Airway and Ventilation Management in the Trauma Patient.
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Transcript of Airway and Ventilation Management in the Trauma Patient.
Airway and Ventilation
Management in the Trauma Patient
Airway / Ventilation of the Trauma Patient : Objectives
ƒ Recognize acute airway obstructionƒ Be familiar with airway management
techniques–Airway opening maneuvers–Orotracheal & nasotracheal intubation–Needle cricothyroidostomy / jet ventilation–Alternative difficult airway techniques–Surgical cricothyroidostomy
ƒ Be familiar with devices for oxygen administration and ventilation–Masks, bag-valve-mask, mechanical ventilators
Importance of Airway Management
ƒ Airway obstruction is the most rapid killer of the trauma patient
ƒ Airway management is always the first step in trauma management
Risk Factors for Airway Obstruction in the Trauma Patient
ƒ Decreased mental status–Head injury–Effects of alcohol or drugs
ƒ Facial fracturesƒ Blunt neck traumaƒ Burns / smoke inhalation
And in some : congenital airway structural abnormalities
Specific Causes of Airway Obstruction
ƒ Head position : slumped forward
ƒ Blood ƒ Vomitusƒ Foreign bodyƒ Extrinsic compression
–Neck hematomas–Neck abscesses
ƒ Airway wall edema
Signs of Airway Obstruction(Should Note These "From Across the Room")
ƒ Unconsciousƒ Unable to speakƒ Retractions
–Sternal, intercostal, subcostal
ƒ Poor or abstract air movementƒ Cyanotic or grey skin colorƒ "Noisy" or "gurgly" breathingƒ Stridor
Airway Management Precautions
ƒ If the patient may have a neck injury : always maintain neck immobilization during airway management
ƒ Avoid distraction of the neck
Best neck immobilization with towel, collar, and hands
Airway Opening Maneuvers
ƒ Head tilt / neck lift –Do not do if possible neck injury
ƒ Chin liftƒ Jaw thrustƒ Suction oropharynx &
nasopharynxƒ Remove oropharyngeal foreign
bodies with Magill forcepsƒ Always start oxygen concurrent
with airway maneuvers
Chin lift and head tilt maneuvers
Head tilt and neck lift
Initial Airway Adjuncts(act to hold open the upper airway)
ƒ Oropharyngeal airway–Do not use if patient conscious (will cause gagging & vomiting)
ƒ Nasopharyngeal airway–Do not use if mid-face fracture (may go through fracture site and penetrate brain)–Relatively contraindicated if severe coagulopathy (may stir up bleeding) and in children (may cause bleeding from enlarged adenoids)
Oropharyngeal airways (note how 2 can be hooked together to do mouth to tube ventilation)
Use the distance from the corner of the mouth to the ear to select the correct size oral airway
Actually a better insertion method is to insert the airway at a 90 degree angle and then rotate it into position over the tongue
Use of a tongue depressor to help insert an oral airway
Don’t allow this to happen !
Standard red rubber nasopharyngeal airways
Proper position of the inserted nasal airway
These protect the rescuer by allowing mouth to device ventilation rather than mouth to mouth
Other types of barrier ventilation masks
An oxygen reservoir is required in order to give the patient oxygen concentrations greater than 60 %
Another type of bag-valve with oxygen reservoir (the black corrugated tubing)
Correct hand position for one person ventilation
Two person bag-valve-mask ventilation (can achieve bigger ventilation volumes than by one person)
Patients in Whom a Definitive Airway Is Needed
ƒ Depressed mental statusƒ Protect from aspiration of blood or
vomitusƒ Head injury requiring hyperventilationƒ Patient requires sedation or anesthesia
to obtain computed tomography scanƒ Emergency surgeryƒ Major chest wall injuryƒ Respiratory failureƒ Anticipated prolonged ventilation
Advantages of Endotracheal Intubation
ƒ Protects the airway from aspirationƒ Facilitates ventilation & oxygenationƒ Enables direct suctioning of secretions
from tracheaƒ Provides route for administration of
resuscitative medicationsƒ Prevents gastric inflation from
ventilationsƒ Maintains airway against edema or
compression
Orotracheal Versus Nasotracheal Intubation
ƒ Orotracheal preferred–Patient apneic–Midfacial fractures–Known coagulopathy
ƒ Nasotracheal preferred–Patient breathing–Short / thick neck–Status epilepticus
ƒ Either method okay for patients with suspected neck injury as long as neck immobilization maintained (nasotracheal can cause higher incidence of delayed sinusitis)
Preparation for Endotracheal Intubation
