Ch 103 Lungs Flashcards
List the muscle that cover the thoracic wall from internal to external
Serratus dorsalis and ventralis
Scalenus
External abdominal oblique
Latissimus dorsi
pectoralis
Cutaneous trunci
intercostal vessels
- An intercostal nerve, vein, and artery are located caudal to the cranial rib in each intercostal space
- arteries arise directly from the aorta and anastomose with the internal thoracic arteries.
List the lung lobes
Left:
- Left cranial (subdivided into cranial and caudal)
- Left caudal
Right:
- Cranial
- Middle
- Caudal
- Accessory (located medial to the plica vena cava)
Where are the pulmonary arteries and vein located in relation to the associated bronchus?
Artery: craniodorsal
Vein - Caudoventral
Ventilation
- requires input from the brain respiratory centers, spinal cord, peripheral nerves, respiratory muscles and the presence of negative pressure in the pleural spaces (coupling between the lung and the thoracic wall)
- Air is moved following a pressure gradient.
- inspiration, pressure in the alveoli is subatmospheric > air to move in to the alveoli.
- During inspiration, ventilation has to overcome tissue elastance, alveolar surface tension, and airway resistance.
- Elastance = degree to which the lung can return to its dimensions (recoil)
- Compliance = measure of lung distensibility
- Alveolar surface tension normally is low because of surfactant produced by alveolar type II cells
- Surfactant indirectly increases lung compliance by lowering surface tension
- Airway resistance must also be overcome during inspiration and expiration (i,e, nares, larynx)
- Alveolar ventilation is precisely controlled to match metabolic need; therefore, arterial pressure of oxygen (PaO2) and arterial pressure of carbon dioxide (PaCO2) vary minimally
- A portion of that ventilation is alveolar (critical for gas exchange)
- remainder is dead space, which is important for other functions such as thermoregulation
What controls ventilation?
- Chemoreceptors in respiratory centre in medulla (tidal volume and rhythm)
- Peripheral chemoreceptors in carotid and aortic bodies (CO2 stimulates)
- Stretch receptors in the airway and lung parenchyma stop inspiration (to prevent overinflation)
What structures contribute to inspiratory resistance and expiratory resistance?
Inspiratory:
- Nares 79%
- Small airways 15%
- Larynx 6%
Expiratory:
- Nasal 74%
- Laryngeal 3%
- Small airways 23%
PaO2, PaCO2
aveolar ventilation
- Changes in PaO2, PaCO2, and pH stimulate central and peripheral chemoreceptors
- small increase in PaCO2 causes a substantial increase in ventilation, which returns PaCO2 to original levels
- CO2 can diffuse through the blood-brain barrier. When dissolved in the extracellular fluid, CO2 is converted to HCO3− and H+, which stimulate the central receptors
- CO2 also stimulates peripheral receptors in carotid and aortic bodies
- If PaO2 is below 60 mm Hg, however, ventilation increases
Alveolar ventilation determines the amount of CO2 in arterial blood: when PaCO2 is increased, hypoventilation is present; conversely, when PaCO2 is decreased, hyperventilation is present.
What is hypoxic ventilation drive?
An increase in ventilation is PaO2 is below 60mmHg
What muscles can be engaged to aid inspiration and expiration?
Inspiration:
- external intercostal
- sternocleidomastoid
- scalenus
- serratus ventralis
Expiration:
- Internal intercostals
- Abdominal rectus
What can alter lung complicance?
Fibrosis
Oedema
What cells produce surfactant?
What is its function?
