The use of transcutaneous oximetry to predict complications of chronic wound healing: A systematic review and meta-analysis

Transcutaneous oximetry (PtcO2) has been proposed as a method to predict nonhealing of chronic wounds and the occurrence of healing complications. However, the validity of this method as an independent predictor and an optimal threshold value for this tool are poorly defined. We undertook a systematic review and meta-analysis to address these questions, searching five major medical databases, relevant review articles, and reference lists. We included all studies that used multivariable analysis to evaluate PtcO2 for its ability to predict chronic wound healing complications. Article selection and data abstraction were conducted independently and in duplicate. Four studies, enrolling 901 patients with 910 lower extremity chronic wounds, met our inclusion criteria. These studies showed that a peri-wound PtcO2 level below a cutoff of 20 mmHg or 30 mmHg was an independent predictor of chronic wound healing complications (odds ratio 3.21, 95% confidence interval 1.07-9.69, I-2 = 77%). A threshold value of 20 mmHg was used most frequently in the included studies and showed the strongest association. This review was limited by the small number of studies, a possible reporting bias, and heterogeneity. These results suggest that PtcO2 measurements have independent prognostic value in the assessment of chronic wounds, but further research is required to confirm these findings and define an optimal threshold value.