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125 Cards in this Set

  • Front
  • Back
Anatomical considerations for Pediatric patients receiving anesthesia
-Bone density is less
-Mandibular foramen located more inferiorily
Behavior management for pediatric patients
-Use of topical anesthetic
-Counter irritation
-Assistant to hold hands and stabilize
-cradle the head when posible
-use mouth prop when it is essential to have mouth open or with patients you do not know
-young children have a limited ability to inform about anesthesia
What should you do while giving anesthesia to children??
Children often become upset over the feeling of numbness....
-let them see themselves. they may feel distorted
-tell the child when the feeling of numbness (big, tingly, sparkly etc) will go away. Use terms the child will understand
technique tips
-slow deposition of solution (not too slow)
-use 27 gauge needle
-maxillary short (1")
-mandibular long (1 5/8") usuallly inferior alveolar block & long buccal injection
- may use mouth prop ('tooth pillow")
-reflect lip and pull tissue tight
-finger rests
complications of local anesthesia
-biting of lip, cheek, tongue or excessive rubbing
-Over dose
Dosage of Local anesthetic
2 year old = 20 lb = 1 carpule 40 mg
4.5 year old = 40 lb = 2 carpule 80 mg
8 year old= 60lb = 3 carpule 120 mg
duration of anesthesia
-consider shorter duration of anesthesia
-3% mepivacain 20-40 min pulpal anesthesia and 1-3 hr soft tissue anesthesia
-2% lidocaine 1:100,000 epi 1-2.5 hr pulpal anesthesia and 2-5 hr soft tissue anesthesia
-3% mepivacaine = 20 min Maxillary and 40 min mandibular
Short acting local anesthetic
-consider 3% mepivacaine (carbocaine) when the procedure is
-very short
-expected to have little post op pain
-done for patients who are at high risk to bite their lips or tongue
Articaine (Septocaine)
-4% articaine
-1:100,000 epinephrine
-be careful about dose-higher concentration of drug
-not approved for use in children under 4 years
Local Anesthesia complications: LOCAL
-needle breakage
-pain on injection
-persistent anesthesia or parasthesia
-sloughing of tissues
-soft tissue injuries
-facial nerve paralysis
-postanesthesia intraoral lesions
Local Anesthesia Complications: SYSTEMIC
Needle Breakage
-extremely rare with disposable needles
-causes: smaller needles, bent needles, manufacture's defect
-problem: scar tissue, migration (generally posteriorily), infection
-prevention: longer, larger needles, don't insert to hub, don't redirect while needle is deep (more than 1cm into tissues)
Needle breakage management
-instruct the patient not to move
-keep the mouth open (bite block)
-if you can see it, grab it (hemostat)
-if you can't see it, refer to OMS immediately, inform patient, document incident, keep needle stump
-litigation? call your lawyer
Causes of Pain on injection
-careless technique, callous attitude
-dull needles
-rapid injection
-needles become barbed after contacting bone
Problems with pain on injection
-pain--> anxiety---> medical emergency
-pain --> sudden movement--> needle breakage
Prevention of Pain on injection
-proper techniques
-sharp needles
-topical anesthetic
-sterile local anesthetic solution
-inject slowly
-anesthetic solution too hot or too cold (room temperature is good)
Burning on injection Causes
-solution pH (5,3)
-rapid injection
-contamination (sterilizing solutions)
-carpule warmed to body temp is "too hot"
Problem burning on injection
-related to pH: transient
-related to others: possible tissue damage
Prevention and Management of Burnign on injection
-slow injection (ideally 1cc/min)
-don't store carpules in alcohol or other sterilizing agent
-follow up
-manage specific problem
Persistent Anesthesia or Parasthesia Causes
-contaminated anesthetic solution
-needle trauma to nerve ('electric shock")
-hematoma --> pressure
Persistent Anesthesia or Parasthesia Problems
-self-inflicted injury (biting, heat)
-hyperesthesia (normal stimuli cause an excessive sensation) or dyesthesia (normal stimuli cause pain)
Persistent Anesthesia or Parasthesia Prevention
-adherence to injection protocol
-proper care and handling or carpules
Persistent Anesthesia or Parasthesia Management
-Reassure; follow up; document in chart
