Download Local Anesthesia Test 1 Study Guide Questions And Answers With Latest Quiz and more Exams Nursing in PDF only on Docsity! Local Anesthesia Test 1 Study Guide Questions And Answers With Latest Quiz Describe dissociation content ANS Determines the portion of administered anesthetic dose in the lipid soluble state (RN) Dendrite zone: ANS Area of synapses Myelination: ANS Covering on nerve membrane Impulse: ANS Ionic activity on nerve membrane Schwann Cells: ANS Forms Myelin layer Ion Channels: ANS Passage through nerve membrane Fasciculi: ANS A bundle of nerve fibers Depolarization: ANS Firing threshold is reached (-55 to -50 mV) Node of Ranvier: ANS Gap in sheath Hydrophilic: ANS Water loving Repolarization: ANS Return to resting potential (-70 mV) Which form(s) of a local anesthetic molecule is responsible for penetrating the nerve membranes? ANS Neutral base Describe the intermediate chain of local anesthetics ANS -Provides major pathways of biotransformation -Provides spacing between an aromatic (lipophilic) end and a secondary or tertiary (hydrophilic) end. -Contains a nitrogen atom in amides Which of the following local anesthetics have the longest duration of action? ANS Bupivacaine What factor influences the shift of the neutral base form (RN) of the local anesthetic molecule to the cation form (RNH) within the axoplasm? ANS H+ ions are sufficiently available in the axoplasm at a pH of 7.4 Is psychogenic pain organic in nature? ANS No, it's more psychological than physical Which of the following is NOT a desirable characteristic of local anesthetic drugs? 1. Not irritating to mucous membrane 2. Distributed easily 3. Non toxic to neutral structures 4. Easily metabolized and eliminated ANS Distributed easily Where is Articaine metabolized? ANS Both plasma and liver Where is Lidocaine metabolized? ANS Liver Which of the following topical anesthetics is classified as an amide? 1. Benzocaine 2. Tetracaine 3. Cetacaine Upon injection of a local anesthetic containing a vasoconstrictor all of the following situations occur except one......... Which one is the *Exception*? 1. Slow absorption of the anesthetic into the bloodstream 2. Decreased blood flow to the injection site 3. Decreased bleeding at the injection site 4. Decreased duration of anesthesia ANS Decreased duration of anesthesia Which of the following ARE reasons that inflammation interferes with local anesthetics? ANS - The anesthetic gets diluted from the edematous tissue -Inflamed tissue inhibits the movement of the anesthetic across the neuronal membrane -The increased inflammation causes the tissue to be more vascular which can lead to the anesthetic having more access into the bloodstream and ineffective What is the mechanism of action for Lidocaine? ANS Blocks sodium channel According to Malamed, what is the typical duration of pulpal anesthesia for 2% lidocaine w/ 1:100,000? ANS 1 hour Ester type local anesthetic drugs undergo bio-transformation in the ANS Blood by pseudocholinesterase What is the name of the most potent ester topical anesthetic? ANS Tetracaine Hydrochloride T/F: Gingival health can affect the duration of action of a local anesthetic. Inflamed tissue at the site of the injection results in a shorter duration of anesthesia. ANS Both statements are true T/F: Local anesthetic molecules work by competing with Ca++ ions to bind to these ion channels during slow depolarization and close off(block) these channels. ANS True Which of the following local anesthetics is metabolized in the plasma? 1. Procaine 2. Lidocaine 3. Mepivacaine 4. Bupivacaine ANS Procaine As a rule, topical anesthetic agents... ANS ...are used in greater concentration than injectable anesthetics Why should the clinician avoid administering local anesthetics to both the right and left mandibular quadrants during a single treatment? ANS To prevent inability of patient to control his/her mandible Infiltration is not as effective in the mandible compared to the maxilla because ANS Mandibular cortical bone is denser Numbness of the anterior 2/3 of the tongue is due to which nerve being anesthetized? ANS Lingual Upon reviewing the medical history, you learn that your patient has "atypical pseudo-cholinesterase." How does this affect your decision to use local anesthetic? ANS The patient may not be able to tolerate Ester local anesthetics Which cranial nerve provides sensory innervation to the periodontium of the maxillary teeth? ANS Trigeminal Name the nerve that provides sensory innervation to the palatal tissue of teeth # 6-11. ANS Nasopalatine What can the clinician do to prevent an emergency situation from occurring while administering local anesthesia? ANS -Provide effective communication -Offer psychological support -Do a thorough patient assessment Extruded stoppers in an anesthetic cartridge indicate that... ANS The anesthetic has been frozen The PSA injection is considered a... (infiltration or nerve block?) ANS Nerve block When do you aspirate? ANS BEFORE depositing solution The lingual nerve provides innervation to which of the following structures? ANS The gingiva on the lingual of the