Airway during CPR

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A brief description of managing Airway during CPR, as per AHA 2010 guidelines.

A brief description of managing Airway during CPR, as per AHA 2010 guidelines.

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  • As described by Sellick in 1961,
  • The compressing provider should give continuous chest compressions at a rate of at least 100 per minute, without pauses for ventilation. The provider delivering ventilation should provide 1 breath every 6 to 8 seconds (8 to 10 breaths per minute)
  • Both are ET tubes.
  • Both are ET tubes.

Transcript

  • 1. Moderator :- Dr. Raksha KundalPresenter :- Dr. Abhinav Gupta
  • 2. CPR is a series of lifesaving actions that improve thechance of survival following cardiac arrest.Successful resuscitation requires an integrated set ofcoordinated actions represented by the links in theChain of Survival.1. Immediate recognition and assistance.2. Early CPR with an emphasis on chest compressions3. Rapid defibrillation4. Effective advanced life support5. Integrated post–cardiac arrest care
  • 3. Overview of Airway Management…The purpose of ventilation during CPR is to maintain adequateoxygenation and sufficient elimination of CO2.The optimal Volume, Rate, and Oxygen Concentration for resuscitationis not identified as yet.Because of substantially reduced systemic and pulmonary perfusions, anormal ventilation-perfusion relationships can be maintained with aminute ventilation much lower than normal ventilation.During CPR with an advanced airway in place, a lower rate of rescuebreathing is needed to avoid hyperventilation.
  • 4. Ventilation and Oxygenation...During low blood flow statessuch as CPROxygen delivery to the heart and brain is limited by blood flowRather than by arterial oxygen content.ThusRescue breaths are less important than chest compressions during thefirst few minutes of resuscitation.Further,This can reduce CPR efficacy due to1. Interruption in chest compressions and2. The increase in intra-thoracic pressure.Advanced airway placement in cardiac arrest should not delay initialCPR and defibrillation for VF cardiac arrest
  • 5. Oxygen Administration During CPR…The optimal inspired oxygen concentration during adult CPR has not beenestablishedand it is unknown whether 100% or titrated oxygen is better.Although prolonged exposure to 100% inspired oxygen has potentialtoxicity,there is insufficient evidence to indicate that this occurs during brief periodsof adult CPR.Empirical use of 100% inspired oxygen during CPR optimizes arterial oxy-hemoglobin content and in turn oxygen delivery;Therefore, use of 100% inspired oxygen as soon as it becomes availableis reasonable during resuscitation from cardiac arrest
  • 6. Passive Oxygen Delivery During CPR …Positive-pressure ventilation has come under scrutiny because of the potential forincreased intra-thoracic pressure.When passive oxygen delivery using a fenestrated tracheal tube (Boussignac tube)during uninterrupted physician managed CPR was compared with standardCPR, there was no difference in oxygenation, ROSC, or survival to hospitaladmission.**Chest compressions expel air from chest, and oxygen is drawn passively due to theelastic recoil of the chest.In theory, because of lower ventilation requirements during cardiac arrest, oxygensupplied by passive delivery may be sufficient for several minutes with a patentupper airway.At this time there is insufficient evidence to support the removal of ventilationsfrom CPR performed by ACLS providers.** Saissy JM, Boussignac G, et. al. Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression duringout-of-hospital cardiorespiratory arrest. Anesthesiology. 2000;92: 1523–1530.** Bertrand C, Hemery F, et.al. Constant flow insufflation of oxygen as the sole mode of ventilation during out-of hospital cardiac arrest.Intensive Care Med. 2006;32:843– 851
  • 7. Bag-Mask Ventilation…Bag-mask ventilation is an acceptable method of providing ventilation andoxygenation during CPR but is a challenging skill.It is not recommended for a lone provider, when mouth-to-mouth or mouth-to-mask are more efficient.It is most effective when performed by 2 trained and experienced providers.One provider opens the airway and seals the mask to the face while the othersqueezes the bag.The provider should be sure to open the airway adequately with a head tilt–chinlift, lifting the jaw against the mask and holding the mask against the face,creating a tight seal.
