Evaluation of toe pressure and transcutaneous oxygen measurements in management of chronic critical leg ischemia: a diagnostic randomized clinical trial

Abstract

Objective: The definition of critical limb ischemia (CLI) requiring vascular intervention is still under debate. The clinical eye of the physician and ankle blood pressure measurements used so far may fall short in appreciation of the severity of disease, which makes decision-making for a vascular intervention subjective. In previous studies two simple functional tests, ie, transcutaneous oxygen pressure (tcPo(2)) and toe blood pressure (TP) measurements, provided reliable information about the need for vascular intervention. Therefore we evaluated the diagnostic value of tcPo(2) and TP in management of clinically suspected critical leg ischemia. Study design This was a diagnostic randomized controlled clinical trial. Subjects were ambulatory and hospitalized patients in a referral university hospital.

Methods: Ninety-six patients (128 legs) with clinically suspected critical limb ischemia were referred to the vascular laboratory for routine investigation. Two diagnostic management strategies were compared: conventional strategy, ie, clinical judgment and ankle pressure determined the diagnostic and therapeutic approach, and a new strategy in which tcPo(2) and TP determined the diagnostic and therapeutic approach. Main outcome measures included clinical outcome, defined as pain relief, wound healing, and limb survival.

Results: At 18-month follow-up, 26 of 62 legs treated with the conventional approach and 28 of 66 legs treated with the new approach were treated conservatively. The new method did not score significantly different from the conventional method insofar as clinical outcome: pain score, 50 versus 48; number of amputations, 8 versus 10; and number of deaths, 11 versus 8 deaths, respectively.

Conclusion: Two simple objective diagnostic tests, TP and tcPo(2), did not improve clinical outcome when incorporated into routine management of suspected critical limb ischemia. Nevertheless, these techniques might still be helpful for physicians less experienced with treating critical limb ischemia and who are in doubt regarding the need for vascular intervention.