Background: Cricoid pressure is dead, right? Many have made this claim including a brilliant argument against its use by John Hinds here. Despite the many eulogies, we continue to hear about cricoid pressure so it makes sense that we dive in to the background prior to addressing the recent JAMA Surgery publication.
Cricoid pressure was first described by Dr. Sellick in the 1960’s though similar techniques were described as far back as the 1770s (Sellick 1961). The Sellick’s maneuver entailed the application of pressure over the cricoid cartilage with the thumb and 1-2 additional fingers. The goal was to compress the cricoid cartilage against the esophagus in order to occlude the esophagus and prevent regurgitation of stomach contents into the upper airway. Initial studies on the maneuver suffered from a bevy of methodological flaws including small n, lack of blinding or randomization and selection bias. Despite this, Sellick’s maneuver was widely adopted and taught to hordes of anesthesia, critical care and emergency residents.
Studies investigating cricoid pressure in the last decade have demonstrated a number of issues with claims that it can prevent passive regurgitation. Check out this free chapter on EMRAP for an in depth discussion. Dynamic MRI studies demonstrate that application of pressure to the cricoid cartilage displaces the esophagus laterally instead of occluding it (Smith 2003, Boet 2012). An ultrasound study demonstrated similar findings: in 60% of patients the esophagus was lateral to the airway and cricoid pressure led to displacement rather than occlusion in all patients. (Tsung 2012).
Additionally, application of cricoid pressure decreases airway patency and increases the chance that your view of the airway will be obscured. (Allman 1995, Palmer 2000, Smith 2002, Oh 2013). Finally, no study to date has demonstrated a reduction in aspiration episodes with the application of cricoid pressure. A large observational study of pregnant patients undergoing C-sections found no difference in aspiration events and that the overall aspiration event rate was low (Fenton 2009). However, up until this point, there has not been a high-quality, randomized controlled trial performed. Read more →