Unit 6 Flashcards
what 3 components do we need for anesthetic armamentarium
- aspirating syringe
- disposable sterile needle
- single-dose anesthetic cartridge
what supplemental armamentarium is needed for anesthetic application
- topical antiseptic (optional)
- topical anesthetic
- applicator sticks
- gauze
- hemostat or cotton pliers
- needle capping aid
what is the advantage and purpose of the harpoon
- to provide negative pressure inside the anesthetic cartridge when the thumb ring is pulled back by the clinician. this causes retraction of the rubber stopper
- assuming the needle has an adequate gauge, blood will enter the cartridge following the negative pressure exerted on the thumb right, thus signalling the clinician that a positive aspiration has occurred (don’t want this – need to see negative aspiration before depositing anesthetic)
what is a breech-loading metallic cartridge type
- reusable syringe
- most commonly used syringe type today
- harpoon = aspirating
- needle attached to barrel of syringe at the needle adapter
- end of needle penetrates barrel of syringe and pierces rubber diaphragm on the cartridge
- aspirating tip or harpoon used to penetrate thicker rubber stopper
- when negative pressure is exerted on the thumb ring, blood will enter the needle lumen and cartridge if in blood vessel
what are the advantages to using a reusable breech-loading metallic syringe type
- readily visible cartridge
- ease of aspiration with one hand
- autoclavable
- rust resistant
- long lasting with proper maintenance
what are the disadvantages to using a reusable breech-loading metallic syringe type
- weight (heavy)
- size – may be too big for small hands
- possibility of infection with improper care
what is a breech-loading metallic cartridge self-aspirating
- obtains negative pressure for aspiration by means of the elasticity of the rubber diaphragm of the cartridge
- the diaphragm rests on a metal projection inside the syringe which directs the needle into the cartridge
- pressure acting directly through the plunger shaft stretches the rubber diaphragm
- when pressure is released, sufficient negative pressure is produced within the cartridge to achieve aspiration
which of the 2 methods of aspiration produces twice as much negative pressure compared to the other
- the thumb ring
which of the 2 methods of aspiration permits easy, multiple aspirations throughout the period of local anesthetic deposition
- the self aspirating
- highly recommended
what are the advantages to using a breech-loading metallic cartridge type, self aspirating syringe
- readily visible cartridge
- ease of aspiration with small hands
- disengagement of harpoon from rubber stopper cannot occur
- autoclavable
- rust resistant
- long lasting
what are the disadvantages to using a breech-loading metallic cartridge type, self aspirating syringe
- weight (heavy)
- feeling of insecurity for those used to the harpoon
- possibility of infection with improper care
what is a pressure-type syringe
- aka intraligamentary syringe
- introduced in the late 1970s
- used for periodontal ligament injections
what 4 things can we do to care for syringes properly
- thorough cleaning and sterilization, then autoclave
- periodically dismantled and lubricated with a light oil (every 5 uses)
- replace piston and harpoon as needed
- clean the harpoon with a brush after each use
what kind of problems can we run into with syringes
- leakage during injection
- cartridge breakage
- bent harpoon
- disengagement of harpoon from plunger during aspiration
- surface deposits
what can occur to cause leakage during injection
- when reloading a syringe with a second cartridge, and the needle is already in place, one should be sure that the needle penetrates the centre of the rubber diaphragm
- an off center perforation will produce an overall puncture of the diaphragm that permits leakage of the anesthetic solution around the outside of the metal needle and into pt’s mouth
what can occur to cause a cartridge breakage
- a badly worn syringe may damage the cartridge, leading to breakage
- this can also result from a bent harpoon
- a needle that is bent at its proximal end, not perforating the diaphragm on the cartridge, can be a problem
- positive pressure on the thumb ring increase intracartridge pressure which can lead to cartridge breakage
what can happen if we have a bent harpoon
- the harpoon must be straight and sharp
- a bent harpoon produces an off center puncture of the rubber plunger causing the plunger to rotate as it moves down the glass cartridge
- this may occasionally result in cartridge breakage
what can cause disengagement of the harpoon from the plunger during aspiration
- occurs if the harpoon is dull or if administrator applies too much pressure to the thumb ring during aspiration
- harpoon should be cleaned and sharpened or replaced
how can we deal with surface deposits
- accumulations of debris, saliva, and disinfectant solutions interfere with syringe function and appearance
- deposits resembling rust can be removed with thorough scrubbing
- ultrasonic cleaning will not harm syringes
what is the bevel
- point or tip of the needle
- defined by manufacturer as long, medium or short
- the greater the angle of the bevel with the long axis of the needle, the greater the deflection as needle is passed through soft tissue
what is the shank
- aka the shaft
- consists of the diameter of the needle lumen (needle gauge) and the length of the shank from the point to the hub