Methylene blue staining: A novel application to identify the damaged tissues on the surface of pressure ulcers

Dear Editors,

One‐stage operation of multiple pressure ulcers was found to have a shorter recovery period and shorter hospitalisation without a significant increase in complications compared with the conventional staged operation.1 However, unnecessary and especially excessive surgical trauma to the patient must be prevented. This unexpected occurrence is seen when there is uncertainty regarding the limits of the non‐viable ulcer tissue that requires excision. This surgical predicament may result in either inadequate excision with failure of reconstructive surgery or excessive excision with unnecessary tissue and blood loss.

In 1980, Davies first found that methylene blue has the ability to colour the dead and damaged tissue on the burn wound surface.2 This effect has been used with success as a diagnostic aid during clinical and surgical assessment of the site, size, and depth of the injured zone in 20 dermal burn wounds. However, no case has previously been reported of the application of methylene blue staining on the pressure ulcer. In our study, for the first time, we are writing to share our own clinical experience of using methylene blue staining as an aid to identify the dead tissue layer before and during surgery on the pressure ulcer.

We present the case of an 82‐year‐old man admitted to the emergency unit with bradypsychia and multiple pressure ulcers for 2 months. He could not walk because of disuse syndrome but was able to seat himself in a chair. On physical examination, his right trochanteric area had an approximate 7 × 12 cm grade III pressure ulcer with crust formation because of a long‐term sitting or prone position (Figure 1(A)). The patient has a 10‐year history of hypertension and diabetes. Laboratory and physical examination, chest radiography, and CT scan of the head did not show any signs of neurological, respiratory, and cardiovascular abnormalities. After 20 days, methylene blue (500 mg silver suphadiazine 1% and 160 mg methylene blue 1%) was applied topically on the dermal pressure ulcer. The pressure ulcer involved less than 5% of the patient's skin surface. Within 24 hours, an acceptable colour change had been produced in what was considered to be non‐viable tissues (Figure 1(B)). Following ultrasonic debridement, the dead and damaged tissues were completely removed (Figure 2(A)). Right perforator‐based musculocutaneous rotation flap coverage was successively performed in the right trochanteric area (Figure 2(B)).3 At the 2‐month follow up, the pressure ulcer was completely healed without complications, such as flap necrosis, wound disruption, haematoma, seroma, and infection (Figure 2(C)). This case indicated that methylene blue staining also could be applied to identify the damaged tissues on the surface of the pressure ulcer. Furthermore, we created the first paradigm for the application of methylene blue staining in patients with pressure ulcers.

Figure 1.

(A) Pressure ulcers on the right trochanteric area; (B) within 24 hours, an acceptable colour change had been produced by methylene blue staining in what was considered to be non‐viable tissues

Figure 2.

(A) The dead and damaged tissues were totally removed; (B) right perforator‐based musculocutaneous rotation flap coverage was performed; (C) at 2‐month follow up, ulcerations were healed without complications