  • 8. Bag-Mask Ventilation…Bag-mask ventilation is particularly helpful when placement of an advancedairway is delayed or unsuccessful.The provider should use an adult (1 to 2 L) bag and deliver approximately 600mL of tidal volume sufficient to produce chest rise over 1 second.This volume of ventilation is adequate for oxygenation and minimizes the riskof gastric inflation.Bag-mask ventilation can produce gastric inflation withcomplications, including regurgitation, aspiration, and pneumonia.Gastric inflation can elevate the diaphragm, restrict lung movement, anddecrease respiratory system compliance.
  • 9. Cricoid Pressure…“the manoeuver consists in temporary occlusion of the upper endof the oesophagus by backward pressure of the cricoid cartilageagainst the bodies of the cervical vertebrae … Extension of the neckand application of pressure on the cricoid cartilage obliterates theoesophageal lumen at the level of the body of the fifth cervicalvertebra … Pressure is maintained until intubation and inflation ofthe cuff of the endotracheal tube is completed.”Kopka and Herman and colleagues notedthat cricoid pressure was used as early as1774 to avert regurgitation related to gastricdistention with air during resuscitation fromdrowning.
  • 10. Cricoid PressureCricoid pressure in non-arrest patients may offer some measure ofprotection to the airway from aspiration and gastric insufflation during bag-mask ventilation.However, it also may impede ventilation and interfere with placement of asupraglottic airway or intubation.The role of cricoid pressure during out-of-hospital cardiac arrest and in-hospital cardiac arrest has not been studied.If cricoid pressure is used in special circumstances during cardiac arrest, thepressure should be adjusted, relaxed, or released if it impedes ventilation oradvanced airway placement.The routine use of cricoid pressure in cardiac arrest is not recommended
  • 11. Oropharyngeal AirwaysIf head extension and jaw thrust fail to maintain an unobstructedairway,options include insertion of an oropharyngeal airway, nasopharyngealairway, or SAD and tracheal intubation.An oropharyngeal airway is normally the first choice, provided thatsufficient mouth opening is possible.The airway should be inserted only when thepharyngeal and laryngeal reflexes aredepressed to minimize the risk of provokingcoughing and laryngospasm.The risk of damage to the teeth during theinsertion of oropharyngeal airways is increasedin the presence of caries and gingivitis.
  • 12. Oropharyngeal AirwaysAlthough studies have not specifically considered the use oforopharyngeal airways in patients with cardiac arrest, airways mayaid in the delivery of adequate ventilation with a bag-mask device bypreventing the tongue from occluding the airway.Incorrect insertion of an oropharyngeal airway can displace thetongue into the hypopharynx, causing airway obstruction.To facilitate delivery of ventilations with a bag-maskdevice, oropharyngeal airways can be used in unconscious(unresponsive) patients with no cough or gag reflex and should beinserted only by persons trained in their use.
  • 13. Nasopharyngeal AirwaysIf airway obstruction is not improved with the oropharyngeal airway, thenext step has traditionally been insertion of a nasopharyngealairway, which often dramatically improves the airway.The concavity is meant to follow the superior side of the hard palate andposterior wall of the naso-oropharynx. The airway is beveled on the leftside to aid in following the airway and minimizing mucosal trauma as itadvances.An ETT may be cut to the desired length,softened in hot water,as used in emergency.The cuff is blown up in the oropharynx orlaryngopharynx and the tube pulled back sothat the cuff lies against the soft palate anddisplaces the base of the tongue forward.
  • 14. Nasopharyngeal AirwaysNasopharyngeal airways are useful in patients with airway obstruction orthose at risk for developing airway obstruction,particularly when conditions such as a clenched jaw prevent placementof an oral airway.Further nasopharyngeal airways are better tolerated than oral airways inpatients who are not deeply unconscious.Airway bleeding can occur in up to 30% of patients following insertionof a nasopharyngeal airway.In patients with base of skull fracture, intra-cranial placement is a hazardtoo be taken care of.**In the presence of known or suspected basal skull fracture or severecoagulopathy, an oral airway is preferred.** Schade K, et.al. Intracranial malposition of nasopharyngeal airway. J Trauma. 2000;49:967–968.** Muzzi DA, et.al. Complication from a nasopharyngeal airway in a patient with a basilar skull fracture.Anesthesiology.1991;74:366 –368.
