Before reviewing Dr. Trott’s helpful advice, watch the following two YouTube Videos:
How To Apply Topical Anesthesia YouTube Video
Use this medication [EMLA Cream] only on normal skin and the genital area. [from WebMD] Do not apply to broken/irritated skin or open wounds unless directed by your doctor. Wash your hands before using this product.
Apply this product to the area at the proper time as directed. The length of time for the medication to stay on the skin depends on the type of procedure you are having. It is usually applied at least 1 hour before needle sticks and 2 hours before minor skin procedures. It may be applied by a health care professional before certain genital procedures. In this case, it is recommended that you remain lying down so the medication will stay in place.
Repairing Thin (Bleeding) Skin Lacerations of the Elderly YouTube Video Published on Apr 22, 2015 by Dr. Larry Mellick. From the start to 3:45, the video explains “Using L.E.T. for Bleeding (apply lidocaine, epinephrine, and tetracaine to the wound!”
See also COMPOUNDING TOPICAL ANESTHETICS from Rice’s Pharmacy [and perform a Google Search “Making a lidocaine epinephrine tetracaine paste”]
By Melissa Merrell, PharmD, PCCA Director of Formulations and Pharmacy Consultant
All that follows is from Dr. Alxander Trott’s excellent book, Wounds and Lacerations, 4th ed, 2012:
Topical Anesthesia
Indications
Topical anesthesia is an established Method two anesthetize uncomplicated lacerations. (5) pediatric patients are ideal candidates for this technique. It requires no injection and can be administered by the parent. Because of the profuse vascularity of the face and scalp, lacerations of those areas are more effectively anesthetize than the trunk or proximal extremities. Because of tissue absorption of topical agents, this technique is best limited to lacerations of 5 cm less. Contraindicated sites include the finger, toe, nose, pinna of the year, and penis. The death of a 7 1/2 month old infant whose nasal mucous membranes and lips were inadvertently exposed to 10 mL of these solution underscores the need for caution. (34)
In emergency departments with triage systems, topical anesthesia can shorten the patient’s emergency department length of stay and improve the efficiency of care. Topical anesthetics can be applied at the triage for appropriate wounds. They take approximately 20 min. to achieve affect. (35) wounds can be cleaned and repaired in a shortened time frame with good outcomes and improve patient satisfaction. A new or topical preparation, EMLA (eutectic mixture of local anesthetics; see contents of EMLA in the following bulleted list),Has been used in this setting with good effect compared with the standard topical preparations. (36, 37) EMLA has two major drawbacks, however:It is only approved for intact skin (such as for IV needle use) but not for open wounds, and it takes 60 min. to take effect.
Numerous topical anesthetic mixtures have comparable efficacy. . . . Topical anesthetics are commonly prepared as liquid that can be mixed in gels (39) gels can decrease the risk of mucosal exposure and possibly reduce the total dose delivered. The following is a range of topical anesthetic alternatives:
- LAT (lidocaine – adrenaline – tetracaine): Tetracaine (1%), epinephrine (1:2000), and lidocaine (4%) (40)
- TLE (topical lidocaine – epinephrine): lidocaine (5%) and epinephrine (1:2000) (41) these figures represent the final concentrations in dilutions when calculated amounts of each ingredient or combine and brought to a predetermined volume of saline. Preparation of a topical anesthetic solution should be carried out by or under the supervision of a pharmacist.
- LET (lidocaine, epinephrine, tetracaine): lidocaine (2%), epinephrine (1:1000), tetracaine (2%)
- EMLA: eugenic cream mixture, lidocaine (2.5%), Philo Kane (2.5%), suspended in oil and water emulsion
Technique
A 2 x 2 inch sponge is saturatedIs saturated but should not be dripping with solution. The sponges placed in and around the laceration and left for at least 20 min. Shorter application times or associated with higher failure rates. When the smartest fashion to conform to the wound, it can be secured with the tape, and the caregiver or parent should apply gentle manual pressure over the tape sponge. Gloves are recommended to prevent absorption by the caregiver. Common errors include failure to place a sponge fold into the world, “dabbing” the wound, or releasing the manual pressure prematurely. For small lacerations, cotton swabs soaked with the solution can be used. Complete anesthesia is reached when a zone blanching is observed around the world. Find anesthesia is 20 to 30 min. for all frustrations previously listed except for EMLA, which is 60 min.The maximal dose of the solution is to 5 mL. The average wound requires 2 to 3 mL. In approximately 5% of loans, supplemental infiltration is required to achieve complete anesthesia. (42)
References: pp 71 and 72.