Surgery of the respiratory tract Flashcards
The trachea is innervated by which nerve?
Right vagus nerve
Which diagnostic methods can be used to investigate the trachea?
- Clinical examination
- Radiography
- Computed Tomography
- Fluoroscopy dynamic assessment
- Trancheobronchoscopy dynamic assessment
- Tracheal wash/bronchoalveolar lavage
Describe the surgical approach to the cervical trachea
- Dorsal recumbency + straight + neck extended over a sandbag
- Ventral midline longitudinal incision from caudal to larynx
- Separate the sternohyoideus muscles – stay on midline
Which structures must be avoided when surgical approaching the trachea?
Segmental blood supply
Recurrent laryngeal nerves
Describe the surgical approach to the thoracic trachea
(very few indications)
- First part: via cervical approach and cranial retraction + cranial median sternotomy
- Median sternotomy or right 3rd to 5th intercostal thoracotomy
REFER
Describe surgical closure of the trachea (materials, pattern etc)
- Absorbable monofilament suture material
- Simple interrupted pattern
- Knots placed extraluminally
- Careful apposition of mucosa + gentle handling for optimal healing
When is a temporary tracheostomy indicated?
- Life-threatening upper airway obstruction
- BOAS
- Laryngeal paralysis
- Laryngeal foreign bodies
- Neoplasia - For GA administration when intra-oral surgery is performed
When is a temporary tracheostomy contra-indicated?
- Obstruction distal to the tracheostomy site
- Tracheal collapse distal to the tracheostomy site
- Previous tracheal stent placement
What equipment is found in a temporary tracheostomy kit?
- Surgical instruments
- Tracheostomy tubes, uncuffed / cuffed
- Large suture material (stay sutures)
- Umbilical tape
Describe the procedure for a temporary tracheostomy
Transverse incision between rings (3-4 or 4-5) should not exceed 50% of tracheal circumference
Describe the management of a temporary tracheostomy
- ICU 24hr monitoring
- Replace tube at least twice daily: once the air isn’t warmed by the URT, the cold air within the trachea increases mucous production for about 16 weeks. Need to keep tubes clean to provide a patent airway
- Suction (few seconds; risk of bradycardia)
- 0.2mL/kg of STERILE saline down the tube q4hrs or nebulise
Why do patients with a temporary tracheostomy require 24hr monitoring?
Tracheostomy tubes can block or dislodge -> suffocation
List the potential complications that can occur following a temporary tracheostomy
- Plugging of tube
- Tube removal
- Gagging, coughing
- Subcutaneous emphysema, pneumomediastinum, pneumothorax
- Infection
- Stenosis
When is a permanent tracheostomy used?
Salvage procedure – unresolvable upper airway obstruction
Tracheal mucosa to skin
- Owners have to be very committed to looking after these patents long term
List the 4 indications for tracheal resection and anastomosis
Trauma
Stenosis
Neoplasia
Avulsion
No more than 5-6 rings
What are the 3 main complications of tracheal resection and anastomosis?
Air leakage
Infection
Stricture
Describe some other conditions of the trachea
Rupture - cats, over inflation of ET tube, subcutaneous emphysema
Avulsion - cats
Hypoplasia - BOAS
Stenosis
Neoplasia - rare
How does tracheal collapse occur?
Laxity of trachealis m. > weakness of rings > collapse
In which patients is tracheal collapse most commonly seen?
Middle-aged small/toy breeds
How would a patient with a tracheal collapse present?
‘Goose-honk’ cough, dyspnoea, exercise intolerance, cyanosis
List the diagnostic methods for tracheal collapse
Signalment
History
Clinical signs
Thoracic radiography
Tracheoscopy
Fluoroscopy
Describe the different grades of tracheal collapse
Grade 1 = laxity of the dorsal tracheal membrane, 25% luminal collapse
Grade II = loss of cartilage rigidity and further laxity, 50% luminal collapse
Grade III = flattening of the cartilages, 75% collapse
Garde IV = 100% loss of luminal integrity
How can tracheal collapse be managed medically?
- Corticosteroids (anti-inflammatory) - Oral or inhaled
- Anti-tussives
- Bronchodilators
- Antimicrobials: if infection, choose based on BAL if possible
- Weight loss
- Exercise control: harness
Describe the emergency management of a patient with tracheal collapse
- Oxygen
- Sedatives
- Corticosteroids
- Intubate
- Check if correction of laryngeal paralysis/collapse or staphylectomy needed
How is tracheal collapse treated surgically?
Extraluminal prosthetic tracheal rings
Intraluminal stenting
List some complications of tracheal collapse surgery
- Stent fracture
- Stent migration
- Inflammatory tissue
- Necrosis
Describe an intercostal thoracotomy
- Access to R or L thorax
- Cannot access structures away from incision
Describe a median sternotomy procedure
Bilateral exploration of the thoracic cavity
Preserve manubrium or xyphoid if possible
List the 4 indications for a lung lobectomy
Total or partial lobectomy
- Lung lobe torsion
- Localised pulmonary abscess, cyst, bulla, neoplasia
- Severe lung trauma
- Broncho-oesophageal fistula
What are the 3 main aims of managing a patient with thoracic trauma (RTA, bite wound, fall, etc)?
- Maintain a patent airway, provide oxygen
- Support circulation – iv access - fluids
- Control obvious haemorrhage
List the 7 common injuries associated with thoracic trauma
- Pulmonary contusions
- Pneumothorax
- Rib fractures
- Open thoracic wounds
- Haemothorax
- Diaphragmatic rupture
- Shock
What should be assessed when examining a patient with thoracic trauma?
- Respiratory rate and pattern
- Mucus membrane colour and CRT
- Auscultation and percussion of thorax
- Observation of thoracic outline
- Check for evidence of wounds
- Minimise patient stress
Which diagnostic tests would you want to perform in a patient with thoracic trauma?
- Haematology, serum biochemistry
- Radiography: thoracic (lateral/DV, not VD!), abdominal
- Thoracocentesis if pleural air or fluid
Describe how to treat rib fractures
- Often incidental findings on radiographs
- Suspect pulmonary contusions present if recent trauma
- Conservative management usually adequate
- Analgesia
- Rest
- Oxygen supplementation
Describe a flail chest
- Segment of one or more ribs is fractured in two planes
- This segment can move independently from chest wall
- Paradoxical movement compromises respiration
What is a diaphragmatic hernia?
Direct or indirect injury > abdominal organs enter pleural space
List the organs involved in a diaphragmatic hernia from most to least likely
Liver; SI > stomach > spleen > omentum > pancreas > colon > coecum > uterus
Describe the signs presented with a diaphragmatic hernia
Pleural effusion
Respiratory and gastrointestinal signs
Exam: normal? Empty abdomen? Muffled heart sounds? Borborygmi on auscultation?
Describe surgery for a diaphragmatic hernia
- Surgery when the patient is stable!
- Surgery asap if stomach herniated: needle decompression to reduce gas expansion
- Chronic consider no treatment ?
- Gradual re-expansion of lungs, otherwise reperfusion injury and pulmonary oedema
- Diaphragmatic closure: PDS (absorbable monofilament) in a simple continuous +/- interrupted pattern
Describe loss of domain during diaphragmatic hernia surgery
Suddenly too much content within the abdomen – may need to consider splenectomy
