Respiratory and Thoracic Surgery Flashcards
When would you use a Nasal Planum Resection?
Unilateral Neoplasia
What will happen to dogs if you allow the Nasal Planum Resection to heal by second intention?
Nasal Stenosis
What are the complications of Nasal Planum Resection?
Dehiscence
Stenosis
When would you perform a Nasal Planectomy and Maxillectomy?
Oral Fibrosarcoma
What must you do to decrease the likely hood of nasal stenosis?
Fold the skin to appose skin and nasal mucosa
What do you gain access to with a Dorsal Rhinotomy?
Nasal cavity and sinuses
What do you gain access to with a Ventral Rhinotomy?
Access to ventral nasal cavity and choanae
What are the risks and complications of Nasal Surgery?
Hemorrhage Flap necrosis Oronasal fistula Dehiscence Stenosis of airways Incomplete resection/local recurrence
What are the Primary Components of Brachycephalic Airway Syndrome?
Elongated Soft Palate
Stenotic Nares
Shortened flattened nasal cavity
Hypoplastic trachea
What are the secondary/acquired components of Brachycephalic Airway Syndrome?
Everted laryngeal saccules/Stage I laryngeal collapse Pharyngeal/ laryngeal mucosal edema Tonsillar eversion Macroglossia Stage II/ III Laryngeal collapse Tracheal collapse
What is the clinical sign of Elongated Soft palate?
Inspiratory dyspnea: Stertor
What does an Elongated Soft Palate cause?
Extension into Rima Glottidis: Severe obstruction or Loss of Protective Laryngeal function
What is the most common component of Brachycephalic Airway Syndrome?
Elongated Soft Palate
Stenotic Nares
Abnormal anatomy causes external and internal resistance - The inability to dilate nostrils
What are the 3 stages of Laryngeal collapse?
Stage 1: Everted Laryngeal saccules
Stage 2: Collapse of cuneiform cartilage
Stage 3: Collapse of corniculate cartilage
Chondromalacia
loss of cartilage rigidity
What are the characteristics of Hypoplastic trachea in English Bulldogs?
Irregular, thick/firm cartilage rings
Overlap of rings
Increased airflow resistance
What are the cardiovascular changes that lead to right heart failure in dogs with Brachycephalic Airway Syndrome?
Chronic decreased PO2 secondary to airway obstruction
Pulmonary vasconstriction
V/Q Mismatch
Subsequent vasoconstriction/hypertension
What are the clinical signs of Mild/Moderate Brachycephalic Airway Syndrome?
Exercise Intolerance
Increased noise: Snoring, Snuffing, reverse sneezing
+/- gastrointestinal signs
What are the clinical signs of Severe Brachycephalic Airway Syndrome?
Acute respiratory distress Upper airway swelling, hyperthermia, cyanosis Heat stroke Gatrointestinal signs Lower airway disease Non-cardiogenic pulmonary edema Aspiration pneumonia
What drugs should you avoid in your Upper Airway Exam for Brachycephalic airway Syndrome?
Ketamine
Diazepam
pure mu agonists
What should you assess Thoracic Radiographs for with Brachycephalic syndrome?
Right heart enlargement Hypoplastic trachea Non-cardiogenic pulmonary edema Aspiration Pneumonia Hiatal hernia Megaesophagus
When is surgery necessary for Brachycephalic Airway Syndrome?
Presence of any component of BAS
How do you correct Stage 1 laryngeal collapse of Brachycephalic airway syndrome?
Excision of everted laryngeal saccules
How do you correct Stage 2 laryngeal collapse of Brachycephalic airway syndrome?
Above + vocal fold excision, partial arytenoidectomy
How do you correct Stage 3 laryngeal collapse of Brachycephalic airway syndrome?
Permanent tracheotomy
How do you correct Soft Palate resection of Brachycephalic airway syndrome?
Palatectomy/Palatoplasty
What are some Preoperative Therapy Considerations for surgery for corrections of Brachycephalic airway syndrome?
GI Protectants Promotility agents Anti-inflammatories Anti-emetics Pre-oxygenation
How should you position the patient for surgery for Brachycephalic airway syndrome?
Maxilla hanging from IV poles
+/- mouth gag
Endotracheal intubation - Ensure cuff is inflated
Gauze packing of larynx
What are the different tools for Palatoplasty-Paletectomy?
