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Ostomy Bags: Drainable, Closed, Two-Piece, and One-Piece

Before patient discharge from the hospital, an ostomy nurse should help you select an appropriate ostomy bag system. Do not overlook this step; unfamiliarity with ostomy supplies may be distressful. Depending on the type of ostomy (colostomy, ileostomy or urostomy), the ostomy bag you require will differ.

“Pouches come in a variety of styles and sizes that do not show under clothing. They are made of disposable materials and designed to be worn once and then discarded. Many colostomates wear a pouch. For example, those who have a transverse colostomy, those who do not wish to irrigate and those who have some output between irrigations.

Basically, they all do the same job. They collect stool that may expel expectantly or unexpectedly. Some are open at the bottom for easy emptying. Others are closed and are removed when filled. Others allow the adhesive faceplate or flange to remain on the body while the pouch may be detached, emptied or replaced. Pouch flanges are available in both convex and flat surfaces. Everyone, including those who irrigate, needs some type of stoma pouch on hand, if only for emergency purposes.

Ostomy bags are normally secured to a user’s body through a coupling which releasably connects the bag to a pad or dressing adhesively attached to the body. This coupling should allow ready entrance of a stoma into the bag, provide a tight mechanical seal to prevent leakage, and be readily released to assure the convenient replacement of the bag. In addition, the bag should be comfortable to the user.”.1

Despite an introduction regarding stoma care and suitable ostomy supplies, you will possibly face additional questions. Maintain contact with your ostomy nurse to understand how to use modern ostomy appliances.

“Modern ostomy appliances are commonly attached to the body by means of an adhesive wafer. The adhesive wafers most commonly used are designed to have a predetermined, fixed shape. The wearer cuts the central opening of the adhesive wafer to match his or her stoma size and shape, using scissors to cut along guidance lines that are pre-printed on the adhesive release sheet for certain standard sizes

Ostomy appliances of the so-called “two-piece” type are well known and consist essentially of an adhesive faceplate for adhesive attachment to the peristomal skin surfaces of a patient and a collection pouch that is detachably connectable to the faceplate. The faceplate and pouch have alignable stoma-receiving openings, and a pair of thermoplastic coupling rings are secured to the faceplate and pouch about such openings for connecting the parts together.

The advantage of such a two-piece appliance over a conventional one-piece appliance (in which a pouch and faceplate are permanently connected) is that a number of pouches may be used successively with a single faceplate. The user of a two-piece appliance may, therefore, leave a faceplate adhesively attached to the skin for an extended period, without the discomfort, inconvenience, and skin irritation that frequent removal and replacement of an adhesive faceplate may involve, and simply remove a used pouch and replace it with a fresh pouch whenever needed.

To be effective, however, it is critical that a two-piece appliance be free of leakage problems since even slight leakage of liquid, solid, or gaseous matter could cause considerable inconvenience and embarrassment to the wearer. Much effort has been expended in the past to develop coupling systems that are reliable and not likely to be inadvertently detached in use, are nevertheless easy to assemble and disconnect at will, and do not leak even when a number of pouch rings have been successively coupled and uncoupled from a single faceplate ring. While some existing appliances come closer than others to fully achieving these objectives, their effectiveness in doing so has generally come at the sacrifice of one further objective-that of providing a coupling assembly of low enough profile that it does not protrude an appreciable distance from a wearer’s body and does not produce conspicuous bulges through a wearer’s clothing.”2

One-Piece Ostomy Bag versus Two-Piece Ostomy Bag Systems

Ostomy bag systems are classified into two groups: one-piece and two-piece. A one-piece ostomy bag has the skin barrier attached to it (hence, one-piece). The skin barrier is the adhesive disc that affixes around the stoma and helps protect the peristomal skin. One-piece ostomy bags are easier to apply and faster to replace. They are inconspicuous under clothing. The user should replace these bags daily.

A two-piece ostomy bag comes with the skin barrier as a separate unit (hence two-piece). The skin barrier and ostomy bag are connected through a flange, a plastic ring that snaps into place. Although this system is more expensive than the one-piece, it becomes more economical, as it allows changes while maintaining the skin barrier in place. In this system, the user should change the after 2-5 days, whereas the skin barrier once or twice per week.

Both systems are equally effective, so the decision is based on user preference.