Alveolar type II cells
Indirectly increases lung compliance by reducing surface tension
Prevents collapse of small alveoli
Gas Diffusion Across the Blood-Gas Interface
follows Fick’s law
The rate of transfer of a gas through a sheet of tissue is proportional to the surface area available for diffusion, diffusion coefficient of the gas, difference in gas partial pressures and inversely proportional to the tissue thickness
- diffusion coefficient of CO2 is 20 times greater than that of oxygen; CO2 therefore diffuses more rapidly
- area for diffusion decreases and the diffusion distance increases, resulting in reduction of oxygen saturation (hypoxemia) well before CO2 removal is inadequate (hypercapnia)
Gas Transport by Blood
- Oxygen is transported in a dissolved state or in combination with hemoglobin (Hb)
- most of the oxygen delivered to the peripheral tissue (98.5%) is bound to hemoglobin
- Oxygen forms a reversible combination with hemoglobin to produce oxyhemoglobin
- Oxygen saturation of arterial blood with a PaO2 of 100 mm Hg is approximately 97.5%
oxygen-hemoglobin dissociation curve
- describes the interaction between dissolved oxygen and heme
- sigmoid form
- flat upper portion means that a decrease in partial pressure in alveolar gas will have little effect on oxygen saturation when oxygen partial pressure is 80 mm Hg or more
- oxygen diffuses along a positive-pressure gradient from the alveoli to capillary blood, oxygen reserve is large enough for sufficient oxygen to diffuse into the blood and saturate hemoglobin.
- steep part of the dissociation curve means that the peripheral tissues can withdraw a large amount of oxygen
- A rightward shift allows better unloading of oxygen, which is beneficial in peripheral tissue.
What can cause the oxygen dissociated curve to shift to the right?
decreased affinity thus better unloading of O2
Increased temp,
increased PCO2,
increased 2,3-DPG diphosphoglycerate in RBCs
Decreased pH
Arterial oxygen content
- PaO2 refers to the partial pressure of oxygen in the arterial blood, a measurement of the pressure of oxygen dissolved in the blood, typically obtained through an arterial blood gas (ABG) test.
- PaO2 reflects how effectively oxygen moves from the lungs into the bloodstream.
- PaO2 is influenced by the pressure of inhaled oxygen (FiO2), PaCO2, and lungs
- PaO2 is a major determinant of Os saturation, which is the percentage of available binding sites on hemoglobin that are bound with oxygen.
- Arterial oxygen CaO2 = (1.36 × Hb × %O2Sat/100) + 0.003 PaO2
- acute blood loss results in reduced oxygen-carrying capacity (reduced Hb), so transfusions important
Forms of carbon dioxide (CO2) transport in the blood
CO2 is carried in the blood in:
1. dissolved form (~5% of transported arterial CO2)
2. chemical combination with proteins hemoglobin as carbamino compounds (~20% of excreted CO2)
3. majority is transported in the form of bicarbonate
Within RBCs, carbonic anhydrase accelerates transformation of CO2 into carbonic acid, which dissociates into bicarbonate and hydrogen ions.
- The reaction continues to move to the right because hemoglobin buffers the hydrogen ion.
- In the lungs, CO2 is removed with ventilation, decreasing PaCO2 and reversing the effect.
- Hemoglobin oxygen saturation has a major effect on CO2 dissociation because deoxygenated hemoglobin has a greater affinity for CO2 than oxyhemoglobin.
- Deoxygenated (venous) blood therefore transports more CO2 than oxygenated blood
Gas Exchange
- collective process by which O2 and CO2 are exchanged between the alveolar gas and the arterial blood
- dependent on the relationship (or matching) of ventilation to perfusion
- adequate exchange between alveoli and arterial blood in the capillaries, flow of blood (Q) and ventilation of the alveoli (V) have to match, in a ratio (V/Q) equal to 1.
What can cause a high V/Q and a low V/Q
High V/Q - PTE
Low V/Q - atelectasis, pneumonia, severe pulm oedema
Hypoxaemia definition
causes (5)?
arterial oxygen saturation less than 90%
- hypoventilation (increase in PaCO2)
- low fraction of inspired oxygen (increase CO2)
- diffusion impairment (increased thickness or decreased surface area > emphysema, pulmonary interstitial fibrosis, and early pulmonary edema)
- ventilation-perfusion (V/Q) mismatch (PTE, oedema etc)
- shunting/Venous admixture (right-to-left shunt in the heart)
Ventilation-perfusion mismatch or V/Q mismatch
- (A-a) gradient helps quantitate the degree of V/Q mismatch
- Partial pressure of oxygen in the arterial blood (PaO2) should be nearly equal to alveolar oxygen pressure (PAO2) and should approach 100 mm Hg at sea level under normal physiological conditions.