  • 15. Advanced AirwaysVentilation with a bag and mask or with a bag through an advancedairway (eg, endotracheal tube or supraglottic airway) is acceptableduring CPR.Because there are times when ventilation with a bag-mask device isinadequate, ideally ACLS providers also should be trained andexperienced in insertion of an advanced airway.Although insertion of an endotracheal tube can be accomplishedduring ongoing chest compressions, intubation frequently isassociated with interruption of compressions for many seconds.Placement of a supraglottic airway is a reasonable alternative toendotracheal intubation and can be done successfully withoutinterrupting chest compressions.
  • 16. Advanced AirwaysThe provider should weigh the need for minimally interruptedcompressions against the need for insertion of an endotracheal tube orsupraglottic airway.There is inadequate evidence to define the optimal timing of advancedairway placement in relation to other interventions during resuscitationfrom cardiac arrest.In a registry study of 25 006 in-hospital cardiac arrests, earlier time toinvasive airway (5 minutes) was not associated with improvedROSC, but was associated with improved 24-hour survival.31 In an out-of-hospital setting, intubation that was achieved in 12 minutes wasassociated with better survival than intubation achieved in 13 minutes.****Wong ML,et.al. Time to invasive airway placement and resuscitation outcomes after inhospital cardiopulmonary arrest. Resuscitation.2010;81:182–186.** Shy BD, et.al. Time to intubation and survival in prehospital cardiac arrest. Prehosp Emerg Care. 2004;8: 394–399.
  • 17. Advanced AirwaysIt has been seen that delayed endotracheal intubation combined with passiveoxygen delivery and minimally interrupted chest compressions wasassociated with improved neurologically intact survival after out-of-hospitalcardiac arrest in patients with adult witnessed VF/pulseless VT. **In out-of-hospital settings, patients intubated during resuscitation had abetter survival rate, whereas in an indoor setting, patients requiringintubation during CPR had a worse survival rate.##If advanced airway placement will interrupt chest compressions, providersmay consider deferring insertion of the airway until the patient fails torespond to initial CPR and defibrillation attempts or demonstrates ROSC**Bobrow BJ, et.al. Passive oxygen insufflation is superior to bag-valve-mask ventilation for witnessed ventricular fibrillation out-of-hospitalcardiac arrest. Ann Emerg Med. 2009;54: 656–662.##Jennings PA, et.al. Out-ofhospital cardiac arrest in Victoria: rural and urban outcomes. Med J Aust. 2006;185:135–139.##Dumot JA, et.al. Outcome of adult cardiopulmonary resuscitations at a tertiary referral center including results of “limited” resuscitations. ArchIntern Med. 2001;161:1751–1758.
  • 18. Advanced AirwaysFor a patient with perfusing rhythm who requires intubation, pulseoximetry and electrocardiographic (ECG) status should be monitoredcontinuously during airway placement.Intubation attempts should be interrupted to provide oxygenation andventilation as needed. Providers should have a second (backup) strategyfor airway management and ventilation. Bag-mask ventilation may serveas that backup strategy.Once an advanced airway is inserted, providers should immediatelyperform a thorough assessment to ensure that it is properly positioned.This assessment should not interrupt chest compressions. This includesobservation of chest compressions, auscultation and capnography.
  • 19. Supra-Glottic AirwaysBecause the placement of a supraglottic device does not require directvisualisation of the glottic opening,placement is possible without interrupting cardiac compressions.Also, due to same reasons, placement by paramedics and emergencyteam out of hospital has a steeper learning curve and better success rate.It is important to remember that there is no evidence that advancedairway measures improve survival rates in the setting of out-ofhospital cardiac arrest.During CPR performed by providers trained in its use, the supraglotticairway is a reasonable alternative to bag-mask ventilation, andendotracheal intubation.
