (cryoanalgesic) with topical EMLA® cream preparation before local anesthetic injection on the eyelid. METHODS: Thirty patients aged 47-81 years (mean = 65.6, SD = 9.75) undergoing upper eyelid blepharoplasty or levator advancement surgery were enrolled. Each subject's upper eyelid was randomly allocated by a computer-generated randomization sequence to an EMLA® cream or cryoanalgesic group before injecting local anesthetic. Pain monitoring was performed subjectively and objectively using a visual analog scale (VAS). Results were analyzed using the paired t-test. RESULTS: No statistical difference was found in VAS score between the EMLA® cream (mean = 5.9) and cryoanalgesic groups (mean = 5.67) (p-value 0.5999). CONCLUSION: Topical EMLA® cream and cryoanalgesic have no difference in pain score from anesthetic infiltration during eyelid surgery.

Comparison of the efficacy of two different local anesthetics in inferior turbinate reduction.

PURPOSE: The present study compares the local anesthetic efficacy of EMLA® cream and lidocaine injection used in the radiofrequency reduction of the inferior turbinate. METHODS: The study included a total of 124 patients with inferior turbinate hypertrophy and who underwent turbinate reduction under local anesthesia. The operations were performed 15 min after a lidocaine injection and 30 min after EMLA cream application. The respondent patients were asked to interpret such situations as intraoperative pain, discomfort during the procedure, choking sensation and difficulty swallowing using the Visual Analogue Scale (VAS). RESULTS: The EMLA cream patients (Group A) were found to have a lower level of discomfort, choking sensation and difficulty swallowing than the lidocaine patients (Group B), while there was no substantial difference in pain between the two groups. CONCLUSIONS: It is concluded that EMLA® cream is an effective alternative to lidocaine injection during inferior turbinate reduction procedures.

Comparison of the Effect of Massage and EMLA Cream on Children's Physiological Indices During Venipuncture: A Factorial Clinical Trial.

PURPOSE: The aim of this study was to identify the effect of massage, EMLA cream, and the combination of these two methods on changes in physiological indices because of pain caused by intravenous line insertion in preschool children. DESIGN: A four-group randomized nonblinded clinical trial with factorial design. METHODS: In total, 140 eligible 3- to 6-year-old children entered the study in Tabriz Children's Hospital in 2017 and were randomly allocated to four groups (EMLA cream, massage, combination of the two, and control). Physiological responses were measured before and immediately after interventions in all groups. Data were collected and analyzed using SPSS version 19. FINDINGS: Comparison of the physiological indices changes caused by pain between groups showed that changes in children's heart rate (HR) and respiratory rate (RR) in the EMLA group and in the combined-method group were statistically significant (P < .05). No significant differences were found in systolic blood pressure and oxygen saturation (SPo2) between the four groups. CONCLUSIONS: Results indicated that EMLA cream was more effective than massage and a combination of EMLA and massage in reducing an increase in the HR and RR caused by pain in children. Massage alone was not effective in significantly lowering the children's increased physiological indices such as the HR and RR, and it seems the effectiveness of massage is more noticeable in conjunction with EMLA cream.

Palatal needle-free anesthesia for upper molars extraction. A randomized clinical trial.

BACKGROUND: The aim of this study was to compare the ability of liposomal and non-liposomal lidocaine and prilocaine in hydrogel formulations to promote topical anesthesia in palatal mucosa during upper molar extractions. METHODS: In this randomized, cross over, triple-blinded clinical trial, a liposomal and a non-liposomal formulation of the eutectic mixture of local anesthetics, 2.5% lidocaine and 2.5% prilocaine, were used to promote palatal anesthesia without the local anesthetic infiltration during bilateral upper molars extractions. RESULTS: From the total of 40 patients included in this study, the non-liposomal eutectic lidocaine-prilocaine formulation failed in 40% of cases, unlike the liposomal formulation, which was effective for all patients (Fisher's exact test, p < 0.0001). Furthermore, the liposomal formulation (26.75 ± 7,47 min) induced longer anesthesia duration (t-test, p < 0.0001) than the non-liposomal formulation (16.78 ± 4.75 min). No mucosal ulceration or discomfort was reported for both formulations. CONCLUSION: The liposomal formulation was able to induce adequate anesthesia in palatal mucosa during dental extraction, avoiding the local anesthetic infiltration. For the first time, a topical formulation allowed upper molars surgical removal without injection of any local anesthetic agent into palatal mucosa in adults.

