RESER VOIR BAGS

About RESER VOIR BAGS

Reservoir bags are bladder-type bags, made of latex-free material or silicone, ranging in size from 1L to 8L. The 3-L reservoir bag is the most frequently used in dentistry (Fig. 14.21). Although commonly used, latex-free bags deteriorate more rapidly than silicone bags, especially in areas in which high levels of atmospheric pollutants are found (the planet Earth).

The reservoir bag attaches to the base of the bag-tee, usually immediately below the emergency air inlet valve (see Figs. 14.19 and 14.21). A portion of the gas(es) delivered through the unit to the patient is diverted into the reservoir bag, where it may be used for any of several purposes.

The primary function of the reservoir bag during inhalation sedation is to provide a reservoir from which additional gas may be drawn should the respiratory demands of the patient exceed the gas flow delivered from the machine. During normal (quiet) respiration, the patient receives only fresh gases delivered from the sedation unit, with little or none taken from the reservoir bag. However, should the patient take an especially deep breath, the machine will be unable to accommodate the necessary volume; in the absence of the reservoir bag, the patient will experience a feeling of difficulty breathing. The reservoir bag prevents or minimizes this occurrence.

A second use of the reservoir bag during sedation is to serve as a monitoring device for respiration. Assuming an airtight seal of the nasal hood and no mouth breathing, the reservoir bag will inflate slightly with every exhalation and deflate slightly with each inhalation, permitting the operator to easily determine respiratory rate.