  • 20. Esophageal-Tracheal TubeA tube with a closed distal end that is designed for passage into theesophagus is common to all esophageal obturator devices.A distal seal in the esophagus is provided by an inflatable cuff, and aproximal seal is achieved with a facemask or oropharyngeal cuff.Holes in the tube between the proximal seal and the distal cuff delivergases to the laryngopharynx.The Combitube has been widely used inprehospital care. The proximal seal is providedby an oropharyngeal cuff. It has a second open-ended tube that can function as a tracheal tube ifit is inadvertently inserted into the trachea. Itgives protection against regurgitation similar tothat provided by modern periglottic devices
  • 21. Esophageal-Tracheal TubeThe advantages of the Combitube are similar to Endotracheal tube :1. Isolation of the airway, 2. Reduced risk of aspiration,3. More reliable ventilation.The advantages of the Combi-tube over the endotracheal tube are relatedchiefly to ease of training. It has been observed that providers with all levels ofexperience are able to insert it and ventilation is comparable to endotrachealintubation.**Ventilation and oxygenation with combi-tube compare favorably with thoseachieved with the endotracheal tube too. In a retrospective study no differencein outcome was observed in patients treated either. ##Fatal complications may occur if the position of the distal lumen is identifiedincorrectly. For this reason, confirmation of tube placement is essential.Esophageal trauma may also occur.**Rabitsch et.al. Comparison of a conventional tracheal airway with the Combitube in an urban emergency medical services system run byphysicians. Resuscitation. 2003;57: 27–32.##Cady CE, et.al. Effect of emergency medical technician-placed Combitubes on outcomes after out-of hospital cardiopulmonary arrest.Prehosp Emerg Care. 2009;13: 495–499
  • 22. Laryngeal TubeA single-lumen esophageal obturator device in whichboth cuffs are inflated from a single inflation line,and the size and number of holes between the two cuffs have beenincreased.Placement is rapid and the incidence of laryngospasm and coughing islow.The LT achieves a high leak pressure, thusfacilitating higher airway pressure than withthe LMA classic (LMAc) during positive-pressure ventilationThe LT consists of a silicon reusable airwaytube provided with two cuffs (pharyngeal andesophageal), a single balloon for pressurecontrol
  • 23. Laryngeal TubeUnlike esophageal-tracheal tube, the laryngeal tube can only go intothe esophagus, and is more compact.Ventilation in studies has been found to be adequate in upto 85% ofpatients**, and a success rate of 97% in placement estimated.##Cases of cuff rupture, and aspiration due to regurgitation aredocumented.For healthcare professionals trained in its use, the laryngeal tube maybe considered as an alternative to bag-mask ventilation orendotracheal intubation for airway management in cardiac arrest.**Heuer JF et.al. Initial ventilation through laryngeal tube instead of face mask in out-of hospital cardiopulmonary arrest is effective and safe.Eur J Emerg Med. 2010;17:10 –15.##Schalk R, et.al. Out-of-hospital airway management by paramedics and emergency physicians using laryngeal tubes. Resuscitation. 2010;81:323–326
  • 24. Laryngeal Mask AirwaysThe laryngeal mask airway provides a more secure and reliable means ofventilation than the face mask.Studies have shown that regurgitation is less likely with the laryngealmask airway than with the bag-mask device and that aspiration isuncommon.When compared with the endotracheal tube, the laryngeal mask airwayprovides equivalent ventilation.Its simplicity in usage and application when patient access andpositioning is limited and in unstable neck injuries can not be overemphasized.After successful insertion, a small proportion of patients cannot beventilated with the laryngeal mask airway. With this in mind, it isimportant for providers to have an alternative strategy for airwaymanagement
  • 25. Endo Tracheal TubeThe endotracheal tube was once considered the optimal method ofmanaging the airway during cardiac arrest. However, intubation attemptscan produce complications, such as trauma to the oropharynx,interruption of compressions and ventilations for unacceptably longperiods, andhypoxemia from prolonged intubation attempts or failure to recognizetube misplacement or displacement.It is now clear that the incidence of complications is unacceptably highwhen intubation is performed by inexperienced providers or monitoringof tube placement is inadequate.The optimal method of managing the airway during cardiac arrest willvary based on provider experience, characteristics of the EMS orhealthcare system, and the patient’s condition.
  • 26. Endo Tracheal TubeThe endotracheal tube keeps the airway patent,permits suctioning of airway secretions,enables delivery of a high concentration of oxygen,provides an alternative route for the administration of some drugs,facilitates delivery of a selected tidal volume, and,with use of a cuff, may protect the airway from aspiration.Indications for emergency endotracheal intubation are(1) the inability of the provider to ventilate the unconscious patientadequately with a bag and mask and(2) the absence of airway protective reflexes (coma or cardiac arrest).The provider must have appropriate training and experience inendotracheal intubation.
