EMT-Paramedic Notes: September 30, 2002
Airway Management
“A Neophytes Guide to Airway Management”
Hinderances To Oxygenation:
- Confined Space Rescue
- Low-Oxygen Enviornment
- Smoke-Filled Room
How To Restore Oxygenation (Step-By-Step):
- Oxygenate
- Ventilate via BVM
- Airway
- Upper
- Lower
- Airway
- Respiration (Chemical Process)
- Interfearances
- Pulminary Edema
- Carbon Monoxide
- Interfearances
- Circulation
- Pulminary Embolism (Blood Clot In Lungs)
- Celluar Respiration
- Off-Loading of Oxgen
- On-Loading of Carbon Dioxide
- Chemical(s):
- Cyanide (Partially-Burned Plastics)
Simple Diffusion:
(Balance of Gases, Controlled By pH; Carbon Dioxide is responsible for pH levels in the blood.)
Arterial - Off-Load Oxygen
Venous - On-Load Carbon Dioxide
Diffusion is affected by pH and temperature. Extremes of pH and temperature will hinder diffusion and may lead to death.
High CO2 = High Acidity
Low CO2 = Low Acidity
Faster and/or Deeper respirations remove excess CO2. Higher acidity makes picking-up oxygen more difficult. This will eventully lead to hypoxia.
ABG’s - Arterial Blood Gasses
Status Asthmaticus - Severe Asthma; Air goes in, but cannot come out.
Hinderances To Establishing An Airway:
- Confined Space
- Foregn Body Obstruction
- Confined Space
- Crushed Trachea
Secure An Airway Passage:
- Jaw Thrust
- Oral Airway
- Suctioning
- Intubation
- Respirations
Primary Objective: AIRWAY
- Major cause of precentable out-of-hospiral death.
- Most often neflected prehospital skill.
Functions of Upper Airway:
- Breathing through nose purifies the air; filtration, humidification, warming to body temperature.
- Cold can induse asthma.
- Oralpharynx
- Lips (Upper and Lower)
- Teeth (32 Usually)
- Tongue (The Single Biggest Obstruction To Your Success At Intubation)
- Muscle
- Attached To Ligaments
- Oral Airways ONLY Keep The Tongue Out Of The Way
- Glottis
- MRI studies have shown that this tissue blocks the airway more often than the tongue.
- Vallecula is located behind the eppiglottis. It closes the eppiglottis when food or liquid is swallowed.
- Hard Pallete
- Soft Pallete
- Uvula
- Pharynx
- Tonsil
- False Cords
- MRI studies have shown that this tissue blocks the airway more often than the tongue.
Blade Measurement:
- Straight Blade
- Measure blade from Adam’s Apple to lips.
- A blade too large can cause tissue injury and/or a false passage.
- Using the wrong size blade is your responsibility if harm is done.
- Curved Blade
- Measure from just above the Adam’s Apple to the lips.
- CPAP - Constant Positive Airway Pressure
- Used to treat sleep apnea.
- Instills air into lungs
Larynx:
- Thyroid Cartilage
- Glottic Opening
- Arytenoid Cartilage
ONCE YOU SEE THE GLOTTIC OPENING, YOU NEVER TAKE YOUR EYES OFF OF IT!
The “Gold Standard” of intubation is observing the tube passing through the vocal cords.
Lower Airway:
- Cricoid Ring
- Cricoid Ring
15% of drownings are “Dry Drownings” due to the fact that the vocal cords contract and may stay closed for a long duration of time.
Passive regurgitation requires 20 pounds of pressure on the cricoid membrane.
Anatomy of the Lower Airway
Located at about the 4th cervical vertibre, and is responsible for actual respiration (chemical).
Carina - The bifercation of the airway responsible for the division of the trachea into two seporate lungs.
The trachea is lined with cells that produce mucus. Cilia grows on the lining of the trachea and elevates the mucus. Smoking (Carbon Monoxide) may parylize the cilia; smokers are at an increased risk of bronchitis.
Autonomic Nervous System
Sympathetic
Parasympatheti c
Fight or Flight
- Dialatio n
- Epineffe rine Release
Feed and Breed
- Constriction
- Acetycholine Release
Beta 1:
Heart (”One Heart”)
Beta 2:
Lungs (”Two Lungs”)
Pediatric Airways
Balloon Cuffs are NOT used in Pediatric Intubations.
