anesthesia- endotracheal intubation

benefits of endotracheal intubation

• establish patient airway

• prevent aspiration of vomit or secretions

• intermitent pos pressure vent

• decrease gas exposure to personel

types of et tubes

• murphy tubes (murphy- eye tubes)

• cole tubes

cole tubes

• small animals and exotics

• skinny end inserted into trachea

• tie behind ears

• are easily dislodged

murphy tube

• beveled end

  • easier to insert

• cuff

• pilot line with pilot ballon

• radiopaque strip

pilot line and pilot balloon

• used to inflate/deflate cuff

• pilot balloon has self sealing

• must twist syringe on and off

• always check cuff for leak prior to use

check cuff on et tube for leak

• prior to use

• inflate cuff and let tube sit for a few minutes

benefits of cuffed et tube

• prevents aspiration

• prevents leakage of gas to the room

• prevents animal from breathing room air

cuffed et tube does not

• does not hold tube in place

et tube sizes

• charts based on weight

  • brachycephalics have smaller tracheal diameter

choosing et tube size

• opening of tube fits between the nares

• always choose largest size that will pass easily

length of tube is also important

length should be from tip of nose to thoracic inlet/manubrium

tubes that are too long

• endobronchial intubation

• increased resistance to respiration/ increased dead space

intubation is done at what stage

• anesthesia stage 3

  • plane 1

restraint for intubation

• sternal recumbency

  • can do lateral

• restrainer holds top jaw- not teeth!

• extend neck and raise head

steps for intubation

1. lubricate tube with water,sterile lube, or lidocaine jelly

2. hold tube like pencil with curve down

3. visualize epiglottis

4. visualize vocal folds

5. tube should pass between vocal folds and cuff should just disappear into trachea

best way to confirm tube is in trachea

• visualize tube in the trachea

other methods to confirm tube is in trachea

• feel air with exhalation/tube clouds

• res bag moves with respiration

• palpate for one tube

if tube is in esophagus

• animal won’t stay anesthetized

• animal can vocalize

• animal may become hypoxic

2 ways to know how much air to inflate cuff with

• back pressure in syringe

• use pressure manometer while ventilating

using pressure manometer to inflate cuff

• slight leak at 20 cmH20

• no leak at 15 cmH20

problems with over inflation of the cuff

• compression of the lumen of the tube by over inflation of the cuff

• pressure necrosis or tracheal rupture by over inflation of the cuff

cats are more difficult to intubate why?

• small tracheal diameter

• larynx sits deeper in the neck

• vocal folds cover more of the glottis

• laryngospasms

tracheal tears more common in cats from

• dental procedures/ repositioning

• over inflation of cuff

• injury from stylet

• failure to deflate cuff before extubation

signs of a tracheal tear

• subcutaneous emphysema in 100% of cases

• coughing, upper airway noise, dyspnea, gagging, cyanosis

tx of mild tears w/ mild/mod. dyspnea

• cage rest

• supplemental O2

• sedatives to help prevent vocalization

tx of severe respiratory compromise (severe dyspnea w/ open mouth breathing)

• tracheoscopy to locate tear

• surgical intervention

intubating cats- stylet

• makes small floppy tubes more rigid

• should not extend past the end of et tube

• remove immediately

intubating cats- lidocaine

• to decrease laryngospasms

• draw up 0.1ml, remove needle

• place one drop on each vocal fold

intubating cats- succinylcholine

• neuromuscular blocker (paralytic)

  • relax jaw tone, prevent laryngospasms

• given IV last about 5-10 min

• manual ventilation or ventilator must be performed

  • animal cannot breathe on their own

mouth speculum

• not in cats

• can cause temporary or permanent blindness

  • compresses the maxillary artery which supplies blood to the retina

laryngoscope

• blade to depress base of tongue and light source

problems associated with endotracheal intubation

• pressure necrosis/ tracheal tear

• plugged tube

• kinked tube

• stimulation of vagus nerve

• trauma to larynx, pharynx, vocal folds

• recovering pt could chew tube

extubation

• leave cuff inflated until animal shows signs of recovery

• deflate cuff when showing signs of recovery

• extubate after 2 good successive swallows

et tubes used for airway or oral surgery

• laser resistant tube

• reinforced (armored) et tube

• wrap exposed portion of tube w/ aluminum wire

cleaning et tubes

• w/ dilute antiseptic like chlorhex or dawn dish soap

• ok to submerge under water

• inflate cuff while you wash to get all mucus

• use brush/pipe cleaner to clean inside tube

• rinse well w/ water and hang to air dry

SAD

• supraglottic airway device

• sits in the pharynx and creates a seal around the larynx

advantages of v-gel/ SAD

• decreased risk of laryngeal and tracheal trauma

• decreased chances of post op coughing

• decreased resistance to respiration

• safer smoother recoveries

to insure proper placement can use

• capnograph

• respiratory monitor

• PPV

• esophageal steothoscope