Local Anesthetics Flashcards
What is the AHA guidelines regarding max amount of Epinephrine for a healthy patient and cardiovascular disease pt?
EPINEPHRINE max
Local Anesthetics block nerve conduction by?
🚫⬆️🚪
Preventing an 🚫⬆️ increase in permeability to NA+
Local Anesthetics are SODIUM CHANNEL BLOCKERS 🚪
PAIN signals to be transduced REQUIRES DEPOLARIZATION from an influx of NA+ ions through these exact channels
What is Levonordefrin
“IM PC”
LEVONORDEFRIN
- TOPICAL NASAL DECONGESTANT
- VASOCONSTRICTOR , most often used in dentistry.
.05mg/ml in most anesthetic
- 2% Polocaine
- 2% Carbocaine
- 2% Isocaine
- 2% Mepivacaine
“IM PC”
What is the difference between Epinephrine and Levonordefrine?
The TWO vasoconstrictors that are available in the U.S. are epinephrine and levonordefrin.
LEVONORDEFRIN s ONE-SIXTH as potent as epinephrine and is only available in 2% MEPIVOCAINE and 1:20,000 levonordefrin. It provides significantly LESS HEMOSTASIS than epinephrine and therefore is less useful for NSPT. (nonsurgical periodontal therapy)
Levonordefrin is absolutely CONTRAINDICATED in patients who are taking TRICYCLIC ANTIDEPRESSANTS.
LIDOCAINE 2% 1:100,000 EPI
ONSET PULPAL DURATION SOFT TISSUE DURATION MG/KG MAX DOSAGE
LIDOCAINE 2% 1:100:000 WITH EPI
O: 2-3 minutes
P: 60 minutes Max Inf / 85 min Mand Block
ST: 3-5 hours
Mg/Kg : 4.4
Max: 300 mg
Articaine 4% 1:100,000 EPI
ONSET PULPAL DURATION SOFT TISSUE DURATION MG/KG MAX DOSAGE
ARTICAINE 4% 1:100:000 WITH EPI
O: 1-2 minutes
P: 60-75 minutes max inf / 90 mand block
ST: 3-6 hours
Mg/Kg: 7
Max: 500
Articaine 4% 1:200,000 EPI
ONSET
PULPAL DURATION
SOFT TISSUE DURATION
ARTICAINE 4% 1:200:000 WITH EPI
O: 1-2 minutes
P: 45-60 minutes
ST: 2-5 hours
EPINEPHRINE in Local Anesthetics
Role? 🐢
What condition is it contraindicated?
Vasoconstrictor
⬇️ reduces toxicity by slooowing 🐢 rate of absorption of local anesthetic into CV system
Contraindicated in HYPERTHYROIDISM
- The elevated levels of thyroid hormones in these patients make them extremely sensitive to sympathomimetic drugs such as epinephrine
- AURICULAR FIBRILLATION is the most frequent cardiac arrhythmia in hyperthyroidism
What preservative is used in local anesthetic with epinephrine / levonordefrin?
SODIUM BISULPHITE
Sulfites are preservatives used in some drinks, foods and medications. Sulfites can cause ALLERGY LIKE reactions (intolerances), with symptoms such as wheezing in people with asthma, allergic rhinitis (hay fever), and urticaria (hives).
Because their names are similar, people often confuse sulfa with sulfites. Sulfites occur naturally in most wines. They’re also used as a preservative in other foods. SULFITES and SULFA medications are chemically UNRELATED.
What is the Rule of 25?
You can use 1 Carpule of any marketed local anesthetic for every 25 pounds of body weight.
When would 3% Mepivacaine be the appropriate choice for local anesthetic?
Cardiovascular disease
Hyperthyroidism
Allergy to Sodium Bisulphate
Local Anesthetic Toxicity
Causes?
Signs?
⬆️
Causation:
- Excess Dosage
- Inadvertent intravascular injection at rapid rate
Signs: BIPHASIC (two phases) Lidocaine toxicity (and all local anesthetic toxicity) can cause -
Early Phase:
- Circumoral numbness
- Dizziness
- Tinnitis
- ⬆️ increased heart rate (tachycardia)and BP
- Facial tingling
- Restlessness
- Vertigo
Later Phase:
- Drowsiness
- Slurred speech
- Tonic-clonic seizures.
- Loss of Consciousness
- Cardiovascular collapse
Local anesthetics are actually CNS depressants, thus tonic-clonic seizures are thought to be caused by depression of inhibitory pathways.
Local Anesthetic Nerve Blocks in children
- 4.4 mg/kg is maximum recommended dose of anesthetic
- IAN innervates all lower teeth
- PSA innervates all upper Primary molars
- ASA innervates upper Primary anteriors
