Pressure ulcer staging



The key difference between this type of ulcer and an unstageable pressure ulcer is that SDTI involves intact skin, whereas an unstageable ulcer involves a breakdown into at least the subcutaneous tissue. An unstageable ulcer is covered with necrotic tissue, such as slough or eschar, formed from remnants of the collagen matrix of subcutaneous tissue. So it’s always a full-thickness ulcer—either stage III or stage IV.

An SDTI tends to confuse clinicians because of the “intact skin” criterion. Damage from an SDTI occurs at the soft-tissue interface and extends out toward the skin surface. The skin remains intact, but the damage has occurred deeper than the eye can see and involves full-thickness structures. If an SDTI opens, the clinician stages the ulcer based on the tissue type and/or structures assessed in the wound bed.

Do you see staging being done correctly in the field? Do you have any tips on staging pressure ulcers?

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  1. Does a wound bed have to be completely covered with eschar or slough to be considered upstageable? I have a nurse at my agency that says it does.

  2. Tara, no it doesn’t. Sometimes you may have only 80% necrotic tissue in the site and 20% granulation tissue that would still be unstagable cause you really don’t know what is underneath the 80% necrotic tissue. What I usually say is “ride the unstagable ride” til you are professionally comfortable with putting a stage on it. So wait til you are able to see some “identifiable tissue/structures” present before putting a stage to it.
    What I have seen in the field is that many see the necrotic tissue being removed and call it a st.III, then once all the necrotic tissue is removed they now see bone and now have to up-stage it to a IV. Which only red flags the facility that they made the wound worse. Hope this helps. I have a free 1 hr pressure ulcer staging webinar on my website: click courses and locations…….then click webinar. Thanks for your post!

  3. I should have read this sooner. Good info. I did not know that we could stage an ulcer from unstageable to either a 3 or a 4 after the tissue became visable. Same goes for DTI.

    Thank you.

  4. Please, I need clarification: If I have a surgical wound left open to heal by secondary intention and it develops eschar in it is it considered unstageable? I thought we could only stage pressure ulcers.

  5. Hi Jane if u have a surgical wound example abd incision that experienced dehiscence and it has necrotic tissue and left to heal from secondary intention it wouldn’t be stageable. Only wounds caused by pressure should be stageable.

  6. Can a wound go from a stage two or three to unstageable? I have a resident with a wound that was a stage two and now it is covered wtih slough.

  7. Brooke,
    Yes, a stage II or III pressure ulcer can progress to unstageable. Check out this article on pressure ulcer staging, as it explains why..

  8. Can SDTI evolve into an unstageable wound?

  9. Hi Jane,
    Yes a SDTI can evolve into an unstageable Pressure ulcer…Once it opens up, it is no longer intact – the wound bed is covered with necrotic tissue, slough or eschar…the pressure ulcer now meets the definition for unstageable per the NPUAP guidelines and would be coded as such! Keep on healing!

  10. The pressure ulcer faqs sheet states that a stage 3 is deeper than a DTI. How do you know that? Couldn’t a DTI open up into a stage 4?

  11. Hi Sally….
    Yes, technically a sDTI could open up and either be a stage III or a stage IV, or sometimes, they resolve without opening if we are lucky… and you are right, the fact sheets do say that a stage III is deeper than the sDTI or DTI, why? Per the NPUAP, pressure ulcers are classified according to the amount of “visible tissue loss” – that is the key- and with our DTI’s, we don’t have a definite- its intact and discolored – but we aren’t sure the depth of the destruction quite yet! It has to open up for us to be sure… Good question :)
    Keep healing!

  12. Can a wound start out as unstageable and then at discharge be marked as healed? How would you answer the wound area on a discharge oasis?

  13. I recently encounter a situation where a heel pressure ulcer was identified as a SDTI(purple in color) by a nurse and the next day the wound doctor diagnosed it as an unstageable necrotic pressure ulcer-100 % black necrotic tissue. Is it possible for a SDTI to become eschar over night? Also concerned that the wound was initially found in such a state of development.

