Document Type

Theses, Masters


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Publication Details

Thesis submitted to the Technological University Dublin, in partial fulfilment of the requirements leading to the award of MPhil, 2016.


Introduction: Ulceration is defined as a breakdown of the skin. The treament of ulcers can be difficult and both time and cost expensive for the patient and health service. Determining what has caused this ulceration and formulating a treatment plan is key. There is no one universally accepted test which can accurately predict if a wound will heal or what treatment will be successful in healing it. Assessing the peripheral arterial system is an important first test to ensure that there is adequate blood perfusion to the ulcerated area. This is carried out by performing a test called Toe Brachial Indices (TBI’s).

In 2012 a new test called transcutaneous oximetry (tcpO2) was introduced to the vascular laboratory service in a bid to gain extra information on ulcer diagnosis and potential healing status. This test examines tissue oxygenation levels at a particular site. The purpose of this audit is to determine if tcpO2 provides any additional diagnostic information.

Method: From its introduction in 2012 and for the following three years all results of this test and a set of TBI’s were audited. Patients who presented to the vascular service with an active foot ucleration had both tests performed. A medical history was taken to record the risk factors of peripheral arterial disease.

Results: There were a total of 247 patients included in the audit which equated to 310 tests for anaylsis (a number of patients had tests performed on both feet). The age range was 32 – 94 years old with a mean age of 67.5 years and a median age of 69 years. Both tests were compared. tcpO2 and TBI’S were statistically lower in the smokers in comparision to the non smokers. Absolute toe pressures were statistically lower in the patients on statins and antihypertensives when compared to those not. Nether of these areas are well researched. When all test results were compared 70% of tests had reduced TBI results indicating arterial disease. Of this 70%, 39% had a tcpO2 result which was below a normal threshold suggestive that spontaneous healing was not likely to occur. This group with low TBI’s and low tcpO2 had significant numbers of interventions and amputations. More interestingly, the remaining 31% of tests had a tcpO2 test outcome which was above the normal threshold suggestive of spontaneous healing. These tests required a lower number of interventions and amputations when compared to the tests where both results are normal.

Conclusion: In the setting of peripheral arterial disease the addition of tcpO2 does provide additional further diagnostic information that should be taken into consideration with a TBI result when treating foot ulceration. In the absence of a TBI result it is reasonable to consider a tcpO2 test as an alternative source of diagnostic information.