Small Ani. Sx- Larynx, Palate, Nose

drraythe's version from 2016-04-29 14:18

laryngeal paralysis

Question Answer
Definition of laryngeal paralysisFailure of laryngeal cartilages to ABduct on inspiration as a result of degeneration of recurrent laryngeal nerve and paralysis of cricoarytenoideus dorsalis mm (often associated with age)
which breed is esp predisposed to laryngeal paralysis?retrievers
etiology of laryngeal paralysis?UNKNOWN cause of wallerian degeneration of recurrent laryngeal
who is most likely to get laryngeal paralysis?most often in med to large breed dogs, occasionally in cats
what condition might be associated with laryngeal paralysis in dogs?hypothyroidism
laryngeal paralysis is AKA?aka GOLPP- geriatric onset laryngeal paralysis polyneuropathy
most geriatric dogs dx with laryngeal paralysis are in fact presenting with..chronic, progressive polyneuropathy
how does larynx appear when pt inspiring vs resting? (pic)
history that pt with laryngeal paralysis will present with?inspiratory dyspnea, stridor, change in voice, cyanosis
what kinda weather can make laryngeal paralysis worse?hot weather
how will pt appear when they have laryngeal paralysis?neck extended out, commissure of lips super far back, front legs abducted
best way to dx? why this way?you want to have the pt on the verge of anesthesia but not anesthatized- use some propofol and titrate slowely. Don't want totally anesthatized bc then cartilages don't move. Can use laryngoscope to then inspect movement of cartilages. You will want to pull tongue forward firmly and that will help get the epiglottis out of the way too. Then push down root of tongue. This is the best way to get a look inside the larynx.
what are three possible sx treatments for laryngeal paralysis?(1) partial arytenoidectomy (ventriculocordectomy) (2) arytenoid cartilage lateralization ("Tie back" or arytenopexy) (3) laryngoplasty (castellated laryngofissue)
tell owners not to do what if their dog is suffering from LP?NO COLLAR AROUND NECK
what are you doing with a partial arytenoidectomy (ventriculocordectomy)?per os approach use an instrument like a mare endometrial biopsy tool, or scissors and like with a rongeur, you eat up the parts of the arytenoid cartilages to make it wider and allow air to pass better.
what do you have to be careful not to do in the partial arytenoidectomy (ventriculocordectomy)?dont go too far ventrally, bc there is a wound on either end, and the carts arent moving apart, so over time, the two sides might get in contact and cause "Webbing" where they will heal and prevent cart from separating more and build a little dam to not allow passage of air.
how can you prevent webbing in a partial arytenoidectomy (ventriculocordectomy)?you can have ventral approach in this case (usually want to avoid this) but its because you split thyroid cart in half, open larynx, and then remove the vocal folds and the saccules-- this prevents webbing/scar tissue between arytenoids
what is going on with a laryngoplasty (castellated laryngofissue)?ventral midline approach, take thyroid cartilage and cut it like in pic (might be difficult if mineralized, be careful) then move part of thyroid cart in an oral (orad) direction, and because of the shape you cut it in, the sticky outy part will push it apart and it will widen the larynx--> better respiration
what approach do you use for the tie-back procedure?right lateral recumbency
(pic) anatomy/muscles to know for a tie back (arytenoid cartilage laeralization)
how to perform arytenoid cartilage laeralization (tie back)?R lateral approach, place stay suture in thyroid cart for better exposure- need to reach free edge of thyroid cart. Do blunt dissection between fibers of thyropharyngeous muscle (most books say transverse but this has probs assocaited with it- see other card). Then separate joint between the thyroid cart (cart on sides) and the cricoid cart. At this point you can place your stay suture he mentioned before which allows you to pull cart outward. Then free up joint between arytenoid (dorsal cart) and cricoid (ring shaped most caudal). You will place suture around cricoid cart and through arytnoid-- this will tie them back (why it is called tie-back) bc pulling arytenoid in a ca(aborad) direction and a bit to t he side too (some ppl add another suture from arytnoid to thyroid for more support)
how should you NOT get to edge of thyroid cart- and why?if you cut transversly along edge of thyroid cartilage-- but then you cut the mm on the side, and then have to suture it back, the mm loses its contractibility and synergism with all the other pharyngeal mm which might cause delay in the swallowing --> possible aspiration pneumonia
is a tie back done uni or bilateral?UNILATERAL!! bc bilateral the opening would be too big and then there is a higher chance of aspiration pneumonia (pic is normal, with paralysis, and a completed tie back)
how do you know if you are tieing the tie back enough or not?after preplace sutures, and ready to tie sutures, somebody from the team that isnt scrubbed will open mouth, pull out ET tube, and see how much you're pulling. So then they can tell you if you have tied enough to have a decent opening for pt to breathe, but not too much or too little. Then reintubate the pt. *important to do this
complications of arytnoid cart lateralization?(1) aspiration penumonia (help avoid this by performing procedure on one side only) (2) failure to correct conditon- could be inadequate lateralization, failure to correct associated hypothyroidism, or a misdiagnosis of the cause of dyspnea