  14. Hi Celinda,
    I can’t help but question the initial assessment on both parties nurse and doctor. I would investigate this. I suspect it was mis-staged. I think its time to do some detective work to drive down what was really in place at the time for both clinicians.
    Questions I would uncover-if its was a SDTI what was the assessment findings to justify a true SDTI was it intact, purple, or blood filled blister? Was the area palpated to identify if it was soft, boggy etc. Was there a opening was there any drainage at the time of assessment if so then it wasn’t a SDTI etc etc ask the questions to drive down what was really there.
    Also when MD stated necrotic tissue what type of necrotic tissue was present was it is slough (soft hydrated stringy) or was it eschar (firm, dry, hard) this will help you time line this better. If the area that is affected has damage min. to the SubQ it will turn into slough first then into eschar if left open and unattended. How much of the site had necrotic tissues 25 % 50% or 100%. Once you have all your detective intell I am almost positive you will find the answer you are looking for…which may be mis-staged to begin with.
    This is perfect time to do a inservice on wound assessment as well.
    Hope this helps.

  15. HI,

  16. Hi Andrea, You should document length then width then depth.
    Like this:
    L X W X D
    So for instance if its 2.0 x 2.0 x ____cm
    Hope that helps.

  17. I was taught by various resources that if a wound is unstable able,when it becomes clean it should be documented as a healing unstage able. The reason from all sources is that you can’t ever say what stage it was from the beginning so to stage it a 2 when you can,t prove it wasn’t a 3 or 4 is misleading. I have also had Dept of Health staff agree with this as well. I’m in a different area and now I’m told to stage a wound once the Escher is gone. I’m confused. Help!

  18. An unstageable pressure ulcer per the National Pressure Ulcer Advisory Panel guidelines ( states that it is a full thickness tissue loss where enough of the base of the wound is covered with slough or eschar that you cannot really see the true depth of the tissue destruction – meaning I (the clinician) can’t tell if the damage is just to the subcutaneous tissue layer –definition of a stage III or if muscle tendon bone is present – definition of a stage IV pressure ulcer; therefore until I debride and remove the necrotic tissue, I call this pressure ulcer “unstageable”. This Unstageable stage is used more like a temporary stage until I can properly assess how bad the tissue damage is and properly stage using the NPUAP staging guidelines and their definitions.
    Once I debride (except on stable intact dry heel eschar, no debridement there) the unstageable PU– I then reclassify that PU based on the tissue type in the wound bed, -it will be either a Stage III or Stage IV as the level of destruction per the definition is “full thickness”…
    Once the PU is staged appropriately (stage III or IV), this is where we don’t “back stage” or “reverse stage”, for example as the pressure ulcer fills in with granulation tissue, the depth of the ulcer becomes more shallow and the ulcer heals we don’t say it goes from a stage IV to a stage III to a stage II etc- that was known as back staging or reverse staging and we don’t do it…. full thickness wounds only fill with scar tissue (granulation tissue) we don’t regenerate the subq or muscle we lost, so this is where we document a healing stage III or a healing stage IV, the “Stage” of the pressure ulcer will stick with it until it closes….
    Hope that helps….

  19. Hi Nancy,
    I have a Pt.with what I believe is a SDTI on the Left Medial Heal. The area is Purplish, Boggy, but intact,and painful to touch. I have made an appt for eval with the Pt’s Podiatrist, but she will not be seen for 1 1/2 months. The pt has been Instructed on pressure relief,and diet. My question is should this area be covered ( Meplex foam ) or left ota? Pt is mobile in a wheel chair.
    Just some back ground this Pt is also being TX for a Vascular Ulcer on the Medial lower leg with Meplex foam, and Tubi Grips ( these are low level compression stockens ) to help control the leg edema. What is your feeling regarding the Tubi grips over the heel SDTI?
    Thanks in advance for any input.
    Jim M

  20. Hi Jim,
    If you are dealing with an intact dark purple/maroon area caused by pressure as you described above, then it sounds like an sDTI. The best plan of care will involve totally offloading the area while in bed and while out of bed, especially since your patient is mobile in the wheelchair. You need to evaluate the foot wear/ offloading device you have in place both in bed and out of bed for sure. Make sure you have a pain management program in place, and continue to address the nutritional needs as this patient has multiple wounds.

