 Basic life support training for CPR instructs potential rescuers in the proper use of mouth-to-mouth ventilation. In the hospital setting, however, rescue breathing is accomplished by ventilation through a mask or an artificial airway with a manual resuscitation bag. Manual resuscitation bags are devices used to support short-term artificial ventilation. They are frequently referred to by various terms such as self-inflating resuscitation bags, resuscitation bags, or anesthesia bags. They are also commonly referred to by popular brand names such as Ambu Bag, even though the actual bag you are using may be made by a different manufacturer. For the purposes of this training module, we will refer to these devices simply as bags. The process of using the bag to ventilate patients for short periods of time will be referred to simply as bagging. Bagging patients is required prior to and following intubation, during suctioning, during ventilator malfunctioning, and during patient transport. Additionally, bagging patients is required during emergency situations such as respiratory and cardiac arrest. In the event of ventilator malfunctioning, immediately disconnect the patient from the ventilator machine and begin providing manual ventilation. Call a respiratory therapist, physician, or nurse for help. Bag mass ventilation is a high-risk and technically challenging procedure and should be attempted only by experienced personnel. On the other hand, bagging a patient via an artificial airway is a relatively easy skill to learn and should be learned by personnel caring for ventilator-dependent patients. As always, wash your hands and follow standard precautions. In general, always wear gloves while bagging. You must assure that the proper size bag is utilized. The general rule of thumb is that adult bags are used for adult patients, pediatric bags are used for children less than 12 years of age, and infant bags for patients between birth and three years old. In this module, we will be focusing on manual ventilation of adult patients. The function of the bag is dependent on proper assembly and use of adequate flow of oxygen. Most bags come to the manufacturer pre-assembled, but assembly requirements will vary by manufacturer. Frequently, however, the practitioner only needs to attach oxygen tubing to an oxygen flow meter. Bagging patients is frequently used to provide 100% oxygen to critically ill patients. Therefore, the oxygen flow needs to be set at a minimum of 15 liters per minute. This is demonstrated here by adjusting the flow rate until the flow reaches at least 15 liters per minute. This is done whether the flow meter is attached to the wall or you are using a flow meter attached to an oxygen cylinder. Be sure to turn off the flow meter following use. To determine proper function of the bag itself, occlude the bag at the outlet with your thumb. Squeeze the bag with your other hand. You should feel resistance in the bag as the result of your thumb occluding the outlet. Simultaneously listening for air leaks. No air leaks should be detected with your thumb occluding the outlet. This assures that the bag's valves are functioning correctly. Remove your thumb. Squeeze the bag again. With the bag deflated, place your thumb over the outlet again. If the oxygen flow is adequate, the bag should reinflate quickly and completely within a few seconds, drawing oxygen from the reservoir attached to the rear end of the bag. As noted earlier, rescue breathing in the hospital setting is frequently accomplished by ventilation through an artificial airway. Note the artificial airway in place. This is commonly referred to as an endotracheal tube. This is a tube which is placed through the patient's mouth or nose into the trachea. Artificial airways are also surgically placed directly in the trachea through a tracheostomy. All three types of tubes, oral, nasal and tracheal, need to be adequately secured. This is usually done with tape or with string and should be done only by trained personnel. Prior to bagging, note the depth to which the endotracheal tube is placed. To do so, check the markings on the side of the tube. There are centimeter markings printed on the tube. Note the centimeter marking nearest to the closest anatomical landmark, such as the nares or nostrils from nasal tubes or the lips for oral tubes. The tube should remain at that depth at all times unless otherwise specified by a physician. Many patients are awake during this procedure. But whether you suspect the patient is conscious or not, you should explain to the patient that you will be taking him or her off the breathing machine for a short period of time. Be certain to reassure the patient that you will provide enough air to them with the bag during this period. Re-check to make sure the oxygen flow meter is set to deliver flow at at least 15 liters per minute. Connect the patient connector on the bag to the connector on the endotracheal tube or on the connector of the tracheostomy tube. Being careful not to pull, tug or dislodge the tube. Also be careful not to crimp the endotracheal tube. There are various methods you can use to practice bagging patients, such as using a test lung. There are many types of test lungs available with varying degrees of complexity. Some test lungs are not much more than sponge-like balloons shown here. A pressure monometer can be used to determine the amount of pressure you are generating with each squeeze of the bag. And a respirometer can be used to measure the amount of air or tidal volume that you are delivering to the patient with each squeeze of the bag. The frequency is determined simply by how often you squeeze the bag. Unless otherwise specified by the physician, you will usually squeeze the bag 12 to 16 times each minute or once every 4 to 5 seconds. While you must provide adequate ventilation at all times, studies have shown that there is a tendency to overventilate while bagging, so you must be careful not to hyperventilate the patient. Squeeze the bag with two hands. Note the pressure measured. Notice the harder and faster that you squeeze the bag, the greater the pressure you generate. High pressure can be very dangerous and even cause severe injury to the patient's lungs. Practice squeezing the bag so that pressures remain less than 35 centimeters of water. It is also very important to coordinate or synchronize the squeezing of the bag with the patient's own inhalation. And it is imperative to avoid squeezing the bag while the patient is exhaling or coughing, as doing so will generate very high pressure in the patient's lungs. The size of the breath, referred to as tidal volume, that you deliver to the patient is determined by how hard you squeeze the bag, and whether you use one hand or two hands to squeeze the bag. Squeeze the bag with one hand and observe the volume delivered. As you can see in this demonstration, 500 cc or .5 liter were delivered with one hand squeeze of the bag. Now squeeze the bag with two hands and again observe the volume delivered. As you can see, 1,000 cc or .5 liter of air were delivered with two hands squeezing the bag. The volume and pressure delivered to actual patients will vary based on the patient's condition. To help determine adequate ventilation, you should observe the patient's chest rise with each squeeze of the bag. Remember, you must also provide adequate time to allow for exhalation. Heart rate varying significantly from pre-bagging levels suggests insufficient or ineffective manual ventilation. The patient's color should remain normal or pinkish, indicating adequate oxygenation. Pulse oximetry may be used to monitor the patient during bagging. A pulse oximeter reading should be maintained at or greater than 90% throughout the procedure.