Concept: Local anesthetics
Local anesthetic agents such as bupivacaine and lidocaine are commonly used after surgery for pain control. The aim of this prospective study was to evaluate the safety of a mixture of bupivacaine and lidocaine in children who underwent urologic inguinal and scrotal surgery.
Ear tattooing is a routine procedure performed on laboratory, commercial and companion rabbits for the purpose of identification. Although this procedure is potentially painful, it is usually performed without the provision of analgesia, so compromising animal welfare. Furthermore, current means to assess pain in rabbits are poor and more reliable methods are required. The objectives of this study were to assess the physiological and behavioural effects of ear tattooing on rabbits, evaluate the analgesic efficacy of topical local anaesthetic cream application prior to this procedure, and to develop a scale to assess pain in rabbits based on changes in facial expression.
Venipuncture and intravenous cannulation are the most common painful procedures performed on children. The most widely used topical anesthetic is eutectic mixture of local anesthetics (EMLA). EMLA use is associated with a transient cutaneous vasoconstriction which can make it difficult to identify veins. We assessed with a prospective, multicenter, observational study whether EMLA interferes with venipuncture and intravenous cannulation. The primary study outcome was a success at first attempt in the course of venipuncture or venous cannulation. The study enrolled 388 children; 255 of them received EMLA and 133 did not. Eighty-six percent of procedures were successful at the first attempt in the EMLA group and 76.7 % in the no EMLA group. Conclusion: In this study, EMLA use did not interfere with the success of venipuncture or venous cannulation in children.
Molecular Dynamic Simulations are performed to evaluate the interaction of lidocaine, procaine and tetracaine with a lipid membrane. The main interest is to evaluate the structural changes produced by these local anesthetics in the bilayers. Penetration trajectories, interaction energies, entropy changes and an order parameter are calculated to quantify the destabilization of the lipid configurations. We show that such structural parameters give important information to understand how anesthetic agents influence the structure of plasma membranes. Graphic processing units (GPUs) are used in our simulations.
Iontophoresis is a strategy to increase the penetration of drugs through biological membranes; however, its use has been underexplored in mucosa. The aim of this work was to investigate the influence of iontophoresis in the mucosal penetration of prilocaine hydrochloride (PCL) and lidocaine hydrochloride (LCL), which are largely used in dentistry as local anesthetics, when combined in the same formulation. Semisolid hydrogels containing these drugs either alone or in combination were developed at two different pHs (7.0 and 5.8) and presented adequate mechanical and mucoadhesive properties for buccal administration. The distribution coefficients between the mucosa and the formulations (Dm/f) and the in vitro mucosa permeation and retention rates were evaluated for both PCL and LCL. At pH 7.0, the combination of the drugs decreased the Dm/f of PCL by approximately 3-fold but did not change the Dm/f of LCL; iontophoresis increased the permeation rate of PCL by 12-fold and did not significantly change LCL flux compared with the passive permeation rate of the combined drugs. Combining the drugs also resulted in an increase in both PCL (86-fold) and LCL (12-fold) accumulation in the mucosa after iontophoresis at pH 7.0 compared with iontophoresis of the isolated drugs. Therefore, applying iontophoresis to a semisolid formulation of this drug combination at pH 7.0 can serve as a needle-free strategy to speed the onset and prolong the duration of buccal anesthesia.
To compare the intraoperative and postoperative clinical properties of 1% ropivacaine, 0.75% bupivacaine, 2% lidocaine and a mixture of 0.75% bupivacaine and 2% lidocaine (bupi+lido) administered for peribulbar anaesthesia during vitrectomy.
Intravenous lipid emulsion (ILE) has gained favor as a rescue treatment for cardiovascular collapse due to intravenous local anesthetic overdose, however, goals of ILE therapy are still being defined. We describe a case of a girl given 66 mL/kg of 20% lipid emulsion (ILE) in the treatment of presumed mepivacaine toxicity.
A variety of topical anesthetic creams are available to reduce pain associated with dermatological procedures. Pliaglis is a self-occluding eutectic mixture of lidocaine and tetracaine.
Needle insertion is a routine procedure performed on cancer patients with totally implantable venous access device. Although this procedure is painful for most of the patients, it is regularly performed without topical application of local anesthetics. In our study, we assess the degree of pain associated with different duration times of EMLA cream.
The aim of this study was to compare the incidences of leakage from the catheter insertion site during continuous femoral nerve block when using the catheter-through-needle, Contiplex Touhy™ (CT) and the newly developed catheter-over-needle, Contiplex C™ (CC). Forty adult patients who were scheduled to undergo continuous femoral nerve block for pain control following knee surgery were enrolled and were randomly assigned to a CT group or a CC group. After finishing surgery, a catheter for continuous femoral nerve block was placed using ultrasound. A catheter was advanced along the femoral nerve 5-6 cm beyond the needle tip. Then 0.25% levobupivacaine was continuously administered at a rate of 5 ml/h until 9:00 am on postoperative day 1. The incidence of leakage of the local anesthetic from the insertion site in the CT group was significantly higher than that in the CC group. In the CT group, leakage from the catheter insertion site was observed in 11 of 20 patients during the observation period. On the other hand, none of the patients in the CC group showed leakage. Contiplex C™ is more effective than Contiplex Touphy™ for prevention of leakage of local anesthetics from the insertion site during continuous femoral nerve block.