- V/Q mismatch = PaO2 < PAO2
- PAO2 = [FIO2 × (Pbarometric − PH2O)] − [1.2 × PaCO2], with FIO2 = fraction of inspired oxygen (21% on room air) and PH2O = 47 mm Hg at the level of the alveoli.
- Alveolar-arterial O2 difference, PA-aO2 = PAO2– PaO2
- normal room air respiration: PA-aO2 should be <10mmHg
- PA-aO2 >30mmHg = severe gas exchange impairment
- supplementation recommended at PA-aO2>20mmHg
Animals with increased V/Q have a good response to oxygen.
Low V/Q hav poor reponse and shunts have no response
Consequences of Thoracotomy on Pulmonary Physiology
Hypoxemia (low PaO2)
- reduced ventilation, diffusion impairment, and V/Q mismatch
- hypoventilation may be the result of anesthetic drugs, opioids, pain, or residual pneumothorax
- Atelectasis contributes to hypoxemia
- undergone intercostal thoracotomy should be recovered in lateral recumbency, laying on their surgical side (dependent side become non-dependent)
Residual Pneumothorax or Pleural Effusion
- interfering with lung reexpansion and ventilation.
- Thoracostomy tube placement is paramount for postoperative lung reexpansion.
Pain
- Pain prevents full thoracic wall excursion > reduced ventilation > hypoxemia
- analgesics, especially opioids, have a significant depressant effect on the respiratory center.
- intercostal nerve block facilitate postoperative pain control without affecting ventilation
Postoperative Monitoring
- optimize oxygen delivery (cardiac output and arterial oxygen)
- Heart rate, arterial pressure, central venous pressure, and urine production are monitored
- vetilation: Blood gases and lactate concentration
- Supplemental oxygen if the arterial oxygen saturation <93% - 95% and/or if the PA-aO2 is >20 mm Hg
What are common post-op problems to monitor for after a thoracotomy?
Hypotension
Hypothermia
Hypoventilation
Electrolyte imbalance
Shock
Surgical Approaches (3)
Intercostal Thoracotomy
- allows access to approximately one-third of the ipsilateral thoracic cavity and mediastinal structures.
- radiograph can help determine the intercostal space that best
- hilus of the lungs is located between the fourth or fifth intercostal space
- thoracostomy drain is placed to establish negative intrapleural pressure and monitor the pleural space
Median Sternotomy
- allows access to the entire thoracic cavity
- great vessels and bronchial hilus, are more difficult,
- manubrium, xiphoid, or both should be left intact.
- In dogs, pain, the degree of cardiopulmonary impairment, and complication rates with this approach are not different from those after intercostal
Thoracoscopy
- minimally invasive
- surgical telescope, trocar-cannulas, a set of thoracoscopic surgical instruments, a light source, a video camera, and a video monitor.
- Thoracoscopy does not require CO2 insufflation
- performed through a transdiaphragmatic (subtotal pericardiectomy) or an intercostal approach (Lung lobectomy)
- Cannulas should be inserted in the ventral two-thirds
What are the two thoracoscopic options?
Intercostal (4th-9th ICS)
Transdiaphragmatic (Manubrium, 9th-10th ICS)
Congenital Diseases of the Lungs
- Hypoplasia of one lung or lung lobe
- tracheoesophageal and bronchoesophageal fistulas
Cysts, Bullae, and Blebs
- Cysts within parenchyma can be fluid filled or air filled and are covered by a respiratory epithelium
- Blunt trauma to the chest with pulmonary contusion seems to be the most common cause
- Lung bullae and blebs (pseudocysts) have no epithelial lining
- Bullae are large and develop within parenchyma, and blebs are small between the parenchyma and visceral pleura
- develop from traumatic rupture and coalescence of alveoli and are frequently secondary to obstructive lung disease
- Bullae and cysts show similar complications of infection; abscessation; rupture, resulting in pneumothorax
- may be underlying cause of Spontaneous idiopathic pneumothorax
- sensitivity of CT scan is very poor (42% to 58%) for the diagnosis of the cause of a spontaneous pneumothorax
- Conservative management by continuous intrathoracic drainage can be attempted for 2 to 3 days before partial or complete lobectomy is considered
- Most dogs have lesions in the cranial lung lobes
- bulla or bleb cannot be visualized, the thorax is filled with warm saline so that leaks can be identified
What imaging technique can be used for diagnosis of bronchoesophageal fistula?