  • 27. Endo Tracheal TubeDuring CPR providers should minimize the number and duration ofinterruptions in chest compressions, with a goal to limit interruptionsto no more than 10 seconds.Interruptions for endotracheal intubation can be minimized if theintubating provider is prepared.Compressions should be interrupted only for the time required by theintubating provider to visualize the vocal cords and insert the tube;this is ideally less than 10 seconds and be resumed as soon as tube ispassed the cords.If the initial intubation attempt is unsuccessful, a second attempt maybe reasonable, but early consideration should be given to using asupraglottic airway
  • 28. Endo Tracheal TubeIn retrospective studies, endotracheal intubation has been associatedwith a 6% to 25% incidence of unrecognized tube misplacement ordisplacement.Thus, even when the endotracheal tube is seen to pass through thevocal cords and tube position is verified by chest expansion andauscultation during positive-pressure ventilation, providers shouldobtain additional confirmation of placement using waveformcapnography or an exhaled CO2 or esophageal detector device(EDD).This may be due either to inadequateinitial training or lack of experience of theprovider who performed intubation, or thetube may have displaced when the patientwas moved.
  • 29. Endo Tracheal TubeThe provider should use both clinical assessment and confirmationdevices to verify tube placement immediately after insertion and againwhen the patient is moved.However, no single confirmation technique is completelyreliable, continuous waveform capnography is recommended inaddition to clinical assessment as the most reliable method ofconfirming and monitoring correct placement of an endotracheal tube.
  • 30. Endo Tracheal TubeClinical Assessment to Confirm Tube PlacementProviders should perform a thorough assessment of endotracheal tubeposition immediately after placement. This assessment should notrequire interruption of chest compressions.Assessment by physical examination consists of- Visualizing chest expansion bilaterally and- Listening over the epigastrium and the lung fields bilaterally.If there is doubt about correct tube placement, use the laryngoscope tovisualize the tube passing through the vocal cords. If still in doubt,remove the tube and provide bag-mask ventilation until the tube canbe replaced.
  • 31. Endo Tracheal TubeUse of Devices to Confirm Tube PlacementProviders should always use both clinical assessment and devices toconfirm endotracheal tube location immediately after placement andthroughout the resuscitation.Because of varying data over sensitivity and specificity of variousmodalities, all confirmation devices should be considered adjuncts toother confirmation techniques.
  • 32. Endo Tracheal TubeExhaled CO2 Detectors.Detection of exhaled CO2 is one of several independent methods ofconfirming endotracheal tube position.Studies of waveform capnography in victims of cardiac arrest have shown100% sensitivity and 100% specificity in identifying correct endotrachealtube placement, so it is considered the most reliable method to confirmproper placement of an ETT.Given the simplicity of colorimetric and nonwaveform exhaled CO2detectors, these methods can be used in addition to clinical assessment asthe initial method for confirming tube placement when waveformcapnography is not available.However, studies indicate that the accuracy of these devices do not exceedthat of auscultation and direct visualization for confirming the trachealposition of an endotracheal tube in victims of cardiac arrest.
  • 33. Endo Tracheal TubeEsophageal Detector Devices.The EDD consists of a compressed bulb attached to the ET tube. If the tubeis in the esophagus, the suction due to EDD will collapse the lumen ofesophagus and the bulb will not re-expand. Instead, a syringe may beattached to the ET tube; on attempting to pull the barrel of the syringe, itwont be possible to aspirate air, if the tube is in the esophagus.Studies indicate that the accuracy of these devices do not exceed that ofauscultation and direct visualization. Given the simplicity of the EDD, it canbe used as the initial method in addition to clinical assessment whenwaveform capnography is not available.The EDD may yield misleading results in patients with morbid obesity, latepregnancy, or status asthmaticus, or when there are copious endotrachealsecretions, because the trachea tends to collapse in the presence of theseconditions.
  • 34. Endo Tracheal TubeThoracic Impedance.Transthoracic impedance is slightly but significantly higher duringinspiration than during exhalation. Air is a poor electric conductor.Preliminary studies suggest that changes in thoracic impedance, as measuredthrough standard defibrillation pads, may distinguish tracheal fromesophageal intubations. There are 2 published reports involving 6 patientswhere ventilation-induced changes in thoracic impedance disappeared afteresophageal intubation.There is little evidence for the use of thoracic impedance in diagnosingadequacy of ventilation during CPR. Treatment decisions should not bebased solely on thoracic impedance measurements until further study hasconfirmed its utility and accuracy in this population.
