Topical ketamine as a local anesthetic agent in reducing venipuncture pain: A randomized controlled trial.

AIM: Pain control is an important aspect of ED patient management, and there are many different protocols used around the world influenced by both availability of local resources as well as staff competency and experience. This study aims to evaluate the use of topical ketamine in acute pain reduction by directly comparing it to lidocaine-prilocaine (EMLA) cream. MATERIALS AND METHODS: In this randomized clinical trial, 300 adult patients classified as level 4 or 5 by ESI triage system were enrolled. These patients were divided randomly into three groups. The site of venipuncture was covered with 2 g of topical ketamine cream 10% in group one, 2 g of 5% EMLA cream in group two, and finally, in group 3 (control group), was covered with placebo (2 g of cold cream). The primary end point of the study was reported pain severity with secondary end points being onset of local anesthesia as well as any side effects noted. RESULTS: The data gathered showed pain score during venipuncture in both intervention groups were significantly lower when compared to the control group (P < 0.05). However, pain score did not differ between the 2 intervention groups (P = 0.395). There was no statistically significant difference between the ketamine or EMLA in onset of local anesthesia (P = 0.419). We noted itching and irritation was significantly higher in the EMLA group when compared to ketamine(P < 0.05). CONCLUSION: This study showed that local cutaneous ketamine is as effective as EMLA in relieving pain during venipuncture.

Effect of Local Anesthesia on Pain During Arterial Puncture: The GAEL Randomized Placebo-Controlled Trial.

BACKGROUND: Arterial puncture is often painful for patients. The aim of this study was to compare use of local anesthesia as a eutectic mixture of 2 local anesthetics, lidocaine and prilocaine, versus placebo. METHODS: We conducted a double-blind, randomized controlled trial. Subjects were eligible if arterial puncture was indicated. The primary outcome was an experienced pain > 2 on a numerical pain rating scale. As having had a previous experience of arterial puncture was expected to be predictive of the current response, we planned 3 comparisons between use of local anesthesia and placebo: in the whole sample, among subjects with a painful previous experience, and among subjects with a painless previous experience. Multiple testing was analyzed using the Bonferroni correction for the primary outcome. The secondary outcome was the numerical pain rating scale score itself. All analyses were performed on an intention-to-treat basis. RESULTS: A total of 136 subjects were included in this study. The primary outcome occurred in 20.9% in the active arm versus 37.7% in the placebo arm in the whole sample (relative risk 0.55; 95% CI when adjusting for multiple testing ranged was 0.28-1.09, P = .10; 95% CI without adjustment was 0.32-0.97, P = .038). No significant heterogeneity in the study treatment effect was found when considering previous painful or painless arterial puncture (P = .70). The numerical pain rating scale score was 1.55 ± 2.03 in active group versus 2.09 ± 2.15 in the placebo group (P = .13). CONCLUSIONS: We found that application of a eutectic mixture reduced the number of painful arterial punctures by 50% compared with placebo. However, this result was not statistically significant. (ClinicalTrials.gov registration NCT01964248.).

Effects of Valsalva Maneuver, EMLA Cream, and Stress Ball for Pregnant Women's Venipuncture Pain.

CONTEXT: Peripheral intravenous catheter (PIVC) practice is a common invasive procedure used in the diagnosis and treatment of pregnant women admitted to the hospital. Difficulties experienced during PIVC application are among the most common problems encountered in a medical facility. OBJECTIVE: The study intended to evaluate the effects of the Valsalva maneuver, the application of eutectic mixture of local anesthetics (EMLA) cream, and use of a stress ball in controlling the pain and discomfort that developed due to PIVC administration for pregnant women. DESIGN: The research team designed the study as a randomized, controlled, single-blind trial. SETTING: The research took place at the obstetrics clinic at the Practice and Research Hospital at Yozgat Bozok University in Yozgat, Turkey, between January 2019 and February 2020. PARTICIPANTS: Participants were 120 pregnant women who visited the obstetrics clinic and were admitted to the maternity ward of the hospital during that time. INTERVENTION: Participants were divided into four groups of 30 women each: (1) the Valsalva maneuver group, (2) the EMLA group, receiving an application of the cream, and (3) the stress-ball group, and (4) the control group. OUTCOME MEASURES: Data were collected through the use of a pregnancy information form and a visual analog scale. In the assessment of the data, variance analysis was used with the Kruskal Wallis and Dunn test. RESULTS: Only the pain scores of the Valsalva maneuver group were found to be significantly lower than those of the control group, whereas the pain scores of the EMLA and stress-ball groups were similar to those of the control group. CONCLUSIONS: The current study can generate awareness in pregnant women in terms of choosing between pharmacological and nonpharmacological practices that nurses use during PIVC insertion. As the only randomized controlled blind study that has been performed on the topic, the current study offers nurses evidence of a way to reduce PIVC pain in pregnant women.

