AIRWAY Flashcards
What are the intrinsic muscles of the larynx?
Cricothyroid, Vocalis, Thyroarytenoid, Lateral Cricoarytenoid, Posterior Cricoarytenoid, Aryepiglottic, Interarytenoid
These muscles are responsible for vocal cord tension, length, and position.
What is the function of the cricothyroid muscle?
Tenses and elongates the vocal cords by tilting the thyroid cartilage
Innervated by the external branch of the superior laryngeal nerve.
Which intrinsic muscle is responsible for adjusting tension in the vocal cords?
Cricothyroid and Thyroaryntenoid such as the Vocalis Muscle,
It is part of the thyroarytenoid muscle and is innervated by the recurrent laryngeal nerve.
What is the function of the thyroarytenoid muscle?
Relaxes and shortens vocal cords, aiding in voice modulation
Innervated by the recurrent laryngeal nerve.
True or False: The posterior cricoarytenoid muscle is the only abductor muscle of the vocal cords.
True
Its dysfunction can lead to vocal cord paralysis.
What is the primary function of the lateral cricoarytenoid muscle?
Adducts vocal cords, narrows the rima glottidis
Important in producing vocal sounds and airway protection.
What are the unpaired cartilages of the larynx?
Thyroid Cartilage, Cricoid Cartilage, and epiglottis
Thyroid cartilage is the largest, while cricoid cartilage forms the base of the larynx.
What is the function of the arytenoid cartilages?
Critical in vocal cord movement and voice production
They are small, pyramid-shaped, and paired.
What role does the trigeminal nerve (Cranial Nerve V1) play in airway innervation?
Innervates the anterior two-thirds of the nasal cavity and nasal septum
Provides sensation to the anterior part of the nasal mucosa and soft palate.
Which cranial nerve is primarily responsible for the afferent aspect gag reflex?
Glossopharyngeal Nerve (Cranial Nerve IX)
It also carries taste sensation from the posterior third of the tongue.
What does the superior laryngeal nerve innervate?
Provides sensory innervation to the larynx above the vocal cords and motor innervation to the cricothyroid muscle
Injury can lead to changes in voice pitch and difficulty in swallowing.
What are the symptoms of unilateral vocal cord paralysis?
Hoarseness, ineffective cough, aspiration risk
Caused by damage to one recurrent laryngeal nerve.
Fill in the blank: The Mallampati classification was developed by Dr. _______.
Seshagiri Mallampati
It is a non-invasive test to assess airway management challenges.
What does a higher Mallampati score indicate?
Increased difficulty in intubation
Specifically, scores III and IV are associated with more challenges.
What is the significance of the thyromental distance in airway management?
Guides selection of intubation tools and techniques
A shorter distance may indicate a difficult airway.
What does an adequate inter-incisor gap suggest?
Normal jaw mobility, facilitating easier laryngoscopy and intubation
Adequate gap is ≥3-4 cm.
What does Class C indicate in the mandibular protrusion test?
Lower incisors cannot reach the edge of the upper teeth, indicating potentially difficult intubation
Class A indicates easy intubation, while Class B suggests intermediate difficulty.
What is the importance of atlanto-occipital joint mobility in intubation?
Crucial for achieving the ‘sniffing position’
Limited mobility can make intubation more challenging.
What is the Cormack and Lehane score used for?
Assessing laryngeal view during intubation
It helps predict the ease of intubation.
What are the implications of limited mobility for intubation?
Limited mobility can indicate a difficult airway and may necessitate alternative approaches or equipment.
Preoperative assessment of neck mobility, including the atlanto-occipital joint, is essential for planning airway management.
What is the Cormack and Lehane Score used for?
It is a grading system for assessing the view of the glottis during laryngoscopy.
The score ranges from Grade I (full view) to Grade IV (no view).
What does a higher Cormack and Lehane Score indicate?
Higher grades indicate a more difficult intubation.
What are the limitations of the Cormack and Lehane Score?
It is subjective and may vary with patient positioning and the skill of the provider.
What is the goal of the sniffing position?
To provide a great view for intubation.
What are indications for awake intubation?
