Airway Management: An Introduction and Overview & Massive Hemoptysis Division of Critical Care Medicine University of Alberta Airway Management Outline Overview Normal airway Difficult intubation Structured approach to airway management Causes of failed intubation Overview of the Airway 600 patients die per year from complications related to airway management 3 mechanisms of injury: 1. 2. 3. Esophageal intubation Failure to ventilate Difficult Intubation 98% of Difficult Intubations may be anticipated by performing a thorough evaluation of the airway in advance Indications for Intubation Ventilatory Support Decreased GCS Protection of Airway Ensuring Airway patency Anesthesia and surgery Suctioning and Pulmonary Toilet Hypoxic and Hypercarbic respiratory Failure Pulmonary lavage Endotracheal Intubation Depends Upon Manipulation of: Cervical spine Atlanto-occipital Joint Mandible Oral soft tissues Neck hyoid bone Additionally: Dentition Pathology - Acquired and Congenital The Normal Airway History of one or more easy intubations w/o sequelae Normal appearing face with regular features Normal clear voice Absence of scars, burns, swelling, infections, tumour, or hematoma No history of radiation of the head or neck Ability to lie supine asymptomatically; no history of snoring or sleep apnea The Normal Airway Patent nares Ability to open mouth widely with TMJ rotation and subluxation (3 – 4 cm or two finger breaths) Mallampati Class I Patient sitting straight up, opening mouth as wide as possible, with protruding tongue; the uvula, posterior pharyngeal wall, entire tonsillar pillars, and fauces can be seen At least 6 cm (3 finger breaths) from tip of mandible to thyroid notch with neck extension At least 9 cm from symphysis of mandible to mandible angle The Normal Airway Slender supple neck w/o masses; full range of neck motion Larynx moveable with swallowing and manually moveable laterally (about 1.5 cm each side) Slender to moderate body build Ability to extend atlanto-occipital joint (normal extension is 35°) Risk Factors For Difficult Intubation El-Canouri et al. - prospective study of 10, 507 patients demonstrating difficult intubation with objective airway risk criteria Mouth opening < 4 cm Thyromental distance < 6 cm Mallampati grade 3 or greater Neck movement < 80% Inability to advance mandible (prognathism) Body weight > 110 kg Positive history of difficult intubation Signs Indicative of a Difficult Intubation Trauma, deformity: burns, radiation therapy, infection, swelling, hematoma of face, mouth, larynx, neck Stridor or air hunger Intolerance in the supine position Hoarseness or abnormal voice Mandibular abnormality Decreased mobility or inability to open the mouth at least 3 finger breaths Micrognathia, receding chin Treacher Collins, Peirre Robin, other syndromes Less than 6 cm (3 finger breaths) from tip of the mandible to thyroid notch with neck in full extension < 9 cm from the angle of the jaw to symphysis Increased anterior or posterior mandibular length Signs Indicative of a Difficult Intubation Laryngeal Abnormalities Fixation of larynx to other structures of neck, hyoid, or floor of mouth. Macroglossia Deep, narrow, high arched oropharynx Protruding teeth Mallampati Class 3 and 4 Signs Indicative of a Difficult Intubation Neck Abnormalities Thoracoabdominal abnormalities Short and thick Decreased range of motion (arthritis, spondylitis, disk disease) Fracture (subluxation) Trauma Kyphoscoliosis Prominent chest or large breasts Morbid obesity Term or near term pregnancy Age 50 – 59 Male gender Difficult Intubation - History Previous Intubations Dental problems (bridges, caps, dentures, loose teeth) Respiratory Disease (sleep apnea, smoking, sputum, wheeze) Arthritis (TMJ disease, ankylosing spondylitis, rheumatoid arthritis) Clotting abnormalities (before nasal intubation) Congenital abnormalities Type I DM NPO status Difficult Intubation - Diabetes Mellitus Difficult intubation 10 x higher in long term diabetics Limited joint mobility in 30 – 40 % Prayer sign Unable to straighten