Airway Management

Review

Airway management

Giedrius Laurinėnas

Airway management

A look back: what's learnt from bitter experience Future trends: a vision of a 'universal soldier' Lithuania: Go west

Airway management

A look back: what's learnt from bitter experience • Difficult airway is an interdisciplinary problem • The diagnostics wasn't, isn't, and, apparently, Future trends: a vision of a won't be accurate 'universal soldier' • Updated knowledge, vigilance, adequate monitoring and standardization is the key for success: - Standards of Safe Anesthesia Practice (ASA, 1986) - Difficult Airway Algorithm (ASA, 1993) Lithuania: • Alternative airway devices revolutionized outcomes Go westfor a proper education • Ever growing interest

The Problem

Adverse respiratory events in anesthesia: A closed claims analysis. Caplan RA, Posner KL, Ward RJ Anesthesiology 75:828, 1990 ••• N = 1541 infrequently leading Adverse respiratory events Inadequate ventilation 13% to malpractice suits. A closed claims analysis. Cheney FW, Posner KL, CaplanEsophageal RA Other claims Anesthesiology 75:932, 1991intubation 7% •••

34%

Difficult intubation 6%

ASA closed claims project database Other respiratory problems 8% 1985-2004

The Problem

Adverse respiratory events in anesthesia: A N = 4459 closed claims analysis. Caplan RA, Posner KL, Inadequate Ward RJ Anesthesiology 75:828,ventilation 1990 7% •••

18%

Esophageal intubation 4.5%

Other claimsrespiratory events infrequently leading Adverse to malpractice suits. A closed claimsDifficult analysis. intubation 6,4% Cheney FW, Posner KL, Caplan RA Anesthesiology 75:932, 1991 •••

ASA closed claims project database 2002

The Problem

Anesthesia-related deaths and permanent brain damage (ASA closed claims project database, 2002)

N= 1320 1980-1990

N= 570

Respiratory adverse events Cardiovascular adverse events Technical problems

1990-2000

A look back

Monitoring: The Beginning of A New Era

A look back Monitoring modalities and respiratory adverse events (ASA closed claims project database)

Inadequate ventilation

Esophageal intubation

Difficult intubation

Both SaO2 and EtCO2 unavailable SaO2 monitoring only SaO2 ir EtCO2 available Mirtys ir CNS pakenkimas dėl anestezijos (ASA closed claims project database, 2004)

Monitoring of Ventilation ... Continuous evaluation of qualitative clinical signs such as chest excursion, observation of the breathing bag, and auscultation is mandatory... ... When an ETT or LMA is inserted, its correct positioning must be verified by identification of carbon dioxide in the expired gas. Continuous capnometry should be used until extubation... ... Quantitative monitoring of the volume of expired gas is strongly encouraged...

ASA Standards for basic Anesthetic Monitoring

Ventilation monitoring • Exploring Lithuania • 9 OR fully equipped with capnography....................................10% 9 Hospitals without capnography............................................12% 9 Hospitals, where blood gas analysis is unavailable.................0%

F Capnometry in our operating rooms: 9 District hospitals..................................................................42% 9 Regional nonteaching hospitals.............................................55% 9 University hospitals..............................................................70%

F Capnometry in our ICUs: 9 ICUs, where capnography is used at least from time to time......8%

F Capnometry in our prehospital setting: 9 Ambulances equipped with capnometry devices..............not found

Ventilation monitoring • Kokybiniai etCO2 detektoriai • Recent advances •

2000 Qualitative end-tidal CO2 detectors

American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care

Esophageal detectors

Ventilation monitoring • Recent advances •

2004 ? Microstream capnometry Day case surgery

Sleep apnea monitoring Extended cardiovascular uses of capnography (CPR, electromechanic dissociation ...) Pulmonology

Ventilation monitoring • Other uses of capnometry •

One lung ventilation

Fiberoptic bronchoscopy

spontaneous breathing

apnea

Needle cricothyrotomy

Critical care

Monitoring of Oxygenation ... Adequate illumination and exposure of the patient are necessary to assess color...

... During all anesthetics, pulse oximetry shall be employed...

