PulmCrit – Beware of the Risk of ETT Exchange
Highlights
- Risks of ETT exchange (1) Airway loss due to inability to replace the ETT. There’s no guarantee that a fresh ETT will pass into the trachea. Occasionally the fresh ETT may get hung up on the glottis (this usually responds to gentle 90-degree rotation of the ETT, but not always!). If you are unable to pass the ETT, this may cause a huge problem – especially if you aren't properly prepared with all your airway equipment at the bedside. (2) Laryngeal trauma. What happens if you’re having difficulty inserting the fresh ETT? Well, the natural tendency is to push harder. Blindly shoving an ETT into the trachea increases the potential of damaging delicate airway structures. (3) Pneumothorax. A large series of patients undergoing airway exchange detected a pneumothorax rate of 1.5%.2 There are a couple ways that this can occur: First, if the exchange catheter is passed too deeply into the airway, it may puncture a bronchus, leading to a huge pneumothorax.3 I’ve seen this happen and it’s not pretty. In the heat of the moment there’s a natural tendency to advance the catheter too far (to avoid it’s falling out). Additionally, the airway exchange catheter may be inadvertently advanced while the fresh ETT is being inserted over it. Second, the exchange catheter may occasionally exit the endotracheal tube through the Murphy eye, causing it to veer off at a sharp angle that impinges against the wall of the trachea. This could cause the exchange catheter to perforate through the tracheal wall.4 (4) Esophageal intubation. There are a couple of ways this can happen: First, an extremely common cause of a “blown ETT cuff” is that the ETT has been pulled upwards out of the trachea. When the ETT is pulled out of the trachea there is a cuff leak, which is managed by insufflating more air into the ETT cuff. The leak often occurs intermittently, so the ETT cuff winds up getting overinsufflated with a ton of air over time (e.g., 50-100 ml). Eventually, what you’re left with is essentially an ETT that is functioning similarly to a laryngeal mask airway. If an exchange catheter is blindly passed through the endotracheal tube it may go into either the trachea or the esophagus. So, a blind ETT exchange may land the fresh tube straight into the esophagus. Second, even if the ETT is in the trachea initially, it is possible for the airway exchange catheter to loop around backwards as it is advanced (figure below).1 If the airway exchange catheter loops around, it’s possible that a blindly advanced ETT could wind up in the esophagus.
PulmCrit – Beware of the Risk of ETT Exchange
Highlights
- Risks of ETT exchange (1) Airway loss due to inability to replace the ETT. There’s no guarantee that a fresh ETT will pass into the trachea. Occasionally the fresh ETT may get hung up on the glottis (this usually responds to gentle 90-degree rotation of the ETT, but not always!). If you are unable to pass the ETT, this may cause a huge problem – especially if you aren't properly prepared with all your airway equipment at the bedside. (2) Laryngeal trauma. What happens if you’re having difficulty inserting the fresh ETT? Well, the natural tendency is to push harder. Blindly shoving an ETT into the trachea increases the potential of damaging delicate airway structures. (3) Pneumothorax. A large series of patients undergoing airway exchange detected a pneumothorax rate of 1.5%.2 There are a couple ways that this can occur: First, if the exchange catheter is passed too deeply into the airway, it may puncture a bronchus, leading to a huge pneumothorax.3 I’ve seen this happen and it’s not pretty. In the heat of the moment there’s a natural tendency to advance the catheter too far (to avoid it’s falling out). Additionally, the airway exchange catheter may be inadvertently advanced while the fresh ETT is being inserted over it. Second, the exchange catheter may occasionally exit the endotracheal tube through the Murphy eye, causing it to veer off at a sharp angle that impinges against the wall of the trachea. This could cause the exchange catheter to perforate through the tracheal wall.4 (4) Esophageal intubation. There are a couple of ways this can happen: First, an extremely common cause of a “blown ETT cuff” is that the ETT has been pulled upwards out of the trachea. When the ETT is pulled out of the trachea there is a cuff leak, which is managed by insufflating more air into the ETT cuff. The leak often occurs intermittently, so the ETT cuff winds up getting overinsufflated with a ton of air over time (e.g., 50-100 ml). Eventually, what you’re left with is essentially an ETT that is functioning similarly to a laryngeal mask airway. If an exchange catheter is blindly passed through the endotracheal tube it may go into either the trachea or the esophagus. So, a blind ETT exchange may land the fresh tube straight into the esophagus. Second, even if the ETT is in the trachea initially, it is possible for the airway exchange catheter to loop around backwards as it is advanced (figure below).1 If the airway exchange catheter loops around, it’s possible that a blindly advanced ETT could wind up in the esophagus.