Armamentarium for Local Anesthesia and Technique – Flashcards

•Breech loading metallic cartridge type •Insert cartridge from side •Needle attached to barrel of syringe at needle adaptor •Needle penetrates barrel and punctures diaphragm of cartridge

•Tip or harpoon attached to piston •Penetrates rubber stopper •When negative pressure is exerted on thumb ring, positive aspiration will occur if needle is in a blood vessel

•Uses elasticity of stopper to obtain negative pressure needed for aspiration •Diaphragm rests on metal projection •Pressure directly on cartridge by thumb disk •Shaft distorts diaphragm producing positive pressure in cartridge; when pressure is released, negative pressure develops--permits positive aspiration if in vessel

•Pressure syringes--P D L injections •Jet Injector •Disposable syringes •Safety syringes

•Wash and rinse •Clean harpoon with brush •Autoclave •Recommended by Malamed text; Dismantle and lubricate every 5 times Replace pistons and harpoons as needed

•Stainless steel, pre-sterilized, disposable •The greater the angle of the bevel with the long axis of the needle, the greater the degree of deflection •Shank (shaft)--diameter of lumen and length •Hub--plastic or metal through which needle attaches to syringe •Syringe penetrating end--perforates rubber diaphragm

•Gauge--major factor in aspiration diameter of lumen of needle •smaller number = greater diameter •Color coded: red (25 g), yellow (27 g), blue (30 g) •Larger gauge safer--(25 gauge) less deflection, greater accuracy, less needle breakage, more reliable aspiration •More pressure needed with smaller lumen

•Long—avg. 32 mm (about 1 5/8 inches) •Short--avg. 20 mm (about 1 inch) •Do not insert to hub (weakest portion) •Long recommended for injections requiring deep tissue penetration •Typically use 25 gauge long and 27 gauge short needles •SWC needles are 25 gauge, 35 mm long 27 gauge, 25 mm short •Never use on more than one patient •Change after 3 to 4 penetrations •Cover when not used—"snap" cover on securely •Make needle "safe" immediately after injection •Scoop technique for re-capping •Alternatively, use cotton pliers or other "gadget" which allows one-handed technique •Dispose of properly in Sharp's containers

•Pain on insertion--dull needle, prevent by changing needle, using topical anesthetic •Breakage--do not bend or insert to hub, do not change directions within tissues (documented breakage usually has occurred with 30 gauge needles) •Pain on withdrawal--barbs from hitting bone or during manufacturing •Injury to patient or operator--carelessness, inattention, or sudden movement

•Be aware of location of needle tip ALWAYS •Do not wear loupes while handling needles and during local anesthesia •Re-cap with one-handed technique •This cannot be emphasized enough!!

•Pre-filled with anesthetic solution •1.8 ml (labeling considerations to be discussed)** •Cylindrical glass tube •Stopper (black, indented from end of tube) •Aluminum cap •Diaphragm (latex—no allergies reported) •Thin plastic label •Color band indicates specific drug: •Red—2% Lidocaine with 1:100,000 epinephrine •Tan—3% Mepivacaine plain (no epinephrine)

•Quantity of local anesthetic drug—MEMORIZE!! •2% has 20 mg of anesthetic per ml •2% has 20 mg times 1.8 ml = 36 mg per cartridge •3% has 30 mg of anesthetic per ml •3% has 30 mg times 1.8 ml or = 54 mg per cartridge •4% has 40 mg of anesthetic per ml •4% has 40 mg times 1.8 ml or = 72 mg per cartridge

•Note type and concentration •Epinephrine 1:100,000 •10 micrograms per milliliter •10 times 1.8 = 18 micrograms per cartridge •Lowers pH resulting in: •Slower onset of action •Increase in burning sensation

•Sodium bisulfite (preservative for vasopressor/antioxidant, lowers pH) •Sodium chloride (makes isotonic) •Distilled water (diluent) •Silicone (no longer use methylparaben)

•Vacuum sealed containers--50 cartridges •Boxes of 100 in blister packs of 10 •Store in original container, room temperature, dark •No need to soak in disinfectant •Cartridge warmers not necessary, and may destroy vasopressor, burn

•Large bubbles--nitrogen gas or contaminants •Extruded stopper--frozen or prolonged storage in alcohol •Burning on injection--pH or contaminants •Sticky stopper •Corrosion--immersion in disinfectant •Rust or dents--leakage •Leaking during injection--if cartridge placed in syringe after needle •Broken cartridges--shipping damage (check by neck or stopper), excessive force to engage harpoon, bent harpoon •Do not use past expiration date •NEVER USE A CARTRIDGE ON MORE THAN 1 PATIENT

•Topical anesthetic—apply 2 to 3 minutes •Benzocaine 20% (ester)--safer •Lidocaine 5% (amide) •***remember to document use •Applicator sticks •Gauze •Hemostat/cotton pliers •Mouth mirror •Saliva ejector •Air/water syringe

•Remove syringe from container •Retract piston •Insert cartridge, rubber end first •Engage harpoon with gentle finger pressure •Attach needle, remove plastic cap from syringe end: do not put finger on end of needle as seen on page 125, figure 9-6 •Carefully remove protective cap •Expel a few drops of anesthetic

•Recap using "scoop"technique •Unload by retracting piston until harpoon disengages •Remove cartridge by letting it fall free—be sure rubber stopper is no longer connected to harpoon •Unscrew capped needle—do not remove/discard metal needle adaptor •Discard only EMPTYcartridges in Sharp's container •If cartridge has any remaining solution in it—before removing and discarding it, expel the solution into gauze in salsa cup (new protocol as of 2/2010 at SWC)****

•Preferred technique-- Recap, remove needle, retract piston, remove used cartridge, insert new cartridge, embed harpoon, reattach needle

•Use a sterilized sharp needle •Check the flow of anesthetic solution •Position the patient •Identify and palpate landmarks •Dry the tissue •Apply topical anesthetic for 2 minutes •Suction and create clear field prior to injection •Communicate with patient •Establish a firm hand rest—notice palm position to allow for closer access to face •Make tissue taut; use gauze for every injection (except palatal) to help retract and avoid slippage •Keep syringe out of patient's sight •Pay attention to end of needle location •Insert needle into mucosa, bevel toward bone •Watch and communicate with patient •Slowly advance needle toward target •Deposit several drops of anesthetic--optional •Aspirate (any blood is positive must change cartridge and needle) •Slowly deposit local anesthetic solution (re-aspirate several times during injection—avoids intravascular injection of large volume of solution) •Communicate with patient •Slowly withdraw syringe •Recap firmly •Rinse and suction patient's mouth •Observe patient and record in chart

•Leakage •Broken cartridges •Bent harpoon •Disengagement of harpoon during aspiration •Surface deposits •Size for hand