... The concentration of oxygen in the breathing system shall be measured with a low FiO2 alarm in use... ASA Standards for basic Anesthetic Monitoring

Oxygenation monitoring • Exploring Lithuania • 9 Hospitals, fully equipped with pulse oximetry.........................4% 9 Hospitals, where pulse oximetry is unavailable.......................0%

F Pulse oximetry in operating rooms: 9 District hospitals...................................................................59% 9 Regional nonteaching hospitals..............................................46% 9 University hospitals...............................................................73%

F Pulse oximetry in ICUs: 9 District hospitals...................................................................57% 9 Regional nonteaching hospitals..............................................51% 9 University hospitals...............................................................60%

F Pulse oximetry in the prehospital setting: 9 Ambulances, equipped with pulse oximeters.............a recent victory

Equipment Status Monitoring ... There shall be in continuous use a device that is capable of detecting disconnection of components of the breathing system ...

... Anesthesia apparatus check-up is an essential part of any anesthesia ...

... Unreliable and unsecure anesthesia equipment should not be used ...

Equipment status monitoring • Obsolescence criteria • • Necessary and approved replacement parts are impossible to obtain

It's the responsibility of the • Evident leakage in the breathing system ASA Guidelines anesthesiologist to determine • Absent oxygen supply alarm, no FiO detector • Absent automatic O ratio device, no "fail-safe" system forO /NDetermining if a machine’s failure to meet • Absent airway pressure (P-peak, PEEP, negative pressure) alarm* Anesthesia Machine newer equipment standards • Impractical equipment (e.g.,, no possibility to utilize other vaporizers or to perform a low flow anesthesia)* a threat to patient Obsolescence • Arepresents significant possibility of human error due to tremendous technological differencies when compared with modern anesthesia machines* safety (...) • No standard connections

2

2

* Relative criteria

2

Anesthesia equipment • Exploring Lithuania •

F Stationary anesthesia machines in the OR: 9 District hospitals...................................................................85% 9 Regional nonteaching hospitals..............................................89% 9 University hospitals...............................................................89%

F Newer (<5 years) anesthesia machines: 9 District hospitals...................................................................16% 9 Regional nonteaching hospitals..............................................16% 9 University hospitals................................................................9%

F Older (>10 years) anesthesia machines: 9 District hospitals....................................................................31% 9 Regional nonteaching hospitals...............................................25% 9 University hospitals................................................................13%

Ventilation equipment • Exploring Lithuania •

F Provision with ventilators of our ICUs: 9 District hospitals...................................................................48% 9 Regional nonteaching hospitals..............................................49% 9 University hospitals...............................................................59%

F Newer (<5 years) ventilators in ICU: 9 District hospitals...................................................................26% 9 Regional nonteaching hospitals..............................................21% 9 University hospitals...............................................................40%

F Older (> 10 years) ventilators in ICU: 9 District hospitals...................................................................53% 9 Regional nonteaching hospitals..............................................17% 9 University hospitals...............................................................10%

A look back

Deaths and brain damage related to difficult airway (ASA closed claims project database, 2003)

100

50

0

Desperate attempts of intubation only

Alternative airway devices used

A look back

Searching for a perfect one

A

ABCD (Airway)

Alternative airway management devices • Laryngoscopes •

Blades

Handles

McCoy laryngoscope

Alternative airway management devices • Laryngoscopes •

Flexiblade

Bullard laryngoscope

Wu scope

Upsher laryngoscope

Alternative airway management devices • Intubation adjuncts •

Flexible stylets

Guminis elastinis bužas

Gum elastic bougie

Lighted stylets

ETT with controllable tip

Alternative airway management devices • Supraglotic devices •

Nasopharyngeal airway

Oropharyngeal airway

COPA (cuffed oropharyngeal airway)

Esophageal obturator airway

Alternative airway management devices • Supraglotic devices •

Laryngeal mask airway (LMA)

Intubation LMA (Fastrach)

Laryngeal tube

Combitube

Alternative airway management devices • Infraglotic devices •

Transtracheal jet ventilation

Cricothyrotomy

Tracheostomy

Translaryngeal tracheostomy

B

ABCD (Breathing)

Ventilation devices • Primary survey •

Faceshield (Microshield)

Pocket face mask

Ventilation devices • Advanced •

Bag-valve device

Demand valve

Ventilation via Combitube

Ventilation via LMA

Emergency transport ventilator

ICU ventilators

Searching for an ideal one • What should I choose? • EXPERIENCE • It's the main factor influencing one's decision. Many alternative techniques, however, could be relatively easily learnt. • Intubation is still considered a "gold standard". One should maintain acceptable intubation skills. SITUATION • Factors to consider: aspiration risk, possible ventilation difficulties, risks associated with patient transportation • LMA and Combitube are effective when one needs to establish airway patency quickly, in nonstandard position or in case of difficult intubation SURGICAL INTERVENTION • LMA is the best known alternative airway device in elective as well as in emergency anesthesiology • Endotracheal intubation is preferred during prolonged procedures, in case of nonstandard positioning of the patient PATIENT • The indications of alternative devices in airway management is only partly defined. There are, however, well-established contraindications. • Only few specific recommendations for suspected cervical spine injury, presence of dangerous infections have been developed

