Preoperative transcutaneous oximetry predicted complications in sarcoma radiation

The use of preoperative transcutaneous oximetry may be useful in predicting wound-healing complications in patients undergoing surgery for soft tissue sarcomas after external beam radiation therapy, according to study findings.

This test may be useful in guiding decisions regarding the timing of radiation in relation to surgery, the researchers wrote.

Lukas Nystrom, MD, of Loyola University Medical Center, and colleagues evaluated 10 consecutive patients with lower extremity sarcomas suitable for preoperative radiation. The researchers measured the patients’ transcutaneous oxygen levels at five time points: before radiation, midway through radiation, at the conclusion of radiation, immediately before surgery and 2 weeks postoperatively.

Measurements were taken at five areas around the operative field and on the opposite limb. The time to surgery, on average, was 28.3 days, and the same surgeon operated on all patients using a standard wound closure procedure.

The researchers tracked wound complications and wound healing outcomes out to 4 months postoperatively and classified wound complications as major or minor. Complications requiring operative wound management, readmission for IV antibiotics, or the need for dressing changes or wound packing for more than 120 days postoperatively were defined as major complications.

Wound complications requiring aspiration of a seroma, an oral antibiotic regimen or dressing changes/wound packing for more than 4 weeks were classified as minor complications.

The researchers determined that there were three major wound complications, including one deep infection discovered 6 weeks postoperatively, one wound radiation necrosis diagnosed at 5 weeks postoperatively and one hematoma requiring drainage 2 months postoperatively.

The average mean oxygen measurement was 51.8 mm Hg before radiation, 57.1 mm Hg mid-radiation therapy, 53.3 mm Hg after treatment, 49.5 mm Hg preoperatively and 54 mm Hg postoperatively. The low preoperative oxygen of patients who did not have complications was 33.4 mm Hg vs. a low preoperative oxygen of 18.7 mm Hg in those who had complications.

None of the patients whose oxygen measurements were above 25 mm Hg at the immediate preoperative time point exhibited wound complications, whereas only 57% of those with oxygen levels <25 mm Hg immediately before surgery had complications.

“Transcutaneous oximetry represents a potential tool for decisions regarding surgical timing or potentially other medical and surgical efforts to diminish wound complications,” the researchers wrote. “However, given this small sample size, more data is needed to further assess the relationship.”

For more information:

Nystrom LM. Presented at the 2014 annual meeting of the Musculoskeletal Tumor Society; Oct. 9-11, 2014; Houston.

Disclosure: The researchers report no relevant financial disclosures.