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.

Eutectic mixture of local anaesthetics for pain reduction during extracorporeal shockwave lithotripsy: A systematic review and meta-analysis.

A systematic review and meta-analysis was conducted to explore the effect of a eutectic mixture of local anaesthetics (EMLA) on pain reduction during extracorporeal shockwave lithotripsy (ESWL). PubMed, Web of Science, Embase, EBSCO, and Cochrane library databases (updated March 2020) were searched for randomised controlled trials (RCTs) assessing the effect of EMLA for patients that underwent ESWL. The search strategy and study selection process were managed according to the PRISMA statement. Six RCTs were included in the meta-analysis. Overall, the results indicated that EMLA significantly reduced pain compared to the control group (RR = -2.98, 95% CI = -5.82 to -0.13, P = 0.04) with a heterogeneity of I2 = 57% (P = 0.04). Subgroup analysis showed that EMLA did not significantly reduce pain when the patients took an analgesic premedication (RR = -1.46, 95% CI = -5.89 to 2.98, P = 0.52) with a heterogeneity of I2 = 38% (P = 0.52). Conversely, studies without premedication showed a significant pain relief effect (RR = -4.08, 95% CI = -7.36 to -0.65, P = -0.80) with a heterogeneity of I2 = 48% (P = 0.14). Most studies showed there was no difference in the patient's need for analgesics. EMLA was effective for reducing pain during EWSL. However, this analgesic effect was limited and did not reduce the need for analgesics.

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.

Influence of Topical Anesthesia on Superficial Sensitivity: A Double-Blind, Randomized, Placebo-Controlled Study on 48 Healthy Subjects.

BACKGROUND: Topical anesthetics are used in noninvasive transdermal anesthesia to decrease the superficial pain sensation threshold during dermatologic surgery. Combined pain relief and sensitivity loss can avoid discomfort during the surgery. OBJECTIVE: The aim of this placebo-controlled study was to compare the efficacy of 3 commonly used topical agents by collating loss of sensitivity over time. MATERIALS AND METHODS: Three topical anesthetic creams, a topical anti-inflammatory cream, and a moisturizing cream were applied on the left volar forearm of each of the 48 healthy Caucasian participants. Sensitivity was assessed with the dynamic 2-point discrimination and the Semmes-Weinstein test at 0, 60, 90, 120, 150, and 180 minutes after cream application. RESULTS: After 180 minutes, benzocaine showed a significantly lower 2-point discrimination reduction than lidocaine alone and a lidocaine and prilocaine mixture. Sensory threshold measurements by the Semmes-Weinstein test after 60 minutes revealed a significantly higher effect with lidocaine alone and with the lidocaine and prilocaine mixture than with benzocaine. CONCLUSION: The authors found a stronger skin sensitivity reduction by the eutectic lidocaine and prilocaine mixture and lidocaine alone compared with benzocaine. We suggest increased discomfort reduction in topical anesthetic supported dermatologic surgery by the eutectic mixture and lidocaine alone.

Hybrid nanofilms as topical anesthetics for pain-free procedures in dentistry.

