Use of Noncontact Low-Frequency Ultrasound in Deep Tissue Pressure Injury: A Retrospective Analysis

The purpose of this study was to examine the effect of noncontact low-frequency ultrasound (NLFU) on deep tissue pressure injury (DTPI), both hospital-acquired and those present on admission (POA).

Retrospective, descriptive study.

Medical records from 44 adult patients with a DTPI treated with NLFU were reviewed; 22 had a hospital-acquired DTPI (HADTPI) and 22 had DTPI POA. Their mean age was 71.3 ± 16.3 years (mean ± SD); 52% were male. The study setting was a 318-bed community hospital in the Mid-Atlantic region of the United States.

Data were collected from the medical records including demographic and relevant clinical characteristics, DTPI measurements, and DTPI evolution/resolution. Data were summarized and examined using descriptive statistics (eg, frequencies and percentages and means and standard deviations). Differences between groups were examined using paired t tests or the Mann-Whitney U test and the chi-square test as appropriate. In addition, the heel DTPI subgroup (N = 8) was examined separately due to the small sample size.

All patients with HADTPI and DTPI POA treated with NLFU exhibited a statistically significant decrease in injury size from initiation to discontinuation of NLFU therapy (24.6 cm vs 14.4 cm, P = .02). No statistically significant difference in wound resolution was found between HADTPI versus DTPI POA (27% vs 18%, P = .47). Mean size of both HADTPI and DTPI POA decreased significantly from 15.9 to 13.4 cm (P = .045) by NLFU therapy. Wounds were classified as resolved at completion of treatment in 23% (10 out of 44) of all treated patients. Of all patients with the potential to be resolved (not discharged early or expired) 63% (10 out of 16) had wounds classified as resolved.

Study findings suggest that NLFU is a viable and promising treatment option for both HADTPI and DTPI POA. Future studies are needed to confirm these results and to examine efficacy and feasibility of DTPI across care settings.