initial management of critical airway and breathing emergencies

Initial Management of Critical Airway and Breathing

Emergencies

Does he need to be intubated? If yes, when and how?

How would you manage this patient?

58 y/o in shock and respiratory failure

Four airway questions

• Is the airway open?

• Is breathing adequate?

• Is oxygenation adequate?

• Is the airway protected?

Indications for intubation

Do these patients need to be intubated?

• Failure to maintain and/or protect airway

• Failure to oxygenate and ventilate

• Facilitate therapy or diagnostic procedures

When to do the intubation?

When to intubate?

• Now?• Within 10 minutes?• Within 30 minutes?• Almost all patients can be managed initially

with good BVM ventilation– proper equipment– good technique– airway adjuncts

What is the safest and best method to intubate?

• Rapid Sequence Intubation

• Awake intubation techniques– Blind nasotracheal intubation– Awake oral intubation– Fiber optic guided intubation– Retrograde intubation over a catheter

• Surgical technique

Rapid Sequence Intubation (RSI)

Simultaneous administration of a potent sedative (anesthetic) and a

neuromuscular blocking agent to facilitate endotracheal intubation

History of emergency airway management

• Most ER intubations performed on unresponsive patients

• Sedation without paralytics

• C-spine concerns in trauma

• Blind nasotracheal vs. RSI in the ED

Rapid Sequence Intubation

“the method of choice for emergency airway management in most patients”

RK Knopp: Ann Emerg Med 1998

Rapid Sequence Intubation - 9 Ps

1. Preparation

2. Preoxygenate

3. Premedicate

4. Push sedative (Anesthetic)

5. Paralyze

6. Position airway: head/neck position; laryngeal manipulation, BURP, cricoid pressure as needed

7. Pass the tube (intubate)

8. Patent airway assessment

9. Post-intubation plan

RSI: Timing• Five minutes before intubation: Preparation including

selection of drugs & doses, equipment check and team roles; preoxygenation; premedication.

• 45 - 60 seconds before intubation: administer sedative and paralytic, start laryngeal manipulation 45 - 60 seconds after drugs, introduce laryngoscope, intubate and immediately prove tracheal intubation.

This is the Rapid Sequence!• Intubate + 1 minute: Post intubation care

Preparation

• Check equipment– Laryngoscopes, ET tubes,

suction, introducer– Back up airway

• Attach monitors - cardiac, oximetry

• Establish IV (prefer 2), gather drugs

• Assign tasks to team members

Preparation

• Airway drugs– Draw up drugs– Label syringes– Use ET Flow sheet

Shamrock Dispenser

Preoxygenate

100% O2 by mask for 3-5 mins

or

3 - 4 vital capacity breaths

Undesirable responses to intubation

• Increases ICP

• Bronchospasm

• Bradycardia in children

• Hypertension/tachycardia

• Fasciculation's with Succinylcholine

Pretreatment: attenuation of physiologic response to intubation

• Lidocaine– May block increase in ICP– May attenuate bronchospasm

• Atropine– Blocks vagal response in children

• Opioids (Fentanyl)– Blocks cardiovascular response

• Non-depolarizer– Blocks fasciculation

RSI Drugs - pretreatment• Lidocaine - head injury,

asthma (1.5 mg/kg)

• Atropine - children <8 (0.02 mg/kg)

• Fentanyl - 1-2 micrograms/kg

RSI Drugs - sedation

• Etomidate (Amidate)

• Thiopental

• Midazolam (Versed)

• Ketamine

• Propofol (Diprivan)

Etomidate (Amidate)

Dose: 0.3mg/kgOnset: 30-60 secondsDuration: 3-5 minutesAdvantages: Short acting, lowers ICP,

with no adverse cardiovascular effects,

Disadvantages: Nausea, myoclonus, ? Cortisol suppression

Ultrashort-acting nonbarbiturate hypnotic

Etomidate and septic shockcurrent (2010) controversy

• Etomidate known to suppress cortisol secretion• Ability to mount a cortisol response is thought to

be important to outcome in septic shock• No studies to date clearly link Etomidate and

increased mortality in septic shock• Recommended approach:

– Use another sedative?– Supplemental steroids if Etomidate used?– Draw cortisol level and give steroids if low?