- Anatomical abnormalities (e.g., limited neck mobility)
- History of difficult intubation
- Pathological conditions affecting the airway
- Risk of aspiration
- Respiratory compromise
- Patient cooperation and consent
What is Rapid Sequence Induction (RSI)?
A technique used to secure the airway quickly in high-risk patients.
What are the precautions for Rapid Sequence Induction?
- Requires expertise in airway management
- Equipment for difficult airway management should be available
- Increased risk of hypoxia
What distinguishes Regular Induction from Rapid Sequence Induction?
Regular Induction allows for gradual induction with oxygenation and ventilation, while RSI is for rapid airway securing.
What are the indications for Regular Induction?
- Elective surgeries with confirmed fasting status
- Patients without significant aspiration risk
- Stable airway and respiratory status
What should be monitored during ventilation of an asleep patient?
- Chest rise and fall
- End Tidal CO2 (EtCO2) waveform
- Peak airway pressures
What does the acronym ‘BONES’ stand for in difficult ventilation?
- Beard
- Obese (BMI >26)
- No Teeth
- Elderly (>55 years)
- Snores
What are the general features of anesthesia face masks?
- Various shapes and sizes
- Made from clear, flexible materials
- Cushioned rim for comfort
- Standard connector
- Valves for monitoring carbon dioxide
How is the size of an Oro-Pharyngeal Airway (OPA) determined?
From the corner of the patient’s mouth to the angle of the jaw.
What are the contraindications for using an Oro-Pharyngeal Airway (OPA)?
Conscious patients or those with an intact gag reflex.
What is a Naso-Pharyngeal Airway (NPA) used for?
Useful in both unconscious and conscious patients, especially when oral access is not possible.
What are the contraindications for using a Naso-Pharyngeal Airway (NPA)?
- Severe nasal trauma
- Cribriform plate injury
- Basilar skull fracture
- Coagulopathy
What are the advantages of Supraglottic Airways (SGAs)?
- Easier and quicker to insert
- Reduced risk of airway trauma
- Useful in difficult airway scenarios
What is the maximum recommended cuff pressure for Laryngeal Mask Airways (LMAs)?
Should not exceed 60 cmH2O, with 40 to 60 cmH2O being the recommended range.
What complications can arise from Laryngeal Mask Airways (LMAs)?
- Nerve injury
- Sore throat
- Pharyngeal necrosis
- Nitrous oxide diffusion
What is the technique for one-handed mask ventilation?
Using the left hand to create a C-shape and seal the mask while using the right hand to squeeze the anesthesia bag.
What is the technique for two-handed mask ventilation?
Both hands grip the mask, and the jaw is thrust forward to enhance airway control.
What are the indications for using a Laryngeal Mask Airway (LMA)?
Indicated for general anesthesia in surgeries where endotracheal intubation is not required.
What are the disadvantages of Supraglottic Airways (SGAs)?
- Less protective against aspiration than endotracheal tubes
- Careful sizing is important
What are the complications associated with LMAs?
- Nerve Injury
- Sore Throat and Pharyngeal Necrosis
- Nitrous Oxide Diffusion
Overinflation can cause nerve injury to the lingual, hypoglossal, and recurrent laryngeal nerves. Excessive cuff pressure can damage pharyngeal tissues. Nitrous oxide can increase cuff pressure during anesthesia.
What are the indications for using LMAs?
Indicated for general anesthesia in surgeries where endotracheal intubation is not necessary.
Not suitable for surgeries with a high risk of aspiration or in patients with severe airway obstruction.
What are the advantages of LMAs over endotracheal tubes?
- Easier and quicker to insert
- Less invasive with a lower risk of trauma to the airway
These features make LMAs a preferred choice in certain surgical situations.
What is the design of the LMA Classic?
- Reusable silicone device
- Inflatable cuff
- Suitable for routine surgeries
- Does not have a gastric access port
It is the original Laryngeal Mask Airway design.
Describe the LMA Supreme.
- Single-use device
- Anatomically curved airway tube
- Integrated bite block and gastric access channel
- Higher seal pressure and risk reduction for aspiration
Designed for improved safety and easier insertion due to its preformed curved shape.