Topical anesthetics are widely applied in order to relieve the discomfort and anxiety caused by needle insertion and other painful superficial interventions at the oral cavity. So far, there are no commercially available effective topical anesthetic formulations for that purpose, and the most of developments are related to hydrophilic and low mucoadhesive forms. Therefore, we have prepared different hybrid nanofilms composed of biopolymer matrices (chitosan, pectin, and chitosan-pectin) blended with nanostructured lipid carriers (NLC) loading the eutectic mixture of 5% lidocaine-prilocaine (LDC-PLC), in order to fulfill this gap in the market. These dual systems were processed as hybrid nanofilms by the solvent/casting method, and its mucoadhesive, structural and mechanical properties were detailed. The most appropriate hybrid nanofilm combined the advantages of both pectin (PCT) and NLC components. The resultant material presented sustained LDC-PLC release profile for more than 8 h; permeation across porcine buccal mucosa almost twice higher than control and non-cytotoxicity against 3T3 and HACAT cell lines. Then, the in vivo efficacy of PCT/NLC formulation was compared to biopolymer film and commercial drug, exhibiting the longest-lasting anesthetic effect (> 7 h), assessed by tail flick test in mice. These pectin-based hybrid nanofilms open perspectives for clinical trials and applications beyond Dentistry.

Efficacy of Eutectic Mixture of Local Anesthetics on Pain Control During Extracorporeal Shock Wave Lithotripsy: A Systematic Review and Meta-Analysis.

BACKGROUND The efficacy of a eutectic mixture of local anesthetics (EMLA) for pain control in extracorporeal shock wave lithotripsy is unclear. The aim of this study was to assess the effect of EMLA cream on pain control during extracorporeal shock wave lithotripsy. MATERIAL AND METHODS We searched Medline, EMBASE, and the Cochrane Central Register of Controlled Trials to identify relevant randomized controlled trials that compared the pain control efficacies of EMLA vs. placebo. Study eligibility criteria, participants, and interventions: Randomized controlled trials that compared the effect of EMLA with placebo cream for patients underwent extracorporeal shock wave lithotripsy. Study appraisal and synthesis methods: Two review authors extracted data independently using a designed data extraction form and risk of bias by Cochrane Collaboration's tool. RESULTS Nine studies, including 10 randomized controlled trials with 1167 patients, were eligible. The EMLA group experienced less pain (mean difference, -0.47; 95% confidence interval, -0.78 to -0.16; p=0.003) and shorter duration of lithotripsy (mean difference, -1.70, 95% confidence interval: -2.31 to -1.10, p<0.0001) than the placebo group. There were no significant differences in the number of patients who needed extra intravenous medication (p=0.610), number of patients with insufficient extracorporeal shock wave lithotripsy pain control (p=0.530), and number of patients with opioid adverse effects (p=0.320). Limitations: Long interval between the studies, different kinds of lithotripters. CONCLUSIONS EMLA can reduce pain during the ESWL procedure.

Lidocaine-prilocaine cream versus local infiltration anesthesia in pain relief during repair of perineal trauma after vaginal delivery: a systematic review and meta-analysis.