Midazolam (Versed)Short acting benzodiazepine

Dose: 0.1-0.3 mg/kg (larger dose /kg in kids; 10 mg usual max single dose for adults)

Onset: 30-60 seconds

Duration: 30-80 minutes

Cautions: Reduces SVR, myocardial depressant

Ketamine

Dose: 1-2 mg/kg IV, may give 4mg/kg IM

Advantages: Bronchodilator as well as anesthetic; induction agent of

choice in asthma.

Disadvantages: Emergence reactions in adults (age > 15), increases ICP so

contraindicated in head injury

*For most RSI - other sedatives are preferable

RSI Drugs – neuromuscular blockers (paralytics)

• Depolarizing NMBA– Succinylcholine

• Non-depolarizing NMBA– Vecuronium (Norcuron)– Rocuronium (Zemuron)

SuccinylcholineUltra short-acting depolarizing neuromuscular blocker

Dose: 2.0 mg/kg IV

Onset: 45-60 seconds

Duration: 4-6 minutes

Precautions: Burns or crush injuries greater than one week, increased intraocular pressure, hyperkalemia

Succinylcholine-induced hyperkalemic cardiac arrest

• Acetylcholine Receptor Up-regulation– Extensive burns, extensive muscle trauma (crush

injuries)– Denervation: spinal cord injury, stroke, Guillain-

Barre– Extensive atrophy or prolonged immobilization

• Myopathic Processes– Muscular dystrophy– Rare Idiopathic

Granert, Anesthesiology. March 2001

K+ = 8

Rocuronium (Zemuron)Competitive nondepolarizing agent

Dose: 0.6 – 1.0 mg/kg IV

Onset: 70 seconds

Duration: 30 minutes

Indications: When Succinylcholine is contraindicated, post-intubation paralysis

Vecuronium (Norcuron)Competitive non-depolarizing agent

Dose: 0.1 mg/kg IV

Onset: 2-3 minutes

Duration: 45 minutes

Indications: When succinylcholine is contraindicated, post-intubation paralysis

Whatever drugs and equipment you decide to use, always use a written reference or at least a calculator for drug doses, volumes and equipment

needs

The rapid sequence

• Push sedative• Push paralytic• Position airway ( Sellick's maneuver may be

used)• Wait 45 seconds• Do not ventilate unless the patient is hypoxic• Laryngoscope and pass the tube• Check the tube

Pass the tube (intubate)

• Wait 45-60 seconds after Succinylcholine

• Position airway after Succinylcholine

• Maintain in-line cervical immobilization in patients with suspected C-spine injury

Laryngoscopy

• Laryngeal anatomy (epiglottis, glottis, aryepiglottic folds, posterior cartilages, interarytenoid notch, vocal cords)

• Patient positioning, mouth opening, tongue• Blade selection / light source• Laryngeal manipulation / cricoid pressure• Stylet shaping, ET tube railroading• Pediatric, obese

Laryngoscopy practice

• Training videos• Laryngoscopy courses• Operating room opportunities• Discuss cases with colleagues

• In studies, ED & OR intubation success rates increased from 40-90+% with training

Practice will improve first pass success!

