Low Respiratory Surgery Flashcards
The dorsal tracheal membrane is made of these three things:
- Mucosa
- Connective tissue
- Trachealis muscle
The vascular supply of the trachea and bronchi is ______, from cranial and caudaul _____ and _____ arteries.
Segmental; thyroid, bronchial
The recurrent laryngeal nerve lies at the ______ edges of the trachea ____ to the heart.
dorsolateral; cranial
Two muscles to cut through to get to the ventral aspect of the cervical trachea:
- Subcutaneous trunci m.
- Sternohyoideus m.
The surgical approach to the thoracic trachea is from the ____ side, at the ___rd ICS.
Right (esophagus is on the left), 3rd ICS
Poster child for tracheal colapse
Yorkie (mini and toy breeds)
Clinical signs of tracheal collapse
- Coughing
- Dyspnea
- On inhalation: cervical trachea collapsed
- On exhalation: thoracic trachea collapsed
Tracheal collapse pathophysiology
- Congenitally hypoplastic or fibrodystrophic cartilaginous rings
- Redundant or weak dorsal tracheal membrane
- May involve both cervical and thoracic trachea
- May extend to mainstem bronchi (and lower)
Four grades of tracheal collpase are based on _____ .
% of lumen reduction
Grade I - 4 Tracheal Collapse
- Grade I - 25% lumen reduction
- Grade II - 50% lumen reduction
- Grade III - 75% lumen reduction
- Grade IV - almost no lumen
Medical treatment is typically preferred (vs surgery), especially in grades I and II tracheal collapse. True or False.
True
Medical treatment of tracheal collapse
- Cough suppressants
- Bronchodilators
- Antibiotics (if complicated by bacterial infection)
- Control complicating factors - obesity, heat stress, leash irritation (harnes vs collar)
Surgical treatment of tracheal collapse
- When medical treatment cannot control clinical signs
- Limited ability to alleviate bronchial collapse
- Intraluminal stents or extraluminal rings/prostheses
Dorsal tracheal membrane prication is not typically performed becuase it requires relatively normal tracheal cartilages. True or False.
True
Extraluminal prosthesis are made from _______ syringe, or syringe cases.
Polypropylene syringe
Which is preferred:
Total ring prostheses or spiral-shaped prosthesis?
Total ring prostheses are preferred. Spiral shaped ones restrict blood supply.
How do you treat tracheal hypoplasia?
No surgical care or treatment, simply use smaller endotracheal tube.
Two common causes of internal injury to the trachea or bronchi?
- Intubation can damage trachea
- Foreign bodies
Tracheal stenosis is ____ due to trauma.
Scar tissue
Treatment options for tracaheal stenosis
Most commonly we do a resection/anastomosis. Can also do a bougienage, balloon dilatation, and or stent.
Predominant clinical sign of blunt or penetrating tracheal trauma
Persistent peritracheal, subcutaneous, and/or mediastinal emphysema
Most tracheal tears resolve without surgical intervention. True or False.
True
Temporary tracheostomty are almost always necessary to decrease airway resistance in tracheal lacerations. True or False.
False - rarely necessary!
List the three anastomotic techniques ofr tracheal resection/anastomosis, and which one is preferred.
- Split-cartilage technique - preferred b/c results in less stenosis from healing
- Annular ligament-cartilage technique
- Interannular technique
In a split cartilage technique, two rings of _______ are split, and the sutures are placed on either side of the rings, through the ______ _____.
cartilage; annular ligaments
Make sure to place sutures in the ______ muscle before other sutures when performing a tracheal anastomosis.
trachealis muscle
Tension-relieving sutures are placed around rings _____ to primary repari to minimize stenosis. (distant or close).
Distant
Indications for tube tracheostomy
Life-threatening upper airway obstruction.
Inhalation anesthesia for upper respiratory and intraoral surgery.
Removal of secretions and aspriated material.
When we just want to bipass the main airways, and not ventilate for anesthseia, do we prefer tubes with or without cuffs?
