Gerstein NS, Carey MC, Braude DA, et al. Efficacy of facemask ventilation techniques in novice providers. J Clin Anesth, 2013 May; 25(3): 193–7.
This study was designed to determine which of two facemask grip techniques for two-person facemask ventilation was more effective in novice clinicians: the traditional “CE” grip or a thenar eminence (TE) technique. In anesthetized patients in the operating room, with a ventilator delivering 500 mL tidal volume, 60 paramedic and medical students performed each technique (CE and TE) for one minute (12 breaths/min). The TE grip provided greater expired volume (379 mL vs. 269 mL), with a mean difference of 110 mL. The authors concluded that the TE grip results in improved ventilation over the CE grip in the hands of novice providers.
In emergency medicine and prehospital care, we spend a lot of time learning, practicing and debating the value of endotracheal intubation and less time and effort on the far more essential skill (from the perspective of the patient) of ventilation. Bag-mask ventilation is introduced in our first healthcare provider CPR class, quickly reviewed in EMT instruction, and in paramedic school is the brief procedure just before ETI. Rarely emphasized, briefly taught and never really tested (when was the last time you measured the inspiratory time, rate and tidal volume of your BVM ventilation?), bag-mask ventilation is an underappreciated and underemphasized skill.
The most important part of the procedure is the proper position of the mandible and creating an air seal between the mask and face. The traditional technique we all learned is “CE.” An alternative is the “thenar eminence” or “TE” technique, also called “two thumbs up” or “two thumbs down.” In the TE technique, four fingers are used to pull the mandible up while the thenar eminence (palm at the base of the thumb) pushes down on the mask to create the seal.
The TE technique has several advantages. First, it is easier to correctly position the mandible and mask using four fingers in a stronger mechanical position. Second, an air leak can be felt on the palms and corrected. Third, it is less fatiguing to use two hands in a more relaxed wrist position. The one disadvantage is that it requires two people to perform.
This is one of the few studies to compare the CE and TE techniques. A prior study [Anesthesiology, 2010; 113(4): 873–9] concluded that experienced anesthesiologists could deliver higher tidal volumes with TE. This study shows the same is true for novice practitioners. EMS systems should consider evaluating their ventilation training and performance, and consider adopting the TE technique as part of bag-mask ventilation.
Angelo Salvucci, Jr., MD, FACEP, is medical director for the Santa Barbara County and Ventura County (CA) EMS agencies and a member of the EMS World editorial advisory board.