General Comparison

“In a so-called one-piece appliance, the adhesive wafer is permanently attached to the appliance, to the extent that the adhesive wafer cannot easily be separated without risk of damaging the appliance. A one-piece appliance is intended to be used as an integral unit. A complaint sometimes made about one-piece appliances is that it is not always easy for elderly, visually impaired, or non-dexterous persons to adapt the size of the central opening in the adhesive wafer, because the appliance obstructs access from one side.

In a so-called two-piece appliance, the adhesive wafer forms part of a separate body fitment component that is attached by a releasable coupling. A two-piece appliance permits the body fitment to be separated from the appliance without damage so that at least one of the components continues to be functionally usable. For example, the body fitment may remain in place on the body, and a replacement pouch mounted in place of a used pouch. While a two-piece appliance allows better access for adapting the wafer, a common complaint about two-piece appliances is that it is not always easy to align the components, particularly for elderly, visually impaired or non – dexterous users.

Improved one-piece or two-piece ostomy appliance including a moldable adhesive, in which at least a portion of the adhesive can be manually molded by the wearer, to provide a custom fit around the stoma. This alternative way of customizing the wafer offers the prospect of a better fit around the stoma than that obtainable by cutting along standard size guidelines. Achieving a good fit is desirable in order to reduce the exposure of the peristomal skin to stool exiting the stoma. Peristomal skin may be quite sensitive, and vulnerable to irritation or infection when contacted by stool. Stool exiting the stoma may contain digestive juices from the body, and such juices can also attack the peristomal skin resulting in excoriation. Contact by stool also progressively reduces the effectiveness of the adhesive. However, stomas have many different sizes and shapes. The advantage of a moldable adhesive as taught in is that the user can mold the adhesive to closely match the exact size and shape of the stoma.

In a form in which the appliance is implemented as a two-piece ostomy appliance, the wearer is able to access the moldable adhesive from both sides, including the non-body-contacting side, when the pouch is separated from the body fitment. This can enable the wearer easily to mold the adhesive by folding or rolling it back from the non-body-contacting side. However, access is more restricted when implemented as a conventional style of one-piece appliance3

Once familiar with the process, you may try different ostomy bag options. Do not settle until finding one that adjusts to your needs.

 Wafers, Closed-End and Open-End Pouches

“The method of attachment to the wafer varies between manufactures and includes permanent (one-piece), press-on/click (‘Tupperware’ type), turning locking rings and ‘sticky’ adhesive mounts.

The two-piece arrangement allows pouches to be exchanged without removing the wafer; for example, some people prefer to temporarily switch to a ‘mini-pouch’ for swimming, intimate and other short-term activities. Mini-pouches are suitable for minimum usage only.

For maximum hygiene and to reduce risk of infection, a one-piece (open-end) bag should be changed every twenty-four hours.

A two-piece bag’s base plate should be changed weekly with the bag changed every twenty-four hours.

Pouches can be broken down into two basic types: open-end (drainable) and closed-end (disposable).

 The use of open-end vs. closed-end pouches is dependent on the frequency in which an individual needs to empty the contents, as well as economics.

Gas is created during digestion, and an airtight pouch will collect this and inflate. To prevent this some pouches are available with special charcoal filtered vents that will allow the gas to escape, and prevent ballooning at night.”4

Advantages of the One-Piece System

  • “Less bulky and more discreet than a 2-piece appliance
  • More flexible, molds to creases in the skin – an advantage especially if the stoma is close to the navel, operative scar or crest of the hip bone
  • Fast and easy to replace
  • The skin surrounding the stoma can be cleaned at every change
  • Can be changed without the need to apply firm pressure to the abdomen


  • The skin suffers because the adhesive has to be removed at every change
  • The appliance may be difficult to place because the bag may block the view of the stoma
  • Changing the appliance can be a challenge for beginner.”5

Drainable Ostomy Bags versus Closed Ostomy Bag Systems

Ostomy bags may be further classified into drainable and closed. Drainable ostomy bags are open-ended and sealed with a clamp, clip, press, and seal, or velcro. They are simple to empty and wash. They are designed for those with frequent discharge (ileostomy patients), those with resection of the upper colon or those who can irrigate (some colostomy patients). Drainable ostomy bags should be emptied when half-full.

