Lidocaine/prilocaine cream (EMLA(R)) versus infiltration anaesthesia: a comparison of the analgesic efficacy for punch biopsy and electrocoagulation of genital warts in men. (33/141)

OBJECTIVES: To compare analgesic efficacy and pain caused by administration of lidocaine/prilocaine cream (EMLA(R)) versus xylocaine 1% local infiltration for punch biopsy and electrocoagulation of genital warts in men. DESIGN: Open randomised comparative parallel-group study. SETTING: Department of Dermatovenereology, University Hospital Rotterdam/Dijkzigt, the Netherlands. PATIENTS: 63 males with warts on the genital mucosa and/or perianal area. METHODS: EMLA(R) cream (2.5-5 g) was applied during 13-45 minutes before surgery. Xylocaine 1% (0.1-4 ml) was infiltrated 0.5-4 minutes before surgery. Pain during administration and surgery was assessed by the patient on a verbal rating scale and on a visual analogue scale. RESULTS: EMLA(R) application was painless in all patients (n = 31) whereas xylocaine infiltration was slightly painful in 17/29 patients and moderately painful in 10/29 patients. EMLA(R) analgesia was satisfactory for 94% of biopsies and 62% of electrocoagulations. Xylocaine infiltration was satisfactory in all procedures. CONCLUSIONS: EMLA(R) application on the male genital mucosa is painless but it has a lower analgesic efficacy than xylocaine infiltration. However EMLA is a useful anaesthetic for taking biopsies in this area and may be used as premedication for local infiltration.  (+info)

Nitrous oxide inhalation is a safe and effective way to facilitate procedures in paediatric outpatient departments. (34/141)

AIMS: To evaluate the efficacy and safety of nitrous oxide treatment given to children presenting procedural problems in a paediatric outpatient department. METHODS: The study comprised 70 children 6-18 years old. Two different groups were studied. (1) Children presenting with problems in establishing venous cannulation (VC) (n = 50). The patients were randomised to conventional treatment (CO); cutaneous application of EMLA or nitrous oxide treatment (NO); N2O and EMLA. (2) Anxious children/children undergoing painful procedures who repeatedly come to the clinic (n = 20). These children underwent two procedures with CO/NO, the order of priority being randomised. Altogether the study included 90 procedures. Main outcome measures were procedure time, number of attempts required to establish VC, pain, and evaluation. RESULTS: All procedures were performed with NO while four VC (8%) were not possible to perform with CO. The number of attempts required to establish VC was lower when using NO (median 2, range 2-9), compared with CO (median 4, range 2-9). The estimated pain was lower with NO. The total mean time required was similar for NO and CO when the time required for the NO procedure was included. One complication, tinnitus, was observed; it disappeared within 3 minutes. CONCLUSION: The pretreatment with nitrous oxide is a time effective and safe method for use at paediatric outpatient departments to reduce pain, facilitate venous cannulation, and thereby reduce the number of costly cancellations of planned procedures.  (+info)

Alkalinisation of local anaesthetics prescribed for pain relief after surgical decompression of carpal tunnel syndrome. (35/141)

PURPOSE: To compare the duration of analgesia achieved following administration of buffered prilocaine versus plain prilocaine to patients undergoing surgical decompression of the median nerve. METHODS: 40 (32 female and 8 male; mean age, 50.5 years) patients who underwent surgical decompression of carpal tunnel syndrome were recruited. Patients were randomly allocated to 2 groups: the alkalinised group was given 10 ml of prilocaine hydrochloride 2% buffered with 1 ml of sodium bicarbonate 8.4%, whereas the non-alkalinised group received 10 ml of plain prilocaine hydrochloride 2% solution. Patients were asked to rate their comfort level at the operation site in the first 6 hours following surgery and after discharge from hospital using a visual analogue scale (VAS). The duration of analgesic effect was evaluated every 3 hours. Additional oral analgesia in the form of paracetamol 500 mg tablets was available to patients if required for break-through pain. RESULTS: Significantly lower VAS scores were reported by the alkalinised group during the first postoperative 12 hours. The change of VAS scores over time was significantly higher in the non-alkalinised group. The mean analgesic requirement for paracetamol tablets in the alkalinised and non-alkalinised groups was 4 and 34, respectively. CONCLUSION: Buffered prilocaine provided a longer postoperative pain-free period for patients undergoing surgical decompression of the median nerve. It is easy, safe, and cost-effective.  (+info)