-refer to OMS if still present after 2 months
-restricted jaw movement
-trauma to muscles or blood vessels: hemorrhage, multiple injections, large volume of anesthetic, infection
-contaminated anesthetic solution
-local anesthestics are slightly myotoxic
Trismus problem
-usually minor
-chronic hypomobility
Prevention of Trismus
-sharp, sterile, disposable needle
-proper handling of anesthetic carpule
-aseptic technique
-practice atraumatic insertion and injection
-avoid repeated injections; use regional blocks
-use minimum volumes
Trismus Management
-usually occurs 1-6 days after injections
-record incident and treatment in dental chart
-use heat therapy, warm saline rinses, NSAIDs, muscle relaxants (e.g. Valium)
-physical therapy (gum chewing)
-if trismus/pain continues > 2 days --> add antibiotics
-if problem worsens or if not improving after 7 days refer to OMS
Causes of Hematoma
-effusion of blood into extravascular space
-usually related to arterial injury
-related to density of tissues surrounding vessel
-PSA (most common site for hematoma, bruise visible on skin)
-IAN bruise visible only intraorally
Hematoma Problem
-trismus and pain
-swelling and discoloration usully subside in 2-3 weeks: inconvenience to patient, source of embarassment to HCP
-possible source of infection
Hematoma Prevention
-knowledge of normal anatomy in injection site
-modify injection technique as dictated by patient's anatomy
-use short needle for PSA
-minimize number of needle penetrations into tissue
-don't use a needle as a probe in tissues
Hematoma Management
-immediate- apply direct pressure for 5 minutes
-IAN-medial ramus
-Infraorbital- directly over foramen
-Mental- directly over foramen
-PSA: Ice/Pressure on face, digital pressure in mucobuccal fold as far posterior as patient will tolerate
Hematoma Subsequent
-document in patient's record
-advise patient about possible trismus, discomfort, and dicoloration (bruise)
-ice for first 2 hours
-heat after first 24 hours
-OTC meds
-Tincture of time
-extremely rare
-contaminated needle or solution
-improper technique
-injecting into an area of infection
Problem with infection
-fascial space infection
Infection Prevention
-use disposable needles
-avoid contamination of needle through contact with nosterile surfaces
-avoid multiple injections with the same needle
-proper care/handling of carpule
-store aseptically in originally ocntainer
-cleanse diaphragm with a sterile disposable alcohol wipe
-properly prepare tissues prior to penetration: dry, topical anesthetic
-swelling of tissues
-trauma during injection
-allergy: angioedema from topical anesthetic; vasodilation secondary to histamine release
-injection of irritating solution (alcohol or cold sterilizing fluid)
Edema Problem
-usually not significant
-occasionally pain and dysfunction in region
-angioneurotic edema can compromise airway
Edema Prevention
-proper care and handling of local anesthetic armamentarium
-atraumatic injection technique
-good medical evaluation of patient before treatment
Edema Management
-if from trauma or irritating solutions: usually no formal therapy maybe Rx analgesics
-If from hematoma : see hematoma
If from infection: see infection
Edema Management if from allergic reaction
in buccal tissues:
-no airway involvement
-consult with allergist
in tongue, FOM, or pharynx
-life threatening
-BLS, EMS (911)
-epinephrine (.3mg q 5 min), antihistamine, corticosteroid
Sloughing of the tissues Causes
epithelial desquamation
-prolonged application of topical anesthetic
-heightened sensitivity of tissues to local anesthetic
sterile abscess
-prolonged ischemia
-almost always in the tissues of the hard palate
Sloughing of the tissues problem
-pain (like an ulcer)
-infection (rare)
Sloughing of the tissues prevention
-topical anesthetics 1-2 minutes
-avoid concentrated vasoconstrictors
-avoid reinjection of palatal tissues
Sloughing of tissues Management
-inform/reassure patient
-document in chart
Soft tissue injury Cause
-child or mentally handicapped adult
-self-inflicted trauma to tongue, lips, or cheeks while tissues are numb
Soft tissue injury Prevention
-local anesthetic of appropriate duration
-warn the patient and guardian (self adherent warning sticker)
