This is another dogma I feel overdue for discussion. This is one practice that was instilled in our training when we were students: trauma/NPO non-compliant would get RSI with CP. Cricoid pressure was originally described by Sellick with the patient in a head down, tilted to the left position back in 1960’s. It was claimed that applying cricoid pressure could prevent passive regurgitation of gastric contents during an RSI. We have been following this practice ever since but it was not validated in a trial. How many times have you run into a situation where you have someone applied cricoid pressure and you only have grade 3/4 view. It happened to me several times in OB emergent c-section cases and trauma cases or the darn ruptured gallbladder cases. Several studies have shown that the use of cricoid pressure can impair laryngeal view and subsequently affect laryngoscopy to have a successful first pass. The use of CP is without risks itself. It has caused oesophageal rupture and exacerbation of unsuspected airway injuries. In Landsman’s article, it is demonstrated that the recommended pressure to prevent gastric reflux is between 30 and 40 Newtons (N, equivalent to 3-4 kg) to be effective, but pressures greater than 20 N cause pain and retching in awake patients and a pressure of 40 N can distort the larynx and complicate intubation. In addition, we can’t apply CP to every single patient who doesn’t meet NPO status. The use of CP is contraindicated in patients with suspected cricotracheal injury, active vomiting, or unstable cervical spine injuries.
Priebe HL wrote in his article that by using CP we may well be endangering more lives by causing airway problems than we are saving in the hope of preventing pulmonary aspiration. It is dangerous to consider CP to be an effective and reliable measure in reducing the risk of pulmonary aspiration and to become complacent about the many factors that contribute to regurgitation and aspiration. Ensuring optimal positioning and a rapid onset of anesthesia and muscle relaxation to decrease the risk of coughing, straining or regurgitation during the induction of anesthesia are likely more important in the prevention of pulmonary aspiration than CP.
This is a practice that doesn’t have its claimed merits. It could potentially cause more harm than the claimed benefits. I hope this post can reach you and make you aware of the dogma that we have and raise our awareness on this subject. We are practicing in 21st century but our non-validated theory that dictates our practice was based back in 1960’s. Therefore, if it is not evidence-based practice, this shouldn’t be considered a standard of care. It is time to challenge the guideline in our near future.
If you are torn over this issue, Please follow your institutional policy. Always do what is the best for the patient. It is time for us to re-evaluate the dogma!
Let’s keep lysing the dogma!
Ellis DY, Harris T, Zideman D: Cricoid pressure in emergency department rapid sequence tracheal intubations: a risk-benefit analysis. Ann Emerg Med 2007, 50(6):653-665.