Effect of Real-fire Training on Vascular Function

Summary

Fire-fighters are at increased risk of death from heart attacks when compared to other emergency service professionals whose jobs involve similar components such as emergency call-outs and shift work. The unique risk to fire-fighters is likely to reflect a combination of factors including extreme physical exertion, mental stress, heat and pollutant exposure.

In the largest analysis of cause of death amongst on-duty fire-fighters, fire-fighter deaths were classified according to the duty performed during the onset of symptoms or immediately prior to any sudden death. The majority of deaths due to a cardiovascular cause (i.e. heart attack) occurred during fire-suppression whilst this activity represented a relatively small amount of a fire-fighters professional time. Fire simulation training centers offer a unique opportunity to assess the heart, blood and blood vessel response to fire suppression in a controlled environment.

In this study the investigators will assess healthy career fire-fighters on two occasions: following a fire-suppression training exercise in a purpose built real-fire training center, and following a sedentary period as a control. The investigators will take blood samples to measure platelet activity (platelets are the particles in blood that help blood clot) and will examine how blood clots outside of the body. The investigators will then perform studies placing small needles in the arm to assess blood vessel function following fire suppression. By undertaking this comprehensive assessment of blood, blood vessel and heart function we hope to understand the mechanisms whereby the risk of a heart attack is influenced by fire suppression. The investigators hypothesize that following the fire-suppression exercise firefighters blood will clot more readily and their blood vessels will not relax properly which are two of the main processes in the development of a heart attack.

Conditions

• Vascular Function
• Atherothrombosis

Interventions

PROCEDURE

Forearm Vascular Study

Forearm venous occlusion plethysmography to measure forearm blood flow during intra-arterial infusion of the vasodilators Verapamil (10-100 µg/min), bradykinin (100-1000 pmol/min), sodium nitroprusside (2-8 µg/min) and Acetylcholine (5-20 µg/min).

PROCEDURE

Badimon Chamber Study

Ex-vivo assessment of thrombus formation using the Badimon Chamber

Sponsors & Collaborators

• University of Edinburgh

  lead OTHER

Principal Investigators

• David E Newby, MD PhD · University of Edinburgh

• Nicholas L Mills, MBChB PhD · University of Edinburgh

• Amanda L Hunter, MBChB · University of Edinburgh

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

60 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2012-04-30

Primary Completion

2016-09-30

Completion

2016-09-30

Countries

• United Kingdom

Study Locations