What breeds are overrepresented?
Contrast oesophogram with water soluble iodine
Toy-breeds and small terriers
- primarily result from foreign bodies wedged into the esophagus
- lung lobectomy and fistula closure.
What bacteria are most commonly isolated from lung lobes abscesses?
E.Coli
Klebsiella pneumoniae
Staph
Strep
Pseudomonas
Fusobacterium
Consolidated Lung Lobe and Abscess
- Consolidated lung lobe: from pneumonia secondary to a foreign body, bacterial or fungal infection, or parasites
- Abscesses: thoracic penetrating wounds, vascular obstruction, or central necrosis of a pulmonary neoplasm > commonly result in pyothorax
- plant awn frequently migrates into parenchymal
- Thoracic radiographs aid in locating the involved region > alveolar pattern with air bronchogram
- CT has been used to identify pulmonary foreign bodies
Tx
- Bronchoalveolar lavage should be performed to collect fluid from the diseased lung for cytology, culture, and sensitivity.
- Appropriate antibiotics are administered for at least 2 to 3 weeks
- pleural effusion is present, a thoracostomy tube
- sternotomy is the approach of choice because it allows evaluation of both sides
- partial or complete lobectomy is performed
- if chronic restrictive pleuritis is present and prevents lung reexpansion > lobectomy
- mortality rate was 20%
What is the maximum volume of lung which can be acutely removed?
50%
What is the surgical outcome after lung lobectomy for lung abscess?
- Mortality 20% (14% if 1 lobe removed, 60% if three removed)
- 54% of survivors has resolution of their pneumonia
- MST 96m with resolution of pneumonia vs 10m
Bronchiectasis
- localized or diffuse destructive lung disease that results in severe dilatation of large airways, accumulation of secretions, and recurrent infection
- inflamed bronchial walls lose collagen and elastin elements, and a granulomatous reaction develops
- manifests grossly as a prominent lump in the lungs. It induces atelectasis
- can be associated with primary ciliary dyskinesis or be the result of chronic respiratory disease
- prognosis is guarded; the median survival time of dogs treated for bronchiectasis is 16 months
Lung Laceration
- Blunt (rib fracture) or penetrating trauma> subsequent pneumothorax
- lateral compression of the chest wall with a closed glottis, resulting in a rapid increase in airway pressure
- iatrogenic
- thoracic radiographs, patients with lung lacerations have pneumothorax
Conservative Treatment
- initial treatment of choice
- Small lung lacerations usually resolve with the aid of thoracic drainage
- supplemental oxygen delivery via cage, mask, or nasal
- blood patch
Sx
- If intrapleural air does not resorb in 3 to 4 days, surgery is indicated
- Median sternotomy
- leaks can be detected by flooding the chest with warm sterile saline under IPPV
- Lacerations are closed with a mattress pattern of absorbable 4-0 or 5-0 suture (interrupted Lembert)
- mounted on Teflon pledgets to provide an adequate seal without tearing tissue
- partial lung lobectomy
- mainstem bronchus), the airway can be reapposed with simple interrupted sutures
- thoracostomy tube
Lung Lobe Torsion
- large deep chested: lung lobe torsion can be spontaneous or occur secondary
- Pugs, the condition is thought to be spontaneous
- cause poorly understood but may result from partial collapse of the lung lobe, permitting increased mobility
- lobe subsequently becomes severely congested and consolidated as fluid moves into the interstitial tissue and airways
- Dogs can have an acute or chronic presentation
- thoracocentesis is usually serosanguineous or chylous
dx
- RADS: Pleural effusion and lung consolidation
- Changes in bronchial size are more readily noted on CT, all have abrupt terminations
Tx
- Initial therapy is symptomatic and aimed at stabilization.
- Lobectomy
- To avoid release of inflammatory cytokines and endotoxins, they should not be untwisted.
- Stapling equipment is preferred because it permits lobectomy with the lung in its torsed position
- fair to guarded after lobectomy, with a survival rate of 50%
- more favorable prognosis noted in Pugs
What breeds are predisposed to lung lobe torsion?
