Should You Connect an Ambu Bag to an Oxygen Tank?
Yes, you should connect an Ambu bag (bag-mask device) to an oxygen tank to deliver the maximal feasible inspired oxygen concentration during positive pressure ventilation, particularly during resuscitation and emergency situations. 1
Primary Recommendation for Oxygen Supplementation
During CPR and resuscitation, use 100% inspired oxygen (FiO₂ 1.0) as soon as it becomes available, as this optimizes arterial oxyhemoglobin content and oxygen delivery to vital organs. 1
The American Heart Association recommends using maximal feasible inspired oxygen concentration during CPR when supplementary oxygen is available. 1
Empirical use of 100% oxygen during brief periods of CPR is reasonable and does not cause clinically significant toxicity during the short duration of resuscitation efforts. 1
Optimal Oxygen Delivery Setup
To achieve near 100% oxygen delivery, you need proper equipment configuration:
Connect oxygen at 10-15 L/min flow rate to the bag-mask device's oxygen inlet port. 2
Use a reservoir attachment (2.5-L bag reservoir or demand valve) to consistently deliver FiO₂ of 1.0 (100% oxygen). 3
Without a reservoir, bag-mask devices deliver significantly lower oxygen concentrations even with supplemental oxygen flow. 3
Corrugated tube reservoirs should NOT be used as they are highly sensitive to variations in ventilatory technique and cannot reliably deliver consistent oxygen concentrations. 3
Critical Technical Considerations
Proper two-person technique maximizes effectiveness:
Use two trained providers when possible—one to maintain mask seal and airway patency, the other to squeeze the bag. 1, 2
Deliver 600 mL tidal volume over 1 second, sufficient to produce visible chest rise without excessive pressure. 1, 2
During CPR without an advanced airway, deliver 2 breaths during pauses after every 30 compressions. 1
Device Performance Variations
Not all self-inflating bags perform equally:
Research demonstrates large variations in oxygen delivery between different bag-mask models, with some delivering as low as 39% oxygen despite 15 L/min oxygen flow, while others achieve 99.5%. 4
Four out of six commonly tested models (Ambu and Laerdal brands) delivered high oxygen fractions, while two models (Intersurgical and O-Two) significantly underperformed. 4
This variability poses a serious threat to patient safety, particularly during resuscitation and emergency anesthesia. 4
Critical Pitfalls to Avoid
Excessive ventilation causes significant harm:
Avoid hyperventilation—excessive rate or volume increases intrathoracic pressure, reduces venous return and cardiac output, and increases aspiration risk. 2
Use only enough force to produce chest rise—excessive pressure causes gastric insufflation, gastric distension, diaphragm elevation, and aspiration. 2
Single-provider bag-mask ventilation during CPR is not recommended—use mouth-to-mask ventilation instead if alone. 2
Special Populations
For neonatal resuscitation:
Self-inflating bags can deliver titrated oxygen concentrations (21%-100%) by adjusting oxygen flow rates from 0.25 L/min to 5 L/min, useful in resource-limited settings without blenders. 5
With 5 L/min oxygen flow, all self-inflating bags deliver close to 100% oxygen regardless of peak inspiratory pressure. 5