Case 45 - functional endoscopic sinus surgery

Question 1

what are the complications assoc with functional endoscopic sinus surgery (FESS)?

Answer 1

divided into three groups: orbital, intracranial, and nasal

complications increase with uncontrolled or excessive intraop bleeding –> impairs surgical field visualization of important anatomic structures

orbital

• hemorrhage
• abscess
• blindness 2/2 damage to optic n

intracranial

• csf leak
• meningitis or brain abscess
• intracranial hemorrhage

Nasal

• adhesions
• anosmia
• injury to lacrimal duct

Question 2

what are the anesthetic goals for FESS?

Answer 2

Major goal is facilitate a ‘bloodless’ surgical field

Anes considerations

• secure airway and prevent aspiratoin
• facilitate bloodless surgical field –> induced hypotension
• outpatient ambulatory procedure recovery profile
  
  • pain control
  • PONV
  • smooth and rapid emergence (avoid coughing or bucking)

Question 3

What are ways to provide a bloodless field?

Answer 3

Main goal of FESS: provide bloodless field to improve surgical visualization

Ways to provide bloodless field:

1) induced hypotension
2) d/c pre-op anticoagulants
3) spray cocaine or epi into nose prior to scope insertion for vasoconstriction

Question 4

Patient comes to hospital for FESS. He has CAD, and is on antiplatelet therapy. He also has compensated CHF. What are your concerns, what info should be obtained in preop assessment?

Answer 4

Main goal of FESS: provide bloodless field to improve surgical visualization

Induced Hypotension Concern

• CAD, CHF, valvular disease pts may not tolerate this
• end-organ damage
• assess cardiac reserve, exercise capacity, additional testing as needed

d/c anticoagulant concern

• recent cardiac stent placed? sx must be delayed
• recently saw cardiologist?

vasoconstrictor concern

• patient have significant CAD, valvular pathology, arrhythmias?
• vasoconstrictor induces HTN and tachy

Question 5

What is Samter’s triad? Anes implications?

Answer 5

FESS patients may have Samter’s triad.

Samter’s triad

• reactive airway disease, nasal polyps, ASA sensitivity
• mech –> overproduction of leukotrienes –> can lead to bronchospasm, urticaria, or anaphylaxis
• asa blocks prostaglandins and shifts cascade toward production of leukotriene

Anes implications

1) reactive airway disease

• preop use of inhalers (albuterol, ipratropium), antileukotrienes (motelukast), corticosteroids
• avoid beta blockers for induced hypotension (increase bronchospasm risk)

2) polyps

• usually on steroids
• give preop daily dose, or intraop IV dose to avoid s/sx of adrenal gland insuffiency

Question 6

Explain the concept of controlled or deliberate hypotensive anesthetic technique

Answer 6

Intraop bleeding factors

• vascularity of nasal and sinus mucosa
• intensity of blood flow to surgical site
  
  • influenced by MAP and CVP

MAP

• MAP = SVR x CO
• induced hypotension should not be based on a predetermined value/percentage from baseline, but determined of desired effect = ‘bloodless field’
• balance hypotension with tissue oxygenation & cerebral/coronary blood flow
• *reducing CO shows to be more effective in improving surgical conditions of FESS compared to reducing SVR*

Question 7

What pharmacologic agents can you use to reduce MAP for FESS surgery?

Answer 7

SVR

• reduce with vasodilators (nitroglycerin, prusside, hydralazine, inhaled anes)
• require lower MAP pressure to see desired effect

CO

• reduction more effective in providing bloodless field than reducing SVR
• Factors - preload, afterload, contractility, HR
• Beta blockers –> achieved optical surgical conditions at a higher MAP than vasodilators
• BB –> reduce HR and contractility

Question 8

Explain risks of induced hypotension?

Answer 8

BB reduces CO and is more effective in providing ‘bloodless field’

• Starting BB during perioperative patients who are not taking BB at home –> increased risk of mobidity and mortaility
• reactive airway disease exacerbated with BB
• induced hypotesion for optimal surgical conditions vs. inadequate tissue perfusion leading to tissue hypoxia
  
  • patients may have CAD, carotid stenosis, AS. Will not tolerate hypotension

implementing induced hypotension needs to be tailored and individualized to each person’s needs and limitations

Question 9

Aside from induced hypotension, what else can be done to facilitate a bloodless field?

Answer 9

Goal - minimize intraop bleeding and create bloodless field (reduces surgical risk, time, improves surgical visibility)

1) preop medications

• correct coagulopathies
• consult cards if on anti-PLT therapy
• sx to inject vasoconstrictor and LA into nose (oxymetazoline, phenylephrine, cocaine, epinephrine)
  
  • use cautiousy/avoid in CAD, valvular pathology, cerebrovascular disease

2) position

• head up, reverse t-berg –> pools blood to lower extremity
  
  • consider BP taken at level of heart overestimates BP at brain
  • consider risk of air embolism since head at higher level than heart

3) Anes technique

• TIVA with propofol and remifentail infusion provide superior visualization in surgical field and significant decrease in intraop blood loss compared to inhaled anes.
  
  • reducing CO is better then reducing SVR for reduction in blood loss
  • propofol and remi casue decrease contractility and decrease HR
  • inhaled anes cause decrease SVR (vasodilation)

4) ventilation

• hypocapnia/hyperventilation is favorable
• hypercapnia = tachycardia and vasodilation
• reduce PEEP and airway pressure (can increase CVP and cause pooling of blood in head = increase bleeding)

Question 10

What are the benefits of TIVA compared to inhaled anes for FESS?

Answer 10

Goal is to minimze bleeding:

TIVA

• prop + remi -> Reduce CO (better to reduce than SVR for bloodless field)
  
  • remi - reduces HR due to parasympathetic effect
  • prop - reduces cardiac contracility
• easy titratable
• antiemetic (n/v/retching increases CVP)
• smooth emergence (bucking increase CVP and increase risk of bleeding)

Inhaled Anes

• decrease SVR and therefore MAP.
• providing bloodless field through reducing SVR is inferior to reducing CO

Question 11

What your choices and considerations for pain management following FESS surgery?

Answer 11

• multimodal approach: nonopioid and opioid
  
  • avoid NSAID due to ASA sensitivity (increases luekotrienes = bronchospasm and anaphylaxis)
  • avoid NSAID due to bleeding risk (impair PLT aggregration)
• IV opioids
• regional anesthesia
  
  • V2 - maxillary division of trigeminal nerve supplies innervation to nasal cavity, maxillary sinus, soft and hard palate.
  • two main branches of V2: infraorbital nerve and sphenopalatine ganglion
  • block these nerves provides anesthesia to surgical site

Question 12

what are post-op complications of FESS

Answer 12

• airway obstruction - swelling, bleeding, retained foreign bodies, bronchospasm from Samter’s triad
• bleeding
• PONV
  
  • tx to avoid retching (increase bleeding 2/2 increase CVP)