Flashcards in ECEs Deck (81)
What are the components of the anesthesia exam?
mouth opening (3 fingers), neck flexion (chin to chest, look up), Mallampati classification, thyromental distance (next extended, bottom of chin to thyroid notch 3-4finger breadths)
How is the thyromental distance taken, and what should it be?
neck extended, distance from bottom of chin to thyroid notch; should be at least 3-4 finger breadths
What are the Mallampati classes?
Class 1: Soft palate, uvula, tonsillar pillars can be seen.
Class 2: As above except tonsillar pillars not seen.
Class 3: Only base of uvula is seen.
Class 4: Only tongue and hard palate can be seen.
What is normal neck ROM?
What are the pros and cons of an LMA?
Pros: easy to insert, bypasses supraglottic structures (eg tongue won't block airway), frees up anesthetist's hands; can deliver some positive pressure ventilation
Cons: still invasive; doesn't have advantages of ET
What are the pros and cons of ET intubation?
Pros: patency of airway; minimal aspiration risk (airway protection); enables mechanical ventilation
Cons: invasive; difficult (skill + tools); risk of misplacement (in esophagus, or R bronchus); risk of damage to cord structures
When do you need mechanical ventilation (& thus ET tube)?
Surgery requires muscle relaxation (eg neurosurgery); surgery involves thoracic cavity; surgery is very long (resp muscles might fatigue)
How do you confirm placement of ET tube?
Gold standard is direct visualization of ETT between vocal cords
Normal end-tidal CO2 confirms (except in cardiac arrest)
auscultation of both lungs + epigastrium
vapour in ETT supportive but not confirmatory.
What identifies placement of tube in R bronchus?
R breath sounds and ø L breath sounds on auscultation. Excess advancement of tube (F: >20cm, M: >22cm)
Walk through the steps of intubation
pt in “sniffing position”
introduce Macintosh blade into R, sweeping tongue to L
advance tip to the space between base of tongue & epiglottis (the vallecula)
keep wrist stiff and don’t leverage blade (eg against teeth)
lift laryngoscope, exposing vocal cords & glottic opening
insert ETT under direct vision through cords
What size ETT should you use?
Size 7.0 or 7.5 ETT for adult female, size 8.0 or 8.5 for adult male
When you insert a supraglottic airway, where would its tip be if adequately placed?
Upper esophageal sphincter
Think of clinical situations in which supraglottic airways may be used instead of an endotracheal tube.
Urgent situations, or as a temporizing measure
Lower extremity orthopedic surgeries when pt want general
For surgical efficiency: eg can go to PACU without anesthetist, with LMA in
Why NOT to use it? COVID!
What are the ASA classes?
1: A normal healthy patient in need of surgery for a localized condition.
2: A patient with mild to moderate systemic disease; examples include controlled hypertension, mild asthma.
3: A patient with severe systemic disease; examples include complicated diabetes, uncontrolled hypertension, stable angina.
4: A patient with life-threatening systemic disease; examples include renal failure or unstable angina.
5: A moribund patient who is not expected to survive 24 hours with or without the operation; examples include a patient with a ruptured abdominal aortic aneurysm in profound hypovolemic shock.
What is malignant hyperthermia?
autosomal dominant variant → changes in Ca++ processing in muscle, in context of inhalational anesthetics or succinylcholine → … → CV collapse, vital organ failure, coma, death
What is pseudocholinesterase deficiency?
Genetic deficiency in pseudocholinesterase; prolongs response to succinylcholine
What are important questions for pre-anesthetic history?
Any cardiac or respiratory disease Hx. Any hepatic or renal disease Hx. Any other disease Hx.
Medications. Hx of adverse drug reactions.
Pt and F Hx with anesthesia.
Specific Qs re: malignant hyperthermia and pseudocholinesterase deficiency.
Soc Hx, incl smoking and EtOH.
If pre-op: Medications and NPO status today.
What are the main anatomical landmarks to visualize on intubation?
Epiglottis, vocal cords, artytenoids
How is the laryngoscopy technique different for curved vs straight blades?
Macintosh (curved) vs Miller (straight): Macintosh blade is inserted into the vallecula anterior to the epiglottis, whereas Miller blade is inserted posterior to the epiglottis and lifts it upwards while depressing the tongue for direct laryngoscopy.
How does video compare to direct laryngoscopy?
Video: Decreases the amount of force needed for laryngoscopy. Allows for glottic visualization when there is limited mouth opening, neck immobility/ injury, or an anterior airway. Is not reliable with airway blood or secretions.
Think of strategies to minimize tooth and lip damage during laryngoscopy.
Strategies to limit tooth damage: keep arm straight, lift up, check in, position self well … consier using video
What are the absolute contraindications to central anesthesia (or LP)?
coagulopathy, sepsis (systemic or at site of injection), increased intracranial pressure (ICP), shock
What are the relative contraindications to central anesthesia (or LP)?
evolving neurological deficit, obstructive cardiac lesion (e.g. aortic stenosis), spinal hardware
What are the structures that spinal needle passes through while being inserted?
Layers: skin, superficial fat & fascia, supraspinous ligament, interspinous ligament, ligamentum flavum, into epidural space; if spinal, on through the dura
How is a spinal anesthetic different from an epidural?
Spinal goes intrathecally and acts on the spinal cord. Epidural goes in epidural space and acts on the nerve roots.
What are signs of local anesthetic toxicity?
tinnitus, perioral numbness, metallic taste in mouth, dizziness - might experience if catheter is in vein
What are the contraindications for epidural anesthesia?
Same as for spinal
What is a sign of misplacement of epidural intrathecally?
sensory/motor block after only small amount of local anesthetic
What is the pathophysiology of post dural puncture headache?
reduced CSF pressure due to loss of CSF in the epidural space through the dural puncture site