All I need is an LMA Narasimhan Sim Jagannathan, M.D. Associate Chairman, Academic Affairs Director, Pediatric Anesthesia Research Ann & Robert H. Lurie Children s Hospital of Chicago Associate Professor of Anesthesiology Northwestern University Feinberg School of Medicine Chicago, IL USA
Disclosures 1. Mercury Medical (air-q ): Product support for research and unpaid consultant for design 2. Teleflex ( LMA Unique, ProSeal, and Supreme): Product support for research and unpaid consultant for design and Medical advisory board 3. Ambu (Aura Gain & King Vision VL): Product support for research and unpaid consultant for design
Objectives Describe the various uses of supraglottic airways (SGAs) for difficult airway management (airway rescue, maintenance of anesthesia, out of hospital airway management) Know the advantages of SGAs for children with difficult airways vs other alternative airway devices Case examples
Why a use supraglottic device vs intubation in difficult airways? 1. Provide rapid oxygenation Speed of establishing a patent airway is faster 2. They are a more practical choice 3. Less invasive & easy to place Even in unskilled clinicians 4. Various ventilation options 5. Airway rescue Difficult mask ventilation Difficult laryngoscopy
Kelly CJ et al. Perioperative pulmonary aspiration is infrequent and low risk in pediatric anesthetic practice. Pediatr Anesth 2014 In children: Use of SGAs may be greater than the adult population (a lot still unknown): 1. Greater number of medical procedures done with anesthesia GI, MRI, CT, Heme Onc 2. Short duration high turnover procedures Urology, general surgery, ENT Children with difficult airways present for these surgeries 3. Aspiration risk is less than adults Currently: 30-50% of anesthetics are done under SGAs in children's hospitals Future: Majority of anesthetics can be under SGA anesthesia
SGA: Mechanism of airway seal An adequately placed device forms 2 seals: 1. A peri-laryngeal seal 2. A hypopharyngeal seal Leading edge occludes esophagus Better with 2 nd generation devices (gastric tube) 6
The reality Pediatric anesthesiologists routinely utilize SGAs in a variety of challenging scenarios: Difficult airway Remote locations Long-duration surgeries Prone procedures Under-reported use of SGAs in the literature Patel A et al. Pediatr Anaesth. 2015:1127-31
Mathis M. Anesthesiology 2013:1284-95 Risk factors for failure of SGA in children Mixed population of children in a tertiary care center Retrospective: 11,910 cases 102 cases (0.86%) experienced LMA failure Failure rates are less than in adults Increased risk associated with: 1. Ear/nose/throat surgical procedures 2. Inpatient status 3. Prolonged surgical duration 4. Airway abnormalities 5. Patient transport
Children are ideal candidates to receive an SGA for anesthesia They need rapid/early oxygenation Low Aspiration Risk High success rates of SGA placement Low lung compliance Low failure rates Undergo several minor procedures Jagannathan N. et al Pediatr Anesth. 2015:334-45
Bottom line: Most problems associated with SGA failure has to do with: Inadequate anesthesia Poor patient selection Dogmatic anesthetic practice
So why are clinicians hesitant to use SGAs more frequently? Unhappy surgeon My trainee sucks Fear Stubborn: It wont work Aspiration Unfamiliarity Jagannathan N. et al Pediatr Anesth. 2015:334-45
Difficult airways
Difficult airways in children 13 pediatric centers MOST COMMON COMPLICATION WAS HYPOXIA MOST COMMON MAJOR COMPLICATION WAS CARDIAC ARREST WERE THESE HYPOXEMIC EVENTS PREVENTABLE?? Fiadjoe JE, Nishasaki A, Jagannathan N, et al.severe outcomes in children with challenging tracheal intubation: A prospective multicenter Analysis: The Lancet Respiratory Medicine 2016
1018 cases 222 complications (22%) Severe 3% Cardiac Arrest 1 in 68 pts Non Severe 19% RISK FACTORS: 1. Weight <10kg 2. Short TM distance (micrognathia) 3. Persistent DL More than 2 attempts First 3 attempts are DL COMPLICATIONS Fiadjoe JE, Nishasaki A, Jagannathan N, et al.severe outcomes in children with challenging tracheal intubation: A prospective multicenter Analysis: The Lancet Respiratory Medicine 2016
Primary technique by device Device Direct Laryngoscopy 1 st Attempt <10 kg 1 st Attempt >10kg Overall success 13.1% 12% 25% GlideScope 38% 57.4% 86% Fiberoptic (free-handed) 41.2% 48.5% 94% Fiberoptic through SGA 48% 58.5% 98% Fiadjoe JE, Nishasaki A, Jagannathan N, et al.severe outcomes in children with challenging tracheal intubation: A prospective multicenter Analysis: The Lancet Respiratory Medicine
What can we interpret from these results of the PediR Children <10kg are high risk of complications Oxygenation is important to prevent complications associated with airway management Regardless of the device used Devices fail Multiple attempts are BAD More studies in specific difficult airway populations are needed to define best airway management practices
Questions not answered by the PediR Could early use of an SGA avoid hypoxemic complications? Using SGA in between attempts Using SGA after failed device What about an SGA as a primary strategy for difficult airways? PeDIR data: 17% poor ventilation 2% impossible placement SGAs were used after multiple attempts with other devices difficult to make definitive conclusions
