PHARMACY UPDATE
Topical anaesthetics: What’s new? Kelly D Young
Correspondence to Dr Kelly D Young, Department of Emergency Medicine, David Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center, 1000 W. Carson Street, Box 21, Building D-9, Torrance, CA 90275, USA; [email protected] Received 4 February 2014 Revised 22 May 2014 Accepted 12 June 2014 Published Online First 2 July 2014
To cite: Young KD. Arch Dis Child Educ Pract Ed 2015;100:105–110.
ABSTRACT Topical anaesthetics, often used by anaesthetists, dentists and dermatologists, have increasingly been recognised for their utility in paediatrics. With topical anaesthetics, the ‘ouchless’ paediatric practice becomes an achievable goal. The primary drawback to their use is the length of time for anaesthetic effect, but planning ahead and making use of newer formulations and adjuncts can overcome this barrier. This update will review topical anaesthetic formulations available, adjuncts to reduce the time to anaesthesia, adverse effects, common indications and products on the horizon.
TOPICAL ANAESTHETICS FOR INTACT SKIN Several products are available for use on intact skin (table 1). The pain of any skinbreaking procedure such as venipuncture, intravenous catheter placement, intramuscular injection, vaccination, arterial puncture or local anaesthetic infiltration prior to lumbar puncture or abscess incision and drainage can be reduced with these topical anaesthetics.1 Eutectic mixture of local anaesthetics (EMLA) should be applied under an occlusive dressing; plastic wrap secured with tape is a low-cost option. A strip squeezed out of the tube that is 1.5 inches×0.2 inches (38 mm×5 mm) is 1 g. On intact non-mucosal skin, depth of anaesthesia reaches 3 mm after 60 min and 5 mm after 120 min. Although EMLA produces vasoconstriction and blanching, it does not decrease vein catheterisation success.2 The prilocaine component of EMLA increases the risk of the rare adverse effect methemoglobinemia. EMLA is not approved for neonates 10 kg: 10 g per 100 cm2 BSA for 4 h 7–12 years old and >20 kg: 20 g per 200 cm2 BSA for 4h
LMX4, LMX5
5, 15 and 30 g tubes; LMX4 widely available throughout the world
4% and 5% liposomal lidocaine
Liposomes
30 min
60 min after removal of cream
1 g per 10 cm2 BSA. Do not apply >1 g in 5 h in 12 months and older. Not recommended for 5 years old, 7 tubes in adults; not recommended in
Topical anaesthetics: What’s new? Kelly D Young
Correspondence to Dr Kelly D Young, Department of Emergency Medicine, David Geffen School of Medicine at UCLA, Harbor-UCLA Medical Center, 1000 W. Carson Street, Box 21, Building D-9, Torrance, CA 90275, USA; [email protected] Received 4 February 2014 Revised 22 May 2014 Accepted 12 June 2014 Published Online First 2 July 2014
To cite: Young KD. Arch Dis Child Educ Pract Ed 2015;100:105–110.
ABSTRACT Topical anaesthetics, often used by anaesthetists, dentists and dermatologists, have increasingly been recognised for their utility in paediatrics. With topical anaesthetics, the ‘ouchless’ paediatric practice becomes an achievable goal. The primary drawback to their use is the length of time for anaesthetic effect, but planning ahead and making use of newer formulations and adjuncts can overcome this barrier. This update will review topical anaesthetic formulations available, adjuncts to reduce the time to anaesthesia, adverse effects, common indications and products on the horizon.
TOPICAL ANAESTHETICS FOR INTACT SKIN Several products are available for use on intact skin (table 1). The pain of any skinbreaking procedure such as venipuncture, intravenous catheter placement, intramuscular injection, vaccination, arterial puncture or local anaesthetic infiltration prior to lumbar puncture or abscess incision and drainage can be reduced with these topical anaesthetics.1 Eutectic mixture of local anaesthetics (EMLA) should be applied under an occlusive dressing; plastic wrap secured with tape is a low-cost option. A strip squeezed out of the tube that is 1.5 inches×0.2 inches (38 mm×5 mm) is 1 g. On intact non-mucosal skin, depth of anaesthesia reaches 3 mm after 60 min and 5 mm after 120 min. Although EMLA produces vasoconstriction and blanching, it does not decrease vein catheterisation success.2 The prilocaine component of EMLA increases the risk of the rare adverse effect methemoglobinemia. EMLA is not approved for neonates 10 kg: 10 g per 100 cm2 BSA for 4 h 7–12 years old and >20 kg: 20 g per 200 cm2 BSA for 4h
LMX4, LMX5
5, 15 and 30 g tubes; LMX4 widely available throughout the world
4% and 5% liposomal lidocaine
Liposomes
30 min
60 min after removal of cream
1 g per 10 cm2 BSA. Do not apply >1 g in 5 h in 12 months and older. Not recommended for 5 years old, 7 tubes in adults; not recommended in