Prehospital setting • What should I choose? •

The manner in which a patient's airway is maintained often influences how effectively ventilation and transportation is accomplished

Prehospital setting Despite constantly increasing selection of alternatives, an ideal airway device for prehospital airway does not yet exist Difficult intubations are more common in prehospital circumstancies. Poor intubation experience, errors in tube position diagnostics and lack of monitoring are detrimental

Oxygenation and effective ventilation are the main priorities

Prehospital setting • Exploring Lithuania •

F Anesthesiologists in prehospital setting

it's a minority F Fully equipped ambulances ('reanimobiles')

usually up to 100 km away F Alternative airway devices available 9 Combitube..............................................................................rarity 9 Laryngeal mask...........................................................................no 9 Succinylcholine............................................................................no

Prehospital setting • Endotracheal intubation issues • FAILED PREHOSPITAL INTUBATIONS: AN ANALYSIS OF EMERGENCY DEPARTMENT COURSES AND OUTCOMES Henry E. Wang et al, Prehospital Emergency Care 2001;5:134–141

592 prehospital intubations ••• AN ANALYSIS OF INVASIVE AIRWAY MANAGEMENT IN A SUBURBAN EMERGENCY MEDICAL SERVICES SYSTEM Prehosp Disaster Med 1992; 7:121-126

278 prehospital intubations

Prehospital setting • Endotracheal intubation issues •

• Knowledge of indications for endotracheal intubation is of paramount importance • The incidence of difficult intubation subsides remarkably if muscle relaxants are used. Although rare, potential complications could be lethal. A great deal of experience is required when using these pharmacological adjuncts. • There is still no clearly defined and internationally supported indications for their use in prehospital setting • Intubation with iv sedation seems to be a reasonable choice • There is no clear consensus on the number of intubations required to train prehospital personnel adequately and maintain their skills. A figure of approximately 10 per year is often cited.

Prehospital setting • Ventilation priorities • AHA Guidelines 2000 for cardiopulmonary resuscitation and emergency cardiac care

Emergency and transport ventilators

Demand valve

Pocket face mask

Bag - mask ventilation

Prehospital setting • Ventilation priorities • AHA Guidelines 2000 for cardiopulmonary resuscitation and emergency cardiac care

Combitube + bag-mask

Laringinė kaukė + bag-mask

Bag-mask only

Combitube An ideal option for our ambulances?

Prehospital setting • Combitube • Use of the Esophageal Tracheal Combitube by basic emergency medical technicians. Resuscitation 2002 Jan;52(1):77-83)

760 prehospital insertions of Combitube • insertion successful 95,4% • ventilation successful 91,4% • sucutaneous emphysema (18) • tension pneumothorax (5) • pharyngeal bleeding (15) • airway edema (3)

No Combitube related injuries established at autopsy

Combitube Indications

Advantages

• Difficult intubation (especially useful in case of bleeding from upper airways and gastrointestinal tract or profuse vomiting as well)

• No experience is required

• Quick establishment of airway is needed (especially useful in prehospital setting) • Elective surgery, especially in case of deformities of neck and face. Also recommended for actors and singers

• No 'sniffing' position is needed • No preparation is needed Combitube is ready for immediate use • Suitable in case of 'full stomac'. Minimal aspiration risk if inserted correctly • Fixation is unnecessary

Contraindications

Disadvantages

• Conscious patient or the presence of gag reflex

• Requires ablation of consciousness

• Small (<1.52 m) adults

• Its insertion can evoke cardiovascular reactions

• Children (up to sixteen years old) ? • Corrosive injuries of gastrointestinal tract • Foreign bodies • Tracheostomy • Esophageal abnormalities

• Serious complications (esophageal trauma, subcutaneous emphysema, pneumomediastinum etc) • Difficulties if bronchoscopy is needed

Prehospital setting • Combitube • Complications associated with the use of the EsophagealTracheal Combitube. Vezina D et al. Can J Anaesth 1998

1139 prehospital insertions of Combitube 8 Combitube-related subcutaneous emphysema 4 Combitube-related esophageal lacerations

Combitube Where is the tip? Bag ventilation via blue port

Chest rises, breath sounds are present, no gurgitation

Chest does not rise, gurgitation in epigastrium is heard

Ventilation via blue port Gastric tube via white port Drugs via blue port?