mandible, the anterior 2/3 of the tongue, and the mucous membrane of the floor of the mouth. What is the absolute MRD of 2% Lidocaine with 1:100,000 Epinephrine for a medically compromised patient with cardiovascular disease? ANS 2 cartridges (reference cardiac MRD .04) All of the following describe why aspiration is a necessary part of administering local anesthesia: ANS -To ensure the needle has not entered a blood vessel -To dramatically decrease the incidence of an intravascular injection (Patient comfort is not a factor) If you are scaling and root planing teeth #2-5, which injection would you use? ANS Right PSA, MSA, Greater palatine block What is pain *reaction*? ANS Personal interpretation and responses to the pain message that is highly variable among individuals Epinephrine is not to exceed *0.04 mg* per appointment for patients who... ANS -Are taking non-selective beta blockers -Are taking tricyclic antidepressants -Have cardiovascular disease How should the RDH aspirate for PSA block? ANS Aspirate, rotate, aspirate What should be avoided for patients taking tricyclic antidepressants? ANS Levonordefrin and norepinephrine. - epinephrine should be administered at the lowest effective dose...similar to cardiovascular patients What is an absolute contraindication for patients with asthma? ANS Bisulfite within vasoconstrictor Is hyperthyroidism a relative contraindication or an absolute contraindication to vasoconstrictors (epinephrine)? ANS Absolute contraindication What is the most common medical emergency when it comes to local anesthesia? ANS Vasodepressor syncope What is the most common way for needle breakage? ANS Sudden, unexpected movement of the patient (do not insert all the way to the hub) When experiencing the local complication of *hematoma*, what should be done for the patient? ANS Apply *ice* to the region at the time of the incident When a patient is experiencing the local complication of *trismus*, what should be done for the patient? ANS Apply *heat* to the area and do jaw exercises Which anesthetic agents may produce *methemoglobinemia*? ANS Prilocaine and possibly topical benzocaine What is the active ingredient of OraVerse that competes for the receptor sites of the vasoconstrictor, thus encouraging faster metabolic reuptake of the local anesthetic due to the increased vasodilatation? (used with lidocaine) ANS Phentolamine mesylate How should the RDH manage local anesthetic overdose? ANS -Terminate procedure. -Reassure patient. -Position patient in comfortable position. -Administer oxygen. -Monitor vital signs. -Summon medical assistance if needed. -Allow patient to recover and discharge. What is the major sign of an epinephrine overdose? ANS Throbbing headache What is the generic name for Benadryl? ANS diphenhydramine HCl What is the generic name for Valium? ANS Diazepam What is an example of an "exacerbation of a latent condition"? ANS A history of *herpetic cold sores* that have potential for symptoms including herpetic lesions at the sight of the injection after delivery of local anesthetic What is a common response to the anesthetic for some patients? ANS Burning sensation Injectable local anesthetics have a __________ component ANS lipophilic What is the absolute refractory period? ANS When an AP cannot occur regardless of the stimulus strength What is the MRD of epinephrine for a cardiac patient? ANS 0.04 mg What is the MRD of Levenodorfrin for a cardiac patient? ANS 0.2 mg Which side of the needle should always be toward the bone? ANS Bevel Which window should always be toward the operator? ANS Large window The smaller the gauge number... ANS ...the larger the diameter of the needle List the different needle sizes from largest to smallest ANS - 25 gauge long (red) - 27 gauge long (yellow) - 27 gauge short (orange) - 30 gauge short (blue) - 30 gauge X short (purple) How often should you change the needle for the same patient? ANS After 3 or 4 injections About how many mL is a rubber stopper in a cartridge? ANS 0.2 mL How many mL is a total cartridge? ANS 1.8 mL Which needle size is not often used (or necessary) in dentistry? ANS 30 gauge needles What is the MRD of epinephrine for a healthy patient? ANS 0.2 mg Summary of Long Buccal injection: ANS *Teeth*: NONE *Periodontium*: All periodontium buccal to molars *Needle*: 25-27 gauge long *Target*: Distal/buccal to last molar *Depth*: <4 mm (usually 1-2 mm) *Angle*: Syringe parallel to occlusal plane *Dose*: 0.2-0.3 ml Summary of Mental Block injection: ANS *Teeth*: Premolars, canines, incisors *Periodontium*: Buccal mucous membrane and bone from 2nd premolars to midline, Lower lip, Skin of chin *Needle*: 27 gauge short *Target*: Mental foramen *Depth*: 5-6 mm *Angle*: 20 degrees *Dose*: 0.6-0.9 ml Lidocaine (mg/lb) ANS 3.2 (500 mg MRD) Mepivacaine (mg/lb) ANS 3.0 (400 mg MRD) Prilocaine (mg/lb) ANS 4.0 (600 mg MRD) Articaine (mg/lb) ANS 3.2 (MRD none listed) Bupivacaine (mg/lb) ANS 0.9 (90 mg MRD) What percent of people do *not* have the MSA nerve? ANS 72% Which local injection has the highest probability of a positive aspiration? ANS Inferior Alveolar injection