- Large dogs with deep narrow chests (right middle and left cranial)
- Pugs (left cranial)
- May be assoc with chronis resp disease, chylothorax, trauma, d-hernia, thoracic surgery, neoplasia
Pulmonary Neoplasia
- Most primary lung tumors are malignant
- respiratory dysfunction from lung infiltration or airway compression
- Pulmonary hemorrhage or pneumothorax may occur with vessel or airway erosion
- Primary or mets: develop hypertrophic osteopathy (paraneoplastic syndrome)
- Cats can have “lung-digit” syndrome
dx
- Cats may have diffuse or multifocal primary lung tumors.
- hilar lymph nodes should be evaluated on radiographs and CT
- false-positive and false-negative result possible on CT
- Complication rates after fine-needle lung aspiration include pneumothorax, hemoptysis, and death (reduced if ultrasound guided)
- large neoplastic masses that affect the lobe periphery or the entire right middle or left cranial lung lobe > histiocytic sarcomas
Sx
- considered in animals with primary or metastatic neoplasia of the lung if the mass is a solitary
What is the most common type of pulmonary neoplasia?
What conditions can be seen with pulmonary neoplasia?
Carcinomas of bronchial or alveolar origin
Hypertrophic osteopathy or lung-digit syndrome (17.9% of cats)
What should be used for lung FNA?
What is the diagnostic rate?
22-25g needle under u/s guidance
DIagnostic in 80% (sen 77%, spec 100%)
What factors are associated with prognosis for pulmonary neoplasia
- Clinical signs (545 vs 240d)
- LN involvement (452 vs 26d)
- Better prognosis for solitary, well-differentiated carcinoma less than 5cm in diameter
- Malignant pleural effusion worse prognosis
- SCC worse prognosis (50% survival 8m)
In cats, degree of differentiation most prognostic
- moderately differentiated 698d
- poorly differentiated 75d
How should you suture a partial lung lobectomy?
Continuous overlapping haemostatic, pneumostatic suture pattern (1-2 layers)
Oversewn with simple continuous
If relatively large bronchi and blood vessels are encountered, they are ligated individually
Partial Lobectomy
- distal two-thirds or less
- sutured
- stapled (TA)
- Thoracoscopic (Endo GIA)
- keyhole ( 3- to 7-cm intercostal thoracotomy)
What stapler can be used for partial lung lobectomy?
Endo-GIA
- 30-, 45- and 60mm cartridges
- Open staple leg lengths 2.0, 2.5, 3.5, 4.8
- 2.5mm staples typically used for partial lung lobectomy
- Can be inserted through a 12mm cannula
Total Lung Lobectomy
- ## preferred open surgical approach through a lateral intercostal thoracotomy
What structure needs to be broken down for a caudal lung lobectomy?
Pulmonary ligament (pleural fold between the caudal edge of the hilus and the mediatinum)
suture ligation lobectomy
- The arterial supply to the lobe is approached first
- triple ligated with two encircling sutures and one transfixation
- pulmonary vein is approached on the ventral or caudal side of the bronchus
- bronchial suture line is tested for air leaks, uturing surrounding pleural and subpleural tissue over the end of the bronchus
How should a mainstem bronchus be ligated?
Pre-placed horizontal mattress sutures
Oversewn
What staplers can be used for total lung lobectomy?
TA-V3
TA55 with 3.5mm staples
In which dogs is an open thoracotomy recommended for lung lobectomy over thoracoscopic?
Dogs weighing less than 10kg
Mass over 8cm
Three or four cannulas are required. If a cranial lung lobe is removed, cannulas are placed in the eighth or ninth intercostal space; if a caudal lung is resected, cannulas are placed in the fourth intercostal space.
bag (e.g., EndoPouch) to facilitate retrieval of the specimen without thoracic wall contamination.
complications
cardiac arrest
haemothaorax
pulmonary hypertension
pneumothorax
incisional dehiscence
Removal of what % of lung if fatal?
What % volume is within the left and right lung?
- Removal of 60% is fatal (acute pulmonary hypertension) - should remove a maximum of 50% acutely
- Left lung 42%
- Right lung 58%
Dogs undergoing staged lobectomies over 6m period can survive with equivalent of 1.5 caudal lung lobes
can do left but not right actuely
What changes are seen in the contralateral lung and myocardium after a pneumonectomy?