Without cuffs - because cuffs can accumulate secretions
Tube Tracheostomy Preparation:
Preparation of neck for ventral cervical incision from the _______ caudally for a distance equal to __ or ___ tracheal rings.
cricoid cartilage caudally; distance equal to 3-4 tracheal rings
Surgical tehchnique for tube tracheostomy
- Ventral midline incision from cricoid cartilage to about 3-4 cm caudally
- Separate sternohyoideus muscles on midline
- Transverse interannular incision between trachea rings 2 and 3 (or 3 and 4)
- Knotted stay sutrues around rings 2 and 3
- Insert and secure tube with umbilical tapes tied behind the neck.
When performing a tube trahceostomy it is important to outline ____ and _____ cartilages on the skin before incision.
Thyroid and cricoid
The ideal skin incision site for tube tracheostomy is more ____. (caudal or cranial).
Cranial
Tracheal rings are exposed with help of _____ retractors separating the sternohyoideus muscles.
Gelpi
For tube tracheostomy, when making the incision, the endotracheal tube should or should not be visible int he tracheal lumen at this point?
Should be visible
It is important to remove the endotracheal tube immediately right before placing the tracheostomy tube. It is also imporant to knot and retain stay sutures. Why?
These stay sutures are there to make it easier if the tracheostomy tube needs to be replaced. When the tube is taken out - the trachea and muscles quickly cose shut - and wil be difficult to open up quickly. With the stay sutures - can easily pull the sutures, to pull the incision apart and expose the tracheal lumen.
After introducing the tracheostomy tube with the aid of stay sutures, the next step is to…
secure the wings of the tube with umbilical tapes tied behind the neck
Treacheostomy tube removal is allowed when effecting breathing occurs _____ the tube.
The wound heals by ____ intention.
around tube; second intention
Permanent tracheostomy indications
- Salvage procedure!
- Untreatable upper airway obstruction (palliation for nonresectable laryngeal neoplasia)
- Upper airway treatment failure (failed treatment of laryngeal paralysis)
Permanent Tracheostomy - Surgical Technique via Ventral Midline Approach
- Secure sternohyoideus muscles together dorsally to the trache (matress sutures)
- Rectangular section of ventral trachea at rings 2, 3, and 4
- COrresponding rectangular section of skin
- Suture skin edges to tracheal mucosa - suture skin to trachea to obliterate dead space and control obstructive skin folds
How to reverse permanent tracheostomy:
incise skin-mucosa junction and suture skin edges
List surgical conditions of the lungs:
- Pulmonary cysts, bullae, or blebs
- Pulmonary abscess
- Restrictive pleuritis
- Bronchiectasis
- Bronchial forign bodies
- Lung laceration
- Lung lobe torsion
- Pulmonary neoplasia
What makes cysts different from bullae and blebs?
Cysts are lined with epithelium; bullae and blebs are not.
Almost exclusively ___ and ____ may cause spontaneous (idiopathic) pneumothorax.
bullae and blebs
Air filled cyst is called a:
Pneumatocele or Pneumatocyst
Pulmonary bullae vs. blebs
- Bula is deep in the lung, sometimes requiring attentive palpation to locate
- Bleb is located peripherally in the lung and is easily seen.
Treatment of pulmonary abscess
Medical - antibiotic therapy, pleural drainage if pyothorax
Surgical resection - partial lung lobectomy
Restrictive Pleuritis - occurs when heavy ___ deposites after truama or inflammation of the ____.
Fibrin; pleura
Sequela to chylothorax
restrictive pleuritis
surgical treatment of restrictive pleuritis
Lung decortication - very poor results
Bronchiectasis is congenital or acquired _____ of bronchi and bronchioles. It contributes to recurrent _______ ____.
dilation; respriatory infections
Surical treatment of bronchiectasis
Lobectomy of affeted lung lobes if only one or two lobes are involved.
Do bronchial foreign bodies require lung lobectomies?
May require a lung lobectomy if the foreign body cannot be removed endoscopically.
Lung lacerations are usually small and resolve _____ with aid of ______ drainage.
spontaneously; thoracic drainage
MC lung laceration -
Iatrogenic during thoracotomy
Indications and techniques of surgical tx for lung laceration
- Indications
- Uncontrollable or unresolving pneumothorax
- Ongoing intrathoracic hemorrhage > 2ml/kg/hr
- Techniques
- Continuous inverting suture pattern (example: lembert)
- Deep hemostatic mattress suture with simple continuous closure of laceration
- Partial or complete lobectomy
Which lung lobe is the most common in lung lobe torsions? Followed by?
