12-16-20_Lung_Anatomy__biochemistry__transplant_-_Dr._Reformato.pdf

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1. Lung Anatomy and Biochemistry & Lung Transplant Vincent Reformato, MD 12/16/2020
2. Lung Anatomy
3. Respiratory System
4. Which of the following structures would be effectively anesthetized by injection of lidocaine into the anterior tonsillar pillars bilaterally? A. Soft palate and oropharynx B. Anterior 2/3 of tongue C. Hypopharynx D. Vocal Cords
5. A. Soft palate and orophaynx  Innervation:  Anterior 2/3 of tongue: V3 (Trigeminal, mandibular branch)  Posterior 1/3 of tonue: IX (glossopharyngeal)  Soft Palate: IX  Oropharynx: IX  Hypopharynx (below epiglottis): Internal Branch of Superior Laryngeal Nerve (X)  Vocal Cords: internal branch of SLN and RLN (X)  Larynx (below vocal cords, above trachea): RLN (X)  Trachea: RLN (X)
6. Pharynx  Subdivisions  Nasopharynx  Ends at soft palate  Oropharynx  Extends to epiglottis  Hypopharynx  From epiglottis to level of cricoid cartilage  Innervation  Sensory: glossopharyngeal (IX)  Motor: Pharyngeal branch of Vagus (X)  Except sylopharyngeus – glossopharyngeal (IX)
7. Which of the following structures would be effectively anesthetized by injection of lidocaine inferior to the greater cornu of the hyoid bone? A. Recurrent Laryngeal Nerve B. Glossopharyngeal Nerve C. Superior laryngeal nerve, internal branch D. Superior laryngeal nerve, external branch
8. C. Superior Laryngeal Nerve, internal branch  The superior laryngeal nerve branches into internal and external components  Internal branch provides sensory input to the larynx above the level of the vocal cords and is the target for the superior laryngeal nerve block.  External branch provides motor innervation to the cricothyroid muscle.  Blockade is achieved by instilling local anesthetic at the level of the thyrohyoid membrane at the inferior aspect of the greater cornu of hyoid bone  The Recurrent laryngeal nerve provides sensory innervation to the larynx below the level of the vocal cords and motor innervation to all intrinsic muscles of the larynx except for the cricothyroid  The Glossopharyngeal neve supplies taste and i8nnervation to the posterior 1/3 of the tongue, motor innervation to the pharynx and sensory innervation to the pharynx (with vagal contribution)
9. Larynx  Innervation  Sensory- Internal branch of superior laryngeal  Motor- Recurrent laryngeal  Exception! Cricothyroid: external branch of superior laryngeal
10. Laryngeal Cartilages  Thyroid  Cricoid  Epiglottis  Arytenoids  Cornicuate  Cuneiform
11. Intrinsic Laryngeal Muscles  Intrinsic  Cricothyroid  Lenthen and tense vocal cords  Posterior cricoarytenoid  ABduct VC  Lateral cricoarytenoid  Increase medial compression  Transverse arytenoid  ADduct VC  Oblique arytenoid  Constricts distance between arytenoids  Thyroarytenoid  narrows the laryngeal inlet, shortens the vocal folds, and lowers voice pitch
12. Extrinsic Laryngeal Muscles  Sternothyroid  Omohyoid  Sternohyoid  Inferior constrictors  Thyrohyoid  Digastric  Stylohyoid  Mylohyoid  Geniohyoid  Hyoglossus  Genioglossus
13. Laryngeal Blood Supply  Upper Half  Superior Laryngeal Artery  Branch of Superior Thyroid Artery <- External Carotid  Lower Half  Inferior Laryngeal Artery  Branch of Inferior Thyroid Artery <- Thyrocervical Trunk <-Subclavian
14. Vocal Cord Paralysis
15. In a follow-up after surgery and anesthesia, a patient notes significant hoarseness. In order to evaluate the patient's vocal cords a diagnostic fiberoptic examination is performed. If unilateral injury to the recurrent laryngeal nerve has ocurred, what will be the position of the affected vocal cord? A. fixed in ADducted position B. fixed in ABducted position C. fixed in paramedian position D. able to ADduct, but weak ABduction E. able to ABduct, but weak ADDuction
16. C. Fixed in paramedian position  A fixed paramedian position results from unopposed action of the cricothyroid muscle (innervated by superior laryngeal nerve, external branch) which increases length and tension of the vocal cords.
