Case presentation & airway obstruction

1. Case presentation & airway obstruction Ri 楊朝能 Ri 梁富珍 指導者：CR 黃信豪\VS 鄭雅蓉

2. Present illness • 56 y/o male patient without any other systemic disease • C.C：intermittent high fever for 2 weeks • He suffered from dry cough with intermittent high fever for 2 weeks • He has been to 和平 Hospital for help and prescribed with some kind of antibiotics but symptoms persisted without improvement after taking medications • So, he went to our ER for help.

3. Present illness • At our ER, decreased RLL breathing sound and fever up to 39℃ were noted. • Initial white count 23240/μL • D/C : Seg 88.1% • CxR

4. Hospitalization • Tentative diagnosis ：pneumonia • Admitted to 6A • Treated with Unasyn and mucolytic agents • Chest CT

5. FVC 2.25L (72.1%) FEV1 1.79L (70.2%) Mild restrictive ventilatory defect Pulmonary function test

6. Original surgical method

7. Intubation with Wu scope above the level of obstruction Fiberoptic bronchoscope as a guidewire to Lt main bronchus Bingo!! Check Intubation with double lumen

8. Anesthesia 0 1 2 3 4 5 6 7 8 9hr Fentanyl (epidural) Propofol Esmeron Epidural 5ml/hr infusion Xylocaine KCl IVD Midazolam N2O/O2/air Sevo

9. OP finding and method RUL sleeve lobectomy plus LN dissection

10. Malignant airway obstruction

11. Content 1.Cause and pathophysiology 2.Assessment and diagnosis Clinical manifestation,physical examination, other diagnostic tool 3.Anesthetic Management -Medication for premedication,induction,maintenance -Selection of intubation's technique -Lung isolation for pulmonary resection,right side -Intraoperative care, potsoperative analgesia

12. Cause and pathophysiology (from The Journal of Emergency Medicine,16(1), pp83-92, 1998)

13. Assessment and diagnosis(1) History : risk factor-smoking!!(COPD or CAD) Clinical manifestation: 1.Depend on : severity, location, external compression or infiltration of tumor into the lumen. 2.Usually worsen in the supine position 3.Location : (1)Airway above the vocal cord: Snoring, Hoarseness, dysphagia… (2)Trachea or carina: dyspnea, stridor, drooling, cough, and wheeze… (3) Distal airway: obstructive pneumonitis…

14. Assessment and diagnosis(2) 4.Less frequent manifestation : (1)Compression of the tracheobronchial tree, heart, and major vessel : superior mediastinal syndrome (cough, stridor, dyspnea, orthopnea) (2) Superior vena cava syndrome : venous engorgement, head or neck edema. (3) Great vessel compression : altered mental status

15. Assessment and diagnosis(3) Physical examination : 1.Inspection : perioral or acrocyanosis;diaphoresis,use accessory muscle for breathing;asymmetric chest wall movement (main bronchus)… 2.Palpation : decreased fremitus over the affected side. 3.Percussion : increased dullness

16. Assessment and diagnosis(4) 4.Auscultation : Inspiratory stridor  obstruction within the upper airway, glottis, subglottis, or trachea. Expiratory wheezing  bronchoconstriction or obstruction of the trachea, subglottis, glottis. Attenuation of breath sounds  post-stenotic atelectasis or tumor- related pneumothorax. Crackles over the corresponding  poststenotic pneumonia (productive cough, fever)

17. Assessment and diagnosis(4) Diagnostic tool : 1.plain chest X-ray : deviation of the trachea, narrowing of the airways, consolidation , atelectasis… 2.Pulse oximetry : degree of hypoxemia 3.Spirometry(flow-volume loop) : • confirm the location of the obstruction and aid the clinician in the evaluating it’s severity(insensitive) • narrows the tracheal lumen to less than 8 mm in diameter (>80%) will be detected.

18. Spirometry:flow-volume loop Variable extrathoracic obstruction Normal Variable intrathoracic obstruction Fixed large airway obstruction (Clinical anesthesiology 2nd edition.p.468)

19. Assessment and diagnosis(5) 4.CT : for localizing the lesion;inability to image the airway longitudinally. 5.MRI : children and infant 6.Fiberoptic bronchoscope : important dignostic tool (1)direct visualization of the obstructing tumor (2)rapidly identifythe possible cause of airway obstruction (3)initiate the appropriate measures for securing or reestablishing the patency of the airway in a timely and effective manner (4)biopsy

20. Management- premedication Proper positioning is critical to avoid injuries(severe obstruction..) and to facilitate surgical exposure Premedication : decrease secretion and optimize the laryngoscopic view of the airway -Atropine and Glycoopyrolate. Induction: Spontaneous ventilation is maintained throughout induction  keep in mind : The use of neuromuscular blocking drugs may eliminate theonly muscular tone that is keeping the airway patent. ( The Journal of Emergency Medicine,16(1), pp83-92, 1998)

21. Management-induction Intravenous induction : a more rapid and smoother induction,as well as less airway irritation; however, if inductionis too rapid, the airway may be lost. Sevoflurane:a low blood gas solubility coefficient (0.68), a pleasant smell,and less airway irritation Loss of airway control :using both types of induction Short actingnarcotics and muscle relaxants- if awake intubation is not possible.