Acute cortisol and behavior of dairy goat kids administered local anesthesia, topical anesthesia or systemic analgesia prior to cautery disbudding.

Cautery disbudding of goat kids causes thermal burns and tissue destruction, which results in acute and post-operative pain and negatively affects animal welfare. The objectives of this study were to evaluate acute cortisol concentrations and behavioral responses associated with (1) injecting a lidocaine ring block prior to cautery disbudding and comparing this to saline injections and (2) pain mitigation strategies (lidocaine ring block, topical eutectic mixture of local anesthetics (EMLA) cream, oral meloxicam) on cautery disbudded dairy goat kids. Sixty doe kids were allocated to one of six treatments: (1) disbudding without pain relief (DB), (2) a ring block using 1% lidocaine (DBLA) 20 min before disbudding, (3) saline injection (DBSA) 20 min before disbudding, (4) oral meloxicam 60 min before disbudding (DBMEL), (5) EMLA cream rubbed into the buds 60 min before disbudding (DBEM) and (6) handled but not disbudded (HAND). Blood was sampled pre- (-20 and -5 min) and post-treatment (15 and 30 min) to assess plasma cortisol concentrations and behavior during treatment was recorded using video cameras to assess rump movements, tail shakes and vocalizations (values presented as number/treatment). DBLA and DBSA kids showed elevated cortisol above baseline 5 min pre-disbudding (after injections) (P ≤ 0.01), which was no different to cortisol 15 min post-disbudding (P > 0.05). Rump movements and tail shakes of DBLA (5.5 ± 0.8 and 6.9 ± 1.2) and DBSA kids (5.6 ± 0.8 and 7.2 ± 1.2) were no different to those of DB kids (P > 0.10). Cortisol was elevated from baseline for 30 min post-disbudding for DBEM kids and DBMEL kids (P ≤ 0.05). Rump movements, tail shakes and vocalizations of DBEM (5.7 ± 0.8, 6.3 ± 1.2 and 11.1 ± 1.6) and DBMEL kids (5.3 ± 0.8, 8.0 ± 1.2 and 9.1 ± 1.6) were no different to those of DB kids (P > 0.05). HAND kids showed no change in cortisol over time (P > 0.10) and performed fewer rump movements, tail shakes and vocalizations than all treatments (P ≤ 0.01). In conclusion, lidocaine injection using a ring block appears to cause more pain than handling alone and may not reduce pain associated with cautery disbudding; therefore, a lidocaine ring block may not be a useful pain mitigation strategy for disbudding dairy goat kids. There was no evidence that meloxicam reduced acute pain and EMLA cream may have intensified the pain associated with disbudding. Further research on efficacious pain mitigation strategies for cautery disbudding of dairy goat kids is required.

Comparison of the efficacy of eutectic mixture of local anesthetics (EMLA) and dorsal penile nerve block (DPNB) in neonatal circumcision.

BACKGROUND: Neonates feel pain. There is a concern among practitioners that pain of injecting analgesics to neonates prior to circumcision could as well be the same as the pain of the procedure. This has made many reluctant to offer effective analgesia for circumcision. If eutectic mixture of local anesthetics (EMLA) provides analgesia comparable to dorsal penile nerve block (DPNB), it will obviate needle prick and encourage analgesia use in neonatal circumcision. AIM: To determine how the analgesic efficacy of EMLA compares with that of DPNB in neonatal plastibell circumcision. METHODS: A prospective study of 110 male neonates for plastibell circumcision randomized into two groups: A and B, of 55 each, received EMLA or DPNB as analgesia prior to circumcision, respectively. The pulse rates and SpO2 were recorded with pulse oximeter pre-procedural and at four stages of the procedure (adhesiolysis, dorsal slit, tying, and excision) for each neonate. Also the modification of neonatal infant pain scale (NIPS) was recorded during the procedure. RESULTS: There were differential changes in SpO2 (lower absolute mean values) and pulse rate (higher absolute mean values) for neonates who received EMLA when compared with DPNB before the procedure. These differences were significant with SpO2 at adhesiolysis (91.0% and 95.0%), dorsal slitting (90.9% and 94.7%), and excision stages (93.4% and 95.3), respectively (P < 0.05). They were also significant with the pulse rates at adhesiolysis (167.9 and 158.6), dorsal slitting (174.3 and 161.7), and tying stages (182.2 and 169.0), respectively (P values = 0.013, 0.015, and 0.044, respectively). This shows DPNB is better than EMLA. However, the difference was not significant at the tying stage with SpO2 and at excision stage with PR (P > 0.05). CONCLUSION: EMLA produces analgesic effect. However, it does not provide effective analgesia for plastibell circumcision in neonates. DPNB provides a better analgesia than EMLA for neonatal plastibell circumcision.