ƒ Have suction ready and operating–Yankauer (large bore) catheter–Flexible catheter
ƒ Choose endotracheal tube (ETT) size–Have 2 "adjacent" sizes also available
ƒ Have stylet and syringe ready (use of stylet to stiffen the ETT is routinely recommended for both adults & children)
ƒ Check equipment–Test bulb on laryngoscope, test inflate balloon on ETT
ƒ Have bag-valve-mask (BVM) ready and attached to oxygen flow
ƒ Have medications labeled and readyƒ Have stethescope ready
Suction canisters and tubing must be ready before intubation
Ideal patient positioning for intubation (assuming neck injury is not present)
Extra sheets and pillows may be needed for ideal airway positioning for a very obese patient
Choice of Laryngoscope Blades
ƒ Straight blade (such as Miller) used to directly lift the epiglottis–May be best if "floppy" epiglottis suspected (which is more common in children)
ƒ Curved blade (such as Macintosh) used to indirectly expose the glottic inlet by lifting up from the vallecula
ƒ Should have both available since unpredictably sometimes one works better than the other for some patients
Intubation equipment to have ready
Routine use of a stylet is recommended for intubation of both adults and children
You need to align the axes of the mouth, pharynx, and trachea for intubation to be successful ; these axes are not aligned when the neck is flexed
Good alignment of the mouth, pharynx, and tracheal axes for intubation
Also called the Sellick maneuver
Place the laryngoscope in the mouth and sweep the tongue to the left
Correct placement of straight blade
Correct placement of curved blade
Laryngoscopic view with the straight blade (left) and the curved blade (right)
Laryngoscopic views with different blades
Insert the endotracheal tube from the right (do not place it directly down the channel of the laryngoscope blade or it will obstruct your view)
Correct endotracheal tube positioning using a curved blade
Precautions About Endotracheal Intubation
ƒ Do not attempt if the patient is not adequately sedated
ƒ Before using ANY of the sedatives or paralytic agents, personnel MUST know well the pharmacology of these agents
ƒ If personnel are not skilled in intubation, continued ventilation by bag-valve-mask is preferable to a botched intubation attempt
General Guidelines for Endotracheal Intubation
ƒ If needed, it should be done as early as possible in the resuscitation
ƒ It should be attempted by the most experienced person present
ƒ No more than 30 seconds per attempt should be taken; the patient should be reventilated with BVM after each 30 seconds
Use of Medications for Assisted Intubation ("Rapid Sequence Intubation")*
ƒ If the patient is completely unconscious and unresponsive, medication use to assist in intubation (except perhaps IV lidocaine) is usually unnecessary
ƒ Complications are reduced by proper use of sedation and paralytic agents*This really should be called "Medication-Assisted-
Intubation" because if done properly, it is not actually "rapid"
Potential Complications of Endotracheal Intubation
ƒ Esophageal intubation : causes death if unrecognized
ƒ Mainstrem bronchus intubation : can result in collapse of other lung
ƒ Pneumothoraxƒ Oropharyngeal bleedingƒ Vocal cord injuryƒ Fractured teeth ; tooth fragments could be
aspiratedƒ Vomiting & aspirationƒ Movement of an unstable cervical spine injury
"Classic" Sequence of Medications to Use for Assisted Intubation ("Rapid Sequence Intubation")
ƒ Oxygen : preoxygenate the patient (VERY important)
ƒ Lidocaine : 1 to 1.5 mg/ Kg IV (to blunt the increase in ICP from intubation; efficacy of this is debated)
ƒ Pancuronium or vecuronium 0.01 mg/ Kg IV (usually one mg; to prevent fasciculations from succinylcholine)
ƒ Diazepam or Midazolam 0.1 to 0.7 mg/ Kg IV (usually 5 mg)
ƒ Succinylcholine 1 to 1.5 mg/ Kg IVƒ Cricoid pressure (Sellick maneuver) to prevent
aspirationƒ Intubate (Pass the ETT)Note : Usually wait 2 minutes in between each
medication to allow it time to take effect
Contraindications to Succinylcholine
ƒ Known hyperkalemia (as in renal failure patients)
ƒ Burns (if delayed time from injury)ƒ Muscular dystrophy / other muscle diseasesƒ Major crush injuries (if delayed time from
injury)ƒ Family history of Malignant Hyperthermia
or pseudocholinesterase deficiencyRemember that succinylcholine may not be needed (thereby avoiding the rare chance it will cause hyperkalemia or hyperthermia) if the patient is so sick that they already have very relaxed muscle tone