- Decreased compliance, vital capacity and perfusion
- Right ventricular hypertrophy and increased pulmonary vascular resistance and residual lung capacity
What causes compensatory improvement of oxygen transport after over 50% pneumonectomy?
- Recruitment of physiologic reserves of diffusion capacity
- Remodelling of existing alveoli-capillary structures
- Growth of new alveoli-capillary unit
pneumonectomy
- Control of the branch of the main pulmonary artery (lobar artery) early reduces the chance of major hemorrhage
- Lobar arteries 5 mm or larger should be stapled or oversewn
- endotracheal tube cuff is deflated, the tube is advanced into the contralateral bronchus
- first suture line is placed approximately 5 to 10 mm distal to the carina
Short-term outcomes of dogs and cats undergoing
lung lobectomy using either a self-ligating loop
or a thoracoabdominal stapler
sandoval 2024
Retrospective study.
Animals: A total of 72 dogs and 15 cats.
TA stapler was
used in 83 (82.2%) and the SLL in 18 (17.8%) lung lobectomies. Intraoperative
complications were identified in 14/101 lung lobectomies (13.9%), including
intraoperative hemorrhage in 12/101 lobectomies (11.8%) and air leakage in
2/101 lobectomies (1.9%). Postoperative complications were identified in 12/87
cases (13.8%), including 4 (4.6%) catastrophic complications and 5 (5.8%) major
complications.
Self-ligating loop lung lobectomy provided a comparable
alternative to stapled lung lobectomy. Further studies are needed to assess
technique superiority.
The SLLs improved resistance to airway leakage likely
correlates with improved resistance to hemorrhage.
Thoracoscopic resection of lung masses
is associated with excellent survival
to discharge and good long-term outcomes
Karen Park 2024
mayhew
61 client-owned dogs.
(81%) were carcinomas. Clean surgical margins were achieved in 46 of 52 (88%) dogs
Conversion to open surgery occurred in 16 of 61 (26%) dogs > Larger tumor diameter (≥ 5 cm) risk factor
All 61 dogs survived to discharge, and 56 of 57 were alive 1 month postoperatively. Median overall survival time was 311 days
Tracheobronchial lymphadenopathy associated with shorter survuval, margins chemo were not.
(85%) cases, one-lung ventilation (OLV) was used.
Intraoperative complications occurred in 10 of 61 (16%) dogs. Hemorrhage, iatrogenic tear, leakage
Postoperative complications occurred in 5 of 61 (8%) dogs
Reasons for conversion (more than 1 reason given for some cases) included the following: mass judged to be too large (n = 6), failure of or difficulty maintaining OLV (3), poor visualization (3), presence of adhesions (2), OLV not tolerated (1), surgical stapler unable to be opened in the thorax (1), intercostal artery bleed (1),
A prospective randomized study would be required to provide higher-level evidence to compare open and minimally invasive approaches for lung lobectomy
Fluoroscopy-guided fine-needle aspiration
of deep-seated pulmonary masses in dogs and cats appears safe and accurate
Frédéric Jacob 2024
Client-owned animals; 5 dogs and 5 cats
Exfoliative cytology results were consistent with carcinoma in 4 dogs and lymphoma in 1 dog. A minor postprocedural complication was noted in 1 dog
Clinical characteristics and
long-term outcome of lung lobe
torsions in cats: a review of 10
cases (2000–2021)
Catherine Tindale 2022
cinti
Pleural effusion was present in nine cats at presentation.
Fluid analysis confirmed chylothorax in three cats
A diagnosis was made preoperatively in six cats
Lung lobectomy was successfully performed in all cases. Based
on clinical, diagnostic and lung histopathology findings, three cats had idiopathic and seven cats secondary LLT
Postoperative
complications occurred in six cats and lead to euthanasia or death in four cats
Secondary LLT associated with underlying thoracic pathology was associated
with high complication rates and poor outcomes.
