Interventions-Manual Ventilation Flashcards
The American Society for Testing and Materials (ASTM) and the International Standards Organization (ISO) recommend that manual resuscitators be capable of delivering a minimum fractional inspired oxygen of ________ with an oxygen flow of _____L/min.
0.85; 15
Little’s Area (Kiesselbach’s Plexus)
A highly vascular area located on the anterior aspect of the nasal septum in each nostril
Most nosebleeds will often originate from this area
Nasopharynx
In theory it is a passage for air alone
Extends from the base of the skull to the uvula
Contains pharyngeal tonsils (adenoids) and tubal tonsils
5 Openings to Nasopharynx
The nasopharynx contains 5 openings which is important during intubation as we can have infection
These openings are
- 2 eustachian tubes
- 2 Internal nares
- 1 opening to the oropharynx
Oropharynx
Extends from tip of uvula to upper rim of the epiglottis
Common pathway for food and air
Contains palatine tonsils, which are commonly removed during tonsillectomy
Larynx
Conducts air into the lungs
Acts a switch mechanism to ensure that food bypasses the trachea and proceeds down the esophagus
Larynx is the most heavily sensory inervated organ in the body.
Stimulation of unaesthetized larynx causes very strong sympathetic response-HR and BP may double.
Cartilage of the Larynx
There is 9 Cartilages of the Larynx
- 2 Arytenoid Cartilages
- 2 Cuneiform Cartilages
- 2 Corniculate Cartilages
- 1 Thyroid Cartilage
- 1 Cricoid Cartilage
- 1 Epiglottis Cartilage
Trachea
When we are intubating we want to go into the trachea we have to manipulate things because if we don’t manipulate things then the path of least resistance for intubation is through the esophagus
If doing an emergency cricoid cartilage you don’t have to go through the cric you can go through a ring that is not continuous but C shaped
Thyroid Cartilage
Thryroid cartilage forms anterior wall of larynx
Trachea Measurements
Extends from the larynx to the main stem bronchi
12-15 cm in length
~2 cm in diameter
16-20 C-shaped cartilage rings
Carina Topography
Carina sits behind “angle of Louis” anteriorly and level of T4 posteriorly
Loss of Airway Patency
Causes of loss of airway patency can be divided into 2 general categories
Central Causes-Any condition that leads to a depression of the CNS (i.e. <8)
Peripheral Causes-Airway obstruction caused by something originating outside the body
Central Causes of Loss of Airway Patency
When the CNS is depressed and comes from within the body
The causes of CNS depression varies
Most common cause of upper airway obstruction is the tongue
Includes-Decrease in cardiac output, TBI, Anesthesia, drug overdose, hypoxemia/hypercarbia, hypothermia/hyperthermia, metbolic derrangements
Central Causes
Decrease in Cardiac Output
Acute myocardial infarction (MI)
Cardiac tamponade-But when cause through a infection it is considered to be a peripheral cause
CHF
V fib or V tach
Hypovolemic Shock
Septic Shock
Massive Pulmonary Embolism
Mechanisms of Upper Airway Obstruction
Decrease in tone of submandibular muscles leads to posterior displacement of tongue against the posterior pharyngeal wall
While in a comatose state the position of the chin will worsen the obstruction
C-spine adopts a semi flexed position, narrowing the distance between the tongue and posterior pharyngeal wall
Epiglottis gravitates towards the larynx partially occluding the airway
Negative pressure cause by respiratory efforts in presence of obstruction draws tongue towards the airway
Peripheral Causes
- Peripheral causes come from outside of the body
- Infection
- Abscess
- Neoplastic (carcinomas)
- Physical and Chemical Agents
- Thermal
- Caustic Injuries- Can cause swelling
- Inhaled toxins
- Allergic/Idiopathic
- Traumatic
Signs of Loss of Airway Patency
• Tachypnea and dyspnea • Noisy snoring respirations • Paradoxical breathing • Tracheal tug or retractions • Nasal flaring o Usually seen in babies • Expiratory Grunting o Is a compensation for collapse o Usually seen in babies o Cardiac dysrhythmias • Pressure in chest and low oxygen levels will affect the heart • Stridor • Absence of breath sounds or visible chest movement • Cyanosis o Can be misleading due to polycythemia or hypothermia o Will be check at the inside of the lips
Peripheral Causes-Infection
Viral and bacterial infection laryngotracheobronchitis (e.g. croup)
Parapharyngeal and retropharyngeal abscess
Lingual tonsillitis
Hematomas or abscess of the tongue or floor of the mouth
Epiglottitis (also known as supraglottitis)
Similar to croup but the patient will have low energy and is very serious and in this case we do not manipulate the airway
Peripheral Causes-Neoplastic
Laryngeal carcinomas Hypopharyngeal and lingual (tongue) carcinomas
Peripheral Causes-Physical and Chemical Agents
Foreign bodies Chocking something shoved up a nose Thermal injuries-Can cause swelling Caustic Injuries- Can cause swelling Inhaled toxins
Peripheral Causes- Allergic/Idiopathic
Angiotensin converting enzymes inhibitors induced angioedema
Peripheral Causes- Traumatic
Blunt and penetrating neck and upper airway trauma
Central Causes-Hypoxemia/Hypercarbia
COPD, Asthma, ARDS, Pneumonia, moderate PEs
Central Causes-Metabolic Derangements
Hypo/hyperglycemia
hypo/hypernatremia
hypokalemia (lead to heart malfunction)
metabolic acidosis
hepatic encephalopathy