the interpharyngeal joints of the fourth and fifth fingers Palm Print 100% sensitive of difficult airway Difficult Intubation - Physical Exam General: LOC, facies and body habitus, presence or absence of cyanosis, posture, pregnancy Facies: Abnormal facial features Nose: Pierre Robin Treacher Collins Klippel – Feil Apert’s syndrome Fetal Alcohol syndrome Acromegaly For nasal intubation Patency Pierre Robin Treacher Collins Difficult Intubation - Physical Exam TMJ Joint – articulation and movement between the mandible and cranium Diseases: Rheumatoid arthritis Ankylosing spondylitis Psoriatic arthritis Degenerative join disease Movements: rotational and advancement of condylar head Normal opening of mouth 5 – 6 cm Difficult Intubation - Physical Exam Oral Cavity Foreign bodies Teeth: Long protruding teeth can restrict access Dental damage 25% of all anesthesia litigations Loose teeth can aspirate Edentulous state Rarely associated with difficulty visualizing airway Tongue: Size and mobility Mallampati Classification Class I: soft palate, tonsillar fauces, tonsillar pillars, and uvuala visualized Class II: soft palate, tonsillar fauces, and uvula visualized Class III: soft palate and base of uvula visualized Class IV: soft palate not visualized Class III and IV Difficult to Intubate Mallampati Classification Structured Approach to Airway Management MOUTHS Component Description Assessment Activities Mandible Length and subluxation Measure hyomental distance and anterior displacement of mandible Opening Base, symmetry, range Assess and measure mouth opening in centimetres Uvula Visibility Assess pharyngeal structures and classify Teeth Dentition Assess for presence of loose teeth and dental appliances Head Flexion, extension, rotation of head/neck and cervical spine Assess all ranges and movement Silhouette Upper body abnormalities, both anterior and posterior Identify potential impact on control of airway of large breasts, buffalo hump, kyphosis, etc. Bag/Valve/Mask Ventilation Always need to anticipate difficult mask ventilation Langeron et al. 1502 patients reported a 5% incidence of difficult mask ventilation 5 independent risk factors of difficult mask ventilation: Two of these predictors of DMV Beard BMI > 26 Edentulous Age > 55 years of age History of snoring (obstruction) Sensitivity and specificity > 70% DMV Difficult Intubation in 30% of cases Intubation Technique Preparation: Equipment Check 100% oxygen at high flows (> 10 Lpm) during bask/mask ventilation Suction apparatus Intubation tray Two laryngoscopic handles and blades Airways ET tubes Needles and syringes Stylet KY Jelly Suction Yankauer Magill Forceps LMA’s Pre - oxygenation Traditional: Rapid 3 minutes of tidal volume breathing at 5 ml/kg 100% O2 8 deep breaths within 60 seconds at 10 L/min Always ensure pulse oximetry on patient Positioning Optimal Position – “sniffing position” Flexion of the neck and extension of the antlantooccipital joint Mandible and Floor of Mouth Optimal position: flexing neck and extending the atlantooccipital joint Positioning Positioning Factors that Interfere with Alignment Large teeth or tethered tongue Short mandible Protruding upper incisors Pathology in floor of mouth Reduced size of intra and sub mandibular space Practical Note: Thyromental distance 6 cm or 3 finger breaths should show Normal mandible Visualization Visualization Insert blade into mouth Sweep to right side and displace tongue to the left Advance the blade until it lies in the valeculla and then pull it forward and upward using firm steady pressure without rotating the wrist Avoid leaning on upper teeth May need to place pressure on cricoid to bring cords into view Visualization Visualization Laryngoscopy Grade Grade Grade Grade Grade I - 99% II - 1% III - 1/2000 IV - 1/ 10,000 Insertion Insert cuff to ~ 3 cm beyond cords Tendency to advance cuff too far Right mainstem intubation Cuff Inflation Inflate to 20 cm H2O Listen for leak at patients mouth Over inflation can lead to ischemia of trachea Confirmation ETT Position Continuous