-cotton roll between lip and teeth
-advise patient to avoid chewing foods until numbness wears off
Soft tissue injury management
-analgesics for pain
-antibiotics if infection results (rare)
-warm NS rinses
-lubricant to cover lip lesion
Facial Nerve Paralysis Causes
-infraorbital block or maxillary canine infiltration
-anesthetic into deep lobe of parotid gland:
-too far posterior during IAN block or too deep during akinosi block
Facial nerve paralysis Problems
-transitory: several hours
-unilateral paralysis of involved muscles
-loss of protective lid reflex --> corneal irritation
Facial nerve paralysis prevention
-adhere to injection protocols
-IAN -contact with bone
-akinosi <25mm
Facial Nerve Paralysis Management
-reassure patient
-eye patch or manually close eye
-avoid contact lenses
-document in chart
Postanesthetic Intraoral Lesions
-intense pain and ulcerations at injection site approximately 2 days after intraoral anesthetic injection
-cause: activation of latent form of disease process
-recurent apthous stomatitis (probably autoimmune)
-herpes simplex virus
Postanesthetic Intraoral Lesions Problem
-pain in ulcerated areas
-secondary infection (rare)
Postanesthetic intraoral lesions prevention
-no way to prevent
-can use acyclovir in prodromal phase to minimize the acute phase of the disease process
Postanesthetic Intraoral Lesions Management
-reassure patient
-analgesics if required
-topical anesthetic preparations (viscous lidocaine, 1-2-3 mouth rinse (lidocaine, benedryl, MOM), orabase ointment, zilactin
-ulcers usually last 7-10 dyas
-document in chart
Anatomy of an Aspirating Syringe
-Thumb ring
-Finger grip
-Guide bearing
-Piston with Harpoon (harpoon most likely to break)
Types of Needle
- 25 gauge (Red)
-27 gauge (Yellow)
-30 gauge (Blue)
Needle Lengths
-Short 20mm
-Long 32mm
Needle Parts
-syringe adaptor
-bevel (should be towards nerve you are trying to anesthetize)
-cartridge penetration end
How to assemble a syringe
-place needle on syringe
-pull back on thumb ring to insert carpule into syringe
-slowly slide carpule forward to penetrate diaphragm
-Use needle puncture guard
-engage harpoon into stopper
-verify flow of local anesthetic
Atraumatic Injection Technique Part 1-7
1-use a sterilized sharp needle
2-check the flow of local anesthetic solution
3-solution at room temp
4-Position of the patient-supine if tolerated
5-Dry the tissue
6-Apply topical antiseptic (optional)
7-Apply topical anesthetic
Atraumatic Injection Technique Part 8-14
8-Communicate with the patient-explain superficial numbness, minimize discomfort
9-establish a firm hand rest
10-make the tissue taut
11-keep the syringe out of patient's sight
12-insert the needle into the mucosa-bevel towards bone
13-watch and communicate with patient-never say it wont hurt
14-inject several drops (optional)
Atraumatic injection Technique part 15-21
-Slowly advance needle towards target
slowly deposit the local anesthetic solution
-communicate with the patient-explain why you are injecting slowly
-slowly withdraw the syringe and cap the needle using safe technique
-observe the patient after the injection
-record the injection in the pt's chart
Nerves that can be blocked in maxilla
-Posterior Superior Alveolar (PSA)
-Maxillary (2nd division block)
-Greater palatine
Nerve Block Advantages
-fewer injections (pain) when anesthetizing several sites
-Less total volume of anesthetic soln and less chance of overdose
-Lasts longer and more profound
Distribution of Nerve blocks in Maxilla
Nerve Block disadvantages
-lasts longer
-Greater chance of complication(hematoma, intravascular injection, slightly lower success rate, trismus, anesthesia more wide
Structures exiting a foramen
Reasons for the bevel toward the bone
-bevel away from bone is more likely to penetrate periosteum and cause pain and bruising
-bevel towards bone prevents this
-depositing fluid that will diffuse through the periosteal and into the nerve near the end of the root
-canine root is longer and less likely to be anesthetized
-Muscle attachments can effect distribution of anesthesia
can anesthetize molars with a half a carpule
Posterior Superior Alveolar Nerve Block (PSA)
-anesthetizes maxillary 3rd, 2nd and 1st molars (MB root of 1st molar not anesthetized=28%) and buccal periodontium and facial bone