    Given the fact that your patient has a vascular ulcer and requires compression, have you done a recent ABI? I am just wondering if she still has good blood flow or if the patient might now have from some arterial insufficiency, either way its time to repeat the ABI to be sure we are dealing with just a pressure ulcer and also need to be sure we have good blow flow to heal it up. Part of the treatment plan will be managing the wound bed, with a sDTI it is intact; so you really don’t need an absorptive dressing like a foam, you could use skin prep to help protect the area, and gauze with roller bandage if you feel it needs to be covered for dignity (this is more cost effective)and will still keep it dry and intact. If the ulcer opens we re-classify it and reassess the treatment at that time.

    The most important thing is to remove the pressure and offload at all times -no pressure. As far as the compression stockings, I am thinking given your patients pain, I would hold off on them at this point. They are adding to the pressure and the pain, re-check that ABI again. You can elevate your patient’s legs to help control the edema while you can in the meantime…
    Good luck!
    Nancy WCEI

  21. I’m still confused
    If someone were to have a blood filled blister on the heel how would it be staged? Would it be classified as SDTI of would be in one of the pressure ulcer stages like a stage 2?

  22. Beatriz,
    If an area of tissue injury is caused by pressure and is dark purple or maroon in color, and is INTACT or is a BLOOD filled blister then per the NPUAP staging definitions it will be staged as a sDTI Pressure ulcer. A stage II is much different than the above definition, a stage II is partial thickness – superficial open area, damage is into the dermis, or it could be a ruptured or intact CLEAR serum filled blister.
    Hope that helps :)
    Nancy WCEI

  23. I work in a LTC/Rehab facility. I see a lot of patients with denuded skin to the buttocks. What is the best treatment of choice?

  24. Jackie,
    One of the first things that should always be done with any wound, is to identify the CAUSE and either remove it or control it. If the cause is not controlled, the wound will not heal. In your case it sounds as if moisture is the problem. Once the moisture is controlled a barrier ointment or a no-sting barrier film
    should be applied to protect the skin. Here is a link to an article that discusses various options for treatment:
    Hope this helps!

  25. If I have a resident with a SDTI on admission and it changes to a Stg III when it opens is it considered “worsened” and now in house acquired or is it still out of house acquired because we didn’t know what was in the wound on admission because the skin was intact?

  26. Hi Amy,
    A stage III is worse than a SDTI as far as NPUAP pressure ulcer staging guidelines goes, as SDTI is intact skin and a stage III is tissue destruction into the subcutaneous tissue. On the MDS 3.0 you will code based on the instructions in section M0300; where it states: if the wound is present on admission and gets worse during the stay, it is no longer considered present on admission (meaning-the facility can no longer say the pressure ulcer was present on admission and from the hospital) and will be now coded at the higher stage.
    Always refer to the MDS 3.0 user manual for specific instructions. As far as “facility acquired” vs “hospital acquired” when a patient acquires the ulcer in your facility is when you consider that patients pressure ulcer “facility acquired”. Hope that helps!

  27. Can an unstageable ever be considered a stage II after the slough is gone, if all of the slough was removed at the same time? Or does it always need to be a stage III or IV?

  28. Hi Vicki,
    An unstageable PU will only ever be a stage III or IV once the necrotic tissue is removed, it can never be a stage II. Necrotic tissue is significant for full thickness tissue damage (stage III & IV) Necrotic tissue forms when my subcutaneous tissue layer dies, it turns into slough or eschar. That is why we will never see necrotic tissue in a stage II, remember as a stage II tissue damage is only into my dermis.
    The unstageable PU on the other hand involves deeper tissue destruction (into the subcutaneous and possibly deeper) where we can see necrotic tissue formation. So once debrided it will be either a III or a IV and you’re right, it will always stay a III or a stage IV for the life of the PU/patient.

  29. Nancy,
    Do you recommend any protective treatment for a SDTI, besides offloading?

  30. @Sue “off load” is the key to help with SDTI.