CO2 monitoring or capnometry Gold standard Must have at least 3 continuous readings without declining CO2 False Negative Results Tube in Trachea, Capnogram Suggests Tube in Esophagus Concurrent PEEP with ETT cuff leak Severe Airway obstruction Low Cardiac Output Severe hypotension Pulmonary embolus Advanced pulmonary disease False Positive Results Tube NOT in trachea, capnogram suggests tube in trachea Bag/valve/mask ventilation prior to intubation Antacids in stomach Recent ingestion of carbonated beverages Tube in pharynx False Positive Results Other Methods to Determine Placement of ETT tube Auscultation Visualization of tube through cords Fiberoptic bronchoscopy Pulse oximetry not improving or worsening Movement of the chest wall Condensation in ET tube Negative Pressure Test CXR Airway Maneuvers BURP – Improves visualization of airway 1. 2. 3. 4. Posterior pressure on the larynx against cervical vertebrae (Backward) Superior pressure on the larynx as far as possible (Upward) Lateral pressure on the larynx to the right (Right) With pressure (Pressure) Causes of Failed Intubation Poor positioning of the head Tongue in the way Pivoting laryngoscope against upper teeth Rushing Being overly cautious Inadequate sedation Inappropriate equipment Unskilled laryngoscopist Summary 600 patients die per year from complications related to airway management 3 mechanisms of injury: 1. 2. 3. Esophageal intubation Failure to ventilate Difficult Intubation Indication for intubation: 1. Ventilatory Support 2. Decreased GCS 3. Protection of Airway 4. Ensuring Airway patency 5. Anesthesia and surgery 6. Suctioning and Pulmonary Toilet 7. Hypoxic and Hypercarbic respiratory Failure 8. Pulmonary lavage Massive Hemoptysis Massive Hemoptysis More than 300 to 600 ml of blood in 12 to 24 hours. Difficult to assess the actual amount. Life threatening bleeding into the lung can occur without actual hemoptysis. Causes of Hemoptysis and Pulmonary Hemorrhage Localized bleeding Diffuse Bleeding Localized Bleeding Infections Bronchitis Bacterial Pneumonia Streptococcus and Klebsiella Tuberculosis Fungal Infections Aspergillus Candida Bronchiectasis Lung Abscess Leptospirosis Tumors Bronchogenic Necrotizing parenchymal cancer Squamous Adenocarcinomas Bronchial adenoma Cardiovascular Mitral Stenosis Localized Bleeding Pulmonary Vascular Problems Pulmonary AV malformations Rendu-Osler-Weber Syndrome Pulmonary embolism with infarction Behcet syndrome Pulmonary artery catheterization with pulmonary artery rupture Trauma Others Broncholithiasis Sarcoidosis (cavitary lesions with mycetoma) Ankylosing spondylitis Diffuse Bleeding Drug and chemical Induced Anticoagulants D-penicillamine (seen with treatment of Wilson’s disease) Trimellitic anhydride (manufacturing of plastics, paint, epoxy resins) Cocaine Propylthiouracil Amiodarone Phenytoin Hemosiderosis Blood dyscrasias Thrombotic thrombocytopenic purpura Hemophilia Leukemia Thrombocytopenia Uremia Antiphospholipid antibody syndrome Pulmonary – Renal Syndrome Goodpasture syndrome Wegener granulomatosis Pauci-immune vasculitis Diffuse Bleeding Vasculitis Pulmonary capillaritis With or without connective tissue disease Polyarteritis Churg-Strauss syndrome Henoch-Schonlein Purpura Necrotizing vasculitis Connective Tissue diseases Systemic lupus erythematosus Rheumatoid arthritis Mixed connective tissue disease Scleroderma (rare) Key Major Etiologies Tuberculosis Bronchiectasis Cancer Mycetoma Iatrogenic causes Alveolar Hemorrhage Trauma Vascular malformation Pulmonary embolism Other Infectious Causes Pathophysiology Bronchial circulation High (systemic) pressure circulation Drains into the right atrium (extrapulmonary bronchi) Also drains into pulmonary veins (intrapulmonary bronchi) Anterior spinal artery may originate from bronchial artery (5% of cases) Pulmonary circulation Low-pressure circulation Multiple anastomoses exist between bronchial and pulmonary circulations Clinical Findings Hemoptysis, Dyspnea, Cough, Anxiety Fever, weight loss Smoking and Travel history Bloody