Considerations About Use of Paralytic Agents for Endotracheal Intubation
ƒ DO NOT USE if not able to ventilate the patient with a bag-valve mask in case the intubation fails
ƒ Succinylcholine has rapid onset (30 to 60 seconds) and relatively short duration (unless patient has pseudocholinesterase deficiency) of 10 to 15 minutes
ƒ The nondepolarizing agents have slower onset and more prolonged half life–Use of "priming dose of 0.5 to 1 mg IV 3 minutes before main dose may shorten onset to 60 seconds
Other Medication Options for Medication-Assisted Intubation
ƒ Etomidate 0.3 mg / kg IV–Causes rapid brief sedation & apnea–If repeated can cause adrenal suppression–Usually causes no cardiovascular complications
ƒ Ketamine 2 mg / kg IV or 4 mg / kg IM–Older studies indicated it may cause increased intracranial & intraocular pressures, but this is debated–Can rarely cause laryngospasm & "emergence reactions" (agitation after awakening)–Usually minimal effects on cardiorespiratory status
More Medication Options for Medication-Assisted Intubation
ƒ Barbiturates (used as "induction" agent)–All commonly cause hypotension & apnea
ƒ Methohexital 1 to 3 mg / kg IVƒ Thiopental 3 to 5 mg / kg IVƒ Propofol 2 to 2.5 mg / kg IV (can be continuous infusion)
ƒ Narcotics–Also can cause hypotension & apnea & histamine release (but can reverse with naloxone 0.4 to 2 mg IV)
ƒ Morphine 0.01 to 0.1 mg / kg (often 2 mg initial dose)
ƒ Fentanyl 3 to 50 micrograms / kg (can rarely cause muscle & chest wall rigidity if high dose given rapidly)
Options for Nondepolarizing Neuromuscular Blockers (Paralytics)
Name Dosage (IV) Comments
Atracurium 0.4 to 0.5 mg/kg useful in renal failure
Cis-atracurium 0.1 to 0.2 mg/kg
Pancuronium 0.1 mg/kg can cause cardiac side effects
Rocuronium 0.6 to 1.2 mg/kg faster onset
Vecuronium 0.1 mg/kg useful for pro- longed paralysis
Additional Medication Considerations for Endotracheal Intubationƒ If a paralytic agent is used, a sedative or
induction agent MUST be also used (it is inhumane to chemically paralyze someone without making them unaware of the paralysis)–Benzodiazepines are useful for this because even in small doses they cause brief retrograde amnesia
ƒ They also may blunt the "emergence reactions" from ketamine, and can be reversed with Flumazenil 0.2 mg IV
ƒ In children < 8 years, atropine 0.01 mg/kg (minimum 0.1 mg) is recommended to prevent vagal reactions from succinylcholine (& the succinylcholine dose is 2 mg/kg)
More Considerations About Medication - Assisted Endotracheal Intubation
ƒ For inexperienced personnel, the safest agents to use are probably the benzodiazepines and narcotics (because they can be reversed), and etomidate or ketamine
ƒ Post - intubation paralytic agents are needed for patients who are combative from head trauma or intoxication–If possible and safe, a complete neurologic exam should be completed prior to use of extended paralytic agents
Sequence of Events for Intubation
ƒ Prepare equipmentƒ Preoxygenateƒ Administer medications; Sellick maneuver (cricoid
pressure)ƒ Pass the tube & inflate cuff balloonƒ Release Sellick maneuverƒ Ventilateƒ Listen with stethescope over both sides of chest
and upper abdomenƒ Use end-tidal CO2 detector if availableƒ Secure the tube with tape (record depth number at
lips ; usually 21 to 23 cm in adults)ƒ Obtain chest X-ray to check tube position
An X-ray you don’t want to see : Esophageal intubation
A qualitative colorimetric end tidal CO2 detector
(use helps recognize possible esophageal intubation)
Use of a GU syringe as an esophageal intubation detector
Use of a bulb syringe as an esophageal intubation detector
How to tape secure an oral endotracheal tube
Securing an oral endotracheal tube (using also an oral airway keeps the patient from biting on the endotracheal tube)
How to tape secure a nasotracheal tube
Indications for Surgical Airway (Cricothyroidotomy)
ƒ Inability to orotracheally or nasotracheally intubate and airway control required–Failure or impossibility of "backup" intubation methods
ƒ Upper airway obstruction (above level of vocal cords)
"Backup" Alternative Endotracheal Intubation Techniques
ƒ Should have a "Difficult Airway " cart with this extra airway equipment available in the E.D.–Combitube
ƒ Can be inserted blindlyƒ Often helpful in controlling oropharyngeal bleeding
–Trach-Liteƒ Also a "blind" technique
