The answer to this question is mostly about who decides.
For pressure sores, depending on the size and stage of the sore, you may use a film, gauze, gel, foam or another type of dressing. Talk with your provider about which one to use.
The same goes for the schedule. How often a dressing should be changed depends on the type of wound and the type of dressing, and some dressings are designed to stay on for up to a week. The dressing and the change schedule are chosen together, which is why you can’t sensibly pick one without the other.
The closest thing to a general rule is what a dressing is for. An appropriate dressing helps create the ideal wound healing environment — warm and moist — keeping the wound moist but not soggy.
For a surgical wound, it’s up to your surgeon. Your surgeon will tell you how often to change your dressing, and you can leave the original dressing in place for as long as your surgeon says.
Choosing between dressing types on your own isn’t something this page can help you do, and it won’t try. The choice follows from an exam — the type of wound, how much fluid it produces, what stage it is at — and that is the conversation to have with whoever is treating it.
Here is what that assessment involves. After a full assessment of you and your wound, the clinician needs to consider many different factors before choosing a wound dressing — including how well it absorbs fluid, whether it keeps the wound moist, how easy it is to apply, how long treatment will last, and cost. Factors they assess beforehand include how the injury happened, the risk of contamination, possible injury to deeper structures, underlying nerve or tissue damage, poor blood flow, tissue swelling, your tetanus status, how much tissue was lost, and whether there is infection.
This is a planned decision, not an improvised one. Many patients and family members are actively involved in wound care, but it needs to be discussed and planned with your healthcare professional.