sputum Frothy blood – sputum mixture Bright red Alkaline Tachypnea, respiratory distress Localized wheezing, rales, poor dentition Digital clubbing Hematuria Differential Diagnosis Upper GI Bleeding Dark blood Food particles Acid pH Consider endoscopy Upper airway bleeding Examine mouth, nose, and pharynx. Laboratory Tests No specific tests CBC, diff, INR, PTT, platelet count Electrolytes, BUN, Cr Sputum culture and AFB Urinalysis ECG ABG’s Type and Screen Imaging Studies Chest X-ray Normal suggests endobronchial or extrapulmonary source. Potentially misleading Aspiration from distant source Chronic changes unrelated to acute event CT scan Useful in stable patients Can detect bronchiectasis Stabilization Ensure adequate ventilation and perfusion. Most common cause of death is asphyxia. Place patient in Trendelenburg position to facilitate drainage. Lateral decub – Bleeding side down Prevent contamination of good lung. Treatment General Measures: 1. 2. 3. 4. 5. 6. Place bleeding lung down to prevent aspiration into good lung Supplemental oxygen Avoid Sedation Correct coagulopathy and thrombocytopenia Consult pulmonary, critical care, and thoracic surgery Consider early involvement of anesthesia and interventional radiology Primary Goal is Airway Control Asphyxiation, not blood loss, is the cause of death. Only stable patients with ability to protect and clear their own airway should be managed without intubation. Intubation: Performed by experienced personnel. Large bore tube for bronchoscopy and suctioning. Consider bronchial blocker or double lumen tube if bleeding site is known. Secondary Goal is Localization of Bleeding Bronchoscopy required. Intubate prior to bronchoscopy. Rigid bronchoscopy May facilitate better suctioning. Inability to visualize beyond main stem bronchi and need thoracic surgeon. Bronchoscopic Interventions Bronchial blocker or Fogarty balloon catheter to occlude bleeding lung, lobe, or segment. Topical coagulants: Fibrin or fibrinogen-thrombin solution. Topical transexamic acid Consider Nd:YAG laser coagulation, electrocautery, or argon plasma coagulation. Lavaged iced saline Topical epinephrine Unilateral Lung Ventilation Single lumen tube advanced into main stem bronchus. Double lumen tube: Protects non-bleeding lung. Use left sided tube to prevent occlusion of Right upper lobe. May be difficult to position. Individual lumens too small for standard bronchoscope. Airway obstruction frequent problem. Displacement can lead to sudden asphyxiation. Patient should be therapeutically paralyzed and not moved. Bronchial Arteriography and Embolization Favored initial approach if facilities and expertise available. High success rate: approximately 90% when a bleeding vessel is identified. Recurrence rate: 10 – 27% 10% of patients bleed from the pulmonary circulation (TB or mycetoma). Serious complications: Occlusion of the anterior spinal artery with paraplegia. Embolic infarction of distal organs. Early Surgical Treatment Offers definitive treatment. Indicated for lateralized massive life-threatening hemoptysis, or failure or recurrence after other interventions. Contraindications: Poor baseline respiratory function. Inoperable lung carcinoma. Inability to localize bleeding site. Diffuse lung disease (relative) eg. CF. Mortality is higher if bleeding is acute Late Surgical Treatment Indicated for definitive treatment of underlying lesion, once bleeding subsided. Indications: Mycetoma Resectable carcinoma Localized bronchiectasis Prognosis Factors likely affecting outcome Etiology of hemoptysis Underlying co-morbid illnesses Surgical vs. medical treatment Mortality Medical mortality: 17 – 85% Estimated early surgical mortality: 0 – 50% Most case series reports preceded the development of angiographic embolization. Conclusion More than 300 to 600 ml of blood in 12 to 24 hours. Major causes: Tuberculosis Bronchiectasis Cancer Mycetoma Iatrogenic causes Alveolar Hemorrhage Trauma Vascular malformation Pulmonary embolism Primary goal is airway control followed by bleeding localization.