In the Field
BVM is the universal manual ventilator. Every advanced airway capability presupposes BVM skill, because BVM is what you use to oxygenate the patient before intubation, between intubation attempts, and when other airway management fails. Effective BVM is harder than it looks. The mask seal is the limiting factor most of the time. Two-person technique (one person seals, one person bags) is dramatically more effective than single-person BVM and should be the default whenever staffing permits.
Common Mistake
Bagging too fast or too hard. Adult ventilation rate is 10 breaths per minute (one every 6 seconds), with tidal volume just enough to see chest rise. Excessive rate causes hyperventilation and cerebral vasoconstriction in TBI; excessive volume causes gastric insufflation, vomiting, and aspiration. The other mistake is single-rescuer BVM with a poor seal, which delivers most of the gas to the room instead of the patient.
Technical Detail
BVM components: self-inflating reservoir bag (typically 1000 mL adult, 500 mL pediatric, 250 mL infant); one-way patient valve preventing exhaled CO2 from re-entering the bag; oxygen reservoir bag for high FiO2 delivery (90 to 100 percent with reservoir attached to 15 LPM O2; 21 percent without supplemental oxygen). Adult tidal volume target 500 to 600 mL (6 to 7 mL/kg). Adult rate 10 breaths per minute for the ventilated patient. Two-person BVM technique uses one rescuer for jaw thrust and mask seal (thumb and index finger creating C-shape around mask, remaining fingers performing E-shape jaw thrust) while the second rescuer compresses the bag.