-Indications: treating >1maxillary molar, infection site, infiltration not effective
-Contraindication: risk of hemorrhage too great
-angled across 2nd molar crown
PSA Advantages
-95% success rate
-less injections when treating multiple teeth
-less total volume
PSA disadvantages
-no bony landmarks
-2nd injection usually required for 1st molar
Infraorbital Nerve Block
-Anesthetizes ASA nerve and MSA nerve
-ASA nerve: pulps of incisors and canine
-MSA nerve:72% pulp of premolars, MB root of 1st
-Infraorbital Nerve (inferior palpebral, lateral nasal superior labial)
-Facial bone and periodontium of effected teeth
Infraorbital Indication and Contraindications
-Indications: multiple teeth, infection, infiltrations not effective
-Contraindications: 1 or 2 teeth, bleeding disorders, anticoagulants
Infraorbital nerve block advantages and disadvantages
-Advantages: simple, minimal volume of solution, minimal punctures
-Disadvantages: lack of confidence in operator-fear of injury to eye, landmarks usually difficult to palpate
Infraorbital nerve block landmarks
-lower rim of the orbital
-center of the eye
Greater Palatine Nerve Block
-Anesthetizes posterior portion of hard palate and its overlying soft tissues, anteriorly as far as the 1st premolar and medially to the midline
-indications: pain control during restorative, periodontal, or oral surgical procedures
-contraindications inflammation in site, smaller area of therapy (1 or 2 teeth)
Advantages and Disadvantages of Greater Palatine Nerve Block
-Advantages: minimizes needle penetrations and volume of solution
-Disadvantages: no hemostasis except at site of injection, potentially traumatic/painful
-Alternatives: infiltration, V2 block
Target of Greater Palatine Nerve Block
-Anterior 1/2 2nd : 0%
-Posterior 1/2 2nd: 40%
-Anterior 1/2 3rd: 50%
-Posterior 1/2 3rd: 10%
Nasopalatine Nerve Block
-Anesthetizes nasopalatine nerves bilaterally anterior portion of hard palate (soft and hard tissues) from mesial of right 1st premolar to the mesial of the left 1st premolar
-Indications: restorative, periodontal, or oral surgery procedures on multiple teeth
-Contraindications: inflammation or infection in area, smaller area of therapy
Nasopalatine Nerve Block Advantages and Disadvantages
-Advantages: Fewer needle penetrations, less volume of soln
-Disadvantages: hemostasis only in area of injection, potentially the most painful intraoral injection
-Alternatives: local infiltrations, maxillary nerve (V2) block
Maxillary Nerve (V2) Block
-Anesthetizes: pulpal anesthesia in hemimaxilla, soft tissue and bone and hemimaxilla, skin of lower eyelid, side of nose, cheek, upper lip
-Indications: extensive restorative, periodontal or oral surgery procedures, inflammation or infection precluding other blocks, diagnosis or treatment of neuralias or tics of V2 nerve
Maxillary Nerve (V2) Block Contraindications
-inexperienced operator
-pediatric patient
-uncooperative patient
-inflammation or infection at injection site
-when hemorrhage is risky
-bony obstructions in canal (5-15%)
Maxillary Nerve (V2) Block Advantages and disadvantages
-Advantages: high success rate-95%
-minimizes needle penetrations (1 vs 4) and volume of anesthetic (1 vs 2 carpules)
-usually atraumatic
-Disadvantage: risk of hematoma, lack of hemostasis at surgery site, discomfort, arbitrary landmarks
-Alternatives - other blocks, infiltrations
V2 block methods
-Greater palatine canal approach to V2 block
-high tuberosity approach to V2
Inferior Alveolar nerve block general
-aka mandibular nerve block
-most commonly used
-highest rate of failure (15-20%)
-Try and avoid bilateral mandibular blocks (uncomfortable to pt)
-most difficult to master
Inferior Alveolar Nerve block
-nerves anesthetized: inferior alveolar, mental, incisive, lingual (usually)
-indications: procedures on multiple teeth in one quadrant, buccal and lingual soft tissue required
-contraindications: infection or acute inflammation, tongue or lip biters (children, mentally handicapped)
-Advantages: one injection provides a wide area of anesthesia
Inferior alveolar nerve block Disadvantages
-sometimes not necessary for localized areas/procedures
-high block failure rate