Sharp dissection
CO2 laser excision
Bipolar sealing device excision
What is the most traumatic technique for a Palatoplasty-Paletectomy?
Clamp (Crush) Technique
Describe the Freehand Technique for Palatoplasty-Paletectomy
Amputate soft palate to midline with scissors on one side then suture to midline
Amputate remaining palate and suture
What are the advantages to the Laser Freehand technique?
Rapid Virtually no blood loss excellent visualization Minimal post-operative inflammation Reduced post-operative discomfort
What are the Acute complications of Palatectomy?
Hemorrhage
Inflammation
What are the Chronic complications of Palatectomy?
Undershortening
Overshortening: Nasal Reflux or Aspiration
What are the complications with arytenoidectomy and ventriculochordectomy?
“webbing” or stricture
What are the different techniques for Stenotic Nares?
Wedge Resection: Horizontal, Vertical, or Dorsolateral
Amputation of the Alar wing +/- alar fold
Alaplexy
When would you perform a Unilateral Arytenoid lateralization?
Only in causes of laryngeal paralysis and if adequate cartilage rigidity is present
What analgesia do you use with post-operative care of Brachycephalic airway syndrome surgery?
Buprenorphine
What Medical Treatment is important for Brachycephalic airway syndrome surgery Post- operative care?
Weight Loss
Harness
Treat underlying GI disease
What are some major Post-operative complications of Brachycephalic airway syndrome surgery?
Pharyngeal swelling: Acute distress
Vomiting
Regurgitation
Aspiration Pneumonia
What are some minor post-operative complications of Brachycephalic airway syndrome surgery?
Dehiscence of nares: recurrence of stenosis Bleeding Persistent stertor/stridor Rhinitis/Sinusitis Voice change
What is the surgical treatment for Epiglottic Retroversion?
Surgical plexy of the ventral aspect of the epiglottis and the dorsal base of the tongue
What is the cause of Epiglottic Retroversion?
Laxity of hyoepiglotticus m. in face of extreme inspiratory effort
What are the clinical signs of Laryngeal Disease?
Respiratory Stridor Exercise Intolerance Gagging/Dysphagia Dysphonia Coughing Dyspnea that does not improve with open mouth breathing
What muscles are responsible for laryngeal abduction?
crycoarytenoideus dorsalis
What nerves innervate the crycoarytenoideus dorsalis muscle?
Cranial and caudal laryngeal nerves
What nerve is the origin of the cranial laryngeal nerve?
vagus nerve
What nerve is the origin of the caudal laryngeal nerve?
vagus nerve through the recurrent laryngeal nerve
What are the 3 functions of the Larynx?
Swallowing
Abduction
Voice Production
In what breeds does Congenital Laryngeal Paralysis occur?
Bouvier de Flandres Huskies Bull Terriers Dalmations Rottweilers
What are the characteristics of Congenital Laryngeal Paralysis in Bouvier de Flandres, Huskies, Bull Terriers, and Dalmations?
Progressive degeneration of neurons with onset before 1 year
May have cranial tibial muscle paralysis
What are the characteristics of Congenital Laryngeal Paralysis in Rottweilers?
Progressive generalized degenerative disease
Onset of signs between 11 and 13 weeks
Ataxia, paresis, head tremors, and neurogenic muscle atrophy
What is the most common cause of Acquired Laryngeal Paralysis?
Idiopathic
What do you see on radiographs for Laryngeal Paralysis?
Aspiration pneumonia
Megaesophagus
Cranial mediastinal masses: Thymoma
Non-cardiogenic pulmonary edema
What is the surgical treatment of Laryngeal Paralysis?
Unilateral arytenoid lateralization
Describe the Unilateral Arytenoid Lateralization technique?
Secure the muscular process of the crycoid to the arytenoid
Poiseuille’s Law
In laminar flow resistance to flow is inversely proportional to the radius to the fourth power
What does Excessive torsion increase the risk of?
aspiration pneumonia due to poor epiglottic coverage of rima glottidis
What should you avoid with Post-op care after Unilateral Arytenoid Lateralization?
heavy sedation or medications that may incite nausea/vomiting
What are the complications of Unilateral Arytenoid Lateralization?
Aspiration Pneumonia Seroma Intramural hematoma coughing gagging dysphagia
What structures would you be approaching with a Cervical Ventral Midline Approach?