Closed ostomy bags are single-use. They are meant to be removed and discarded once full. Closed ostomy bags cannot be emptied. They are aimed at those with less discharge.

“Drainable ostomy pouches typically have flat opposing side walls secured together along their edges and defining a chamber for receiving body waste material. One of the walls is provided with a stoma-receiving opening, and means are provided for securing the pouch to a patient’s abdomen so that waste discharged from the stoma is received in the chamber. At its lower end, the drainable pouch has a discharge opening, usually provided at the lower end of a narrowed neck portion, and means are provided for maintaining the discharge opening in sealed condition until waste material is to be drained from the pouch. Such closure means may take the form of a clamp, or some device for securing the neck portion in upwardly-rolled condition. Conventional wire ties or wraps have been used for that purpose.

A drainable pouch is reusable and must be periodically emptied of its contents. Cleaning is necessary prior to reuse so that effective sealing can be assured and odors emanating from the resealed pouch can be avoided. Users often encounter difficulty and discomfort in unsealing, emptying, cleaning and resealing drainable pouches because of the direct exposure to waste matter and because the manipulations may require greater dexterity than a patient, particularly an elderly patient, can provide. Adding to the problem is the fact that residual amounts of Solid and/or liquid waste matter at the lower end of a drainable pouch tend to block or hold the walls of the pouch together, making cleaning of the inside surfaces adjacent the drain opening even more difficult.”6

Drainable ostomy pouches have a closure system that incorporate four closure parts and a two-part fastening system. “ The closure system is arranged on a neck portion of the drainable pouch and configured such that the pouch can be securely sealed after the neck portion is folded up three times and closed using the two-part fastening system.

The ostomy pouch may be a closed-end pouch for a single-use, in which case the entire pouch is discarded after it has been substantially filled with stomal discharge.” 7

On the other hand, open-end and closed-end pouches both offer multiple benefits for different types of users. “Open-end pouches have a resealable end that can be opened to drain the contents of the pouch into a toilet. The end is sealed Velcro-type closure at the end that eliminates the need for a clip.

 Closed-end pouches must be removed and replaced with a new pouch once the bag is full. This system can cause extreme damage to the skin area under the adhesive due to the frequency of removal and re-application. The use of open-end vs. closed-end pouches is dependent on the frequency in which an individual needs to empty the contents, as well as economics.”8

 How to Select the Correct Pouch?

“While usually closed-end pouches are reserved for those individuals with colostomies and formed stool, people with ileostomies may also choose to use closed ends. Poor hand strength and dexterity may make traditional clipped pouches difficult to use, while a closed-end system may facilitate self-care and independence. As with colostomies, there may also be events when or places where discarding a pouch may be easier than trying to empty.

Lastly, there are also one-piece closed-end pouches. These have a very thin barrier with less tack than traditional 2-piece systems. These are intended to not be worn more than 1-2 days (depending upon stool volume and frequency), and the whole appliance is removed and discarded. No paste is used with this type of pouching and is best reserved for those with formed stool. This system has a low profile and most closely mimics usual bathroom habits: the filled pouch is removed/discarded, stoma and skin quickly cleansed and a new pouch applied.

Many factors can influence selection. The length of the stoma, abdominal firmness and contours, the location of the stoma, scars, and folds in the abdominal area and your height and weight all must be considered in determining what is best for you. Special adaptations may have to be made for stomas located near the hipbone, waistline, groin, scars, etc.

Custom-made products to fit unusual situations can be obtained from some companies. The best pouching system for you is a very personal matter. It is important that you are properly fitted, just as for eyeglasses.”9

During the selection process of your first ostomy systems, consult with your ostomy nurse, specialist or another ostomate with more experience in this area, so you can make the correct choice for your requirements.


(1)       United States Patent. Johns. file:///C:/Users/Juan/Downloads/US4872869%20(1).pdf



 (4, 8) Ostomy bags.

(5)       UOA. Colostomy Guide.


(7)       Friske. Ostomy Pouch.

 (9)      OAA.

María Laura Márquez
13 October, 2018

Written by

María Laura Márquez, general doctor graduated from The University of Oriente in 2018, Venezuela. My interests in the world of medicine and science, are focused on surgery and its breakthroughs. Nowadays I practice my more:

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