Ventilation via white port Observe, listen, look Drugs via white port

• Always use capnography, esophageal detectors or end-tidal carbon dioxide detectors. Recheck position during transportation • Do not overfill the distal cuff • Consider endotracheal intubation

Unable to ventilate via either port, no sounds heard

Deflate cuffs Withdraw 2-3 cm Reinflate Recheck If situation does not changes, reinsert Combitube once more. If unsuccessful, consider other airway devices

Prehospital setting • Combitube • Comparison of a conventional tracheal airway with the Combitube in an urban emergency medical services system run by physicians. Rabitsch W et al. Resuscitation, 2003;57(1):27

172 prehospital airway emergencies A: Endotracheal intubation • Successful 94% • Failed 6%

B: Combitube insertion • 98% successful • 2% failed

Combitube and endotracheal intubation could act as a substitute of each other. Intubation success rate increases, if these devices are used concomitantly

Prehospital setting • Combitube vs LMA • • So far, there are no well-controlled, randomized, prospective studies • Success rates for insertion of both the Combitube and the LMA depend on adequate initial training and frequent practice. Those that were trained in the OR had much higher success rates for insertion of the LMA A choice of airway device for 12,020 cases of nontraumatic cardiac arrest in Japan. Tanigawa K et al. Prehosp Emerg Care 1998. Overall successful insertion and ventilation rates Combitube 73.5% vs 64% LMA Both of these devices provide good options for airway rescue in the event of failed intubation, but in prehospital studies neither have consistently high success rates for insertion and ventilation

Hospital setting Hospital: An underused source of knowledge and experience for the prehospital care staff Despite better equipment, monitoring, and extensive experience of hospital staff, perioperative respiratory adverse events are still common Noncompliance with standardized action plan as well as the absence of preplanned strategy in case of difficulties seems to be the main problem

Hospital setting • Suggested portable storage unit (ASA, 2003) •

Alternative laryngoscope blade (McCoy, Miller, Bullard) Endotracheal tubes of assorted sizes Tracheal tube guides (semirigid stylets, tube changer, lighted stylet, Magill forceps) Laryngeal mask airway of assorted sizes and types Flexible fiberoptic intubation equipment Retrograde intubation equipment Noninvasive ventilation devices (Combitube, hollow jet ventilation stylet, transtracheal jet ventilation) Emergency invasive airway access (cricothyrotomy equipment) Exhaled carbon dioxide detectors

Hospital setting • Exploring Lithuania •

F Availability of a portable kit for difficult airways

0% F Hospitals equipped with all required devices

0% F Hospitals without any alternative device 9 District hospitals....................................................................63% 9 Regional nonteaching hospitals...............................................33% 9 University hospitals................................................................12%

Hospital setting • Exploring Lithuania •

F Most common alternative airway devices: 9 Laryngeal mask...............................................24% 9 Cricothyroidotomy kit.....................................18% 9 Fiberoptic bronchoscope.................................18% 9 Combitube.........................................................8% 9 Rigid bronchoscope...........................................8% 9 Alternative blades of laryngoscopes.................5% 9 COPA..................................................................4% 9 Intubating LMA..................................................2%

Laryngeal mask The essential tool

LMA Currently available items

Classical LMA

Dual-lumen LMA

Disposable LMA

Wire - reinforced LMA

Intubating LMA

LMA accessoires

Laryngeal mask ADVANTAGES

Easy insertion technique Multifunctional device (a ventilatory device or conduit for tracheal intubation) Placement success is not influenced by anatomic abnormalities A first choice device in case intubation has failed Minimal cardiovascular response after insertion 'Smooth' awakening Minor vocal cord dysfunction Well tollerated in awake patients Reusable DISADVANTAGES

Risk of aspiration Risk of gastric distention Risk of dislodgement Isn't suitable in case of any gross laryngeal abnormality Drug administration via LMA is a bit problematic

LMA performs adequately even when it is used poorly. Try it!