Sternohyoideus and sternothyroideus mm. Recurrent Laryngeal n. Vagosympathetic trunks R and L common carotid arteries Thyroid glands Esophagus
What structures would you be approaching with a Median Sternotomy?
Caudal and cervical thoracic trachea
What structures would you be approaching with a Right 3rd Intercostal Space Thoracotomy?
Cranial Thoracic trachea
What structures would you be approaching with a Right 4th Intercostal Space Thoracotomy?
Tracheal Bifurcation
What is the Pathophysiology of Tracheal Collapse?
Progressive irreversible degeneration of lower airway
Laxity of trachealis muscle
Hypocellular Tracheal cartilage
Increased weakness/pliability
Decreased water retention secondary to loss of glycoprotein and GAG
Progressive cough
What are the secondary factors leading to Tracheal Collapse?
Obesity
Environmental allergens
Respiratory Irritants
Kennel Cough
What is the signalment for Tracheal Collapse?
Small and toy breed dogs
Middle aged dogs
Clinical signs of Tracheal Collapse
"Goose Honk" Progressive Cough Waxing and waning dyspnea Exercise intolerance Cyanosis Syncope
Where does the collapse in the trachea occur during inhalation?
cervical
Where does the collapse in the trachea occur during exhalation?
Thoracic
What should you perform to diagnose Tracheal Collapse?
Fluoroscopy
Tracheoscopy
What is the gold standard for diagnosis of Tracheal Collapse?
Tracheoscopy
Grade 1 Tracheal Collapse
25% lumen reduction
Grade 2 Tracheal Collapse
50% lumen reduction
Grade 3 Tracheal Collapse
75% lumen reduction
Grade 4 Tracheal Collapse
Almost no lumen
When do you consider surgical treatment for tracheal collapse?
When Medical Management fails
How do you treat cervical tracheal collapse?
External Prosthetic Tracheal Rings
What are the complications associated with External Prosthetic Tracheal Rings?
Laryngeal Paralysis
Tracheal necrosis
Pneumothorax
What are the surgical options for treating Tracheal Collapse?
External Prothetic Tracheal Rings
Intraluminal Stent
Intraluminal Stent
Self-expanding nitinol stent placed fluoroscopically or endoscopically
What are the advantages of the Intraluminal Stent?
Minimally invasive
Shortened anesthesia time
Can be used in the cervical or thoracic trachea
Immediate improvement in clinical signs
What are the disadvantages of the Intraluminal Stent?
Requires fluoroscopy or endoscopy
$$$$$
Shorter life-span than tracheal rings
Moderate to high complication rate
What are the complications of stenting?
Stent fracture Stent migration Tracheitis Collapse beyong stented region Tracheal obstruction secondary to granulation tissue formation Tracheal rupture
What are the clinical signs of Tracheal Trauma?
Subcutaneous emphysema Anorexia Lethargy Stridor coughing Dyspnea Mediastinal emphysema Pneumothorax
When is surgical intervention of Tracheal Trauma indicated?
Dyspnea persists or worsens with medical management
If pneumothorax persists for more than 2-3 days
Severe tracheal damage is visible
What are the options for surgical intervention of Tracheal Trauma?
Primary closure of tear
Tracheal resection and anastomosis
What kind of suture is used in Tracheal Trauma?
Fine absorbable suture
What are the complications of surgical repair of Tracheal Trauma?
SQ emphysemaa
Pneumomediastinum and pneumothorax
Infection
Stricture
When would you perform a Permanent Tracheostomy?
Salvage procedure for treatment of untreatable upper airway obstruction
Permanent Tracheostomy
Creates permanent opening at level of proximal cervical trachea
What are the complications of Permanent Tracheostomy?
Infection Bleeding stenosis foreign bodies increased risk of pneumonia drowning
Why is prognosis for for cats with permanent tracheostomy?
Mucus plugs are very common and lead to acute death
What is the most common surgical approach to the thorax?
Lateral Thoracotomy
Combined Abdominal and Median Sternotomy
Lesions where access to both sides of the diaphragm facilitate surgery
Transdiaphragmatic Surgical Approach
Allows access to thoracic cavity during celiotomy
When would you perform a Transdiaphragmatic Surgical Approach
thoracic duct ligation Portoazygous EHPS ligation epicardial cardiac pacemaker lead implantation surgery of the caudal esophagus intra-operative CPR/cardiac massage
When would you perform a Rib Resection/Pivot lateral Thoracotomy?
remove or pivot rib to increase exposure or remove masses too large to exteriorize through standard level thoractomy
When would you perform a Median Sternotomy?