What is the purpose of the LMA Fastrach?
- Designed for difficult airway management
- Allows for blind or fiberoptic-guided intubation
- Known as the ‘intubating LMA’ (ILMA)
- Facilitates endotracheal tube placement through the LMA
Suitable for patients with known or suspected difficult airways.
What features distinguish the LMA C-Trach?
- Integrated camera and monitor
- Visualization of the larynx during insertion
- Real-time visual guidance for intubation
- More complex and expensive
Adaptation of the LMA Fastrach.
What is the unique feature of the iGel?
- Non-inflatable cuff
- Creates an anatomical seal around the laryngeal inlet
- Incorporates a gastric channel
- Known for ease of insertion and minimal risk of tissue compression
Made from a thermoplastic elastomer.
What is the design of the Combitube?
- Dual-lumen airway device
- One tube ends blindly (esophageal lumen)
- Other opens at the level of vocal cords (tracheal lumen)
Designed for emergency airway management.
What is the placement technique for the Combitube?
- Inserted blindly into the oropharynx
- Both cuffs are inflated post-insertion
- Ventilation is initially attempted through the esophageal lumen
If inadequate, ventilation switches to the tracheal lumen.
What distinguishes the King Laryngeal Tube?
- Single-lumen airway device
- Ventilation port between two inflatable cuffs
- Designed to sit in the esophagus
It blocks the esophagus and oropharynx.
What is the advantage of the Miller blade?
- Straight blade design
- Directly lifts the epiglottis
- Preferred for infants and small children
Provides more control in difficult airway scenarios.
What is direct vision laryngoscopy?
A technique where vocal cords are directly visualized using a laryngoscope.
Requires alignment of oral, pharyngeal, and laryngeal axes.
What is video laryngoscopy?
Uses a laryngoscope with a camera to visualize the vocal cords on a monitor.
Reduces the need for physical manipulation of the patient’s neck.
What are the parts of an endotracheal tube?
- Connector
- Cuff
- Tube body
- Murphy eye
The connector connects the tube to the breathing circuit.
What are the indications for endotracheal tubes?
- General anesthesia for surgeries
- Mechanical ventilation for respiratory failure
- Emergency airway management
Essential for definitive airway protection.
What are the limitations of endotracheal tubes?
- More invasive than supraglottic airways
- Higher risk of trauma
- Requires skill for safe insertion
Can cause discomfort, necessitating sedation.
What complications can arise from endotracheal tube insertion?
- Injury to teeth, larynx, or trachea
- Risk of laryngospasm or bronchospasm
- Long-term use complications
May lead to vocal cord damage or tracheal stenosis.
What are the risks associated with endotracheal tube insertion?
Injury to teeth, larynx, or trachea; risk of laryngospasm or bronchospasm; long-term use can lead to vocal cord damage or tracheal stenosis.
What is the function of the connector on an endotracheal tube?
Connects the tube to the breathing circuit or ventilation equipment.
What does the pilot balloon indicate?
The status of the cuff (inflated or deflated) and allows for manual adjustment of cuff pressure.
What is the purpose of the cuff on an endotracheal tube?
Seals the space between the tracheal walls and the tube to prevent air leaks and aspiration of gastric contents.
What is the recommended cuff pressure to prevent tracheal injury?
Less than 25 cmH2O.
What is the Murphy eye on an endotracheal tube?
A small hole near the beveled tip that serves as an additional passage for air if the main distal opening becomes blocked.
What is the design feature of an Oral RAE tube?
Curved at the distal end, directed anteriorly towards the patient’s face.
What is the primary purpose of a Nasal RAE tube?
Used for nasal intubations, particularly in surgeries needing access to the mouth or airway.
What distinguishes a Reinforced (Armored/Flexible) tube?
Features spiral wire reinforcement, making it kink-resistant.
What is the main advantage of using a double-lumen endobronchial tube?
Allows for one-lung ventilation, essential in certain thoracic procedures.
Cuffed vs. Uncuffed Tubes: Which type is primarily used in adults?
Cuffed tubes.
What is the primary function of laser-resistant tubes?
Used in surgeries involving laser use in the airway.