LMA Failed insertion

0,4-6%

LMA Failed insertion

Insufficient deflation

Excessive deflation

Wrong pressure direction

Entrapped epiglottis

Folded mask

Wrong LMA size

LMA The role of LMA in case of difficult airway ....Chadwick IS et al. Anaesthesia for emergency caesarean section using the brain laryngeal airway (letter). Anaesthesia 1989. McClune S et al. Laryngeal mask airway for caesarean section. Anaesthesia 1990. Priscu V et al. Laryngeal mask for failed intubation in emergency caesarean section (letter). Can J Anaesth 1992; De Mello WF et al. The laryngeal mask in failed intubation (letter). Anaesthesia 1990 Storey J et al. The laryngeal mask for failed intubation at caesarean section (letter). Anaesth Intensive Care 1992; Williams AR et al. The laryngeal mask airway-suboptimal availability, a cause for concern (letter). Anaesthesia 1992. Denny NM et al. Laryngeal mask airway for emergency tracheostomy in a neonate (letter). Anaesthesia 1990. Wheatley RS et al Intubation of a one-day old baby with the pierre-robin syndrome via a laryngeal mask (letter). Anaesthesia 1994; Myles PS, Venema HR, Lindholm DE: Trauma patient managed with the laryngeal mask airway and percutaneous tracheostomy after failed intubation (letter). Med J Australia 1994. Brain AIJ: The laryngeal mask airway--a possible new solution to airway problems in the emergency situation. Arch Emer Med 1984; Brain AIJ: Three cases of difficult intubation overcome by the laryngeal mask airway. Anaesthesia 1985; Calder I, Ordman AJ, Jackowski A, Crockard HA: The brain laryngeal mask airway: An alternative to emergency tracheal intubation. Anaesthesia 1990; Lim W, Wareham C, de Mellow WF, Kocan M: The laryngeal mask in failed intubation (letter). Anaesthesia 1990; Owen G, Browning S, Davies CA, Saunders M, Thomas TA: The laryngeal mask (letter). BE Med J 1993; Gature PS, Hughes JA: The laryngeal mask airway in obstetrical anaesthesia. Canadian J of Anaesth 1995....

An endless evidence in all age groups

Difficult Airway Algorithms • In the world •

Universal algorithm (ASA, 1993 - 2004)

National algorithm

(Italy, France etc)

National database

(Austria)

Difficult Airway Clinic

(Michigan, USA, 1987)

Local algorithm

Difficult Airway Algorithm • Exploring Lithuania •

F Approved algorithms for difficult airway: 9 Local hospitals......................................................................43% 9 Regional nonteaching hospitals..............................................50% 9 University hospitals...............................................................83%

F Algorithms adopted: 9 ASA 'Difficult Airway Algorithm (1993-2004)...........................10% 9 Local algorithms...................................................................38% 9 Algorithms are under development..........................................2% 9 No algorithm available..........................................................50%

Difficult airway algorithms Most of difficult intubations could be foreseen

Awake airway management is a mainstay of all difficult airway algorithms

Oxygenation is the highest priority

Difficult airway algorithms Established indications and priority range for alternative airway devices

Portable unit for difficult airway is highly recommended

A difficult intubation should be communicated to the patient. Appropriate records are made as well.

Difficult Airway Algorithm • Incidence •

• Official statistics is contradictory 9 0,5-20% depending on type of surgery, skills and facilities 9 3rd degree laryngoscopy 0,05% (1:2000) 9 4th degree laryngoskopy < 0,05% 9 Failed intubation -? 9 Failed mask ventilation - ? 9 Cannot ventilate, cannot intubate 0,01% (1:10000)

• Unofficial statistics: 15-30% 9 90% of cases are preventable with more careful airway status assessment

Difficult Airway Algorithm • Problem 1: Poor sensitivity •

Lingual tonsil hyperplasia: an unexpected catastrophe

Difficult Airway Algorithm • Problem 2: Nonstandardized technique • Effects of posture, phonation and observer on Mallampati classification. Tham EJ et al. Br J Anaesthesia, 1992

Difficult Airway Algorithm • Problem 3: Predictors of difficult mask ventilation ? • Definition • Air leak is evident • No chest rise • SaO2 < 90% when ventilating with 100% O2

• Necessity to increase flow up to 15 l/ min or to use a by-pass button more than twice • Persistent hypoventilatrion • Necessity to constantly change patient's positioning

Incidence • 0,07 % El-Ganzouri AR. Anesth Analg 1996 • 0,9 % Rose DK. Can J Anaesth 1994 • 1,4 % Asai T. Br J Anaesth 1998 • 5 % Francon D. AFAR 97, Langeron O. Anesthesiology 2000 • 15 %

Williamson JA. Anaesth Intens Care 1993

Predictors • Deformities, burns, scars, trauma

• Obesity

• Beard

• Snoring

• Absence of teeth

• Advanced age • Obstructive sleep apnea

Difficult Airway Algorithm • Problem 3: Predictors of difficult mask ventilation •

