Search the Protocols

List of Donors

Make a donation to the protocols online

KLS Martin, LP

Hemostatix Medical Technologies, LLC

Cook Medical

Karl and Kay Rinehart

Boston Medical Products Inc.


Jon and Veda Foster


Synovis Micro Companies Alliance, Inc

Tom Benda, JR., M.D.

The Potash Family

UIHC Melanoma and Sarcoma Tissue Bank

Karl Storz-Endoskope

Heartland Regional Chapter of SOHN



The Department of Otolaryngology and the University of Iowa wish to acknowledge the support of those who share our goal in improving the care of patients we serve. The University of Iowa appreciates that supporting benefactors recognize the University of Iowa's need for autonomy in the development of the content of the Iowa Head and Neck Protocols.

HaN Admin Pages

Skip to end of metadata
Go to start of metadata



Local Anesthesia Topics

        • 0.15 mL of a 1-mg/mL solution of epinephrine to 30 mL of local anesthetic agent yields a 1:200,000 solution
          • Solutions of epinephrine more concentrated than 1:100,000 provide no additional clinical vasoconstriction, and increase the risk for epinephrine toxicity
          • reverse ischemia with phentolamine
        • Premixed solutions containing epinephrine are acidified to a pH of 3 to 4.5 to stabilize the epinephrine component from spontaneous hydrolysis, which increases its shelf life but also alters the pharmacodynamic properties of the solution (makes it more acidic!, more painful, longer onset)
          • At an acidic pH (as in most local anesthetic solutions or infected tissues), almost all the anesthetic is in the cationic form, which delays the onset of action
        • Relative contraindications:  (consider phenylephrine)
          • history of unstable angina, cardiac dysrhythmias, uncontrolled hypertension
            • limit to 0.04mg (4ml) in pts with cardiac hx
          • uteroplacental insufficiency related to pregnancy
          • hyperthyroidism
          • concurrent use of agents that alter the effects of catecholamines (eg. monoamine oxidase inhibitors or tricyclic antidepressants)
        • Other uses:
          • Adult anaphylactic dose = 0.3-0.5mg
          • Cardiac arrest = 1mg
      • Phenylephrine 
        • 1:20,000 or 1:50,000 dilution often an adequate substitute for epinephrine where there are medical contraindications.
        • must wait 15-20min
        • less effective, shorter duration
        • Mechanism: produces peripheral vasoconstriction without the cardiac effects
      • COCAINE - ONLY anesthetic with vasoconstrictive properties 
        • Mechanism: 
          • blocks sodium channels -> analgesia
          • blocks Norepinephrine reuptake of sympathetics -> vasoconstriction
        • 2-3 mg/kg or 200 mg
        • We use it intranasally 4 ml of 4% (40 mg/ml) = 160 mg
      • Lidocaine 
        • 1% = 1g/100ml = 1000mg/100ml = 10mg/ml
        • 2% = 20mg/ml
        • max dose:
          • 4 mg/kg w/o epi (280mg max for 70kg pt = 28 ml w/o)
          • 7 mg/kg w/ epi (500 mg max for 70kg pt = 50 ml)
      • Marcaine (Bupivacaine)
        • 0.25% w/ 1:200,000 epi = 2.5mg/ml
        • max dose:
          • 3 mg/kg w/ (225 mg max = 90ml) 
          • 2 mg/kg w/o (175mg max = 70ml)
        • *generally not recommended in peds (low max dosing volumes)
      • Benzocaine
        • 1 second spray of 20% benzocaine delivers 0.5 ml (100 mg)
          • very easy to give substantial doses of benzocaine with even conservative use of this drug
          • for this reason, applications are limited
          • general guidelines:  spray <1 second, no more than 2 sprays total
        • Caution:
          • Risk for methemoglobinemia
          • Patients with G-6-PD deficiency, cholinesterase deficiency (succinylcholine sensitivity) or congenital abnormalities of methemoglobin reductase are at greatest risk
          • Methemoglobinemia has been reported with benzocaine doses as small as 150 mg
    • Iontophoresis for myringotomy or ear procedures under local anesthesia



  • No labels