Difficult airways In 96% of children with difficult airways: SGA was used successfully without intubating the trachea Plan A(SGA alone) & Plan B (FOI) in one airway management strategy
In another words In difficult airways: SGAs fail 4% of the time Both VL and fiberoptic have overall higher failure rates than SGAs YOU CANNOT EFFECTIVELY OXYGENATE WITH VL OR FIBEROPTIC
Clinical translation of lessons learned from the PediR study Oxygenation is important during airway management Most hypoxemic events may have been preventable DL is a poor technique in children with difficult airways Use an advanced alternative airway technique early if DL fails USE OF AN SGA MAY HAVE PREVENTED SOME OF THESE COMPLICATIONS
Key points Use of an SGA is a distinct step in virtually all airway algorithms
Canadian Airway Focus Group
New Zealand SGAs should be tried 3 times before surgical airway
Key point Insert an SGA when there is: Failed laryngoscopy Difficult mask ventilation
Supraglottic airway & the difficult airway SGA s: Possible to manage the difficult airway patient with SGA alone Goldenhar syndrome Overcomes upper airway obstruction Option to quickly intubate the trachea via SGA (high success rates)
Case: Pierre Robin baby
Awake Supraglottic device Advantages: 1. Well tolerated 2. Overcomes upper airway obstruction Preserves spontaneous ventilation Improves oxygenation 3. No increase in aspiration risk Pierre Robin syndrome Asai T, et al. Pediatr Anesth. 2008 Jagannathan N,et al. Anaesthesia. 2013 Stricker PA, et al. Acta Anesthesiologica Scand.2009 YOU CANNOT OVERCOME AIRWAY OBSTRUCTION WITH A FIBEROPTIC OR VIDEOLARYNGOSCOPE
AWAKE SGA in infants with airway obstruction STEP 1 Administer an antisialagogue agent Lidocaine jelly applied by finger to the posterior pharnyx Topicalize with 2% lidocaine jelly: by finger or pacifier technique Jagannathan N, Sohn LE, Eidem J. Anaesthesia 2013
Step 2: Insert SGA
Step 3: After insertion: Make adjustments if needed
Step 4: Verify glottic position Plan B: Option to intubate if needed
Case: 1 month old with cervical spine injury from a fall Philadelphia collar Unstable C spine MRI and Head CT SGA vs TT?
180 minutes later..
Case: 2 day old neonate with Pierre Robin for CT craniofacial SPO2 80s in supine position Prone position improves oxygenation
SGA and prone insertion SGA inserted awake in prone position Airway obstruction improves and turned supine for the CT/MRI scan Anesthesia induced with sevoflurane via SGA Removed awake at the end of procedure
Important point SGA use in difficult airways when used as the primary airway: Requires an advanced airway skill set: Able to act swiftly to troubleshoot problems Intubate the trachea if needed in the middle of dynamic changes This practice is not for everyone Jagannathan N, Sohn L, Fiadjoe JE. Br J Anaesth 2016 (Editorial)
Important point The SGA should not be used to AVOID tracheal intubation without a back up (bail out) plan When an SGA is placed you already have plan B in place (use of a fiberoptic) Cook TM et al. Br J Anaesth. 2011:632-42
Special scenarios in difficult airways
Airway rescue
Case: Dwarf for Spinal Fusion An obese 11-year old, 39 kg (105 cm) female achondroplastic dwarf with kyphosis was scheduled to undergo a T7-12 posterior spinal fusion with posterior vertebral resection spine osteotomy and instrumentation. Restrictive lung disease OSA= BiPAP at night Her airway examination revealed course facial features, limited mouth opening, short neck, and macroglossia
Airway management Anesthesia induced Easy BMV Direct laryngoscopy with a Miller blade revealed no clear view of the larynx No adequate view of the larynx with a GlideScope (limited mouth opening) Intubated through SGA (air-q) and fiberoptic bronchoscope
Intra-operatively: 5 hours later Surgeon requests a wake up test for poor SSEP signals Back is partially instrumented with several screws Head abruptly moves and ETT is dislodged between prone view pillow Rapid oxygen desaturation 60s What would you do?
The most appropriate next step for airway management is to perform: a) Direct laryngoscopy b) Fiberoptic intubation c) GlideScope intubation d) SGA insertion
SGA for airway rescue: Prone difficult airway during spinal fusion Sohn L, Sawardekar A, Jagannathan N Can J Anesth 2014
News Flash You cannot rapidly rescue the airway with any advanced airway devices e.g.) GlideScope or Fiberoptic Bronchoscope You cannot effectively oxygenate with a GlideScope or Fiberoptic Bronchoscope
Failed intubation
Great view with VL, but Video courtesy of Dr James Du Canto, MD
Failed intubation with VL Video courtesy of Dr James Du Canto, MD
Take home point If an advanced device fails (e.g. Fiberoptic/ videolaryngoscope) the next logical step should be placement of an SGA
Out of hospital
Out of hospital cardiac arrest: adults SGA vs ETT for out of hospital cardiac arrest Primary outcome measure: one-month survival with neurologically favorable outcome There was no difference in outcome between devices Early oxygenation regardless of type of device was associated with improved outcomes Hasegawa K et al. JAMA 2013:257-66 Kajino K Crit Care 2011
Conclusions SGAs can be used safely and effectively in MOST patients Even in the difficult airway Effective in rapid oxygenation Key to success is proper patient selection and advanced skill sets to bail yourself out if needed Greater multi-center evidence is needed for more widespread use