The clinical efficacy of EMLA cream for intravenous catheter placement in client-owned dogs.

OBJECTIVE: To assess the reaction of client-owned dogs to intravenous (IV) catheter placement after applying a local anaesthetic (EMLA) or placebo cream for either 30 or 60 minutes. STUDY DESIGN: Prospective, randomized, blinded, placebo-controlled, clinical trial. ANIMALS: A total of 202 client-owned dogs of various breeds. METHODS: With owner consent, dogs were randomly allocated to one of four treatment groups: EMLA 60 minutes, EMLA 30 minutes, Placebo 60 minutes and Placebo 30 minutes. After the cream was applied for the allocated time, an IV catheter was placed and the behavioural reaction of the dog was scored. The reaction score was analysed using a Kruskal-Wallis test followed by Mann-Whitney U tests of the multiple pairwise comparisons, with Bonferroni correction. RESULTS: A large number of dogs, even in the placebo groups, did not react to IV catheter placement. However, the Kruskal-Wallis test showed an overall difference between treatment groups (χ2 = 11.029, df = 3, p = 0.012). The pairwise comparisons showed a lower overall reaction score in the EMLA 60 group than in the EMLA 30 and Placebo 60 groups (adjusted p = 0.018 and adjusted p = 0.044, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: This study shows that EMLA cream applied for 60 minutes reduces the behavioural reaction of dogs to IV catheter placement; therefore, this intervention can be advocated for routine use in veterinary medicine to enhance the welfare of dogs undergoing IV catheter placement.

The effect of repeated bouts of hyperaemia on sensory nerve-mediated cutaneous vasodilatation in humans.

PURPOSE: To investigate cutaneous sensory nerve contribution to hyperaemia following chronic shear stress training. METHODS: Eleven males underwent a shear stress intervention (forearm occlusion 5 s, rest 10 s) for 30 min, 5 times·week-1 for 6 weeks on one arm, the other was an untreated control. Skin blood flow was measured using laser-Doppler flowmetry, and sensory nerve function was assessed with and without blockade with EMLA cream in response to 3 levels of local heating (39, 42, and 44 °C) and post-occlusive reactive hyperaemia (PORH). RESULTS: In response to local heating, EMLA treatment significantly delayed the onset of vasodilatation (p < 0.001), time-to-peak (p < 0.001), time to 39 °C (p < 0.02), time to 42 °C (p < 0.006), but not time to 44 °C (p > 0.2). EMLA treatment also increased time-to-peak for PORH (p ≤ 0.01). In the experimental limb after 6 weeks, both onset time and time to peak were shorter in response to local heating at the untreated and EMLA-treated sites (all p < 0.001). There were no changes in time-to-peak for PORH at the untreated and EMLA-treated sites (p ≥ 0.4); however, the peak PORH response was reduced with EMLA treatment (p ≤ 0.03). The 6-week intervention increased the peak PORH at the untreated sites (p < 0.001) but not at EMLA-treated (p > 0.05) sites. Comparing the control limb before and after 6 weeks, no differences in responses occurred at either the untreated skin sites (p ≥ 0.9) or the EMLA-treated sites (p ≥ 0.9). CONCLUSIONS: Sensory nerve blockade attenuated the improvements in cutaneous vascular responses to thermal hyperaemia and PORH following chronic exposure to shear stress. These data demonstrate an important role for sensory nerve function in the initiation of vasodilatation to both PORH and thermal hyperaemia, in both the time to onset and the magnitude of vasodilatation.

