Mod 4: Local Anaesthetic Adverse Effects Flashcards
Appropriate Injection technique is required to maximize pt comfort during an injection and involves what?
- Tightly stretching skin at injection site
- Inject needle perpendicular to skin
- Rapid insertion of needle through skin
- Injecting solution slowly
- Using smallest yet effective volume
Appropriate equipment to be used to maximize pt comfort, this should be?
Highest gauge needle and smallest syringe possible for particular clinical situation.
Name 2 topical agents that may reduce pt discomfort during injection?
EMLA, ELA-max creams also ethyl chloride (cold spray) may be used
The addition of Bicarbonate to LA’s can be useful in reducing pt discomfort how? and in what quantity?
By increasing the LA’s pH closer to physiological pH may reduce pain at injection site. 1cc of bicarbonate to 10cc of drug for Lidacaine, 0.1cc per 10cc of bupivicaine
The closer to what temperature reduces pain of injection?
Body temperature 37 degrees C
How can a pt be distracted in order to reduce pain of injection?
- Talking to them.
2. Allowing pt to listen to music
Local adverse reactions can occur with LA’s, Name them.
- Nerve damage
- Tendon damage
- Vessel damage
- Tourniquet effect
- Broken needle
- Infection
- Intravascular Injection
Name the 3 systemic adverse reactions.
- Systemic Toxicity reactions
- Hypersensitivity reactions
- Vasovagal reactions
Systemic Toxicity has 2 stages, early and late, which present differently, how?
In early stage the CNS stimulation is apparent - restlessness, excitability.
In later stage the CNS depression is noted - dizziness, oral numbness, confusion, tinnitus, double vision, tremors, muscle twitching, convulsions, seizure, coma, respiratory collapse.
The leads to CVS depression - decreased myocardial contractability, bradycardia reducing output and hypottension
Prevention of systemic toxicity reactions involves?
- Avoid IV injection (aspiration)
- Assess liver function
- Calculate MSD
- Be aware of current Meds.
What enzyme is responsible for metabolizing LA?
Cytochrome P4503A4 enzyme
Specific Inhibitors of amide LA metabolism include?
Itraconazole, Ketoconazole (azole antifungals)
Erythromycin, clarythromycon, cyclosporin (macrolides)
Amprenavir, Indinavir, Nelfinavir, Ritonavir (HIV protease inhibitors)
Diltiezam, Mibefradil (calcium channel blockers)
Describe the treatment protocol for Systemic toxicity.
- Stop injection, withdraw allergen, reassure pt
- Activate emergency plan
- Time check determine if 911 assistance is required
- Maintain/establish airway
- O2 10l/min
- CPR if needed
- Tourniquet above injection site
- Convulsions - Valium 10mg PO or 5mg IV
- Establish IV
- Hypotension - Ephidrine 0.5mg IM or IV
- CV collapse - Atropine 0.4mg IV
- Document after incident or transfer.
Are allergic reactions more prevalent in ester’s or amide’s?
Esters
What is responsible for most LA allergies?
PABA