Transcutaneous oxygen pressure (TcPO2) is a non-invasive method for assessing tissue oxygenation. TcPO2 has several advantages, including its simplicity, low cost, and the ability to continuously monitor tissue oxygenation. However, TcPO2 also has several limitations that may affect its accuracy, including the influence of skin perfusion, skin thickness, and the presence of edema or necrosis. In this review, we discuss the advantages and limitations of TcPO2 in the assessment of tissue oxygenation, and provide recommendations for the optimal use of TcPO2 in clinical practice. Hyperbaric oxygen (HBO) therapy may be a useful adjunct in the treatment of patients with wounds associated with critical limb ischemia. These patients either cannot undergo a successful bypass or may not heal after vascular reconstruction alone. Identification of patients likely to benefit from HBO is essential before treatment, as this therapy is time-consuming, costly, and not without risk. Transcutaneous oxygen measurements (TCOM) can be used to evaluate the degree of hypoxia in ischemic tissue.