22. Management-maintenance low dose ketamine:increased secretion and hyperreactive airway-might not be optimal principle : little respiratory depression and short acting drug After secure airway established - maintenance of anesthesia In the stable patient, the combination of a proper inhalational anesthetic agent and a short-actingintravenous anesthetic agent such as propofol, along with midazolam,fentanyl, and vecuronium- effective and safe anesthesia,amnesia, pain control, and muscle relaxation. (Am J Respir Crit Care Med Vol 169.pp1278-1297,2004)

23. Management-Selection of intubation's technique(1) According to the level of airway obstruction and placement of the EET beyond the level of obstruction 1.Lesions in the upper airway (1)tongue,nasopharynx,larynx,epiglottis and vocal cords (2)surgical airway(tracheostomy or cricothyrotomy) under local anesthesia with the patient awake and breathing spontaneously. (3)awake fiberoptic intubation with smaller size(i.e., 5.5, 6.0, 6.5) ----patient in a sitting position (The Journal of Emergency Medicine,16(1), pp83-92, 1998)

24. Management-Selection of intubation's technique(2) (4) gentle intubation to avoid massive bleeding(for highly vascularized tumor) (5) LMA:most probably not pass the obstruction and will not solve the problem. (6)All alternatives for the management for a difficult airway and sufficient personnel(including tracheostomy kit) should be ready.

25. Management-Selection of intubation's technique(3) 2.Lesions or compression at the level of the trachea (1)small-sized tubes or nasogastric tubes may be required to pass the level of obstruction below the vocal cords. (2)Jet ventilation through a nasogastric tube may be a valuable alternative,if available.

26. Management-Selection of intubation's technique(4) 3.Lesions at or below the level of the mainstem bronchus (1)placement of a regular-sized endotracheal tube and ventilation of at leastone lung. (2)separation of the lungs -deep intubation with a regular endotracheal tube or -placement of a bronchial blocker or -a Univent-tube or -a double-lumen endobronchial tube (3)Isolation of one lung - in the case of tumor-related bleeding or secondary infection from one side of the lungs.

27. Management-Lung isolation for pulmonary resection , right side(1) 1.The first choice is a leftdouble lumen tube 2.There is a widemargin of safety in positioning left DLTs. 3.With blind initialplacement the incidence of malpositioning is high(30%) but is correctablein virtually all cases by fiberoptic adjustment. 4. A partial resection can proceed to a pneumonectomy, if required,without loss of lung isolation. 5. There is continuous access tothe non-ventilated lung for suctioning, fiberoptic monitoringof position, and CPAP. (CAN J Anesthesia, 48(6), pp R1-R10, 2001)

28. Management-Lung isolation for pulmonary resection , right side(2) 6. Possible alternatives are: (1) single lumen endobronchial tube.A standard 7.5 mm ID or smaller ET tube can be advanced overa fiberoptic bronchoscope (FOB) into the left mainstem bronchus; (2) Univent tube or other bronchial blocker. This is one ofthe least favorable clinical situations in which to use a blockersince the margin of safety for optimal positioning is smalland blockers tend to move intra-operatively especially duringsurgical lung manipulation

29. Management-Intraoperative care(1) 1.Ventilation : (1)can be achieved via a closed system (2)Alert for the redevelopment of airway obstruction after the procedure, which is typically due to the mobilization ofsecretions from a previously obstructed bronchus; however, sloughedtissue, blood clot, or a migrated stent may also be the cause. (Am J Respir Crit Care Med Vol 169.pp1278-1297,2004)

30. Management-Intraoperative care(2) 2. Airway fires : (1)Fires can result from either the use of a flammable anesthetic,or, more commonly, from the use of high concentrations of oxygenin the presence of lasers or electrocautery. (2)In addition, endotrachealtubes and stents can ignite with the use of laser or electrocautery. The FIO2 should be less than 0.4 whenever these techniquesare used.

31. Management-Intraoperative care(3) 3. Intravenous fluids should generally be restricted in patient undergoing pulmonary resection.(basic maintain requirement and replacement of blood loss) Lower lung syndrome:excessive fluid administration in the lateral decubitus position(gravity dependent transudation of fluid into the dependent lung) intrapulmonary shunting,hypoxemia.(especially one lung ventilation)

32. Management-Intraoperative care(2) 4.Return of spontaneous ventilation and early extubation at the end of the procedure are disirable? 5.Patient should be positioned with the neck flexed immediately postoperatively after the operation to minimize tension on the suture line.

33. Postoperative analgesia 1.Balance between comfortable and respiratory depression.postoperative complication. 2.(1) Parenteral narcotics(small IV superior to large IM) (2) A long-acting agent(ex:0.5% bupivacaine) injected two levels above and below the thoracotomy incision) (3) Epidural injections of lipophilic opioids such as fentanyl may be more effective via a thoracic catheter than a lumbar cartheter (fentanyl:less likely to cause delayed ,respiratory depression)

34. Summary(1) • Airway obstruction S/S: increasing shortness of breath, recurrent chest infection, hemoptysis, and an inability to lie flat. • Induction: avoid respiratory depressing sedation, mucsle relaxants or narcotics(short-acting) • Selection of intubation’s technique: According to the level of airway obstruction (placement of endotracheal tube beyond the level of obstruction). • Be aware of the patient’s position

35. Summary(2) • Alert for the redevelopment of airway obstruction afterthe procedure (secretions from a previously obstructed bronchus, sloughed tissue, blood clot, or a migrated stent) • Airway fires • Lower lung syndrome

36. Reference • Armin E, David F, Heinrich D, et al.Central airway obstruction. American journal of respiratory critical care medicine 2004: 169: 1278-1297. • Peter S.Lung isolation in thoracic anesthesia, state of the art. Canada journal of anesthesia 2001: 48(6): R1-R10. 3. Karen C, Joseph V, Olivier C.Management airway obstruction:recognition and management. The journal of emergency medicine 1998: 16(1): 83-92.

37. Thanks for your attention!