Anaesthesia prilocaine

Infiltration anaesthesia is applied fan-shaped, with as few needle punctures as possible, in close proximity of the wound or the skin area to be treated. An aspiration should always take place to avoid intravascular injection. Suitable alternatives are lidocaine (lignocaine) or prilocaine for injection 5-10 mg/ml, with or without adrenaline. When making an incision of an abscess it is sometimes difficult to use a local anaesthetic if there is a pronounced inflammatory reaction, since the effect of the anaesthetic is reduced due to an increased acidity level. While adrenaline reduces bleeding and delays dispersion of the anaesthetic, local anaesthetic/adrenaline combinations are contraindicated for local anaesthesia of digits, on the face or where the skin survival is at risk. 

Nerve block anaesthesia in general practice mostly concerns finger or toe blocks. Lidocaine or prilocaine, 10 mg/ml without adrenaline (norepinephrine), is used and is injected on each side of the finger or toe, in two portions by the four nerve branches. Injection of larger volumes than 1-2 ml/side carries a risk of ischaemia because of the firm tissue. The transport through the nerve sheath takes a few minutes, and for a satisfactory result one should wait 5-10 minutes before the planned intervention starts. 

III.b.8.1. Skin. Surface anaesthesia of the skin can be produced with help of a cream containing a eutectic mixture of local anaesthetics (EMLA), which is a water/oil emulsion of equal parts of prilocaine and lidocaine with particularly good penetration capacity. EMLA is applied under occlusion, around 40-60 minutes before the planned intervention. This is an effective way of producing anaesthesia before needle punctures and minor, painful, procedures. The method is excellent, particularly in paediatrics, to reduce fear and pain. 

Prilocaine is suitable for most types of local anaesthetic block but is not suitable for epidural use in obstetrics because of the need for repeat administration. Its main uses are for infiltration anaesthesia and intravenous regional anaesthesia where its low toxicity makes it the drug of choice. Levobupivacaine... 

Prilocaine is used similarly to lidocaine (t,i 1.5 h), but it is slightly less toxic. It used to be the preferred drug for intravenous regional anaesthesia but it is... 

Similar to Voltaren Emulgel, oily droplets of an eutectic mixture of lidocaine and prilocaine are dispersed in a hydrogel to provide local anaesthesia of the skin for injections and surgical treatment (Emla cream). A further possibility is the dermal administration of a liposome dispersion as a spray (Heparin PUR ratiopharm Spriihgel). After administration, water and isopropyl alcohol evaporate partially to result in an increase of concentration and thereby in a transition from the initial liposome dispersion to a lamellar liquid crystal. The therapeutic effect thus appears to be influenced favorably by the presence of lecithins alone, rather than by the degree of dispersion of liposomes. 

Pitkanen MT, Rosenberg PH, Pere PJ, Tuominen MK, Seppala TA. Fentanyl-prilocaine mixture for intravenous regional anaesthesia in patients undergoing surgery. Anaesthesia 1992 47(5) 395-8. 

Ostgaard G, Hallaraker O, Ulveseth OK, Flaatten H. A randomised study of lidocaine and prilocaine for spinal anaesthesia. Acta Anaesthesiol Scand 2000 44(4) 436-40. 

It is a local anaesthetic of the amide type which is employed for surface, infiltration and nerve block anaesthesia. Its duration of action is in between the shorter-acting lidocaine and longer-acting mepivacaine. It possesses less vaso-dilator activity than lidocaine and hence may be used without adrenaline. Therefore, solutions of prilocaine hydrochloride are specifically beneficial for such patients who cannot tolerate vasopressor agents patients having cardiovascular disorders, diabetes, hypertension and thyrotoxicosis. 

The neuromuscular blockade due to suxamethonium (succinyl-choline) can be increased and prolonged by lidocaine, procaine and possibly procainamide. These local anaesthetics all have some neuromuscular blocking activity and may theoretically also enhance the block produced by competitive neuromuscular blockers. Increased toxicity occurred when mivacurium and prilocaine were given together for regional anaesthesia. 

In a study of 10 healthy subj ects, prolonged muscle weakness and symptoms of local anaesthetic toxicity were experienced after deflation of the tourniquet when 40 mL of prilocaine 0.5% and mivacurium 600 micrograms were used together for intravenous regional anaesthesia of the forearm. Giving prilocaine or mivacurium alone did not produce these effects. The slow recovery suggested that mivacurium was not broken down in the ischaemic limb, but inhibition of plasma cholinesterase by prilocaine would not fully explain the prolonged weakness once the cuff was deflated. ... 

Torrance JM, Lewer BMF, G etfy DC. Low-dose mivacurium siq>plementation of prilocaine i.v. r ional anaesthesia. BrJAnaes (1997) 78,222-3. 

Perovic J, TerzicM, TodorovicL. Safety of local anaesthesia induced by prilocaine with felypressin in patients on tricyclic antidepressants. Bull Group IntRech Sci Stcmatol Odontol... 

Fores Novales B, Aguilera Celorrio L. Spinal myoclonus following intrathecal anaesthesia with prilocaine. Anaesth Intensive Care 2009 37(3) 498-9. 

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