Thyroid Disease And Surgery

Question 0

How many Parathyroid glands are there and what size are they?

Answer 0

4 glands

4 mm x 6 mm

Question 1

How much does the thyroid gland weigh?

Answer 1

30 gm

Question 2

What nerve anatomy is of major concern when performing thyroid surgery?

Answer 2

Recurrent laryngeal nerves

Question 3

What cranial nerve does the recurrent laryngeal nerve originate from?

Answer 3

CN X

Question 4

The recurrent laryngeal nerves serve all the intrinsic laryngeal muscles except which ?

Answer 4

Cricothyroid muscle

Question 5

In regards to thyroid disease what is a possible plan for induction initial airway management

Answer 5

1) awake vs Sedated vs asleep FFOB intubation? ( Most likely awake if the airway is suspected to be a difficult airway) 2) Which route will it be nasal or oral? 3) What IV induction agent & muscle Relaxant will you use? (Most Likely propofol and succinylcholine–For example if a sternotomy has to be done) 4) Make sure the ETT extends beyond on the lesion, Confirm with FFOB

Question 6

During the maintenance of the case what a possible airway risks?

Answer 6

1) Compression of the trachea by hematoma or pressure via a Goiter 2) Damage to the recurrent laryngeal nerves (no vocal cord abduction)

Question 7

What other risk associated with thyroid removal

Answer 7

Accidental removal of the parathyroid glands Signs of hypocalcemia can manifest as early as 1-3 hours after surgery but typically do not appear until 24 to 72 hours. Symptoms: Inspiratory strider progressing to laryngospasm due to the fact that the laryngeal muscles are very sensitive Hypocalcemia

Question 8

what should you consider when planning emergence and ending airway management for thyroid surgery

Answer 8

1) Should the patient remained intubated 2) should we do Deeb extubation (want to minimize coughing maybe use lidocaine) 3) are there airway risk associated with surgery 4) where there any potential airway problems (Does the patient need to be in ICU) 5) where should a patient go after surgery

Question 9

What muscle is the only abductor for the vocal cords and is innervated by the recurrent laryngeal nerve

Answer 9

PCA (posterior cricoarytenoid)

Question 10

In regards to the RLN, what can happen from retraction, clamping, or electrocautery?

Answer 10

Injury

Question 11

What does it mean when there is interruption of the RLN

Answer 11

The nerve has been severed by scalpel or electrical

Question 12

Pathophysiology of unilateral RLN injury

Answer 12

Acute: affected vocal cord will move to the Median position, Opposed by the normal Vocal cord Long term: effected vocal cord may force the normal vocal cord away from the midline

Question 13

Pathophysiology of bilateral RLN Injury

Answer 13

Acute: upper airway obstruction (Usually occurs in recovery room 5 - 15 minutes after surgery) ( Could be caused by edema or abduction of the cords— as related to all nerves firing due to the injury to RLN). Assist with FFOB Via nasal passage Long-term: resolution of edema

Question 14

Pathophysiology related to interruption of RLN

Answer 14

Overall affect is paramedian vocal cord position which puts the patient at risk for aspiration and dyspnea on exertion

Question 15

List the differential diagnosis for stridor following thyroid or parathyroid surgery

Answer 15

1) Edema-supraglottic/glottic (Immediately following extubation) 2) recurrent laryngeal nerve injury (5-15 minutes Post op) 3) hypocalcemia (4 to 6 hours Post op)