Adverse effects of EMLA (lidocaine/prilocaine) cream and efficacy for the placement of jugular catheters in hospitalized cats

Abstract

EMLA is a lidocaine/prilocaine cream used for topical analgesia in human pediatric patients. The purpose of this study was to establish the safety of EMLA in clinically ill cats, to measure systemic absorption and to determine whether EMLA reduced the need for sedation for the placement of jugular catheters. Thirty-one cats were randomized to either a placebo or EMLA cream group. Cream was applied to a 10 cm(2) area over the jugular vein, with 1h of occlusive dressing. Neither anesthetic was systemically absorbed in any cat, and no adverse clinical signs were observed. Struggling during catheter placement was less in the EMLA-treated cats compared to placebo, but did not reach significance (P = 0.06). Jugular catheters were successfully placed in 60% of EMLA-treated cats and 38% of placebo cats; this difference was not statistically significant and may not justify the added steps of EMLA cream administration for this purpose. However, EMLA does appear to be safe in clinically ill cats, and may be useful for other applications such as for skin mass removal or repeated venepuncture.

The clinical efficacy of EMLA cream for intravenous catheter placement in client-owned dogs

“…Other concerns that have been cited for the use of EMLA cream in the clinical setting are the development of local anaesthetic toxicity and methaemoglobinaemia. Although not assessed in this study, previous studies in man and cats have shown that these problems were not encountered during clinical use of EMLA cream (Wagner et al 2006;Robieux et al 1990).…”

Effects of intravenous, low-dose ketamine-diazepam sedation on the results of hematologic, plasma biochemical, and coagulation analyses in cats

“…Attempts to use local anesthetic creams [13][14][15] or facial pheromones 16 to reduce feline struggle reactions during various clinical procedures have both shown limitations. Chemical restraint rather than force thus remains the humane and often safer way to deal with uncooperative animals.…”

A Review on Mitigating Fear and Aggression in Dogs and Cats in a Veterinary Setting

“…In unsedated cats, defensive movements when placing a catheter in the jugular vein tended to decrease one hour after EMLA application, but the level of statistical significance was just missed [72]. In addition, it was observed that some cats did not react to the initial insertion of the needle, but to the progression of the catheter into the vein, so that sedation was necessary for successful catheterisation [72]. If animals subsequently need to undergo anesthesia anyway, [32] intramuscular sedation as a standard procedure before further invasive procedures such as the insertion of a venous catheter in order to minimise the risk of a negative experience is recommended.…”

“…In already sedated cats, a positive effect of EMLA on struggling during jugular catheterisation has been reported just 20 minutes after application [71]. In unsedated cats, defensive movements when placing a catheter in the jugular vein tended to decrease one hour after EMLA application, but the level of statistical significance was just missed [72]. In addition, it was observed that some cats did not react to the initial insertion of the needle, but to the progression of the catheter into the vein, so that sedation was necessary for successful catheterisation [72].…”