Background: Perineal trauma is a common problem that may affect women during vaginal delivery; this trauma can be either spontaneous (tear) or intentional (episiotomy). When repair of perineal trauma is required, adequate analgesics must be obtained. Topical products as lidocaine-prilocaine (EMLA) cream is one of the suggested methods, but still there is lack of evidence with regard to its efficacy and safety.Objective: The aim of this review is to assess the evidence of utilizing EMLA cream in comparison to local perineal infiltration anesthesia for pain control during perineal repair after vaginal delivery.Data sources: Medline, Embase, Dynamed Plus, ScienceDirect, TRIP database, ClinicalTrials.gov and the Cochrane Library were searched electronically from January 2006 to May 2018 for studies investigating the effect of lidocaine-prilocaine cream in relieving pain during repair of perineal trauma.Methods of study selection: All randomized controlled trials assessing effect of lidocaine-prilocaine cream versus local infiltration anesthesia in relieving pain during repair of perineal trauma were considered for this meta-analysis. Fifteen studies were identified of which four studies deemed eligible for this review. Quality and risk of bias assessment was performed for all studies.Data extraction: Two researchers independently extracted the data from the individual articles and entered into RevMan software. The weighted mean difference (WMD) and 95% confidence interval (CI) was calculated. Statistical heterogeneity between studies was assessed by the Higgins chi-square and (I2) statistics. When heterogeneity was significant, a random-effects model was used for meta-analysis. Otherwise, the fixed effect meta-analysis was used when there was no significant heterogeneity.Results: Pooled analysis of result in "pain score" was insignificant between the two groups (WMD -1.11; 95% CI (-2.55 to 0.33); p = .13). Furthermore, the use of additional analgesia showed no statistically significant difference between the two groups (WMD 1.34; 95% CI (0.66-2.71), p = .42). Regarding patient satisfaction, an overall analysis of three studies showed significant results favoring EMLA cream group users (WMD 4.65; 95% CI (1.96-11.03), p = .0005). The pooled analysis of the outcome "duration of repair" showed the significantly shorter duration of repair in EMLA cream users (n = 92) than local infiltration anesthesia (n = 95) (1.72 min; 95% CI (-2.76 to -0.67), p = .001).Conclusions: This meta-analysis suggests that topical lidocaine-prilocaine cream gives comparable results in reducing pain during perineal repair after vaginal delivery.

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.

Local dermal application of a compound lidocaine cream in pain management of cancer wounds.

The aim of this study was to explore the analgesic effect of local application of compound lidocaine/prilocaine cream on cancer wounds during wound care in order to reduce the amount of morphine intake or completely replace the systemic morphine administration and optimize the protocol for cancer wound pain management. All patients were enrolled with a visual analog scale (VAS) pain score ≥4. Before wound care, 60 patients were randomly divided into 2 groups of 30 each: morphine group (10 mg tablet); topical 5% compound lidocaine cream group (0.2 g/cm2). VAS scores, heart rate, and Kolcaba comfort level were recorded for the two groups 10 min before and 10, 15, 20, and 25 min after wound care and data were analyzed statistically. The means for the pain score and heart rate of the topical lidocaine/prilocaine cream group were lower than those of the morphine group (P<0.01) and the Kolcaba comfort level was higher (P<0.01). Local dermal application of the compound lidocaine cream can be used as an alternative to the systemic morphine administration in cancer wound care for its safety and effectiveness. In addition, it can improve the patients' comfort and quality of life.

Comparing the effects of cold compress and Xyla-p cream on hemodynamic changes in hemodialysis patients during venipuncture.

Background The vital signs reflect the physiological state of patients in various clinical conditions. The purpose of this study was to compare the effects of cold compress and Xyla-P cream on hemodynamical changes during venipuncture in hemodialysis patients. Methods and Material In this clinical trial study, 50 patients under hemodialysis were selected by simple random sampling. The patients were then randomly assigned to either Xyla-P cream, cold compress or placebo groups. The vital signs (blood pressure and pulse) were measured upon two intermittent hemodialysis sessions before and after venipuncture. Data were analyzed using repeated measures analysis of variance. Results The mean alternation in systolic blood pressure was significantly different comparing the placebo and cold compress groups before and after intervention (p<0.001). However, the difference was not significant between the Xyla-P cream group and either placebo (p=0.402) or ice compress (p=0.698) groups. The difference of the mean diastolic blood pressure was significant comparing the placebo group with either the Xyla-P cream group (p=0.003) or cold compress group (p<0.001) before and after intervention. In addition, there was a significant difference in the mean number of heartbeats comparing the control group with either the Xyla-P cream group (p<0.001) or cold compress group (p<0.001) before and after the intervention. Conclusions Considering the beneficial effects of ice compress and the Xyla-P cream on reduction of cardiovascular parameters, it is recommended to use these methods in hemodialysis patients during venipuncture.

Acute pain responses in dairy calves undergoing cornual nerve blocks with or without topical anesthetic.