Right middle lung lobe, followed by right cranial and left cranial
Signalment for lung lobe torsion
Deep, narrow-chested dogs
Treatment of lung lobe torsion
Lobectomy - do NOT untwist!
Pulmonary neoplasia - which is more common, metastatic or primary?
Metastatic
What is the most common primary pulmonary neoplasia?
Pulmonary adenocarcinoma
Techniques of partial lung lobectomy with sutures:
- Clamps are ____ to the lesion
- Continuous ______ ____ pattern proximal to clamps
- Incsision made between ____ and _____, or between ____ and ___.
- ____ ____ oversew of incised edge.
- Clamps proximal to lesion
- Continuous horizontal mattress pattern proximal to clamps
- Incision between clamps and horizontal mattress, or between clamps and lesion.
- Simple continuous oversew of incised edge.
Complete pulmonary lobectomy
- dissect hilus to identify pulmonary artery, bronchus, and pulmonary vein
- Ligate/divide artery, then vein, then bronchus
Artery, bronchus, and vein can be closed simultaneously during pulmonary lobectomy with a ______
thoracoabdominal stapler
Pneumonectomy is excision of entire lung on one side of the thorax - can only remove entire left side, but not the right, why?
The right lung is larger, and covers more than 50% of total lung mass. You can only remove 50% of lung acutely, and therefore cannot remove te whole right lung.
You can only remove ___% of lung acutely, and probably more if non-diseased lung already compensating.
50%
Indicationsof thoracostomy tube
- Post-op thoracotomy - to manae residual air and fluid
- Mangement of pneumothorax
- Management of pleural effusions (hydrothorax, hemothorax, pyothorax, chylothorax)
With thoracostomy tube placement - closed thorax - a special tube with a ____ stylet is used. An alternative would be using tube tip in tips of ____ forceps.
Trochar; carmalt
With a thoracostomy tube placement - closed thorax - make your stab incision as small as possible, in the dorsal ____ of the lateral thorax near ___ to ___ ICS.
1/3; 10th to 12th
When performing a thoracostomy tube placement - close thorax - place the sub-latissimal tunnel carnioventrally to __ or ___ ICS at the mid-____.
7th or 8th; mid-thorax
Three basic steps of closed thorax thoracostomy tube placement:
- Stab skin incision (as small as possible) - dorsal 1/3rd of lateral thorax 10th to 12th ICS
- Sub-latissimal tunnel - cranioventrally to 7th or 8th ICS at mid-thorax
- Controlled “thrust” into thorax (or puncture ICS with carmalts before ontroducing tube)
In an open thorax thoracostomy tube placement, is a trochar-type tube necessary?
No
Thoracostomy tube - securing the tube how?
Chinese finger trap
When securing a thoracostomy tube, friction sutures must engage underlying ____ or _____ of the closest rib.
fascia or periosteum
Most common surgical approach to the pleural space:
Intercostal thoracotomy
In the left 4th ICS Thoracotomy, which muscle is retracted?
Latissimus dorsi muscle
Transternal thoracotomy requires _____ recumbence, and has no advantage over ____ sternotomy.
Dorsal; median
Median Sternotomy
- Performed when a large opening or access to the entire thoracic cavity is necessary
- Permits complete thoracic cavity exploration
- Seems to cause no more postoperative pain and morbidiy than other thoracic approaches
Suture material and pattern for median sternotomy closure
Heavy polydioxanone or polypropylene pre-placed figure-of-eight sutures
Paramedian sternotomy has the same advantages and usefulness as median sternotomy, but does not require _____ of sternebrae.
Osteotomy
Transdiaphragmatic approach to the thoracic cavity has been used for:
- thoracic duct ligation in cats
- Epicardial pacemaker lead placement
- Open-chest cardiopulmonary-cerebral resuscitation during abdominal surgery
Pectus Excavatum vs Flail Chest
- Pectus excavatum - congenital, inward concavity of the sternum, fixed with external splint with sutures that encircle the sternum and pull the sternum towards the splint
- Flail chest - traumatic injury where two or more ribs are fractured dorsally and ventrally leading to paradoxical chest motion (segment moves inward during inhalation and outward during exhalation), if surgery indicated can use splint, but most of the time treat medically, NOT surgically