Which is more effective for pain relief during fractionated carbon dioxide laser treatment: EMLA cream or forced cold air anesthesia?

BACKGROUND AND AIM: The aim of this study was to compare the effectiveness of a eutectic mixture of local anesthetic (EMLA) cream and forced cold air anesthesia (FCAA) on pain control during ablative fractionated carbon dioxide (CO2) laser treatment. METHODS: Fifteen volunteers participated in this prospective, controlled, split-face clinical study. EMLA cream was applied 60 minutes before the laser procedure on half of the face, and FCAA was performed on each subunit of the other half of the face. The laser procedure was performed on each half of the face. Patients rated their pain during the procedure using a pain scale scored from 0-10. Both doctor and nurse rated patient discomfort during the procedure using a scale scored from 0-10. The pain scores associated with both EMLA and FCAA sides of the face were compared statistically. RESULTS: Patient pain scores and discomfort scores detected by doctor and nurse were not statistically different between EMLA and FCAA. There was no statistically significant difference between males and females. CONCLUSION: Instead of using EMLA, FCAA-which can be applied in a shorter time-may be a cost-effective, simple, and safe local anesthesia method used in the ablative fractionated CO2 laser procedure.

Comparison of Emla cream and topical lidocaine tape for pain relief of V-beam laser treatment.

The authors compared the analgesic effects of two topical applications; Emla® cream (Sato Pharmaceutical Co. Ltd., Tokyo, Japan) and 60% lidocaine tape (Penles® tape; Maruho, Osaka, Japan). The authors examined 20 outpatients with capillary malformations. Emla® cream or Penles® tape was applied 1 h before laser irradiation using V-Beam. After V-Beam irradiation, pain intensity was measured using Pain Vision® (NIPRO, Osaka, Japan), while subjective pain was converted into numerical values using the VAS system. In the assessment using Pain Vision®, pain was significantly lower in patients who received Emla® cream (Welch test), whereas no difference was observed in VAS ratings between the two applications (student's t test). The objective system showed that Emla® cream had a significantly greater analgesic effect. We plan to evaluate the analgesic effects of these topical anesthetics by applying them to other anatomical areas.

Comparison of Emla cream and lidocaine injection for local anaesthetic before radiofrequency reduction of the inferior turbinates.

We compared the effectiveness of local anaesthetic with Emla cream with that of an injection of lidocaine for radiofrequency reduction of the inferior turbinates. We studied 98 consecutive patients with hypertrophied inferior turbinates, 46 of whom were given Emla cream and 52 lidocaine injection. The procedure began five minutes after the injection of lidocaine and 10minutes after the Emla cream had been applied. Patients were asked to indicate on a visual analogue scale (VAS) the degree of perioperative pain, anxiety, sensation of choking, and discomfort on swallowing that they felt after the procedure. Patients treated with Emla had significantly lower VAS scores for discomfort on swallowing than those treated with lidocaine (p=0.001), but there were no other significant differences between the two groups. We conclude that Emla cream is an efficacious alternative to infiltration of lidocaine for radiofrequency reduction of the inferior turbinates.

Topic anaesthesia with a eutectic mixture of lidocaine/prilocaine cream after elective caesarean section: a randomised, placebo-controlled trial.