What are the characteristics of Low Volume High Pressure (LVHP) cuffs?
Require higher pressure to achieve an adequate seal, are more rigid, and increase the risk of ischemic damage.
What are the advantages of High Volume Low Pressure (HVLP) cuffs?
- Reduced risk of tracheal mucosal damage
- Improved patient comfort
- Lower incidence of post-extubation complications.
What is the purpose of the Eschmann Introducer (Bougie)?
Used in difficult airway situations to guide the endotracheal tube.
What are the key design features of the Cook Exchange Catheter?
- External diameters of 2.7 mm, 3.7 mm, 4.7 mm, and 6.33 mm
- Central lumen for oxygen insufflation or jet ventilation
- Soft, rounded, atraumatic distal tip.
What is a bronchial blocker used for?
Achieving lung isolation during one-lung ventilation.
List the types of bronchial blockers.
- Arndt Endobronchial Blocker
- Cohen Flex-Tip Endobronchial Blocker
- EZ-Blocker
- Univent Tube.
What is a key limitation of bronchial blockers?
High risk of displacement, especially with high-pressure balloons.
What are the indications for using flexible fiberoptic bronchoscopy for intubation?
- Anticipated difficult airway
- Previous difficult intubation.
What is the importance of continuous oxygenation during fiberoptic intubation?
Helps maintain oxygen levels, especially in compromised airways.
What is the function of the steering mechanism in a fiberoptic bronchoscope?
Allows for directional control of the tip during navigation.
What are the indications for using a bronchial blocker?
- Thoracic surgery requiring one-lung ventilation
- Patients with difficult intubation
- Airway protection in unilateral pulmonary bleeding.
What is a potential risk when using the Cook Exchange Catheter?
Risk of barotrauma from excessive pressure during jet ventilation.
What is the primary purpose of a bronchoscope during intubation?
To visualize the airway structures in real-time using a camera and light source
Enables operators to guide the bronchoscope tip towards the vocal cords and through the trachea.
List three indications for awake fiberoptic intubation.
- Anticipated Difficult Airway
- Risk of Aspiration
- Respiratory Compromise
What are absolute contraindications for awake fiberoptic intubation?
- Severe oropharyngeal or nasopharyngeal pathology
- Uncooperative patients
Fill in the blank: Adequate _______ of the airway and light sedation are crucial for patient comfort during awake intubation.
topical anesthesia
What is the first step in the awake fiberoptic intubation process?
Pre-Intubation Preparation
This includes assessing the patient’s airway anatomy and obtaining informed consent.
What is the purpose of nebulized lidocaine in awake fiberoptic intubation?
To anesthetize the airway more thoroughly
True or False: Severe coagulopathy is an absolute contraindication for awake fiberoptic intubation.
False
It is a relative contraindication.
What should be monitored continuously during awake intubation?
Vital signs and oxygen saturation
What is the purpose of a percutaneous cricothyroidotomy?
To establish an airway in emergency situations where intubation is impossible
Identify the landmarks for performing a percutaneous cricothyroidotomy.
Cricothyroid membrane, located between the thyroid and cricoid cartilage
What angle should the cannula be inserted during a cricothyroidotomy?
Caudal angle (45 degrees to the skin)
What are the indications for retrograde intubation?
- Anatomical challenges
- Significant facial trauma
- Limited mouth opening
- Cervical spine immobilization
NOT USED FOR EMERGENCIES AS TAKES TO MUCH TIME
What is a key advantage of the Bullard Laryngoscope?
Enhanced visualization of the glottis with minimal neck movement
Fill in the blank: The Bullard Laryngoscope incorporates _______ technology for clear visualization.
fiberoptic
What is the primary function of a lighted stylet?
To guide the endotracheal tube into the trachea using light transillumination
List two advantages of using a lighted stylet.
- Enhanced visualization
- Minimally invasive
What is a critical consideration when using a lighted stylet?
Risk of tissue damage from excessive pressure
What should be done if awake fiberoptic intubation is unsuccessful?
Have a plan B and C for airway management
What patient condition can make traditional laryngoscopy challenging?
Obesity
What should be done after confirming the placement of an endotracheal tube?
Secure the tube
