SummaryThe vasoactive properties of EMLA (eutectic mixture of local anaesthetic) and amethocaine were compared using Doppler colour ultrasound to measure vein diameter in 20 male volunteers. EMLA or amethocaine cream were applied over veins on the dorsum of the hand and vein diameter was measured prior to application of the preparations and at 1, 1.5 and 2 h after removal. Visual analogue scores for skin colour and vasodilatation were performed at 1 h. The results showed no significant difference in vein diameter between the EMLA and amethocaine groups. However, the amethocaine-treated hands were significantly more erythematous at 1 h (p`0.00002).Keywords Anaesthetics, local; topical, EMLA, amethocaine EMLA cream (Astra Pharmaceuticals), a eutectic mixture of the two amide local anaesthetics, lignocaine and prilocaine, is a topical local anaesthetic preparation for reducing the pain of intravenous cannulation. It is generally perceived that venous cannulation is more difficult after the application of EMLA cream due to local vasoconstriction. This has been substantiated by various studies; qualitative studies have assessed skin colour and skin blanching, and have blindly scored ease of cannulation [1][2][3]. More quantitative studies have measured local blood content using Doppler colour ultrasound and blood flow using laser Doppler flowmetry [4]. However, there have been no studies in which the diameter of superficial cutaneous veins deemed suitable for venous cannulation were measured directly, and therefore the effect of EMLA on venous diameter quantified.Strategies to reduce this vasoconstrictor action include combining EMLA with venodilators such as glyceral trinitrate (GTN) and removing EMLA for a period prior to venepuncture. The combination of EMLA and GTN has been shown to increase the ease of venepuncture [3, 5]. Removal of the EMLA at some time prior to venepuncture may also be effective in improving conditions for venous cannulation, but is limited by the short duration of topical anaesthesia provided by the EMLA cream.Amethocaine is an ester local anaesthetic which is now available as a topical preparation (Ametop, Smith and Nephew). It has been shown to provide more rapid and prolonged anaesthesia compared with EMLA [6, 7] and has also been reported to have a vasodilator action, which may be a direct action of the drug, or an indirect action due to histamine release. The vascular effects of amethocaine, however, have only been measured in an observational study in which dermal colour change was recorded [8]. We carried out a study to quantify and compare the vasoactive properties of EMLA and amethocaine cream, using Doppler colour ultrasound to measure venous diameter. MethodsAfter obtaining local ethics committee approval, 20 healthy male volunteers were recruited, gave written informed consent and took part in the study. The volunteers attended on two separate occasions at b7-day intervals. The study was a double-blind crossover design, with Anaesthesia, 1999, 54, 466-482 466ᮊ 1998 Blackwel...

Certain adjuvants have been tried with local anaesthetics to enhance analgesic efficacy and extend the analgesic period post operatively. This randomized prospective double blind trial was designed to compare the effects of addition of clonidine to ropivacaine in interscalane brachial plexus block for upper limb surgery. Patients and methods: 60 patients of age group 20-65 years of either sex, admitted to undergo upper limb surgeries were included. Group A-Patients receiving 30ml of 0.75% ropivacaine hydrochloride plus 1ml normal saline. Group B-Patients receiving 30ml of 0.75% ropivacaine hydrochloride plus 150mcg clonidine (1ml). Results: The total duration of sensory block in group A was 7.61 + 1.62 hours while in group B was 11.62 + 1.84 hours. Total duration of motor block in group A was 5.95 + 1.38 hours while in group B was 9.82 + 1.98 hours. Duration of post-operative analgesia in group A it was 7.24 + 1.36 hours and in group B it was 11.83 + 2.33 hours. Haemodynamically both groups were stable perioperatively. Patient satisfaction score was better in group B. Conclusion: In conclusion, clonidine added to ropivacaine is an attractive option for improving the quality and duration of interscalene brachial plexus block in upper limb surgeries with stable perioperative hemodynamics.

