Airway management
Anatomy and Physiology The airways can be divided in to parts namely: The upper airway. The lower airway.
Non-instrumental airway management
Head Tilt and Chin Lift
Jaw Thrust
Advanced Airway Management & Intubation
Advantages of Endotracheal Intubation Cuffed E.T tubes protect the airway from aspiration. E.T tube provides access to the tracheobronchial tree for suctioning of secretions. E.T tube does not cause gastric distention and associated danger of regurgitation. E.T tube maintains a patent airway and assists in avoiding further obstruction. E.T tube enables delivery of aerosolized medication.
Indications for Intubation Inadequate oxygenation(decreased arterial PO2) that is not corrected by supplemental oxygen via mask/nasal. Inadequate ventilation (increased arterial PCO2). Need to control and remove pulmonary secretions. Any patient in cardiac arrest.
Indications for Intubation Ant patient in deep coma who cannot protect his airway.(gag reflex absent.). Any patient in imminent danger of upper airway obstruction (e.g. Burns of the upper airways). Any patient with decreased L.O.C, GCS <= 8. Severe head and facial injuries with compromised airway.
Indications Cont Any patient in respiratory arrest Respiratory failure refractory to O2 1. Hypoventilation/Hypercarbia A. Paco2 > 55mmhg 2. Arterial hypoxemia A. Paco2 < 70 on 100% O2
Contraindications for Intubation Patients with an intact gag reflex. Patients likely to react with laryngospasm to an intubation attempt. e.g. Children with epiglottitis. Basilar skull fracture avoid naso-tracheal intubation and nasogastric/pharyngeal tube.
Laryngoscopes
Equipment for intubation Laryngoscope with relevant size blades. Magill forceps. Flexible introducer. 10-20 ml syringe. Oropharangeal airways all sizes. Tape or adhesive plaster. E.T tubes relevant sizes. Bag-valve-mask with oxygen connected. Suction unit with Yankauer nozzle and endotracheal suction catheter.
Technique of Endotracheal Intubation
Technique Cont Position the patient supine, open the airway with a head-tilt chin-lift maneuver.(suspected spinal injury, attempt naso-tracheal intubation, spine in neutral position.). Open mouth by separating the lips and pulling on upper jaw with the index finger. Hold laryngoscope in left hand, insert scope into mouth with blade directed to right tonsil. Once right tonsil is reached, sweep the blade to the midline keeping the tongue on the left.
Technique Cont This brings the epiglottis into view. DO NOT LOOSE SIGHT OF IT! Advance the blade until it reaches the angle between the base of the tongue and epiglottis.( volecular space) Lift the laryngoscope upwards and away from the nose towards the chest. This should bring the vocal cords into view. It may be necessary for a colleague to press on the trachea to improve the view of the larynx. Place the ETT in the right hand. Keep the concavity of the tube facing the right side of the mouth. Insert the tube watching it enter through the cords.
Technique Cont Insert the tube just so the cuff has passed the cords and then inflate the cuff. Listed for air entry at both apices and both axillae to ensure correct placement using a stethoscope.
Insertion of tracheal tube
Rules of Intubation Always have a suction unit available. An intubation attempt should never exceed 30 seconds. Oxygenate the patient pre and post intubation with a bag-valve-mask.(100% O2). Have sedative medication available if needed. (e.g. Midazolam 15mg/3ml) Always recheck tube placement manually guided by oxygen saturation readings.(spo2).
Tube sizes Newborn to 4 kg - 2.5 mm (uncuffed). 1-6 months 4-6 kg 3.5 mm (uncuffed). 7-12 months 6-9 kg 4.0 mm (uncuffed). 1 year 9 kg 4.5 mm (uncuffed). 2 years 11 kg 5.0 mm (uncuffed). 3-4 years 14 16 kg - 5.5 mm (uncuffed). 5-6 years 18 21 kg 6.0 mm (uncuffed). 7-8 years 22-27 kg 6.5 mm ( uncuffed).
Tube Sizes 9-11 years 28-36 kg 7.0 mm(cuffed). 14 to adults 46+ kg 7.0 80 mm (cuffed). Adult female 7.0 8.0mm (cuffed). Adult male 7.5 8.5 mm (cuffed). The size of the tube may also be determined by the size of the patients little finger. N.B patients below the age of 8 require uncuffed ETT due to damage caused by the cuff in younger patients. Always monitor the ECG activity during intubation.
Complications Associated With Intubation Trauma of the teeth, cords, arytenoid cartilages, larynx and related structures. Nasotracheal tubes can damage the turbinates, cause epistaxis, and even perforate the nasopharyngeal mucosa. Hypertension and tachycardia can occur from the intense stimulation of intubation; This is potentially dangerous in the patient with coronary heart disease. Transient cardiac arrhythmias related to vagal stimulation or sympathetic nerve traffic may occur.
Complications Continued Damage to the endotracheal tube cuff, resulting in a cuff leak and poor seal. Intubation of the esophagus, resulting in gastric distention and regurgitation upon attempting ventilation. Baro-trauma resulting from over ventilating with a bag without a pressure release valve( phneumothorax).
Complications Continued Over stimulation of the larynx resulting in laryngospasm, causing a complete airway obstruction. Inserting the tube to deep resulting in unilateral intubation (right bronchus). Tube obstruction due to foreign material, dried respiratory secretion and/or blood.
Difficult intubation- ASA definition More than 2 attemps by experienced anesthesiologist Intubation lasting more than 10 minutes
Alternatives to ET tube Supraglottic Airway Devices (SAD)
LMA Insertion
Combitube
Advantages over intubation - 1 Blind insertion from any angle of approach No introducer tool required Limited use of muscle relaxants Non-invasive - LM s do not pass through a sphinctre Low-pressure seal
Advantages over intubation - 2 Not excessively associated with sore throats Not associated with post-operative nausea Not associated with morbidity Not associated with mortality Rapid post-operative recovery
Advantages of SAD Recommended for use in emergency including ALS! Can be inserted after short training by every medical professional Easy to learn good learning curve, good skills keeping