Difficult ventilation predicts difficult intubation ••• Ventilation is more complex in difficult intubations

Difficult Airway Algorithm • Everybody is involved •

Patient's drama Circumstancies Anesthesiologist's drama

Expected difficult airway

A look back

Anesthesia-related deaths and brain damage (ASA closed claims project database, 2004)

100

50

0

Unexpected difficult airway

Expected difficult airway

Expected difficult airway • General considerations • • An informed consent is mandatory • Awake intubation techniques are employed. Sedation monitoring is highly recommended (Ramsay 3) • Techniques: FOB, intubation in local anesthesia, retrograde witre intubation. A new alternative: intubating LMA, Bullard laryngoscope • Uncooperative patient is a great problem. FOB is relatively contraindicated, elective surgical airway seems to be a reasonable choice • Risky: regional anesthesia, mask anesthesia without any back-up plan in case the necessity of intubation ensues • Not recommended: classical LMA, blind intubation through the LMA, FOB in general anesthesia • If failed: 9consider re-preparation of the patient for awake intubation or cancel case 9use different blades, LMA as a FOB conduit, retrograde intubation, face mask and other anesthesia methods 9surgical airway (elective or emergency)

Expected difficult airway ASA Difficult Airway Algorithm Difficult airway Expected in an uncooperative patient

Expected

Unexpected

Induction of general anesthesia Proper preparation Awake intubation

Failed intubation Call for help. Ventilation via face mask

Failed

Ventilation ineffective

Ventilation effective Alternative noninvasive approaches (bronchoscopy, retrograde intubation...)

LMA LMA failure

As a As a definitive ventiliation temporary ventiliation device device

Combitube Noninvasive and surgical airway access techniques

A conduit for fiberoptic intubation

Flexible fiberoptic intubation

Bronchoscopy • Exploring Lithuania •

F Availability of fiberoptic bronchoscopes 9 Local hospitals......................................................................10% 9 Regional nonteaching hospitals..............................................64% 9 University hospitals...............................................................75%

F If available, FOB service is provided by 9 Anesthesiologists....................................................................47% 9 Other physicians....................................................................35% 9 Nobody is experienced in FOB................................................18%

F Rigid bronchoscopy 9 Availability.............................................................................8% 9 Nevertheless, nobody is experienced in rigid bronchoscopy.....50%

Fiberoptic intubation Indications

• Expected difficult intubation • Unexpected difficult intubation in a non hypoxic patient • Airway obstruction (foreign bodies, neoplasm..) • Unstable or immobile cervical spine • Endobronchial intubation

Contraindications and drawbacks

• Uncooperative patient • Hypoxia • Obscure view anticipated (incontrollable secretions etc) • Profuse bleeding if uncontrollable with active suctioning

• Airway hygiene

• Hypersensitivity to local anesthetics (for an awake patient)

• Tracheostomy (percutaneous, surgical)

•Inexperience of the operator

• Aspiration

Flexible fiberoptic intubation The most common problems • Toxicity of local anesthetics • Complications of oxygen insufflation • Absence of any back-up plan in case of failure / complications • No alternative airway device available • Hang-up (inability to pass an ETT through the vocal cords) • ETT placed too deep • Lost landmarks due to inexperience • Obstructing base of tongue or epiglottis • Reflex closure of the glottis, bronchospasm, vomiting, severe cardiovascular reaction • Inadequate sedation of the awake patient • Hypersecretion, epistaxis • Fogging of the FOB

Retrograde wire intubation An underused alternative

Retrograde wire intubation Indications

Contraindications and drawbacks

• An alternative to FOB in case of expected difficult airway

• A hypoxic patient

• Poor visualization of anatomic structures (blood, hypersecretion, deformities etc) in a nonhypoxic patient

• Difficulties in identifying the cricothyroid (obesity, neck trauma and tumors etc) • Laryngotracheal stenosis • Disorders of bleeding • Infection

Complications • Hoarseness (14) • Bleeding (11) • Subcutaneous emphysema, pneumomediastinum, pneumothorax (6) • Esophageal trauma • N. trigeminus injury (1)