Dairy calves are routinely administered medicines, vaccines, and anesthesia via injection. Although injections are painful, little is known about methods to alleviate this pain. The aim of this study was to determine whether lidocaine-prilocaine cream, a topical anesthetic, reduced calves' pain response to a subcutaneous injection around the cornual nerve. Calves were assigned 1 of 2 treatments: lidocaine-prilocaine cream at the sites of injection (n = 10) or no cream (n = 9). Thirty minutes after treatment, calves received a subcutaneous injection of 2% buffered lidocaine hydrochloride around the left and right cornual nerves. Contrary to our hypothesis, calves that received anesthetic cream beforehand displayed more escape behaviors during the injections than control calves. Both treatments had similarly low amounts of head-related behaviors afterward. Maximum eye temperature did not differ between the calves that received anesthetic cream and control calves, although eye temperature increased over time for both treatments. Heart rate increased during the 30 s following the first injection in both treatments. There were no treatment differences for any heart rate measures over the 5-min period after the first injection (mean heart rate, root mean square of successive differences, high-frequency power, and the ratio of low-frequency power to high-frequency power). These results suggest that cornual nerve blocks with buffered lidocaine are painful and that a lidocaine-prilocaine cream was not only ineffective in reducing this pain but that it may also worsen it.

Analgesic effect of trigger point injection and EMLA for shoulder pain in patients undergoing total laparoscopic hysterectomy: A randomized controlled study.

BACKGROUD: The purpose of this study was to evaluate the effects of trigger point injection (TPI) and eutectic mixture local anesthetics (EMLA) cream on the postoperative shoulder pain in patients undergoing total laparoscopic hysterectomy. METHODS: In this randomized, single-blinded, and controlled study, total 75 patients were randomly allocated to TPI group (n = 25), EMLA group (n = 25), and control group (n = 25). TPI group received TPIs with 2 mL of 0.2% ropivacaine, and EMLA group received an occlusive dressing with EMLA cream 2 g on both shoulders. Overall, abdominal, and shoulder pains were evaluated at rest and in motion on postoperative day 3. RESULTS: The incidence of shoulder pain was significantly reduced in EMLA group (56%) compared to control (88%) or TPI (88%) groups (P = .025 in both); the severity of shoulder pain was mitigated in EMLA and TPI groups compared to control group (P < .001, each). Consequently, the overall pain decreased in EMLA group and TPI group (P = .023). The patients with exercise habit (n = 31) showed lower incidence of pain than patients without exercise habit (n = 26) (P = .002, P = .005, and P = .037 in overall, abdominal, and shoulder pain, respectively). TPI or EMLA treatments decreased shoulder pain irrespective of exercise habit (P = .001 and P < .001, respectively), but decreased overall pain only in patients without exercise habit (P = .019). Lastly, EMLA lowered overall pain score at the time of first analgesic request in ward compared to control group (P = .02). CONCLUSIONS: TPI and EMLA with occlusive dressing effectively reduced the shoulder pain after total laparoscopic hysterectomy.

Local dermal application of a compound lidocaine cream in pain management of cancer wounds

The aim of this study was to explore the analgesic effect of local application of compound lidocaine/prilocaine cream on cancer wounds during wound care in order to reduce the amount of morphine intake or completely replace the systemic morphine administration and optimize the protocol for cancer wound pain management. All patients were enrolled with a visual analog scale (VAS) pain score ≥4. Before wound care, 60 patients were randomly divided into 2 groups of 30 each: morphine group (10 mg tablet); topical 5% compound lidocaine cream group (0.2 g/cm2). VAS scores, heart rate, and Kolcaba comfort level were recorded for the two groups 10 min before and 10, 15, 20, and 25 min after wound care and data were analyzed statistically. The means for the pain score and heart rate of the topical lidocaine/prilocaine cream group were lower than those of the morphine group (P<0.01) and the Kolcaba comfort level was higher (P<0.01). Local dermal application of the compound lidocaine cream can be used as an alternative to the systemic morphine administration in cancer wound care for its safety and effectiveness. In addition, it can improve the patients' comfort and quality of life.

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.