Double tourniquet use in foot surgery
Research type
Research Study
Full title
Reducing the physiological effects of the surgical tourniquet: a prospective randomised controlled trial
IRAS ID
169261
Contact name
Chandra Pasapula
Contact email
Sponsor organisation
Queen Elizabeth Hospital
Research summary
Foot and ankle surgery requires the application of tourniquet to create bloodless environment. There is limit to how long a tourniquet can be applied before serious ischemia occurs. It is generally accepted that the tourniquet time for lower limb procedures should not exceed two hours to reduce the risk of critical ischaemia and later compartment syndrome.
Apart from the risk of ischaemia, prolonged tourniquet time also leads to the typical physiological response of hypertension and tachypnoea, which usually occurs after 60 minutes of tourniquet use. These effects are associated with a hypercoagulable state; which is believed to be due to increased platelet aggregation as a result of catecholamine release. Although these changes are very difficult to reverse using medication alone, deflation of the tourniquet leads to rapid normalisation of the patient’s parameters.
Tourniquet pain and tourniquet induced hypertension are phenomena that can be exhibited by both awake (spinal) and anaesthetised patients; and thought to be due to the local effect of the tourniquet on the neural tissue in the skin. To explain this phenomenon, several theories have been postulated. It is thought that A-delta fibres are blocked by compression but C-fibres are more resistant to anaesthesia. Using a tourniquet therefore blocks the A-delta fibres which normally cause post synaptic inhibition of pain. In addition, the C-fibres in the skin under tourniquet pressure provide progressive pain stimuli. Therefore, unrestricted pain signals are sent as tourniquet time increases.
We seek to establish a novel double tourniquet technique, which will result in better control of the patient’s physiological response and reduce risk of tourniquet associated complications.
REC name
North East - Newcastle & North Tyneside 2 Research Ethics Committee
REC reference
15/NE/0063
Date of REC Opinion
13 Feb 2015
REC opinion
Favourable Opinion