PURPOSE: Aim of the study was to investigate the topical application of a eutectic mixture of lidocaine/prilocaine (EMLA®) cream after caesarean section (CS) and its effect on postoperative pain, time to mobilisation, and time to discharge. MATERIALS AND METHODS: A total of 189 pregnant women were enrolled; full data sets were available for 139 of them, who were prospectively randomised to receive either placebo (control group) or EMLA® cream (study group) on the CS lesion directly as well as 24 h after surgery. Postoperative pain was assessed 24 and 48 h after surgery using the short form of the McGill Pain Questionnaire (SF-MPQ). Additional analgesic pain medication on demand was assessed in both groups. RESULTS: A total of 62 women were allocated randomly to the study and 77 patients to the control group before primary CS. There were no statistically significant differences regarding demographic and surgical parameters comparing both collectives. In addition, the postoperative total pain scores after 24 h [McGill total: 38.5 (0-102) vs. 50 (0-120) p = 0.0889] as well as after 48 h [24 (0-79) vs. 30.5 (0-92); p = 0.1455] showed no significant differences. Furthermore, time to mobilisation (hours) [9.68 (2.18-51.38) vs. 9.47 (4.18-41.77); p = 0.5919] and time to discharge (hours) [98.6 (54.08-170.15) vs. 98.2 (43.45-195.87); p = 0.5331] were comparable. CONCLUSION: The postoperative application of EMLA® cream after CS did not reduce postoperative pain or time to mobilisation or discharge, so that its use in this context has to be seen critically.

In vitro and in vivo Evaluation of New Topical Anaesthetic Cream Formulated with Palm Oil Base.

BACKGROUND: Topical local anaesthetic cream was reported to be useful for pain relief for cutaneous procedures such as minor surgery and venipuncture. OBJECTIVE: The aim of this study was to evaluate the effectiveness of new formulation of lidocaine topical anaesthetic using palm oil base, HAMIN® and to determine how fast this new formulation produces adequate numbness compared to the currently used EMLA cream, in the University of Malaya Medical Centre (UMMC) set-up. METHOD: The skin permeation test was conducted by using Franz type diffusion cell and pain assessment was carried out in healthy subject by using Verbal Rating Score (VRS) and Visual Analogue Score (VAS) evaluation. RESULT: Result of permeation test demonstrated that the cumulative amount of lidocaine released from HAMIN® cream was increased with time and slightly higher than EMLA cream. The clinical study showed that HAMIN® single lidocaine cream can produces numbness through venepuncture procedure and comparable with EMLA cream which is a combination therapy for local anaesthetic (lidocaine and prilocaine). CONCLUSION: It can be concluded that HAMIN® Lidocaine cream is suitable for cream preparation especially for topical application and it can be regarded as an achievement in palm oil and medical industries.

Effect of Topical Anesthesia with Lidocaine-prilocaine (EMLA) Cream and Local Pressure on Pain during Infiltration Injection for Maxillary Canines: A Randomized Double-blind clinical trial.

OBJECTIVES: This study compared the effect of local pressure and topical lidocaine-prilocaine (EMLA) cream on pain during infiltration injection for maxillary canine teeth. MATERIALS AND METHODS: A total of 140 volunteer students participated in this split-mouth design randomized clinical trial. The subjects were randomly divided into four groups (n = 35). Before administration of anesthesia, in each group, one side was randomly selected as the experimental and the opposite side as the control. In group 1, finger pressure was applied on the alveolar mucosa on the experimental side and on the tooth crown on the control side. In group 2, 5% EMLA cream and placebo; in group 3, finger pressure and 5% EMLA cream; and in group 4, 5% EMLA cream and 20% benzocaine gel were applied. In all the groups, a buccal infiltration procedure was carried out. Pain during injection was recorded with visual analog scale (VAS). Wilcoxon and McNemar tests were used for statistical analysis of the results. Statistical significance was set at p < 0.05. RESULTS: The results showed that EMLA reduced the injection pain significantly more than benzocaine (p = 0.02). Also, injection pain was significantly lower with the use of EMLA in comparison to placebo (p = 0.00). Application of local pressure reduced the injection pain, but the difference from the control side was not significant (p = 0.05). Furthermore, the difference between application of local pressure and EMLA was not statistically significant (p = 0.08). CONCLUSION: Topical anesthesia of 5% EMLA was more effective than 20% benzocaine in reducing pain severity during infiltration injection. However, it was not significantly different in comparison to the application of local pressure.

New insights into eutectic cream skin penetration enhancement.

