Preconditioning Shields Against Vascular Events in Surgery

Summary

Major vascular surgery involves operations to repair swollen blood vessels, clear debris from blocked arteries or bypass blocked blood vessels. Patients with these problems are a high-risk surgical group as they have generalized blood vessel disease. These puts them at risk of major complications around the time of surgery such as heart attacks , strokes and death. The mortality following repair of a swollen main artery in the abdomen is about 1 in 20. This contrasts poorly with the 1 per 100 risk of death following a heart bypass. Simple and cost-effective methods are needed to reduce the risks of major vascular surgery. Remote ischaemic preconditioning (RIPC) may be such a technique. To induce RIPC, the blood supply to muscle in the patient's arm is interrupted for about 5 minutes. It is then restored for a further five minutes. This cycle is repeated three more times. The blood supply is interrupted simply by inflating a blood pressure cuff to maximum pressure. This repeated brief interruption of the muscular blood supply sends signals to critical organs such as the brain and heart, which are rendered temporarily resistant to damage from reduced blood supply. Several small randomized clinical trials in patients undergoing different types of major vascular surgery have demonstrated a potential benefit. This large, multi-centre trial aims to determine whether RIPC can reduce complications in routine practice.

Conditions

• Abdominal Aortic Aneurysm
• Carotid Atherosclerosis
• Critical Lower Limb Ischaemia

Interventions

PROCEDURE

Remote preconditioning

Immediately after induction of anaesthesia, a standard, CE-approved tourniquet cuff will be placed around one arm of the patient. It will then be inflated to a pressure of 200mmHg for 5 minutes. For patients with a systolic blood pressure \>185mmHg, the cuff will be inflated to at least 15mmHg above the patient's systolic blood pressure. The cuff will then be deflated and the arm allowed reperfuse for 5 minutes. This will be repeated so that each patient receives a total of 4 ischaemia-reperfusion cycles. In all other respects, the procedure and peri-operative care will follow the routine practices of the surgeons and anaesthetists involved.

Sponsors & Collaborators

• Mid Western Regional Hospital, Ireland

  lead OTHER

Principal Investigators

• Stewart R Walsh, MCh FRCS · Mid Western Regional Hospital and University of Limerick

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2012-02-29

Primary Completion

2014-11-30

Completion

2014-11-30

Countries

• Ireland

Study Locations