DIFFICULT AIRWAY IN THE ICU Dr Anitha Shenoy Professor and Head of Anaesthesiology Kasturba Medical College, Manipal
Difficult Airway In The ICU Hypoxic patient Cardiac arrest Equipment unavailability Insufficient training
Definitions Ref: ASA Taskforce Anesthesiology 2003; 98:1269–77
Difficult airway A clinical situation in which a conventionally trained anaesthesiologist experiences difficulty with face mask ventilation, tracheal intubation or both.
Difficult face mask ventilation It is not possible for the anesthesiologist to provide adequate face mask ventilation due to : inadequate mask seal excessive gas leak or excessive resistance to the ingress or egress of gas.
Signs of inadequate face mask ventilation include: Absent or inadequate chest movement / breath sounds Auscultatory signs of severe obstruction Gastric air entry or dilatation Decreasing or inadequate SpO 2 Absent or inadequate exhaled CO 2 and Haemodynamic changes associated with hypoxaemia or hypercarbia (e.g., hypertension, tachycardia, arrhythmia).
Difficult laryngoscopy It is not possible to visualize any portion of the vocal cords after multiple attempts at conventional laryngoscopy. Difficult tracheal intubation Tracheal intubation requires multiple attempts, in the presence or absence of tracheal pathology. Failed intubation Placement of the endotracheal tube fails after multiple intubation attempts.
Assessment
ASSESSMENT OF AIRWAY History and Physical examination: To detect medical, surgical and anaesthetic factors hinting a difficult airway. Previous anesthetic records The test: One finger into the temporomandibular joint Two-finger breadths’ distance between the upper and lower incisors Three-finger breadths’ distance from the chin to the thyroid cartilage.
Modified Mallampati Classification of the airway
These classes roughly correlate with the following grades of laryngoscopic views. Difficult intubation is anticipated with Mallampati Class III and IV. Modified Cormack and Lehane grading of laryngoscopic view
Neck movements Goniometer
Full range of neck movements > 90° - Normal ° - Slight restriction < 80° - Severe restriction
Neck Extension Grade I : > 35° Normal Grade II : 22°-34° Grade III : 12°-21° Grade IV : < 12°
Anticipated Difficult mask ventilation
Anticipated Difficult Intubation
Anticipated difficult intubation
Anticipated difficult intubation - Awake
Anticipated difficult intubation
Anticipated difficult intubation - Awake Choices for intubation Flexible fibreoptic intubation Blind nasal intubation Retrograde intubation Tracheostomy (Take consent in advance)
Unanticipated difficult intubation - A naesthetised Can ventilate, difficult to intubate Essentially Same as Before !!!
Plan D Plan C Plan BPlan A
Anticipated difficult intubation - A naesthetised
Plan A Initial tracheal intubation plan Direct Laryngoscopy Tracheal intubation Succeed Failed intubation Plan B Variety of laryngoscopes, endotracheal tube guides, lighted stylets Anticipated difficult intubation - A naesthetised
Direct Rigid laryngoscopes CLM Laryngoscope
Direct Rigid laryngoscopes Glidescope
Indirect Rigid laryngoscopes Bullard Laryngoscope Upsher Laryngoscope
Endotracheal tube guides Gum Elastic Bougie Frova Introducer Aintree Introducer Cook Airway Exchange Flextip Catheter
Lighted stylets Trachlight Bonfils Shikani Optical Stylet (SOS)
Plan B Secondary tracheal intubation plan ILMA, LMA Confirm, FOB guided tracheal intubation Succeed Failed oxygenation Plan C Variety of supraglottic airways Anticipated difficult intubation - A naesthetised
Supraglottic airway devices Intubating Laryngeal Mask Airway (ILMA) ProSeal Laryngeal Mask Airway (PLMA)
Supraglottic airway devices Ambu Laryngeal Mask Airway
Supraglottic airway devices Combitube®
Supraglottic airway devices Laryngeal Tube Pharyngotracheal Lumen Airway (PLA)
Plan C Maintenance of oxygenation, ventilation, postponement of surgery and awakening Revert to face mask, oxygenate and ventilate Postpone surgery Failed oxygenation Succeed Plan D Variety of supraglottic airways Anticipated difficult intubation - A naesthetised
Plan D Rescue techniques for ‘can’t intubate, can’t ventilate’ situation LMA Awaken patient Improved oxygenation Increasing hypoxaemiaCricothyroidotomy Variety of infraglottic airways Anticipated difficult intubation - A naesthetised
Unanticipated difficult intubation - A naesthetised Cannot ventilate, cannot intubate
Failed intubation and difficult ventilation Face mask Oxygenate and ventilate Maximum head extension Maximum jaw thrust Assistance with mask seal Oral 6 mm nasal airway Reduce cricoid force – If necessary Call for help !!! Unanticipated difficult intubation - A naesthetised Cannot ventilate, cannot intubate Failed oxygenation with face mask ? (SpO 2 > 90%) with FIO 2 = 1
Cannot intubate, cannot ventilate … ILMA, LMA Oxygenate and ventilate patient Maximum 2 attempts at insertion Reduce any cricoid force during insertion Succeed Oxygenation satisfactory and stable: Maintain oxygenation and awaken patient Cannot intubate, Cannot ventilate Plan D
Plan D: Rescue techniques for ‘cannot intubate, cannot ventilate’ situation Cricothyroidotomy Needle Cannula Surgical Increasing hypoxaemia Variety of infraglottic airways Cannot intubate, cannot ventilate …
Infraglottic airway devices Enk Oxygen Flow Modulator
Infraglottic airway devices Melker Cricothyrotomy Cannula Arndt’s Cricothyrotomy set
Infraglottic airway devices Quicktrach
Unanticipated difficult intubation – A naesthetised and full stomach
Plan A Initial tracheal intubation plan Direct Laryngoscopy Failed intubation Tracheal intubation Succeed Plan C (Face mask) Maintenance of oxygenation, ventilation, postponement of surgery and awakening No Plan B ProSeal LMA ?
Unanticipated difficult intubation – A naesthetised and full stomach Plan D Rescue techniques Increasing hypoxaemiaCricothyroidotomy Variety of infraglottic airways LMA Improved oxygenation Awaken patient
Oxygenate Visualisation Ventilation Intubation Oxygenation Chain of survival for the airway VIVO
Infraglottic airway obstruction ??
Approach to Difficult Airway
Difficult Airway Equipment Direct laryngoscopes Indirect laryngoscopes Endotracheal tube guides Lighted stylets Supraglottic airway devices Infraglottic airway devices
Difficult airway cart
Pulse oximetry Capnography
Difficult airway trainers Sheep trachea Critical Airway Management Trainer
Medic Alert !!!