The manner in which the eutectic cream EMLA enhances the percutaneous penetration of lidocaine and prilocaine into human skin is still not fully understood. The purpose of this study was to investigate if the modification of drug aggregation played a role in the way EMLA facilitates delivery. Light scattering analysis of lidocaine alone in water gave a critical aggregation concentration (CAC) of 572 µM and a mean aggregate size of 58.8 nm. The analysis of prilocaine in identical conditions gave a CAC of 1177 µM and a mean aggregate size of 105.7 ± 24.8 nm. When the two drugs were mixed at their eutectic 1:1 ratio in water the CAC reduced to 165.8 µM and the aggregate size was 43.82 nm. This lidocaine-prilocaine interaction in water was further modified upon addition of polyoxyethylene hydrogenated castor oil, the surfactant in the EMLA aqueous phase, to produce aggregates of <20 nm. The physical characterisation data suggested that it was the EMLA cream's surfactant that modified the drug molecular interactions in the aqueous continuous phase and caused a 6 fold higher drug penetration through human epidermal tissue compared to the oil formulations tested in this study.

The effect of medical clowning on reducing pain, crying, and anxiety in children aged 2-10 years old undergoing venous blood drawing--a randomized controlled study.

UNLABELLED: Recently, the utilization of medical clowns to reduce anxiety, stress, and even pain associated with hospitalization has become popular. However, the scientific basis of this benefit and outcome is scant. Venipuncture and IV cannulation are very common sources of pain in ill children. To reduce pain, one common approach is to apply a local anesthetic prior to the procedure. In the current study, we sought to compare the utilization of medical clowning in this process with two control groups: (1) local anesthetic cream (EMLA®, Astrazeneca, London, UK) applied prior to the procedure (active control) and (2) the procedure performed with neither clown nor EMLA (control group). We hypothesized that a medical clown will reduce pain, crying, and anxiety in children undergoing this procedure.Children aged 2-10 years who required either venous blood sampling or intravenous cannulation were recruited and randomly assigned to one of the three groups. Outcome measures consisted of the duration of the whole procedure (measured objectively by an independent observer), the duration of crying (measured objectively by an independent observer), subjective assessment of pain level (a commonly used validated scale), and anxiety level regarding future blood exams (by questionnaire). Analysis of variance (ANOVA) was used to compare between the groups. p < 0.05 was considered statistically significant.One hundred children participated. Mean age was 5.3 ± 2.5 years (range 2-10 years). The duration of crying was significantly lower with clown than in the control group (1.3 ± 2.0 vs 3.8 ± 5.4 min, p = 0.01). With EMLA, this duration was 2.4 ± 2.9 min. The pain magnitude as assessed by the child was significantly lower with EMLA than in the control group (2.9 ± 3.3 vs 5.3 ± 3.8, p = 0.04), while with clown it was 4.1 ± 3.5, not significant when compared with the other two modalities. Hence, duration of crying was shortest with clown while pain assessment was lowest with EMLA. Furthermore, with clown duration of cry was significantly shorter than in controls, but pain perception did not significantly differ between these groups. As expected, the duration of the entire process was shortest in the control group (5.0 ± 3.8 min), moderate with clown (19.3 ± 5.8 min), and longest with EMLA (63.2 ± 11.4 min, p < 0.0001 between all). Parental reporting of a beneficial effect was greater with clown than with EMLA (3.6 ± 0.8 vs 3.0 ± 1.1, p = 0.02). Parental assessment of child's anxiety related to future blood tests as evaluated by telephone the following day revealed that it was significantly lower with clown than in the control group or EMLA (2.6 ± 1.2 vs 3.7 ± 1.3 or 3.8 ± 1.6, p < 0.01 for both). CONCLUSIONS: Distraction by a medical clown is helpful in children undergoing blood tests or line insertion. Although pain reduction was better with EMLA, both duration of cry and anxiety were lower with a medical clown. These results strongly encourage and support the utilization of medical clowns while drawing blood in children.

The contribution of sensory nerves to the onset threshold for cutaneous vasodilatation during gradual local skin heating of the forearm and leg.