Retrograde wire intubation

Possible ways: a small ETT-over-a guidewire, a guidewire-through- Murphy Eye, a guidewire-through-a FOB Important notes • A local anesthesia of the trachea, nasal and oral cavity is recommended, if time allows • The needle is advanced over the mid-cricothyroid membrane at an angle of 45° to the chest while maintaining neck extension • J - shaped introducer is at least 2,5 times the length of a standard ETT (typically 1,1-1,2m) • Coughing typically heralds caudad travelling of the wire • Obstruction is usually overcome if the position of head and neck is changed

Unexpected difficult airway

Unexpected difficult airway • Priorities • • Oxygenation is the first priority. Reevaluate the oxygenation status before any subsequent attemp. Ventilation status should be constantly surveyed as well. • If mask ventilation becomes inadequate, the aspiration issues are not considered • It's highly recommended to refer to Cormack-Lehane laryngoscopy scale. • Persistent attempts of intubation are detrimental. Three attempts are usually allowed, but try once in case of the most difficult laryngoscopy grade • LMA and Combitube is the first choice devices if ventilation becomes ineffective. Do not defer the insertion of LMA. Later, it will be of little value due to progressive posttraumatic edema. If failed, consider transtracheal oxygenation. • FOB should be immediately available. It is used when the patient awakes. • Blind intubation through the LMA and blind nasal intubation is no longer recommended

Unexpected difficult airway ASA Difficult Airway Algorithm Difficult airway Expected in an uncooperative patient

Expected

Induction of general anesthesia

Awaken Proper preparation Awake intubation Cancel case

Failed intubation Call for help. Ventilation via face mask

Postpone case Failed

Ventilation ineffective

Ventilation effective Alternative noninvasive approaches (bronchoscopy, retrograde intubation...)

LMA LMA failure

Unexpected

LMA as LMA as a definitive ventiliation temporary ventiliation device device

Combitube Noninvasive and surgical airway access techniques

A conduit for fiberoptic bronchoscope

Intubating laryngeal mask

Intubating LMA Its role in the management of difficult airway

Use of the Intubating LMAFastrach™ in 254 Patients with Difficult-to-manage Airways Anesthesiology, 2001

The overall success rates for blind and fiberoptically guided intubations through the LMA-Fastrach™at three attempts were

96,5 - 100%

Intubating LMA Advantages • One of the most effective airway devices in case of difficult intubation and/or extubation • Hypersecretion, blood, edema usually do not influence the success rate • Positioning of physician is an unimportant issue • One hand remains free • Safe in case of suspected unstable cervical spine (no 'sniffing' position is needed) • No contact with a dangerous infection • Accomodation of large-lumen ETT (8,0 mm) • Very suitable for bronchoscopy

Disadvantages • Special endotracheal tubes are needed for intubation • Complicated ILMA removal • No suitable for prolonged procedures • Possibility of trauma and dislodgement if patient's position is changed • Contraindicated in case of pharyngolaryngeal abnormalities • Possible difficulties if mouth opening is reduced

Intubating LMA The place of LMA in ASA Difficult Airway Algorithm Difficult airway Expected in an uncooperative patient

Expected

Unexpected

Induction of general anesthesia Proper preparation Awake intubation

Failed intubation Call for help. Ventilation via face mask

Failed

Ventilation ineffective

Ventilation effective Alternative noninvasive approaches (bronchoscopy, retrograde intubation...)

Intubating LMA LMA failure

LMA as LMA as a definitive ventiliation temporary ventiliation device device

Combitube Noninvasive and surgical airway access techniques

ILMA as a conduite for FOBi

The Last Chance

Difficult Airway Algorithm • Cannot intubate, cannot ventilate •

• Consider LMA, Combitube, rigid bronchoscope. If failed, percutaneous cricothyrotomy is the procedure of choice. • Decision to do it should not be delayed or postponed. Most physicians hesitate at potentialy grave risk to the patient • Tracheostomy is never an emergency procedure. If indicated (eg., a laryngeal neoplasm-related obstruction), it is performed electively using a local anesthesia • Every anesthesiologist should be familiar with basic transtracheal oxygenation techniques. Practicing on mannequins is shown to be effective and therefore it's strongly recommended

Cannot ventilate, cannot intubate 1. Percutaneous cricothyroidotomy 1. If difficult intubation is expected, potential puncture site should be identified, dressed and anesthetized 2. The right-handed clinician stands on the right side of patient, the trachea is fixated with nondominant hand. 3. Needle is advanced at right angle in the caudad third of the membrane. Constant aspiration is applied until the trachea is entered.