  • 35. Postintubation Airway ManagementAfter inserting and confirming correct placement of an endotrachealtube, the provider should record the depth of the tube as marked at the frontteeth or gums and secure it.There is significant potential for endotracheal tube movement with headflexion and extension and when the patient is moved from one location toanother. Continuous monitoring of ET tube placement with waveformcapnography is recommended as discussed above.Devices and tape to secure the ET tube, should be applied in a manner thatavoids compression of the front and sides of the neck, which may impairvenous return from the tube, and other strategies provide equivalentmethods for preventing inadvertent tube displacement when compared withtraditional methods of securing the tube (tape).After tube confirmation and fixation, obtain a chest x-ray (when feasible) toconfirm that the end of the endotracheal tube is properly positioned abovethe carina.
  • 36. Ventilation After Advanced Airway PlacementIf monitoring of parameters other than rate during CPR improvessurvival is questionable.However, positive pressure ventilation may reduce venous return andcardiac output, especially in patients with hypovolemia or obstructiveairway disease.In animal models, slower ventilation rates (6 to 12 breaths per minute)are associated with improved hemodynamic parameters and short-termsurvival. Because cardiac output is lower than normal during cardiacarrest, the need for ventilation is reduced.Following placement of an advanced airway, the provider deliveringventilations should perform 1 breath every 6 to 8 seconds (8 to 10breaths per minute) without pausing in applying chest compressions(unless ventilation is inadequate when compressions are not paused)
  • 37. Automatic Transport VentilatorsIn both out-of-hospital and in-hospital settings, automatic transportventilators (ATVs) can be useful for ventilation of adult patients innoncardiac arrest who have an advanced airway in place.There are very few studies evaluating the use of ATVs attached toadvanced airways during ongoing resuscitative efforts.During prolonged resuscitative efforts the use of an ATV(pneumatically powered and time- or pressure-cycled) may allow theEMS team to perform other tasks while providing adequateventilation and oxygenationProviders should always have a bag-mask device available forbackup.
  • 38. Suction DevicesBoth portable and installed suction devices should be available forresuscitation emergencies.Portable units should provide adequate vacuum and flow for pharyngealsuction.The suction device should be fitted with largebore, nonkinking suctiontubing and semirigid pharyngeal tips.Several sterile suction catheters of various sizes should be available forsuctioning the lumen of the advanced airway, along with a nonbreakablecollection bottle and sterile water for cleaning tubes and catheters.The installed suction unit should be powerful enough to provide an airflowof 40 L/min at the end of the delivery tube and a vacuum of 300 mm Hgwhen the tube is clamped. The amount of suction should be adjustable foruse in children and intubated patients.
  • 39. SummaryAll basic and advanced healthcare providers should be able to provideventilation with a bag-mask device during CPR or when the patientdemonstrates cardiorespiratory compromise.Airway control with an advanced airway, which may include anendotracheal tube or a supraglottic airway device, is a fundamental ACLSskill.Prolonged interruptions in chest compressions should be avoided duringadvanced airway placement.All providers should be able to confirm and monitor correct placement ofadvanced airways; this key skill is required to ensure the safe and effectiveuse of these devices.Training, frequency of use, and monitoring of success and complications aremore important than the choice of a specific advanced airway device for useduring CPR.
  • 40. References1. Cardiovascular CareAssociation Guidelines for Cardiopulmonary Resuscitation and EmergencyPart 8: Adult Advanced Cardiovascular Life Support: 2010 American Heart.Circulation 2010;122;S729-S767Daniel Davis, Elizabeth Sinz and Laurie J. MorrisonScott M. Silvers, Rod S. Passman, Roger D. White, Erik P. Hess, Wanchun Tang,Robert W. Neumar, Charles W. Otto, Mark S. Link, Steven L. Kronick, MichaelMcNally, Shuster, Clifton W. Callaway, Peter J. Kudenchuk, Joseph P. Ornato, Bryan2. Miller’s Anesthesia.7th editionRonald D Miller3. Benumof’s Airway Management2nd editionCarin A Hagberg