Lidocaine-based topical anesthetic with disinfectant (LidoDin) versus EMLA for venipuncture: a randomized controlled trial.

OBJECTIVE: To examine the efficacy and safety of a new topical anesthetic containing a disinfection ingredient (LidoDin cream) in reducing the pain associated with venipuncture by comparing it with the proven eutectic mixture of lidocaine 2.5% and prilocaine 2.5% (EMLA cream). METHODS: A single-blind, randomized, controlled trial was conducted on a study population consisting of a convenience sample of patients aged 12 to 16 years who presented at our Emergency Department between November 2007 and April 2008. The Visual Analog Scale (VAS) was used for pain assessment. Before the study, the bactericidal effect of the LidoDin cream on skin flora was tested. RESULTS: Twenty patients were enrolled to each arm of the study. Mean patient age was 13.6 years for the LidoDin group and 14.12 years for the EMLA group (P=0.347). Male patients accounted for 55% of the patients in the LidoDin group, compared with 40% in the EMLA group (P=0.527). Skin reaction scores of the LidoDin group for erythema and edema were not statistically different than those of the EMLA group (P=0.73 and P=0.75, respectively). Patient VAS scores and nurse VAS scores of the LidoDin group were not statistically different than those of the EMLA group (P=0.57 and P=0.93, respectively). DISCUSSION: This pilot study demonstrated that LidoDin and EMLA seem to be equally safe and effective topical anesthetics for venipuncture. Future studies are planned to determine, if LidoDin reduces the rate of local skin infection in patients treated with multiple daily subcutaneous injections of medications.

Delayed hypersensitivity reaction from black henna tattoo manifesting as severe facial swelling.

We report on a 14-year-old boy who was presented to the emergency department with an acute swelling of the face and scalp 3 days after using a new hair dye. The patient had applied a black henna tattoo 1 year earlier. Patch testing revealed an allergy to the potent skin sensitizer paraphenylenediamine, a common ingredient of hair dyes and also found in black henna tattoo. It is important for emergency physicians to be aware of the possibility of a delayed type-IV hypersensitivity reaction from black henna tattoos manifesting as an acute contact dermatitis. These patients may have gross facial swelling but should not be treated for angioedema.

Comparison of blood pressure measurements on the bare arm, below a rolled-up sleeve, or over a sleeve.

BACKGROUND: This study examined the effect of measuring blood pressure below subjects' rolled-up sleeves, over the sleeve, or on the bare arm. This is an important day-to-day issue for the busy GP. METHODS: The sample consisted of 201 subjects in family practice clinics and residents of a senior citizens' home. A digital device was used in all cases. Each participant underwent three blood pressure measurements in each of the following conditions in random order: cuff on bare arm; cuff over the sleeve; and cuff below the rolled-up sleeve. Differences between measurements were plotted against the mean blood pressure. Confounding factors controlled for were age, sex, clothing pressure and skin-fold thickness. RESULTS: Differences in mean blood pressure readings between the clothed and bare arm were 0.5 mmHg (SD 7.5) for systolic pressure and 1 mmHg (SD 5) for diastolic pressure; neither difference was significant. However, in hypertensive subjects (>140 mmHg systolic), although the mean difference remained small (systolic pressure, 2 mmHg, SD 10), the range of difference for individual subjects was -32 mmHg to +22 mmHg. CONCLUSION: The degree of clothing under the sphygmomanometer cuff does not have a clinically important effect on the blood pressure measurement. In patients known or found to be hypertensive, measurement on the bare arm is recommended.