- Pharynx
- Tongue is Proportinally Larger
- Trachea
- Smaller
- Crichoid Ring is the Smallest Part of the Airway
- Funnell Shaped
- To About Age 10 (Based On Physical Development)
- Chest Wall
- Very Soft (Easy To Collapse)
- Sternal Collapse
- Resistance To Fracture
- Very Soft (Easy To Collapse)
ANY PEDIATRIC FRACTURE INDICATES AN EXCESSIVE AMOUNT OF FORCE INVOLVED TO CAUSE THE FRACTURE.
Lung / Respiratory Volumes:
- Total Lung Volume - 1:1 Ratio
- (Blood Liters) = (Air Liters)
- (10-15 CC) / (KG)
- Tidal Volume - Top 1/3 Of Lungs
- Approximately 500 CC
- Dead Air Space - 150 to 250 CC
- Anatomic Dead Space - Trachea, Lyrnx; Tubes where gas exchange does not occur.
- Physioloc Dead Space - Area of lungs where air sits.
Minute Volume:
- Tidal Volume - (Dead Air Space Volume) * (Respiratory Rate)
- Functional Reserve Capacity - How much you could possibly breathe in and then breath out.
- Asthma - Low Functional Reserve Capacities
- Residual Volume - What is left behind in lungs.
The primary drive to breath is based on blood acidosis. It is sensed in the aortic arch and corittod arteries.
Primary Drive - pH; Brain — Secondary Drive - Hypoxia; Brainstem
COPD Patients have high levels of Carbon Dioxide; these patients rely on hypoxic sensors to regulate respirations. Never withold supplemental oxygen.
Inhallation - Active — Exhallation - Passive
COPD or Asthmatic patients may sometimes use active exhallation intentionally to exhale air from their lungs.
97% to 98% of hemoglobin is bound together. As age increases, the bound hemoglobin may decrease to about 95%.
For every decade of life past 40 years of age, 10% of lung capacity is lost.
Respiratory Rate - The Number of Times You Breathe In One Minute
In times gone by, patients were placed into an iron lung machine to facilitate breathing. Today, a pacemaker-sized machine stimulates breathing.
Common Obstructions:
- FBAO (Foregn Body Airway Obstruction)
- Laryngospasm
- Fractured Larynx
Snoring Respirations indicate a partially-obstructed airway. Treatment is a jaw-thrust, which opens the airway.
Foregn Body Airway Obstructions may also be large objects stuck in the esophogus which directly puts pressure on the back of the trachea.
IM Injection of Glucogon will relax the esophogus and thus will stop the spasm in the esophogus. Ultimately the object will be “let go” by the esophogus and will pass by.
Liquids are aspirated more than solids. This is due to the fact that the opening to the trachea occurs at about a 90 degree angle. Therefore, nursing homes increase the risk of aspiration in their patients by serving liquified foods.
When the lyrnx goes into spasm, they may be difficult to open. Some stimulation may cause them to open. At last resort, the intubation tube may be forced through the cords. This in itself carries a high risk of irreversable complications.
Rule of thumb… It is better to assist breathing while they are still breathing and sitting up than to wait until they stop breathing and lie down to begin providing assistance.
Abnormal Respritory Patterns:
- Cheyenne-Stokes
- Kussmall’s
- Biots
- Central Neurogenic Hyperventilation
- Agonal
Increasing periods of apnea indicate that breathing is getting worse.
Oxygenation is supplemental; ventillation is more urgent than oxygenation.
An EMT should NOT wait to see cyanosis to begin oxygen administration. Cyanosis may be a late sign.
Any patient that shows signs of altered mental status is automatically assumed to be hypoxic until proven otherwise. It can be treated easilly, and supplemental oxygenation can do no harm.
Pulse Oxymeters MUST be calibrated at least anually and prior to being put into service.
Common O2 Tank Equations:
(PSI) * (0.28) = Volume
(Volume) / (LPM) = Duration in Minutes
Rule of 6’s: Never run a nasal cannula greater than 6 LPM, Never run a NRB Mask below 6 LPM.
Humidification with oxygen requires large-bore tubing. Typically 15 MM diamater is sufficient.
The Ease of Ventillation is called compliance. Harder ventillation may indicate a lost or compromised airway.
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