Ultralong peripheral nerve block by lidocaine:prilocaine 1:1 mixture in a lipid depot formulation: comparison of in vitro, in vivo, and effect kinetics. (36/141)

BACKGROUND: The aim of this study was to develop stable and easily injectable lipid depot preparations of local anesthetics in which the drug concentration can be varied according to desired duration of action. METHODS: The formulations contained a 2.0, 5.0, 10, 20, 40, 60, 80, or 100% eutectic mixture of lidocaine and prilocaine base in medium-chain triglyceride. Duration of sciatic nerve block and local neurotoxicity was investigated in rats with 2.0% lidocaine:prilocaine HCl solution and 99.5% ethanol as controls. The rate of release of local anesthetic from the site of administration and the possibility to predict in vivo depot characteristics from in vitro release data were investigated for the 20 and 60% formulations. RESULTS: The duration of sensory sciatic block was prolonged 3 times with the 20% formulation and approximately 180 times with the 60% formulation, in comparison with the 2% aqueous solution. With the 80 and 100% formulations, all animals still showed nerve block after 2 weeks. The in vivo release of local anesthetic could be approximately predicted from in vitro data for the 20% but not for the 60% formulation. The formulations of 60% or greater and ethanol showed neurotoxic effects. CONCLUSIONS: The pharmaceutical properties of these formulations compare favorably with those of other depot preparations. The high-percentage ones showed the longest duration of action yet reported for sciatic nerve block in rats. The possibility of using a high-concentration local anesthetic depot formulation as an alternative to ethanol or phenol for long-term nerve blocks in chronic pain merits further investigation.  (+info)

Comparison of ropivacaine 2 mg ml(-1) and prilocaine 5 mg ml(-1) for i.v. regional anaesthesia in outpatient surgery. (37/141)

BACKGROUND: Ropivacaine 2 mg ml(-1) (0.2%) provides longer-lasting analgesia after deflation of the tourniquet cuff, with fewer side-effects, than lidocaine 5 mg ml(-1) (0.5%) after i.v. regional anaesthesia (IVRA). Whether ropivacaine 2 mg ml(-1) also exerts this advantage over prilocaine 5 mg ml(-1), the local anaesthetic of choice in IVRA in most European countries was investigated in this study. METHODS: Sixty outpatients scheduled for forearm or hand surgery received IVRA with 40 ml of ropivacaine 2 mg ml(-1) (Ropi) or prilocaine 5 mg ml(-1) (Prilo) in a randomized, double-blinded fashion. The development and recovery of pin-prick analgesia and motor power of the hand, as well as ropivacaine and prilocaine plasma concentrations (n=30), were assessed during and after operation. RESULTS: Anaesthesia for surgery was adequate in both groups. Pin-prick analgesia was achieved at a similar rate, except in the radial nerve distribution area where at 10 min 60% of Ropi and 90% of Prilo patients had analgesia (P=0.017). At 10 min 100 and 97% had motor block of the hand in the Ropi and Prilo groups, respectively. Recovery of the sensory block in all innervation areas was already observed 2 min after the tourniquet cuff release. At 10 min after releasing the tourniquet cuff 31% of the Ropi patients and none of the Prilo patients still had analgesia in the median nerve distribution (P=0.004). At 12 min, 42% in the Ropi group and none in the Prilo group had decreased grip strength. After the release of the tourniquet, mean plasma concentrations of ropivacaine were higher than those of prilocaine. The highest individual concentration of ropivacaine was 1.65 microg ml(-1) and that of prilocaine 0.6 microg ml(-1). None of the Ropi patients experienced any symptoms of local anaesthetic toxicity. CONCLUSIONS: Compared with prilocaine 5 mg ml(-1), analgesia in IVRA with ropivacaine 2 mg ml(-1) developed slightly more slowly, while motor block developed at a similar rate. After the release of the tourniquet, sensation recovered quickly and at a similar rate in the two groups, except for a slightly slower recovery after ropivacaine in the innervation area of the median nerve, but no surgically useful extended analgesia after the cuff deflation was observed. Despite a 60% lower milligram-dose, ropivacaine plasma concentrations were markedly higher than those of prilocaine.  (+info)

