vasc access & feeding tubes (Lanaux) Flashcards
Meds with > 600 mOsm
- should only be admined through central line
- total parenteral nutrition
- CRI dextrose > 5%
*meds < 600 mOsm can give in peripheral vein
Poiseuille’s law
- radius4 big variable in determing flow of something
Which will cause greatest decrease in flow through a catheter?
TQ
a. doubling diameter of catheter
b. halving diameter of the catheter
c. doubling the length of the catheter
d. halving the length of the cath
b. halving diameter of catheter
Sites of access
- cephalic vein
- lateral and medial saphenous veins
- jugular vein
- auricular veins (Dog)
central line placement
sites of access
- Jugular vein
- Medial and lateral saphenous veins
*PIC lines
Types of catheters
- Winged or Butterfly needle
- SQ fluids
- short term admin
- blood draws
- Over-the-needle
- normal ones
- Through-the-needle
- push pops
- single or multilumen
- long terms
Complications catheterization
- Phlebitis
- inflammation of vessel wall
- from endothelial lining damage
- CS
- swelling
- tenderness
- erythema over vessel
- mech damage
- admin of hyperosmotic fluids
- infection
- Thrombosis
- Catheter embolism
- Fragment of cath breaks off and enters circulation
- SQ fluid infiltration into tissue
- backed out
- upstream venous thrombosis
- Infection
- local cellulitis/phlebitis
- systemic
- Hemorrhage
Placement of peripheral catheters
- shave, aseptic scrub
- occlude vein upstream
- insert bevel up 15 deg angle
- after flash advance 1-4 mm more
- advance cath off needle
- cap, flush
- secure
Facilitative incision/relief hole
- small incision through tough skin
- # 11 scalpel blade
- cutting edge of 20 guage needle
- prevents flaring of cath tip
Venous cut down
- aseptic prep, local anesthetic
- NOT IV
- 1-2 cm skin incision parallel to vein
- Dissect out vein and isolate w/ hemostats/suture
- place cath directly through superficial vessel wall
Central venous cath
- Terminate in cranial/caudal vena cava
- Uses
- hemodynamic monitoring (CVP)
- admin meds and fluids
- seriel blood sampling
- allows longer term venous access
- Maintenance
- inc severity of complications
- aseptic technique
- foreign material
- infectious agents
- Open air ports => air embolism
- one-way locking valves to cap ports
- Inadvertent disconnections => hemorrhage
Seldinger technique
- Use smaller introducing cath/trochar and guidwire
- Can be used to replace existing cath in same location
- Technique
- Clip and aseptic prep
- drape using sterile technique
- surgeon/assistants wear sterile gloves, gown, cap, mask
- relief incision with scalpel
- cath wtih short over needle cath
- guidewire threaded through over needle cath
- J-tip protects against puncture
- always hold guidwire
- remover over needle cath, stabilize guidewire
- vessel dilate used over guidewire
- large bore cath threaded onto guidewire, advance into dilated vessel
- guidewire removed, aspirate larger cath to remove air, flush and secure (suture)
IO catheterization
- access to capillaries in bone marrow
- useful in neonates, or vasc collapse
- Can cause discomfort
Mean IO flow rates crystalloid solns delivered under pressure (300 mmHg) limited to approx ?????? in puppies?
29 mL/min
IO contraindications
- Don’t do in recently fractured bones
- Don’t do in pneumatic bones of birds
- will drown them
- Inc risk extravasation if in same bone as failed earlier attempt where cortex has been penetrated
IO cath placement
Methods
Sites
- Manually place hypdermic needles or bone marrow needles
- automatic delivery systems exist
- Sites
- flat medial surface of proximal tibia
- tibial tuberosity
- trochanteric fossa of femur
- alternative sites
- wing of ileum, ischium, greater tubercle of humerus
IO complications
- Fat embolism
- Infection
- extravasation fluids
- compartment syndrome
- inc pressure and necrosis if admin at high rates
- bone fractures
Cath care
- change bandage daily or if soiled
- clean site povidone iodine/chlorhex soln
- cath should be flushed Q 4-6hours
- prevents thrombosis w/in cath
- Peripheral caths should be removed after 72 hours OR if signs of
- infection
- phlebitis
- thrombosis
Advantages of nasoesophageal/gastric tubes
- Placement only requires local anesthetic or minimal sedation
- does not require special equipment
- excellent for short term feeding (1-2 weeks)
- NG tube allows for gasric decompression
Disadvantages of nasoexophageal/gastric tubes
- Limited to liquid diets
- may be poorly tolerated
- patient may vomit or sneeze out tube
- NG tube may create incompetance of lower esophageal sphincter
NG/Gastric tubes
TQ
- Limit number of people working with the pet
- label everything
- label food as not for IV use
- Stress to staff that they need to verify food is correctly attached to feeding tube
- not IV cath
- always confirm placement with radiographs or endoscopy
Advantages of Esophageal tubes
- Allows long-term feeding of canned gruel diets
- Relatively easy to place
- Does not require special equiptment
- Can be removed at any time with ease
Disadvantages of esophageal tubes
- Requires general anesthesia
- Patient may vomit tube
- Risk of infection
- Esophageal irritation or reflux
- must wrap neck
When placing esophageal tubes ALWAYS
intubate a patient