-intra-oral landmarks not consistent
-high rate of positive aspiration (10-15%)
-lingual and lip anesthesia (biters/hot beverages)
Inferior Alveolar Nerve Block Insertion and Target
-insertion: mucosa on medial aspect of mandibular ramus
-target: inferior alveolar nerve before it enters the foramen
Inferior Alveolar Nerve Block Landmarks
-coronoid notch (greatest concavity on the anterior border of the ramus)
-pterygomandibular raphe
-occlusal plane of mandibular posterior teeth (6-10 mm above occlusal plane )
Inferior Alveolar Nerve Block Failures
-deposition of anesthetic below mandibular foramen
-deposition of anesthetic too far anteriorly
-accessory innervation of mandibular teeth (mylohyoid nerve posteriorly and mylohyoid/overlapping fibers of contralateral IAN)
-bifid inferior alveolar nerve (lower indicidence)
Inferior Alveolar Complications
-hematoma (hold pressure)
-facial paralysis (anesthetic in parotid)
Inferior Alveolar Technique
-place index finger or thumb on the coronoid notch, pull tissue tight
-6-10mm above the occlusal plane of the mandible & middle of thumb determines height of injection
-the anteroposterior point of the injection is 3/4 the distance of the pterygomandibular raphe
-align the barrel of the syringe across the contralateral premolars
-come across contralateral premolars & anterior to the soft tissues
-if you touch bone, redirect around to ipsilateral canine & advance slightly into base of V formed by the pterygomandibular raphe & ramus of mandible
-penetration depth is 20-25mm, 2/3 to 3/4 length of long needle
Adjunctive Mylohyoid Block
-retract tongue to midline, then inject at the apical area of second molar on the lingual surface of the mandible
Adjunctive Contralateral Inferior Alveolar
-supraperiosteal injection technique across the midline of the anterior mandibular teeth (buccal surface)
Adjunctive Lingual Nerve Block
-deposit .1 to .2ml of anesthetic when withdrawing needle from inferior alveolar block
Inferior Alveolar Signs and Symptoms
-tingling or numbness of lip and chin to midline
-tingling or numbness of the inpsilateral anterior two thirds of the tongue
-anesthesia of teeth and gingiva ipsilaterally (except buccal nerve distribution)
Buccal Nerve Block Complications and Technique
-AKA long buccal nerve block
-anesthetizes soft tissues and periosteum buccal to the mandibular molars
-indications: buccal soft tissu anesthesia for procedures on the mandibular molars
-Contraindications: infection/inflammation in the area
-Complications: rare (hematoma)
-Technique: penetrate mucosa about 2mm contact bone, aspirate and inject
Buccal Nerve Block Advantages/Disadvantages
-advantages: easy, high, success rate
-disadvantages: potentially painful if periosteum is torn
-insertion: mucosa distal and buccal to the most posterior mandibular molar
-target: buccal nerve as it passes over the anterior border of the ramus
-landmarks: mandibular molars and mucobuccal fold
-failures: rare
Gow-Gates Block
-Aka mandibular block
-blocks entire distribution of V3
-Anesthesia of inferior alveolar, lingual, mental, incisive, mylohyoid, buccal and auriculotemporal nerves
-Difficult learning curve
-more successful than inferior alveolar block
Gow-Gates Indications/ Contraindications
-Indications: procedures on multiple teeth, soft tissue anesthesia , failed inferior alveolar block
-Contraindications: infection/inflammation, lip/tongue biters, pts who are unable to open mouth wide
Gow-Gates Block Advantages/disadvantages
-Advantages: only one injection
-high success rate (95%)
-minimal complications
-successful anesthesia of bifid -inferior alveolar nerves, -Disadvantages: tongue/lip anesthesia,-longer time to onset of anesthesia, higher learning curve
Gow Gates Block Insertion/Target
-insertion: mucosa on the mesial of ramus in line of tragus and commissure distal to the maxillary second molar
-Target (lateral surface of condylar neck, below insertion of lateral pterygoid
-landmarks: tragus and commissure, just below mesiopalatal cusp of the maxillary second molar
Gow Gates Complications
-hematoma (rare)
-trismus (rare)
-paralysis of cranial nerve III, IV, VI (eye paralysis diplopia)
Gow-Gates Technique
