Hygiene Atlas

Atlas · Plate VIII · Pharmacology and Local Anesthesia · 10

Vasoconstrictors

Vasoconstrictors slow absorption, lengthen anesthesia, lower toxicity and reduce bleeding. A 1.8 mL cartridge of 1:100,000 epinephrine holds 0.018 mg. A healthy adult may receive up to 0.2 mg per appointment and a cardiovascular-compromised patient 0.04 mg, about two cartridges. Elective use is avoided within 6 months of a heart attack or stroke, with blood pressure over 200/115, or with sulfite allergy.

High-yield facts · 9

  1. Vasoconstrictors slow absorption, lengthen duration, lower toxicity and reduce bleeding.S14
  2. 1:100,000 epinephrine = 0.01 mg/mL = 0.018 mg per 1.8 mL cartridge.S14
  3. 1:200,000 = 0.005 mg/mL (0.009 mg/cartridge); 1:50,000 = 0.02 mg/mL (0.036 mg/cartridge).S14
  4. Healthy adult epinephrine max: 0.2 mg per appointment (about 11 cartridges of 1:100,000).S14T1
  5. Cardiovascular-compromised adult epinephrine max: 0.04 mg per appointment (about 2 cartridges of 1:100,000 or 4 of 1:200,000).S14T1
  6. Levonordefrin 1:20,000 (with 2% mepivacaine) = 0.05 mg/mL; max 1 mg per appointment healthy, 0.2 mg cardiac; it is about one-sixth as potent as epinephrine.T1
  7. Avoid elective vasoconstrictor use with: BP over 200/115 (Malamed's cutoff), uncontrolled hyperthyroidism, MI or stroke within 6 months, unstable angina, recent CABG, uncontrolled arrhythmia, sulfite allergy, recent cocaine/methamphetamine.T1S14
  8. Epinephrine for hemostasis is used in 1:50,000 only in small amounts at a site.T1
  9. Sodium bisulfite is the antioxidant that preserves vasoconstrictors; it is the usual cause of "anesthetic allergy" reactions in sulfite-sensitive asthmatics.S14

Facts are written in our own words; each tag links to its source. Values marked "sources vary" differ between references, so check the one your program uses.