(effusions, carcinoma)
Most reported LLTs in cats are of secondary aetiology
(67%),2,5,7–18 in contrast to in dogs (24–38%).1,6,24
Lee 2020 – proposal of canine lung cancer stage classification (CLCSC) for primary pulmonary
carcinoma
- MST overall 370d; tumour specific survival 493d
- staging correlated with survival: I 7/71 MST 952d; II 32/71 MST 658d;
III 24/71 MST 158d; IV 8/71 MST 52d
- primary tumour features (T1-4
), incomplete excision, LN metastasis and tumour grade
independent px indicators for survival
- no statistically significant benefit for adjuvant chemotherapy
McPhetridge 2022 – incidence of primary pulmonary neoplasia and outcomes in dogs
perioperative mortality 20/340 (5.9%)
- pulmonary carcinoma 296/340 (87.1%) - MST 399d
- 27.0% developed metastasis, 6.1% developed recurrence
- MST by stage: I 663d; II 389d; III 361d; IV 273d
- when sorted by clinical stage – adjuvant chemotherapy → no difference in MST
- sarcoma 26/340 (7.6%) - histiocytic sarcoma MST 300d
- adenoma 11/340 (3.2%)
- pulmonary neuroendocrine tumour 5/340 (1.5%) - MST 498d
- prognostic for survival: primary tumour size >5cm, pleural effusion, increasing mitotic
count, distant metastasis, affected lymph nodes
Thoracic CT incidental pulmonary bullae in dogs:
Characterization, interobserver variability, and general
anesthesia risks
Won Suk Kim 2023
VRU
74 dogs were included in analyses
No adverse anesthesia events were
found following CT anesthesia or following repetitive anesthesia procedures.
Lung lobe torsion in 15 dogs: Peripheral band sign
on ultrasound
CT is helpful for the detection and presurgical planning of lung
perforation in dogswith spontaneous pneumothorax induced
by grass awn migration: 22 cases
VRU
The perforation site was identified in 21 of 22 (95.5%) dogs and involved
the caudal lobes in 20 of 22 (90.9%) cases
The perforation site was characterized as a
soft tissue attenuating focus lying against an extensive pleural thickening in 21 of 22(95.5%) dogs.A grass awn was seen
in 11 of 22(50%) dogs. The pneumothorax distribution and grass awn position consistently indicated
the perforation side in this sample of dogs.
Bronchoscopic findings in dogs
with bronchial vegetal foreign bodies:
84 cases (2010-2020)
J. Flageollet 2023
Mild bleeding was the main complication (58 of 75; 77%) of endoscopic removal, which was successful in 67 of the 84 (80%) cases.
Prevalence of bronchial wall thickening and collapse
in brachycephalic dogs with and without brachycephalic
obstructive airway syndrome and in nonbrachycephalic dogs
James S. Guillem
,Bronchial collapse was also more common in dogs with brachycephalic conformation, which is in agreement with the previously published literature.
Cavitary pulmonary lesion wall thickness, presence of additional nodules, and intralesional contrast enhancement are associated with malignancy in dogs and cats
Megan E. Parry 2023
lesions that have heterogenous contrast enhancement, additional pulmonary nodules, and wall thickness > 40 mm at their thickest point, it would be reasonable to consider malignant neoplastic disease higher
Complications and outcomes of thoracoscopic-assisted lung
lobectomy in dogs
Jacqueline E. Scott 2023
Multi-institutional, retrospective study.
Animals: Client-owned dogs (n = 30).
Twelve intraoperative complications were recorded in 11 dogs, 6
requiring conversion to open thoracotomy. Reasons for conversion were
reported in 5/6 dogs and included adhesions (2), difficultly manipulating the
lesion through the mini-thoracotomy (2), and acute oxygen desaturation (1).
One lung ventilation was successful in 4 of the 7 dogs
(27%),post complications
1 dog dies thromboembolic event
Death was reported in 9 dogs, with a median
survival time of 168 days
Thoracoscopic-assisted lung lobectomy may be considered
to facilitate the excision of larger pulmonary lesions or to treat smaller
dogs, in which a thoracoscopic excision may be technically more challenging.