Failed airway

• Always be prepared for a failed airway• First try to ventilate, then try again

– Bag/valve/mask, Combitube/King tube, LMA

• If able to ventilate, try another technique– Fiberoptic intubation– Retrograde intubation– Use of bougie

• Unable to intubate or ventilate, then surgical airway

Patent airway assessment

• This is done immediately after intubation

• CO2 detection with capnography or colorimetric device

• Suction device (esp. in cardiac arrest)

• Breath sounds, oximetry and X-ray confirm proper placement

Post intubation management

• Secure tube

• Chest X-ray

• Continued SEDATION (Midazolam 0.1 mg/kg)

and PARALYSIS (Vecuronium 0.15 mg/kg )

• Maintain cervical spine immobilization

• Pass OG tube

Post-intubation management II

• Be aware of malignant hyperthermia: rare but lethal• Check temperature at least once 15 -30 minutes after

intubation and/or before transfer

• Watch for muscular rigidity especially masseter spasm, unexplained tachycardia, labile BP, increased End tidal CO2 and increased temperature

• If suspected, follow CALS protocol and notify anesthesia/critical care/referral center

Anticipate the difficult airway

• Severe facial trauma

• Penetrating or blunt neck trauma

• Laryngeal edema or inhalation injuries

• Short neck, receding mandible

• Prominent upper incisors

• Limited mouth opening

• Limited ability to extend at atlanto-occipital joint

Mallampati airway classification

How would you handle this airway?

Management of Difficult Airway

Tracheal tube introducer

Blind nasotracheal intubation

• Requires breathing, somewhat cooperative patient• Anesthetize the airway with 4% Lidocaine and 1/2%

Neo-synephrine• Mild sedation• Use standard ET tube without the stylet• Pass tube gradually listening for increasing breath

sounds• Pass tube through cords on inspiration

Awake oral intubation

• Requires breathing, somewhat cooperative patient• Anesthetize the airway with 4% Lidocaine and 1/2%

Neo-synephrine• Conscious sedation with Midazolam and Fentanyl• Perform gentle laryngoscopy to attempt to visualize

the cords• May then give neuromuscular blocker• If cords are seen, may attempt to pass the tube at

that time or perform RSI

Case: Head injury

9 y/o fell off bicycle, hit head on large rock. Unconscious at scene.

On arrival he was semi-conscious, moaning, and withdrawing to any painful stimulation. GCS = 10.

BP 100/60, HR 102, R 16, SpO2 100% on 10 LPM by NRB mask. Lungs clear with good air movement. Pupils - 3 mm, reactive. Motor exam - withdraws all extremities symmetrically.

Does he need to be intubated? If yes, when and how?

Head injury - 9 yr old

Preoxygenate: 100% O2

Pretreatment: Lidocaine 1.5 mg/kgAtropine 0.02 mg/kg

Sedation: Etomidate 0.3 mg/kg

Paralytic: Succinylcholine 2 mg/kg

Post intubation: Versed 0.1 mg/kg Vecuronium 0.15 mg/kg

Case: Asthma

5 y/o child with a history of asthma presents with severe difficulty breathing. On arrival she is only able to gasp out one word at a time. She appears mildly cyanotic on room air.

BP 120/60, HR 160, R 30. O2 started with Albuterol neb. IV established. ABGs pending. She becomes obtunded with decreasing respiratory effort.

How would you manage this patient?

Asthma: 5 yr old

Preoxygenate: 100% O2

Pretreatment: Lidocaine 1.5 mg/kg, Atropine 0.02 mg/kg

Sedation: Ketamine 1 - 2 mg/kgVersed 0.1 mg/kg

Paralytic: Succinylcholine 2.0 mg/kg

Post intubation:Versed 0.1 mg/kg Vecuronium 0.15 mg/kg

58 y/o in shock and respiratory failure

Nebulize: 4% Lidocaine, 0.5% phenylephrine

Insert endotracheal tube into nose

Successful awake intubation

Summary

• Most patients can and should be managed initially by good basic airway techniques

• Many critically ill or injured patients will benefit from intubation

• Intubation may be accomplished by several different techniques: RSI, blind nasal tracheal, cricothyrotomy, etc.– Always a planned procedure– Always a foolproof rescue plan