  31. Can a DTI as its healing become a STII ?

  32. Sorry let me clarify stage II (STII)

  33. Question:
    I am following a wound that started as a DTI on the heel approx a year ago. today is has appearance of a callous. the tissue around the wound looks completely normal and there is no pain in the area at all. When can I say this wound is resolved? knowing I will need to continually monitor this area.

  34. @Tammy Definition of a healed pressure ulcer according to CMS RAI Manual for Long Term care: Completely closed, fully epithelialized, covered completely with epithelial tissue, or resurfaced with new skin, even if the area continues to have some surface discoloration. Document all your findings along with pain assessment and interventions for prevention.

  35. Hello. If a PU goes from unstageable to stage stage IV, but then deteriorates to have a slough covered wound base again, is the stage changed back to unstageable? If not, how would you document its staging? “Stage IV pressure ulcer with slough” or “Deteriorating stage IV pressure ulcer” or …?

  36. @Mark…….if you historically found this to be a St. IV……then it covers up with necrotic tissue (slough or eschar) its still going to be a St. IV.
    Example for documenting just state the tissue type you see before your eyes.
    St IV R Trochanter has 85% yellow slough and 15 % black eschar. (Just percentage the tissue type you see out in the wound bed make sure you add up to 100%) This is a easy way to break out what you see in the wound bed.
    Hope that helps!

  37. In the past, our facility staged all fluid filled blisters as stage 2, regardless of the etiology or location of blister. Do you have any information or suggestions that would be beneficial to help with this issue?

  38. Hi Kathy, the best advice I can give you is when you see a fluid filled blister try to figure out what “caused it” to begin with….that is what you would label it as. Example: If its cause by pressure of a device-tubes, bed pan, O2 masks, shoe and or positioning then it would be stagable as a st. II because it was caused by the pressure of these things. Non pressure examples would be disease process, traumatic wounds, burns-heat,chemical etc. Hope that helps! Thanks for your post!

  39. Hello, i am dealing a client who is on end of life cares. sustained a SDTI, and a few days later turned into Kennedy ulcer as it is a pear shape, red color and black spots scattered all over the wound. Usually, client with Kennedy ulcer clients will passed away within few days, but this client is still in the process of dying. we are just keeping the wound clean, managing with polysporine ointment and optifoam dressing and maintaining the comfort. Is this is good enough or i should be doing something?

  40. Hi Jas,
    With our Kennedy Terminal Ulcers we treat and manage/stage them the same as our pressure ulcers. So we will keep the wound bed warm and moist, manage the exudate, manage the bacterial load etc. With the SDTI – if still intact, there probably isn’t a need for Polysporine ointment, unless the PU has opened and you are treating a local wound infection. With the SDTI we normally try to keep it intact and dry, offload as much as possible, to prevent it from opening up by skin sealant and by using the appropriate pressure redistribution support surface such as low air loss. With our palliative care patient we are still upheld to the same standards of care, guidelines and for treatment but our focus often changes from one of healing to one of comfort as many of these wounds we may not be able to heal, we always try to heal by using standards of care but secondary goals may be ones like preventing decline, preventing infection and managing pain. At this time honoring patients wishes at the end of life is crucial as well. Good luck!

  41. Unstageable pressure injury malodorous heavy exudate end stage MS patient. What do I treat with?

  42. There are many options for treatment of an Unstageable malodorous pressure ulcer with heavy exudate.. Since it is Unstageable there must be be some necrotic tissue in the wound bed. How you debride this wound is your choice. The gentlest method is autolytic debridement which can be accomplished by the use of dressings that keep moisture on the wound bed. Depending on your patient’s individual characteristics, you could also choose enzymatic debridement (SANTYL) or irrigation, or even sharp debridement. The odor can be addressed in a variety of ways. You can use antiseptics to kill the bacteria that are often causing the odor. Products like Dakin’s solution or Acetic Acid can help reduce the odor and should be used for a period of 2 weeks and then other methods can be used. Charcoal based dressings are available from Hollister, Convatec and others that function to trap the odor molecules within the dressing.
    Another option is to pouch the wound with a wound or ostomy pouch device. Pouching contains the odor and the odor should only be detected when the pouch is changed or emptied. Pouching can also manage the high levels of exudate. Exudate management can also be accomplished by the use of highly absorptive dressings like Aquacell. Extrasorb, and many others in the category Speciality Absorptive Dressings. Alginates is another category of dressings that are highly absorptive and can be used as well: Algisite M and many others from various manufacturers fit this category.
    You will also need to address wound pain in this patient. Traditional pain meds can be used as well as local Lidocaine preparations to numb the wound margins.

