Question

Marilu Lin is a 10-year-old girl undergoing a type II tympanoplasty procedure. The back table and Mayo stand are set up, but the procedure has not yet begun. You are asked to relieve the surgical technologist in the scrub role (STSR) and start the case. She has several medications on the back table, but none of them are labeled. 2. Which medications do you expect to be on the back table? 3. What is the purpose for each medication? 4. What route is used for each? 5. What could happen if these two medications are switched and the epinephrine 1:1000 is injected?

Answer 1

2) I expect the medication that is available on the back table used in type II Tympanoplasty :

Lidocaine with epinephrine :0.5% lidocaine with (1:20,000) Epinephrine :1% with 1:10,000 if the patient id below 12years.Th dose should not exceed 7mg/kg body weight(20ml for average adult) or Lidocaine substituted or partially mixed with Bupivacaine 1%.

If below or 12years old: Epinephrine(1:50,000):(1:20,000)

• 6-12 yrs: 0.3mg IM
• 6Months - 6years:0.15mg IM
• Under 6 months:0.01mg/kg IM

Other material present on the back of table:

• Leica microscope
• Bishop Harmon irrigation set
• Currette tray
• Ear basic tray
• Myringotomy tray
• Cartilage microtome tray
• Clear sticky drape or 1010 drape
• Mastoid tray

3) Medication purpose:

• Lidocaine 2% bolus is given via intravenous route used as prophylaxis for Arrthymias.
• Epinephrine (1:10,000) is applied to the tympanic membrane to induce vasodialation of the blood vessel Alternative :Topical oxymetazoline 0.05% is used for vasoconstriction

4) In Pediatrics: The key for successful surgery is adequate injection.

Epinephrine:

• Inject that dose of not more than 0.8ml of 1:50,000 Epinephrine
• Place the ear speculum the canal to pooch at the bony cartilageous junction.Inject subcutaneously in to the canal skin at the 12 o'clock,3 o'clock,6o'clock and at 9 o'clock positions just proximal to the bony cartilaginous.Inject through slow IV at the canal skin, stop the injection and move to other spot if a bleb a raised.

Lidocaine: Inject 0.5% solution (1:20,000) subcutaneous in to the post auricular crease.

5) If epinephrine 1mg/ml (1:1000) is injected that may produce necrosis at the site of injection and prolonged administration may cause metabolic acidosis,renal necrosis.