Evaluation of long-term outcome after lung lobectomy
for canine non-neoplastic pulmonary consolidation
via thoracoscopic or thoracoscopic-assisted surgery
in 12 dogs
Amy C. Downey 2023
Nine patients underwent a TL approach and 3 underwent TAL. In
those that underwent TL, conversion to an intercostal thoracotomy was performed
in 4 out of 9 dogs
1 died
Conversion rates were higher than those historically
reported for dogs undergoing thoracoscopic lung lobectomy for primary lung
tumors.
Anatomical considerations for the surgical approach to the
canine accessory lung lobe
Alastair J. Mather 2023
Cadaveric anatomical study.
The lateral vein varied in its location, The pulmonary ligament attached to the ALL in a
caudally pointing apex on the dorsal process of the lobe. Medial and lateral
extensions of the ALL parenchyma were found.
The ALL was most easily accessed by a right lateral thoracotomy at the sixth intercostal space
Surgical management and outcome of dogs
with primary spontaneous pneumothorax:
110 cases (2009–2019)
Rachel Dickson 2021
(90%) dogs underwent median sternotomy,
Recurrence was significantly more likely to occur ≤
30 days after surgery, recurrecnt rate 3%
Lung lobectomy via median sternotomy resulted in resolution of pneumothorax
in most dogs with primary spontaneous pneumothorax
2-year and 5-year survival rates
were 90%.
reflected failure to identify lesions during the initial
thoracic exploration, rather than development of additional bullae.
Failing to divide the xiphoid may severely
limit the surgeon’s ability to visualize the entirety of
the accessory lung lobe,
Long-term survival after treatment of idiopathic lung
lobe torsion in 80 cases
Matteo Rossanese 2020
Retrospective multicenter study from four veterinary teaching
hospitals.
Animals: Dogs (n = 80) with LLT.
pugs (47.5%
considered primary in 77%, secondary in
21%, and unknown in 2% of dogs.
Postoperative complications were recorded
in 14% of dogs. Overall, 95% of dogs survived to discharge
Primary LLT was associated
with a longer survival (median not reached in the study) compared with
secondary LLT (921 days
Six (11%) dogs died or were euthanized for causes
related to their secondary LLT, four for chylothorax, one
for pulmonary carcinoma, and one for mesothelioma
Dogs with primary LLT undergoing lung lobectomy have a
longer survival time compared with dogs with secondary LLT and have an
excellent postoperative outcome.
Percutaneous microwave ablation of solitary presumptive
pulmonary metastases in two dogs with appendicular
osteosarcoma
Josephine A. Dornbusch 2020
Percutaneous MWA of pulmonary nodules was technically feasible
in two dogs without major complications
Liptak et al9 reported a median survival time of
487 days for 36 dogs that underwent limb amputation,
single-agent cisplatin therapy, and lung lobectomies to remove metastatic lesions.
Long-term clinical outcomes following
surgery for spontaneous pneumothorax
caused by pulmonary blebs and bullae in
dogs – a multicentre (AVSTS Research
Cooperative) retrospective study
C. L. Howes 2020
Two- and 5-year survival rates were 88.4% and 83.5%, respectively. There was recurrence
in 14 of 99 dogs (14.1%)
Use of a novel vessel-sealing device for peripheral lung biopsy and lung lobectomy in a cadaveric model
M. Brückner 2019
None of the samples leaked below 25 cm H2O, which is well above the physiologic airway pressure.
extent of collateral damage was approximately 2.7 mm in all specimens.
The maximum physiologic airway pressure is considered to be
20 cm H2O (Santini et al. 2006). Currently partial lung lobectomy
is routinely performed with staplers, resulting in median leak pressures
of 25.5 cm H2O for thoraco-abdominal-stapled biopsies
Evaluation of a pre-tied ligature loop for canine total lung
lobectomy
Anna M. Cronin 2019
Sample population: Thirty cadaveric canine lung lobes and 5 client-owned dogs.
endoloop
Results: Two stapled and 4 sutured bronchial stumps leaked at supraphysiological
pressures >15 mm Hg. One stapled bronchial stump failed at a physiological airway
pressure (5 mm Hg). None of the PLL lobectomies leaked. The incidence of bronchial
stump failures did not differ among techniques (P = .15). Lung lobectomy was
performed successfully with the PLL in 5 clinical cases with no intraoperative or
postoperative complications; median follow-up time was 6 months.