  43. Patient entered our facility with multiple pressure ulcers. There is a dark red blister looking area on the heel, the size of a silver dollar. The staff said it was a DTI, but then it opened and bled slightly, the wound bed is red, no subcutaneous or deeper tissues involved. Is this a stage II. …. or is it a DTI ?? Thank you

  44. Hi Lydia,
    Its no longer a DTI…….because a DTI definition states it has to be “intact”.
    Now you have a open active wound and if caused by pressure it would be a stage 2 if you don’t see any granulation tissue (bumpy granular type tiss).
    Hope this helps!

  45. I’ve had a foot ulcer on the ball of my left foot. I off loaded the foot via crutches and it healed. Every time I go back to walking it looks a blood blister generates under the skin and then cracks and opens into another wound. I have custom orthotics as well as proper footwear and see a chiropodist every week for debridements.

    I have a neuropathy where I dont feel much pain from my waist down but dont have diabetes and otherwise healthy. Please help! I can’t live on crutches the rest of my life.

  46. Hi Derek, I hear your frustration as it can be very challenging. I really can’t do alot of advising on this forum. However I would make sure you are definitely working locally with your MD or DPM (foot doctor) on this. So they can monitor you closely and investigate further.

  47. I have definitely been working with them but I feel as if it is the same process over and over and nothing come of it, just re-occurring ulcer on the same location. Even when I bring it up that I feel like the current path is not going to solve the problem they scratch their head and keep going with the same regiment. I am willing to try anything at the moment.

  48. Have a patient with DTI that opened and is only 30% unstagable in its opening. Is enzymatic debridement (Santyl) and mepilex dressing appropriate for this person. Or will mepilex absorb ointment?Concerned because pt is already very high risked and on dialysis!

  49. Christina,
    Without knowing all the patients history and wound information, we can not tell you if Santyl is appropriate for your patient. However here are a couple thoughts:

    1) Santyl is a daily treatment,most all foam dressings are designed to stay in place for several days, so using a foam dressing daily over the Santyl may not be the most cost efficient use.

    2) To determine if Mepitel would absorb all the Santyl, I encourage you to contact a representative from Mölnlycke Health Care for specifics.

  50. Hi! I am reviewing a chart and the nurse documented “Stage SDTI.” She also charted length and width in cm. Also documented “periwound pink.” Is is safe to say that this is a Stage I pressure ulcer?


  51. Have a patient that had a stage II pressure ulcer, the wound progressed to what appeared to be a stage III. The wound is now beginning to granulate at the edges. However, there is the formation of a white gelatinous “plug” over 50% of the wound bed. It is not hard but is somewhat soft. It doesnt appear to be slough. I was wondering what this was. Our wound care consultant said it was collagen material. Is this true?

  52. Stephanie,

    If its a DTI the affected site should be intact purple/maroon in color caused by pressure. IF so its a DTI.

    If periwound is pink but the wound itself is intact purple/maroon then its a staged as a DTI. And describe the periwound tissue as a separate standalone assessment. Example: Erythema located 12 to 12 o’clock measuring 2.5 cm

    Hope that helps.

  53. Hi,

    A few thoughts without seeing this or knowing more about it:

    Not sure what depth you have but if the wound bed is flush to the wound edges and looks like a cloudy thin white/pearly color or translucent layer moving in from the edges and trying to cover over top of the wound that might be re-epithelialization. Here is a link to a pic look at #B!po=27.5000

    If there is depth and you see whitish/yellowish type of tissue that would be most likely slough.

    Hope this helps,

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