Brachycephalic airway syndrome/ BOAS

Question Answer
brachycephalic airway syndrome is aka BOAS, which means...brachycephalic obstructive airway syndrome
BOAS is charaterized by what primary upper airway charateristics? (3) secondary? (2)PRIMARY: stenotic nares, elongated soft palate, hypoplastic trachea. SECONDARY: everted laryngeal saccules, laryngeal collapse. With all of this combined you will see signs of upper airway obstruction
wuts dis? everted laryngeal saccules
what are some ways to try to medically manage BOAS?strict weight loss program, reduced exercise, harness (not collar), steroids for short term, sedatives, avoid hot environment
what are the two procedures you can perform on the nose for BOAS?alaplasty, alapexy
what do you do in an alapexy?make incision on the lateral aspect of the nares, and then the nearby skin, and then suture back wall then front wall. This pulls the cartilage outward, enlarging entrance.
what do you do in an alaplasty?you are basically removing the colored portion (see pic) so removing that pyramidal piece of flesh. Or in an alternative method, you can take a wedge from the most caudal aspect of the nares at the junction of the skin (pulls outward to open nares)
what else in the nose can be a problem aside from the stenotic nares?malformation of turbinates
how do you sx tx the elongated soft palate?pt placed in sternal recumbency, and then have it so mouth is maintained open as wide as possible. (elevate maxilla, and then mandible is tied down to table). make sure anesthesia has an elbowed breathing system so it isnt in your way. Then few diff methods: (1) with stay sutures, pull soft palate out to be as exposed as possible. then mark with marker or stitch where you will be cutting. Need to be precise and careful with cut bc buccal and pharyngeal side need to be equal. Might make too short- problem. err on the long side. Then begin cutting with scissors (pack pharynx with lap sponge bc there is gonna be blood and dont want it in larynx). so cut half, then suture edges together (simple cont or simple interrupted). Then do other half. Then remove stay sutures.
what problem arises if you cut the soft palate too short?when they drink water can backwash into nose--> rhinitis
aside from with scissors or traditional instruments, what other tools can you use to remove soft palate? (2)(1) CO2 laser- dont need to suture. *careful bc can cause lots of inflammation (2) ligasure- cauterizes while it cuts.
when pt recovering from soft palate removal, when remove ET tube?dont remove until theyre already chewing it- make sure they can breathe! monitor recovery closely
what is going on in a folded flap palatoplasty?sometimes not sure how much length of soft palate to remove. with this procedure, took thickened soft palate and remove piece of thickeness from buccal side. Then soft palate is thinner. Then fold pharyngeal mucosa the length you consider appropriate (can calc length perfectly). Then sew flap together. stitches are on soft-hard palate side and not on edge (which can irritate surrounding tissues).
what is normal length of soft palate?tip of soft palate should touch tip of epiglottis

laryngeal collapse/ rhinoscopy/ exploratory rhinotomy

Question Answer
what is the procedure of choice for a laryngeal collapse? why?permanent tracheostomy bc complications are minimal and prog is generally good. (technique discussed in other section- remember pt can no longer swim!)
what are some things you can do to make your permanent tracheostomy for laryngeal collapse more effective, and what things should you warn owners about?if pt is a wrinkly saggy baggy skin type, the skin folds might intermittently obstruct stoma- be careful, try to prevent this problem. also vocalization is diminished or absent. also no swimming! also need to keep area clean (get rid of mucus) and clip long hair short.
what is rhinoscopy used for?visualization and bx of rostral 1/3 of nasal cavity (look for FB, mites, neoplasia whatever)
where do neoplasia of nose tend to be? (kinds?)inside nose at level of medial canthus of eye (Adenocarcinomas or carcinomas) locally aggressive (can eat away at bone and hard palate) but slow growing with slow metastasis
how can you visualize the back of the nose?flexible endoscope
how to perform core biopsy of nasal passages?perform under anesthesia. measure cannula against pts muzzle before inserting. Need a 12cc syringe and a 3-5mm plastic cannula.
what are the 2 sx approaches to the exploratory rhinotomy? (what can you get at with these appraoches?)(1) dorsal- to rostral nasal cavity and to sinunses (more limited) (2) ventral- entire nasal passage, including area caudal to ethmoid turbinates
3 types of reasons you might wanna do a exploratory rhinotomy?(1) establish drainage, remove FB (2) dx procedure for obtaining bx and culture specimens (3) indicated for tx of nasal adenocarcinoma, but must be accompanied by other tx modalities (radiation therapy)
imaging signs which strongly point to nasal adenocarcinoma?vomer bone is eaten away, if goes into the orbit, get eye prolapse/ buphthalmia, bleeding when sneeze
how to do exploratory rhinotomy procedure?towel clamps grabbing apart from eyes, dont grab upper eyelid (and leave nose exposed). make incision from about medial aspect of eyelids up to close to the nares. If there is bone, peel off periosteum, then with chisel/hammer/saw open up and take piece of bone off. once in there, work very fast and curette out content of nasal cavity. need to remove all mucosa of nasal cavity plus the tumor. careful not to go beyond medial canthus of eyes, bc that's where the ethmoid bone is, with the cibiform just behind that (and then brain so yikes). Flush continuously. can have saline in freezer so it's like icy slush to shrink capillaries. With sponge go back and forth through nares trying to remove as much as you can. need to be super aggressive and scrape a lot. Then place drain, exit drain thorugh hole at level of frontal sinus and bring in gauze, apply packing very tightly. packing prevents 2* bleeders and allows for good coag. 3-5 days later remove drain. Once gauze packed, replace bone piece, sew periosteum over that, then SQ and skin
possible complication of exploratory rhinotomy if you don't let there be a draining hole?SQ emphysema (balloon head)