Evaluation of three topical anaesthetic agents against pain: a clinical study. (38/141)

AIM: To compare pain responses of children during local anaesthetic infiltration at bilateral buccal sites prepared with topical application of EMLA 5% cream, benzocaine 18% gel or lignocaine 5% ointment and also to find out the rapidity of onset of action of these agents. METHODS: 60 healthy children aged 6 to 12 years old, received bilateral buccal infiltration following application of topical anaesthetic agents applied in a double blind design. Pain responses were compared based on subject self report using visual analogue scale (VAS) and operator assessment using Sound -Eye -Motor (SEM) scale. RESULTS: Benzocaine gel had the rapidest onset of action. EMLA 5% cream proved to be superior in pain reduction compared to benzocaine and lignocaine. Taste acceptance was better with benzocaine gel. Further studies are required for EMLA cream with an improved formulation more suitable for mucosal application before its routine use in dentistry.  (+info)

Lidocaine-prilocaine (EMLA) cream as analgesia for hysterosalpingography: a prospective, randomized, controlled, double blinded study. (39/141)

BACKGROUND: The aim of our study is to evaluate the efficacy of applying lidocaine 25 mg-prilocaine-25 mg/G cream (EMLA 5%) on the uterine cervix for pain relief when performing hysterosalpingography (HSG). METHODS: Eighty-two patients undergoing HSG as part of infertility evaluation were randomized into groups receiving EMLA (42) or placebo cream (40) in a double-blinded prospective study from which four women were later excluded. The cream was applied to the uterine cervix by means of a cervical cup 30 min before the HSG. Pain perception related to the HSG procedure was scored by visual analogue scale (VAS) at five predefined steps: after speculum application, after cervical instrumentation of the tenaculum and cannula, at the end of uterine filling, at completion of tubal spillage, and immediately following instrument removal. In addition, the patients were asked to retrospectively rate the pain during the entire procedure in a telephone interview the following day. RESULTS: Cervical instrumentation was found to be the most painful step of HSG (P < 0.001). When comparing the VAS pain scores, cervical instrumentation in the EMLA-treated patients was associated with significantly less pain than the control group: 3.3 +/- 2.9 versus 4.9 +/- 2.7, respectively (P = 0.02). CONCLUSIONS: Topical application of EMLA 5% cream on the uterine cervix before performing HSG significantly reduced the pain during this procedure.  (+info)

Percutaneous penetration kinetics of lidocaine and prilocaine in two local anesthetic formulations assessed by in vivo microdialysis in pigs. (40/141)

The aim of this study was to characterize and compare the percutaneous penetration kinetics of lidocaine (L) and prilocaine (P) in two local anesthetic formulations by in vivo microdialysis coupled with HPLC. The microdialysis system for studying lidocaine and prilocaine was calibrated by a no-net-flux method in vitro and retrodialysis method in vivo, respectively. A dosage of 0.2 g/cm2 of an in-house P-L formulation (2.5% lidocaine and 2.5% prilocaine, methylcellulose-based) and commercially available Eutectic Mixture of Local Anesthesia (EMLA, 2.5% lidocaine and 2.5% prilocaine, carbopol-based) was separately but symmetrically applied in the dorsal region of pigs. Saline (0.9%, w/v) was perfused into the linear microdialysis probe at a flow rate of 1.5 microl/min. Dialysate was collected upon topical application up to 6 h at 20-min intervals and assessed by HPLC. The results demonstrated the area under the concentration-time curve (AUC(0-6 h)) of lidocaine and prilocaine in EMLA was 71.95+/-23.36 microg h/ml and 38.01+/-14.8 microg h/ml, respectively, in comparison to 167.11+/-56.12 microg h/ml and 87.02+/-30.38 microg h/ml in the P-L formulation. The maximal concentrations (Cmax) of lidocaine and prilocaine in the dermis were 29.2+/-9.08 microg/ml and 16.54+/-5.31 microg/ml in EMLA and 80.93+/-17.98 microg/ml and 43.69+/-12.87 microg/ml in the P-L formulation, respectively. This study indicates a well-calibrated microdialysis system can provide vital real-time information on percutaneous drug delivery and specifically a methylcellulose-based P-L formulation can increase percutaneous absorption of both lidocaine and prilocaine in pigs compared to carbopol-based EMLA.  (+info)