Bilateral thoracic exploration
Cranial mediastinal masses
Cranial thoracic trachea
What would you close with in a Median Sternotomy?
Polypropylene sutures
Orthopedic wire
What are the special considerations for Thoracic surgery?
Positive Pressure Ventilation required
Chest tube commonly required post-operatively
Pneumonectomy
Removal of all lobes of one lung
When is a Pneumonectomy indicated?
where disease is diffuse through multiple lung lobes
What approach do you use for a Pneumonectomy?
lateral intercostal approach
When would you use Guilllotine suture in a partial lobectomy?
biopsies and very small peripheral masses
What is the suture technique for complete lobectomy?
Triple ligation of vessels
Pre-place horizontal mattress sutures and tie prior to transection
Oversew transected end of bronchus
What is the advantage to Stapling technique for a Partial/Complete Lobectomy?
Decreased anesthesia and surgery time
What is the disadvantage to the Stapling Technique for a Partial/Complete Lobectomy?
Standard devices too large for very small patients
What should you check for with Pulmonary Surgery?
Bleeding/Hemorrhage
Air Leakage
Chest Tube placed via separate intercostal incision
What type of wound is a Lung Biopsy?
Clean-contaminated
Bleb
localized collection of air between internal and external layer of visceral pleura
Bullae
non-epithelized cavities produced by disruption of intraalveolar sepsis
Cysts
Closed sacs lined by epithelium filled with fluid or air
Pleurodesis
Lung is fused to the body wall
What is conservative treatment for Cysts, Bullae, and Blebs?
Thoracostomy tubes for 48-72 hours
What are the possible causes of Lung Lobe Torsion?
Pleural effusion
Partial collapse of lung lobe
What dogs are affected by Lung Lobe Torsion?
Large deep chested dogs and pugs
Which lung lobes are affected by Lung lobe torsion in large dogs?
Right middle or left cranial lung lobe
What lung lobe is affected by Lung Lobe torsion in Pugs?
Left Cranial lung lobe
Clinical signs of Lung lobe Torsion?
Acute onset of Dyspnea Tachycardia Cough Exercise Intolerance Hemoptysis Pyrexia pale MM Decreased lung sounds ventrally
What do you see on Thoracocentesis of Lung Lobe Torsion?
Serosanguinous or chylous effusion
What should you not do with Lung Lobe Torsion?
Do not untorse the lung
Avoid release of cytokines and endotoxins- Reperfusion injury
What are the most common types of Primary Pulmonary Neoplasia?
Bronchiolar or alveolar carcinoma
When would you perform a Lung Lobectomy for Primary Pulmonary Neoplasia?
Peripheral tumors not involving the hilus
Where do you get Squamous cell carcinoma in the lung?
Cranially
Where do you get Adenocarcinoma in the lung?
Caudally
What is important to remember with Penetrating Chest Wounds?
DO NOT REMOVE OBJECTS PENETRATING CHEST WALL
How do you treat penetrating chest wounds?
Debride any severely damage muscle
Repair intercostal lacerations
Place a thoracostomy tube
What causes Flail Chest?
Multiple segmental rib fractures
Flail Chest
Flail segment moves paradoxically with chest wall during respirations due to rib fractures
How would you treat Flail Chest?
Interfragmentary wire
Cross Pinning of the rib fractures
Splint
What is the most common cause of Chylothorax?
Idiopathic
What is the treatment for Idiopathic Chylothorax?
Thoracic duct ligation
Cystena chyli ablation
Subtotal pericardiectomy
What will improve the visualization of mesenteric lymph nodes?
Lymphangiography
Injection of methylene blue into the mesenteric LN
Why would a pericardectomy be performed with chylothorax?
Chylothorax causes fibrosis of the pericardium
What is performed with thoracic duct ligation to maximized success of the surgery?
Subtotal pericardectomy
What are the complications of CIsterna Chyli Ablation?
Persistent chylous or non-chylous effusion
Lung Lobe torsion
Pneumothorax
Diaphragmatic Hernia
Loss of continuity of diaphragm resulting in movement of abdominal organs into thoracic cavity
What is the most common diaphragmatic hernia cause?