–Retrograde intubation over a guide wireƒ Uses a central intravenous line kit
–Commercial percutaneous tracheostomy insertion sets
The Combitube is a good “backup” alternative airway technique
Combitube in the esophageal position (about 85 % of the time when inserted it will be in the esophagus)
Combitube in the tracheal position (note ventilation bag is now attached to the other lumen)
Another type of “blind” insertion airway : the pharyngotracheal lumen airway (PTL)
Another “backup” technique: placing an endotracheal tube down the lumen of the intubating LMA (laryngeal mask airway)
Technique for Retrograde Intubation Over a Guide Wire
ƒ Puncture cricothyroid membrane with needle aimed proximally, then pass central intravenous line guide wire thru the needle into the pharynx
ƒ Look into the pharynx and pull the guide wire with a Magill forceps so it exits from the mouth
ƒ Cut off the proximal thicker portion of a nasogastric tube and insert the lubricated tube over the wire to the predetermined depth equivalent to the distance from the mouth to the cricoid puncture site
ƒ Insert an endotracheal tube over the nasogastric tube
ƒ Pull the wire and nasogastric tube out of the mouthƒ Advance the endotracheal tube a little farther
Needle Cricothyroidostomy : Technique
ƒ Prep neck with iodine or alcohol if time allowsƒ Insert 14 gauge needle thru cricothyroid
membrane (or use IV catheter over needle & withdraw needle)
ƒ Attach stopcock and oxygen tubingƒ Run oxygen in for one second ; open stopcock
for 3 to 4 seconds & keep repeating this cycleƒ Can instead attach 3 cc syringe barrel & then
attach ETT connector & ventilate with BVM directly
ƒ Prepare for surgical cricothyroidostomy if possible (to establish larger diameter airway)
High pressure tubing required for jet ventilation for a needle cricothyroidostomy
Technique of verifying entry into the trachea with a catheter over needle
Setup for direct ventilation of a needle cricothyroidostomy
Direct bag valve ventilation to a needle cricothyroidostomy
Surgical Cricothyroidostomy : Technique
ƒ Prep front of neck if time allowsƒ Incise skin & cricothyroid membrane
horizontallyƒ Insert tracheostomy tube or 6.0 or 6.5
mm. diameter endotracheal tube & inflate cuff balloon
ƒ Ventilate thru tubeƒ Auscultate over chest and abdomenƒ Secure tube with tape or straps around
neckƒ Chest X-ray to check tube position
Surgical cricothyroidostomy
Minimum instruments needed for surgical cricothyroidostomy
Emergency tracheostomy
One of several available types of percutaneous cricothyroidostomy tubes
Choosing Endotracheal Tube Size (Inner Diameter in mm.)
ƒ Small adults : 7.0, 7.5ƒ Large adults : 8.0, 8.5, 9.0ƒ Children :
–Can use formula 16 + age in years divided by 4–Or use tube with diameter same as child's little finger
ƒ For nasotracheal intubation, choose tube 0.5 to 1 mm. diameter smaller than for oral
Reassessment of the Intubated Patientƒ Reauscultate to check tube position
after each time the patient is movedƒ Note printed number on the tube at the
level of the lips & record in chartƒ Continuous pulse oximetry if availableƒ Consider hand restraints if patient
combative or likely to awaken and attempt to pull tube
ƒ Suction the ETT frequentlyƒ Recheck pressure in cuff balloon every
6 to 8 hours (should be < 25 mm Hg)
Technique of Tracheobronchial Suctioning
ƒ Set suction pressure between 80 to 120 mm Hg
ƒ Preoxygenate with 100 % oxygen for 3 to 5 minutes
ƒ Use sterile technique (gloves)ƒ Insert suction catheter thru tubeƒ Apply suction & pull out catheter with a
rotary motionƒ Limit suction to no more than 10 seconds
per attempt
Oxygen Concentrations Deliverable from Airway Adjuncts
Device O2 Concentration
Nasal cannula (2 to 6 l/min)
24 to 44 %
Face mask (6 to 10 l/min)
40 to 60 %
Face mask with O2 Reservoir
60 to 98 %
Venturi mask 28 to 40 % by selected increments
Airway Management Summary
ƒ Airway management is always first priority
ƒ Always maintain cervical spine precautions
ƒ Decide early if definitive airway needed
ƒ Complete preparations before attempting to intubate
ƒ Reassess the intubated patient frequently
Specific Airway Skills : Practice Session
ƒ Airway opening maneuversƒ Placement of airway adjuncts (oral & nasal
airways)ƒ Adult orotracheal intubationƒ Adult nasotracheal intubationƒ Pediatric orotracheal intubationƒ "Backup" alternative intubation techniquesƒ Needle cricothyroidostomyƒ Use of bag-valve-mask (perhaps the most
important skill)