• Large - bore (3.5-6 mm) access Ventilation and oxygenation with low-pressure system is adequate. A 1-1,5 cm vertical skin incision is needed. Insertion direction is 45° caudad. A Seldinger technique may be used to pass a dilator with the catheter

Cannot ventilate, cannot intubate 1. Percutaneous cricothyroidotomy

• Low pressure system Ambu bag or anesthesia circuit is used. This cannot provide enough flow to expand the chest adequately, but it's a temporary oxygenation mean while a more definitive airway is secured. • High pressure system Jet ventiliator or "O2 flush" is used. Vt 400-700 ml is achievable via a 16G catheter. Insufflations 1-1,5 sec every 5 sec. Mouths and nose closure is often needed during insufflation (but not exhalation)

Cannot ventilate, cannot intubate 2. Surgical emergency airway access

• Complication rate is 20-40% higher when compared to transtracheal jet ventilation • Reported complications: laryngeal stenosis, voice changes (10-15%), bleeding (up to 8%), tube misplacement

Cannot ventilate, cannot intubate 3. Teaching problem Comparison of Cricothyrotomy Methods Performed by Inexperienced Clinicians. Eisenburger et al. Anesthesiology, March 2000

40 first-time cricothyroidotomies Surgical cricothyrotomy

vs

Successful placement 60%

Successful placement 70% Failure due to subcutaneous, paratracheal and esophageal tube placement

Seldinger technique

.

Failure due to kinking of guidewire

Cannot ventilate, cannot intubate 3. Teaching problem What Is the Minimum Training Required for Successful Cricothyroidotomy?: A Study in Mannequins. Wong DT et al. Anesthesiology, 2003

102 anesthesiologists performing cricothyroidotomies on mannequins

. By the fifth attempt, 96% of participants were able to successfully perform the cricothyroidotomy in 40 s or less

Difficult Airway The problem of teaching

Training Guidelines in Anaesthesia of the European Board of Anaesthesiology, Reanimation and Intensive Care (2001) • For most manual skills, a necessary number of cases per procedure has been determined to achieve an optimal rate of success. As concernes difficult airway situations, no prospective study has established the minimum number of training sessions required. • Nevertheless, European Academy of Anesthesiology strongly suggests the use of anesthesia simulators and mannequins during the training process. • Prehospital and emergency medicine is an important advance in contemporaneous residency training program.

Teaching airway skills • Exploring Lithuania •

Survey of sixteen ex-residents (2001-2004)

Teaching airway skills • Exploring Lithuania •

F Experience of difficult intubation with a compromised oxygenation

94% It must have been a preventable disaster in....... 53%

F What guides you in case of difficulties? 9 Local algorithm of difficul intubation....................................14% 9 My own experience.............................................................20% 9 ASA Difficult Airway Algorithm ............................................66%

Teaching airway skills • Exploring Lithuania •

F Airway techniques performed 9 LMA..........................................................................................100% 9 Endobronchial intubation..............................................................87% 9 Awake intubation........................................................................75% 9 Nasal intubation..........................................................................69% 9 Modified laryngoscopes (McCoy, Miller etc)...................................56% 9 Tracheostomy.............................................................................50% 9 Combitube..................................................................................13% 9 Fiberoptic intubation....................................................................13% 9 Retrograde wire intubation (incl. on a mannequin)..........................6% 9 Cricothyrotomy (incl. on a mannequin)...........................................6% 9 Lighted stylet (incl. on a mannequin)..............................................6% 9 Gum elastic bougie or similar device...............................................0%

Teaching airway skills • Exploring Lithuania •

F Evident lack of experience 9 Fiberoptic intubation.............................................................100%

9 Gum elastic bougie and other stylets.......................................87% 9 Nasal intubation.....................................................................69% 9 Modified laryngoscopes (McCoy, Miller blades etc)....................44% 9 Awake intubation...................................................................19% 9 LMA......................................................................................13% 9 Combitube.............................................................................13%

F Gaps in the residency program 9 Fiberoptic intubation..............................................................100%

9 Alternative airway devices.......................................................87% 9 Simmulators and mannequins..................................................50%

Difficult Airway Room for improvement

• Better knowledge of an appropriate plan / algorithm • Being prepared to perform awake intubation more often • More practice in fiberoptic intubation • Always having an appropriate sized LMA immediately available • All anesthesiologists knowing, and practicing on mannequins, how to oxygenate via the cricothyroid membrane • All anesthesiologists knowing that a difficult intubation should be communicated to the patient

Teaching airway skills • Exploring Lithuania •

2003

2004

Teaching airway skills • Exploring Lithuania •

2005 A Year of Airway Management ?

2003

2004

The Happy End