Trauma
What is the pathophysiology of Diaphragmatic Hernia?
Rapid deflation of lungs with open glottis produces large pleuroperitoneal pressure gradient
What are the acute clinical signs of Diaphragmatic Hernia?
Respiratory Distress (tachypnea, dyspnea, cyanosis) Shock
What are the chronic clinical signs of Diaphragmatic Hernia?
Respiratory and Gastrointestinal signs Dyspnea Lethargy Exercise intolerance Vomiting Regurgitation inappetance Pleural/peritoneal effusion
What is the first thing you should do for treatment for Diaphragmatic Hernia?
Stabilize the Patient
When is surgery emergent with Diaphragmatic Hernia?
When the stomach is herniated
What is the most commonly herniated organ in Diaphragmatic Hernia?
Liver
What suture is used to repair Diaphragmatic Hernia?
PDS
Prolene
What suture pattern is used for Diaphragmatic Hernia repair?
Simple Continuous pattern
What are the complications associated with repair of Diaphragmatic Hernia?
Re-expansion pulmonary edema Persistent Pneumothorax hemorrhage Failure of repair and re-herniation Loss of domain: contracture of the abdominal muscles
Peritoneopericardial Diaphragmatic Hernia
Congenital communication between pericardium and peritoneal cavity
Pentology of defects associated with Congenital Cranial Abdominal Wall and Diaphragmatic Defects
Cranial Abdominal wall defect Caudal sternal fusion defect Pericardial defect Diaphragmatic defect Intracardiac defects
Radiographic signs of Peritoneopericardial Diaphragmatic Hernia
Enlarged cardiac silhouette
Dorsal elevation of trachea
Overlap of heart and diaphragmatic borders
Gas filled structures in pericardial sac
Sternal defects
Dorsal peritoneopericardial mesothelial remnant
How soon should you perform surgery on Peritoneopericardial Diaphragmatic Hernia?
Between 8-16 weeks
Why would you give antibiotics for Peritoneopericardial Diaphragmatic Hernia?
Hepatic compromise may result in release of toxins
What approach would you use for surgical treatment of Peritoneopericardial Diaphragmatic Hernia?
Ventral Midline Abdominal approach
What suture pattern would you use to repair a Peritoneopericardial Diaphragmatic Hernia?
Simple continuous pattern
What is the most common congenital cardiac defect in dogs?
Patent Ductus Arteriosus
What is the pathophysiology of PDA?
PDA shunts blood from left to right side of heart leading to severe volume overload of left heart and left sided failure
What are the clinical signs of PDA?
Continuous murmur
Hyperkinetic “waterhammer” pulses
What is the treatment for PDA?
Coil embolization
Amplatzer ductal occluder
Surgical ligation
What are the complications associated with PDA?
Severe hemorrhage
Bradycardia
Residual ductal flow
What is the most common cardiac neoplasia in dogs?
Hemangiosarcoma of right auricale
How do you diagnose Hemangiosarcoma of right auricle?
echocardiography
What is the treatment of Hemangiosarcoma of right auricle?
Excision of right auricular mass, pericaardectomy followed by chemotherapy
What are the functions of the pericardium?
Prevents over-distention
Provides gliding surface for heart
Protects heart from spread of infection from thoracic cavity
What do you find on physical exam with Pericardial disease?
Muffled heart sounds
Weak femoral pulses +/- pulsus paridoxicus
What do you see on Electrocardiogram with Pericardial disease?
Electrical alterans
What do you do to diagnose Pericardial disease?
Pericardiocentesis
What is a palliative treatment for cardiac tamponade?
Pericardiectomy
What is the most common persistent right aortic arch?
PRAA with left ligamentum arteriosum
What results from PRAA?
Esophageal constriction/occlusion
What breed is the most commonly affected by PRAA?
German Shepards
What are the clinical signs of PRAA?
Regurgitation
Unthrifty
Respiratory signs secondary to aspiration pneumonia
How would you approach a PRAA?
Left intercostal thoracotomy
How do you surgically treat PRAA?
Isolattion of ligamentum arteriosum
Double ligate and transect
Pass foley catheter and ensure inflated balloon can pass through site of obstruction
What is a long term complication of PRAA?
Aspiration pneumonia