BACKGROUNDLumbosacral radiculopathy is a common medical and socioeconomic problem with a lifetime prevalence estimated to be around 40%-60%. In 1930, Evans reported that sciatica could be treated by epidural injection. The use of epidural corticosteroid injection for the treatment of axial and radicular back pain was first reported in 1953. Lumbar Transforminal Epidural Steroid Injections (TFESIs) are performed to provide symptomatic relief in patients with radicular pain. A transforaminal epidural steroid injection (TFESI) using a small volume of local anaesthetic will anaesthetize the spinal nerve and also partially anaesthetize the dura, the posterior longitudinal ligament, the intervertebral disc and facet joint. For these reasons, fluoroscopy-guided TFESI has become the preferred approach to epidural space.

BACKGROUNDThe introduction of safe drugs enhanced the popularity of spinal anaesthesia. Lofgren and Lundqvist introduced the most commonly used drug, Lignocaine. One of the disadvantages of Lignocaine was the association with transient neurological symptoms, which presents as low backache and lower extremity dysesthesia. Bupivacaine was introduced by Ekenstam in 1957. It is a well-established long-acting local anaesthetic used for spinal anaesthesia. It has been used frequently in spinal anaesthesia with a very little incidence of transient neurological symptoms. But it is associated with cardiovascular and central nervous system toxicity when used in high concentration or when accidentally administered intravascularly. Ropivacaine was introduced into clinical practice in 1996. It was initially used in epidural anaesthesia in lower extremity surgery, where it was compared with bupivacaine where they concluded that ropivacaine produced similar sensory and motor blockade with less cardiotoxicity. In a study, different concentrations of intrathecal ropivacaine 0.5% and 0.75% were compared for vascular surgery, which concluded that 15 mg of plain ropivacaine 0.75% is effective and safe and gives complete spinal anaesthesia in high risk patients without side effects and cardiovascular modifications.The aim of this study was to compare and evaluate the haemodynamic changes and side effects associated with equal volumes of two different doses of ropivacaine hydrochloride (0.75% and 0.5%) used in spinal anaesthesia in lower limb orthopaedic surgeries.

BACKGROUNDCentral neuraxial blockade is a major regional anaesthesia technique with a long history of effective use for a variety of surgical procedures and pain relief. Ropivacaine is an amino-amide local anaesthetic drug, which was first synthesised in 1957 and was introduced into clinical practice in 1996. As there are limited studies on effect of ropivacaine in spinal anaesthesia, we conducted a dose comparison study of ropivacaine in our institute to know the clinical efficacy and safety with regard to better patient profile management.The aim of the study was to compare and evaluate equal volumes of two different doses of ropivacaine hydrochloride (0.75% and 0.5%) in spinal anaesthesia in lower limb orthopaedic surgeries with regard to the onset and duration of sensory and motor blockade. MATERIALS AND METHODSIt is a prospective, randomised, double-blind study conducted in a tertiary care hospital in which 80 patients of age group 20 -65 years of either sex which were scheduled to undergo lower limb orthopaedic surgeries under spinal anaesthesia with two different doses of Ropivacaine Hydrochloride were included. The patients were randomly divided into 2 groups of 40 each. Group A received 22.5 mg (3 mL) of 0.75% isobaric Ropivacaine Hydrochloride. Group B patients received 15 mg (3 mL) of 0.5% isobaric Ropivacaine Hydrochloride. RESULTSRopivacaine 0.75% produced higher level and longer duration of sensory blockade than ropivacaine 0.5% when used in spinal anaesthesia. Thus, there was longer duration of analgesia with ropivacaine 0.75%. The ropivacaine 0.75% solution resulted in higher frequency and longer duration of motor block in the lower limbs than ropivacaine 0.5%. Thus, a reliable motor blockade was obtained with ropivacaine 0.75%. Therefore, it is concluded that intrathecal ropivacaine 0.75% provides an excellent sensory blockade with longer duration of analgesia and a complete motor block, which makes it suitable for lower limb orthopaedic surgeries requiring an intense sensory and motor blockade. CONCLUSIONOur study suggests the use of ropivacaine 0.75% for spinal anaesthesia in lower limb orthopaedic surgeries, as it provides prolonged duration of sensory and profound motor blockade of lower limbs.