During local skin heating, the temporal onset of vasodilatation is delayed in the leg compared to the forearm, and sensory nerve blockade abolishes these differences. However, previous work using rapid skin heating did not allow for determination of sensory nerve influences on temperature thresholds for vasodilatation. Two sites were examined on both the forearm and leg, one control (CTRL), and one treated for sensory nerve blockade (EMLA). Skin blood flux was monitored using laser-Doppler probes, with heaters controlling local skin temperature (Tloc). Tloc was increased from 32-44 °C (+1 °C·10 min(-1)). Stimulus-response curves were constructed by fitting a four-parameter logistic function. EMLA significantly increased Tloc onset in the forearm (CTRL=35.3 ± 0.4 °C; EMLA=36.8 ± 0.7 °C) and leg (CTRL=36.5 ± 0.4 °C; EMLA=38.4 ± 0.5 °C; both P<0.05). At both CTRL and EMLA, Tloc onset was higher in the leg compared to the forearm (both P<0.05). In the forearm, median effective temperature to elicit 50% vasodilatation (ET50) was similar between sites (CTRL=39.7 ± 0.3 °C; EMLA=40.2 ± 0.4 °C; P=0.09); however, in the leg, EMLA significantly increased ET50 (CTRL=40.2 ± 0.3 °C; EMLA=41.0 ± 0.3 °C)(P<0.05). At CTRL sites, no limb difference was observed for ET50 (P=0.06); however, with EMLA, ET50 was significantly higher in the leg (P<0.05). EMLA significantly increased the gain of the slope at the forearm, (CTRL=0.31 ± 0.01%CVCmax·°C(-1); EMLA=0.45 ± 0.07%CVCmax·°C(-1)), and leg (CTRL=0.37 ± 0.05%CVCmax·°C(-1); EMLA=0.54 ± 0.04%CVCmax·°C(-1))(both P<0.05). At CTRL sites, the gain was significantly higher in the leg (P<0.05); however, for EMLA, no significant limb difference existed (P=0.10). These data indicate that the onset of vasodilatation occurs at a lower temperature in the forearm than the legs, and sensory nerves play an important role in both limbs.

Recent advances in topical anesthesia

Topical anesthetics act on the peripheral nerves and reduce the sensation of pain at the site of application. In dentistry, they are used to control local pain caused by needling, placement of orthodontic bands, the vomiting reflex, oral mucositis, and rubber-dam clamp placement. Traditional topical anesthetics contain lidocaine or benzocaine as active ingredients and are used in the form of solutions, creams, gels, and sprays. Eutectic mixtures of local anesthesia cream, a mixture of various topical anesthetics, has been reported to be more potent than other anesthetics. Recently, new products with modified ingredients and application methods have been introduced into the market. These products may be used for mild pain during periodontal treatment, such as scaling. Dentists should be aware that topical anesthetics, although rare, might induce allergic reactions or side effects as a result of an overdose. Topical anesthetics are useful aids during dental treatment, as they reduce dental phobia, especially in children, by mitigating discomfort and pain.

The Effects of EMLA on Pain Associated with Retrobulbar Injection

A prospective study was undertaken to assess the efficacy of the anesthetic cream EMLA (Eutectic Mixture of Local Anesthetics)in alleviating the pain of retrobulbar injection in patients undergoing cataract surgery.One-hundred forty-three patients who had undergone cataract surgery under local anesthesia in Korea Veterans Hospital from July 1999 to February 2000 were selected randomly into three groups and each of them had no significant difference in their age, sex and underlying conditions.Fifty-seven patients received the EMLA cream, 43 patients received the placebo and the remaining 43 patients received nothing.Among three groups, the EMLA group and the placebo group were double masked.The pain assessed subjectively by the patient was expressed in 11 scales (0-10).And the reactions of the patients to needle insertion, which had been objectively assessed by the one operator, were graded into 4 scales (0-3).No patient experienced serious side effects in each treatment group.In subjective grading, the EMLA group which had been graded as 2.91 +/-1.93 was proven to be more effective in reducing pain than the placebo group (6.2 +/-2.02)and the not-treated group (6.56 +/-1.64).In objective grading, the EMLA group (0.44 +/-0.63)was superior to the placebo group (0.98+/-0.99)and the no treated group (1.4 +/-0.13).In conclusion, local pretreatment using the EMLA cream to alleviate the pain on retrobulbar injection is one of good methods for enhancing the patient cooperation in cataract surgery with reduced anxiety.