Background <p>Tracheostomy-related pressure injuries (TRPIs) compromise recovery and prolong hospital stay.</p> Methods <p>We conducted a prospective randomized controlled trial at a tertiary hospital to compare the efficacy of petroleum jelly application versus normal saline irrigation in preventing peristomal pressure injuries and promoting tracheostomy wound healing. This study enrolled 28 participants, aged 18–80&#xa0;years, who underwent tracheostomy procedures at Vajira Hospital, Navamindradhiraj University. They were randomly assigned using a permuted-block randomization methods (block size = 4) to either the petroleum jelly application group or the sodium chloride irrigation (0.9% NaCl solution) group. The outcomes were evaluated by one physician and one nurse at first, second, and fourth weeks postoperatively using the Pressure Ulcer Scale for Healing (PUSH) Tool and Skin Integrity Score.</p> Results <p>The petroleum jelly application group demonstrated significantly lower mean scores on the PUSH Tool at first, second, and fourth weeks than the sodium chloride irrigation group. Moreover, the petroleum jelly application group exhibited significantly higher median scores for skin integrity at first, second, and fourth weeks than the sodium chloride irrigation group. The interrater reliability between the two observers was good to excellent. The petroleum-jelly arm showed faster improvement on both scoring tools across all follow-up points.</p> Conclusions <p>The participants who received petroleum jelly application following tracheostomy demonstrated better results in preventing pressure injuries and maintaining skin integrity compared with those who received sodium chloride irrigation.</p> Trial registration <p>TCTR20240806002 (Thai Clinical Trials Registry), registered on August 6, 2024. Retrospectively registered. (<a href="https://www.thaiclinicaltrials.org/show/TCTR20240806002">https://www.thaiclinicaltrials.org/show/TCTR20240806002</a>).</p>