-have pt open wide, point of insertion below mesiopalatal cusp of maxillary second molar aiming to tragus of ear (considerably higher than occlusal plane)
-advance needle 20-25mm until bone is contracted aspirate and injection
-have pt stay open 1-2min after injection
Akinosi Block
-aka closed mouth block
-useful when dental therapy required in pts with limited mouth opening (trismus)
Akinosi Block Indications/contraindications
Indications: limited mouth opening,inability to visualize landmarks for conventional block
Contraindications: infection or acute inflammation, lip/tongue biters, inability to gain access to the lingual aspect of ramus
Akinosi Block disadvantages and insertion
-disadvantages: difficult to visualize path of needle and depth of insertion , no bone contact
-Insertion: soft tissue overlying medial border of ramus adjacent to maxillary tuberosity at the mucogingival junction height
Akinosi Target/Landmarks
-soft tissue of the medial ramus (below Gow-Gatesand above inferior alveolar block)
-Landmarks: mucoginigval junction of maxillary (second/third molar), maxillary tuberosity/coronoid notch
Akinosi Block Failures/complications
-must stay in line with flare of the mandible or injection will be too lateral, needle insertion too low, under/overinsertion of the needle
-Complications: hematoma/trismus, facial nerve paralysis (overinsertion into parotid gland)
Akinosi Block Technique
-bevel of needle away from bone
-advance needle 25mm
Mental/Incisive Block
-the mental nerve leaves the mental foramen and provides sensory innervation to the lip and chin area
- incisive nerve continues forward to provide sensory innervation to anterior mandibular teeth
-both have limited usefullness on a routine basis for dental therapy
Mental block indications/contraindications
-Indications: buccal soft tissue anesthesia for procedures anterior to the mental foramen (biopsy)
-Contraindications: inflammation and infection in the areas
Mental Nerve Advantages/Disadvantages/Failures
-Advantages: high success rate, easy/atraumatic
-Disadvantages: hematoma (5%)
-Failures: rare, miss the foramen
Mental Block Insertion/Target/Landmarks
-Insertion: mucobuccal fold anterior to foramen
-Target: mental nerve as it exits the mental foramen
-landmarks: mandibular premolars, mucobuccal fold
Mental block Complications
-complications: hematoma
-Technique: locate foramen with finger in mucobuccal fold, insert needle anterior to foramen (5mm), aspirate and inject
Incisive Nerve Block Indications/contraindications
-dental procedures which require pulpal anesthesia of the mandibular anterior teeth, used instead of bilateral inferior alveolar blocks for treatment limited to the anterior mandible
-Contraindications: inflammation or infection
Incisive Nerve Block Advantages/Disadvantages
-advantages: pulpal anesthesia of the anterior mandibular teeth without lingual anesthesia (uncomfortable), high success rate
-Disadvantages: no lingual anesthesia, cross innervation from contralateral inferior alveolar nerve may require additional supraperiosteal injections for pulpal anesthesia
Incisive Nerve Insertion/Target/landmarks
-insertion:mucobuccal fold anterior to mucobuccal fold
-target: mental foramen (incisive nerve lies in this)
-Landmarks: mandibular premolars, mucobuccal fold
Incisive Nerve Failure/Complications
-failure: inadequate volume of anesthetic, inadequate pressure after injection
-Complications: rare, hematoma
Incisive Nerve Technique
-same as for mental block
-hold pressure for two minutes after injection to force anesthetic into the foramen and reach the incisive nerve
Mandibular Infiltration
-useful for supplemental anesthesia of anterior mandibular teeth when getting crossover fibers from contralateral inferior alveolar nerve
-thin cortical plate allows for supraperiosteal injection technique to be successful for mandibular incisors only in most pts
-technique exactly the same as for maxillary teeth with deposition of anesthetic at root apex to block dental plexus
Injection Pearls
-always recap needle after injection
-be confident
-understand the anatomy
-always use a finger rest for stabilization
-if pt complains of an electric shock after the needle is positioned, re-position the needle as you are likely in the nerve itself