17. Pediatric vs. Adult Airway  Large tongue  Occiput  Larynx and trachea conical (uncuffed tubes)  Narrowest portion at cricoid  Larynx higher (C4 in peds, C6 in adults)  Vocal cords directed upward in child (horizontal in adults)
18. Muscles of Respiration
19. Lung Biochemistry
20. Which of the following statements is/are true about the mechanism of action of exogenous glucocorticoids? A. They directly bind to glucocorticoid receptors toe exert their action. B. They inhibit molecules such as cytokines, chemokines, and arachidonic acid metabolites. C. They upregulate anti-inflammatory mediators. D. All of the above.
21. D. All of the above Endogenous glucocorticoids are synthesized in the adrenal cortex. Exogenous glucocorticoids (I.e. methylprednisolone, prednisone, fluticasone, and budesonide) are commonly used steroid agents for inflammatory diseases such as asthma. Their mechanism of action is exerted by binding of endogenous glucocorticoid receptors, which leads to inhibition of inflammatory molecules such as cytokines, chemokines, and arachidonic acid metabolites. They also upregulate anti- inflammatory mediators.
22. β-Agonists  Ex. Albuterol, metaproterenol, terbutaline  At bronchial smooth muscle, +cAPM-> -Ca2+ -> muscle relaxation  Β2 selectivity avoids cardiac excitation
23. Anticholinergics  Ex. Ipratropium  Quarternary ammonium compounds (do not enter blood stream when inhaled)  Block cGMP production -> less Ach -> low cholinergic tone, less bronchoconstriction
24. Steroids  Inhaled (Fluticasone, Budesonide)  Systemic (glucocorticoids)  Increases production of inflammatory mediators, leading to bronchodilation
25. Leukotriene Modifiers  Ex Montelukast (Singulair)  Blocks leukotriene D4 in lungs -> no smooth muscle constriction
26. Mast Cell Stabilizers  I.e Cromolyn  Blocks histamine release and cytokines for exercise and allergen induced asthma  Possible role in Calcium inhibition
27. Immunoglobulin E Blockers  Monoclonal antibodies (omalizumab [Xolair])  Prevent crosslinking of antibodies and downstream effects  Block release of histamine, leukotrienes,tryptase, inflammatory cytokines,
28. Which of the following is TRUEregarding anticholinergic bronchodilators?  A. They act to block nicotinic receptors.  B. they block the formation of cyclic GMP  C. They are muscarinic agonists  D. B and C.
29. B. They block the formation of cGMP Anticholinergics, such as ipratropium, block the formation of cGMP, which promotes bronchodilation. They act as a muscarinic antagonist and have no action on nicotinic receptors.
30. Lung Transplantation INDICATIONS 1. COPD 2. Interstitial lung disease 3. Cystic Fibrosis 4. Primary pulmonary hypertension
31. Contraindications ABSOLUTE  Untreatable dysfunction of another major organ (Heart, liver, kidney)  Malignancy within 2 years  Psychiatric disorder or noncopliant behavior  Substance addiction  Chronic active Hep B or C, or HIV  Significant chest or spinal deformity  Noncurable chronic extrapulmonary infection RELATIVE  Age >65  Unstable condition (shock, ECMO)  Limited functional status  Severe obesity  Severe/symptomatic osteoporosis  Colonization with highly resistant or virulent bacteria, fungi, or mycobacteria
32. Lung Transplant Variations  Single Lung  Bilateral Sequential (Double) Lung  Combined Heart-Lung  Living-related Lobar Transplant
33. Anesthetic Technique  Double Lumen Ett  Invasive Monitors  A-Line, PA catheter, TEE  +/- CPB  +/- ECMO  Respiratory support  Inhaled Agents for Pulmonary Hypertension  Inhaled Nitric Oxide  Inhaled Epoprostenol
34. Double Lumen ETTs  Lets Examine!
35. Specific Considerations COPD  Hypotension on induction (positive pressure ventilation) CYSTIC FIBROSIS  Difficult ventilation  Slower Inspiratory phase and high pressures  Thick secretions PULMONARY HYPERTENSION  Hemodynamic collapse on induction  Right heart dysfunction PULMONARY FIBROSIS  Poor tolerance of OLV