Effect of ischaemic pre-conditioning on cardiac function during elective open abdominal aortic aneurysm repair

• Register: ISRCTN
• Last refreshed on: 13 January 2015
• Main ID: ISRCTN58848790
• Date of registration: 29/09/2006
• Prospective Registration: No
• Primary sponsor: Record Provided by the NHSTCT Register - 2006 Update - Department of Health
• Public title: Effect of ischaemic pre-conditioning on cardiac function during elective open abdominal aortic aneurysm repair
• Date of first enrolment: 31/03/2006
• Target sample size: 40
• Recruitment status: Completed
• URL: http://isrctn.com/ISRCTN58848790
• Study type: Interventional
• Study design: Randomised controlled trial (Treatment)

Countries of recruitment

United Kingdom

Contacts

• Name: Vilas Navapurkar

Key inclusion & exclusion criteria

Inclusion criteria: Any patient scheduled to undergo elective infra-renal aneurysm repair will be eligible for inclusion. The following entry criteria with respect to renal function shall apply:
1. No history of acute renal failure
2. No history of renal replacement therapy (haemodialysis, haemofiltration, peritoneal dialysis)
3. No previous renal transplant
4. No previous renal disease
5. Serum creatinine less than 150 micromols/L at pre-operative assessment
6. Serum urea less than 20 mmols/L at pre operative assessment
Exclusion criteria: 1. Patients with aneurysms above the level of the renal arteries have a very high risk of renal damage during surgery. These aneurysms are relatively uncommon. Their inclusion could bias the trial.
2. Patients with lower limb amputations will be excluded as they have less muscle in their lower limbs. Thus, the IPC stimulus could be inadequate and bias the trial results.
3. Patients with ankle-brachial pressure index < 0.7 will be excluded as the IPC technique could trigger acute lower limb ischaemia.
4. Patients who have undergone previous endovascular repair of the aneurysm will be excluded.

Age minimum:
Age maximum:
Gender: Not Specified

Health Condition(s) or Problem(s) studied

Surgery: Open abdominal aortic aneurysm repair
Surgery
Open abdominal aortic aneurysm repair

Intervention(s)

The technique of IPC temporarily reduces the blood flow to the patients legs in sequence for five minutes at a time. This causes the muscle in the patients legs to release various chemicals that can protect tissue against damage due to periods of reduced blood and oxygen supply. Once blood flow to the leg is fully restored, these substances enter the general circulation and can protect distant organs such as the heart, brain or kidneys from damage due to reduced blood flow. The Vascular Research Unit at Addenbrookes Hospital has shown that IPC reduces the levels of a protein in the blood called troponin I which is a marker of heart muscle damage.

We would like to investigate the effect of IPC on heart function by using established perioperative cardiovascular monitoring techniques.

IPC is not standard practice in major vascular surgery at present.

The Vascular Research Unit is undertaking a randomised controlled trial to look at the effect of IPC on renal function during AAA repair. We would like to use the monitoring techniques outlined below in the patients assigned to IPC in the randomised controlled trial to collect prospective data on how IPC effects heart function.

The patients assigned to the IPC group will have the blood flow to their legs reduced for two five minute periods by clamping the main artery to each leg in turn during the early stages of their operation. Cardiac output and allied haemodynamic data will be measured with a LiDCO monitor. This is a minimally invasive, continuous method of measuring cardiac output and deriving cardiac index, systemic vascular resistance and stroke volume variance. These are routine measures of cardiac function. This monitor uses clinically insignificant doses of intravenous lithium that are non toxic and do not harm or affect the patient in any way. The monitor is used routinely on patients in the Intensive Care Unit and HDU in Addenbrooke's hospital. The LiDCO is attached to an arterial drip. A central venous d

Primary Outcome(s)

Cardiac output measurement.

Secondary Outcome(s)

Not provided at time of registration

Secondary ID(s)

N0544174260

Source(s) of Monetary Support

Cambridge Consortium - Addenbrooke's (UK) - Own Account