Cardiovascular Critical Care II
iv.
During chest compressions, air is forcefully expelled from the chest, and oxygen is drawn into
the chest by passive recoil. Because the ventilation requirements are lower than normal, passive
oxygen delivery is theorized to be sufficient for several minutes of initial CPR (Circulation
1994;90:3070-5), but recommendations to remove ventilation cannot be made.
Bag-mask ventilation: Viable option for oxygenation and ventilation during CPR but should be
provided only when there is more than one rescuer and/or trained personnel (for more details, see
earlier discussion) (Circulation 2010;122:S729-767).
| d. | Airway adjuncts |
|---|
Cricoid pressure should be used only in special circumstances to help visualize the vocal
cords and should be relaxed, released, or adjusted if it impedes ventilation or advanced airway
placement.
ii.
Oropharyngeal airways can be considered to help facilitate bag-mask ventilation in the
unresponsive patient with no cough or gag reflex.
iii.
Nasopharyngeal airways can be considered in patients with airway obstruction and clenched
jaw but should be used cautiously in craniofacial injury and avoided in known coagulopathy
because of an increased risk of bleeding (J Trauma 2000;49:967-8; Anaesthesia 1993;
48:575-80).
Advanced airways
Endotracheal intubation
| (a) | Attempted placement by unskilled providers leads to unacceptably large periods of chest |
|---|
compression interruption and hypoxemia.
| (b) | Benefits include keeping the airway patent, allowing for suctioning of airway, ensuring high |
|---|
oxygen concentration delivery, providing a third line medication administration option,
allowing for specific tidal volume delivery, and providing protection from aspiration.
ii.
Supraglottic airways
| (a) | Do not require visualization of glottis, which allow for continuous chest compressions. |
|---|---|
| (b) | Types studied during cardiac arrest include laryngeal mask airway, esophageal-tracheal |
tube (Combitube), laryngeal tube (laryngeal tube or King Airway LT), among others. No
difference in successful prehospital ventilation, ROSC, or 1-month neurologic outcome
between laryngeal mask airway and laryngeal tube for OHCA has been demonstrated (Am
J Emerg Med 2015;33:1360-3).
| (c) | When used by trained providers, they allow as effective oxygenation and ventilation as |
|---|
bag-mask ventilation and endotracheal intubation.
iii.
Recommendations regarding type of advanced airway are equivocal (Circulation
2019;140:e881-e894).
| (a) | Supraglottic airways can be used for adults with OHCA in settings with low tracheal |
|---|
intubation success rate or minimal training opportunities for ETT placement.
| (b) | Supraglottic airways or ETT can be used for adults with OHCA in settings with high |
|---|
tracheal intubation success rates or optimal training opportunities for ETT placement.
| (c) | If an advanced airway is used in the in-hospital setting by expert providers trained in these |
|---|
procedures, either the supraglottic airway or ETT can be used.
| (d) | Frequent experience/retraining is recommended for providers who perform endotracheal |
|---|
intubation.
| (e) | Emergency medical services systems that perform prehospital intubation should provide a |
|---|
program of ongoing quality improvement.
iv.
After advanced airways are secured, proper placement should be confirmed with clinical
assessment and objective measures without interruptions to chest compressions.