Effect of Fire Suppression and Emergency Duties on Vascular Function

Vascular Function Clinical Trial

Official title:

Effect of Fire Suppression and Emergency Duties on Vascular Function in Firefighters

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01805063
• Other study ID #: 11-SS-0049
• Secondary ID: PG/11/27/28842
• Status: Completed
• Start date: January 9, 2012
• Est. completion date: December 31, 2016

Study information

• Verified date: March 2013
• Source: University of Edinburgh
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Firefighters are at increased risk of death from heart attacks when compared to other emergencyy service professionals whose jobs involve similar components such as emergency call-outs and shift work. In the largest analysis of cause of death amongst on-duty firefighters, firefighter 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 firefighters professional time. There was also a risk of death associated with other duties such as emergency non-fire response and physical exertion.

The investigators hypothesize that participation in active fire-fighting duties impairs blood vessel function and increases blood clot formation when compared with non-fire-fighting activities. In this study, healthy career firefighters will be assessed after three periods of duty: fire-suppression, emergency response without fire suppression and following a sedentary shift. 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 these duties. By undertaking this comprehensive assessment of blood, blood vessel and heart function the investigators hope to understand the mechanisms whereby the risk of a heart attack, fatal or otherwise, is posed throughout these distinct duties that firefighters undertake on a daily basis.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: December 31, 2016
• Est. primary completion date: December 31, 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• Non-smoking healthy firefighters

Exclusion Criteria:

• Current smoker

• History of lung or ischaemic heart disease

• Malignant arrhythmia

• Systolic blood pressure >190mmHg or <100mmHg

• Renal or hepatic dysfunction

• Previous history of blood dyscrasia

• Unable to tolerate the supine position

• Blood donation within the last 3 months

• Recent respiratory tract infection within the past 4 weeks

• Routine medication including aspirin and NSAIDs

Related Conditions & MeSH terms

• Atherothrombosis
• Emergencies
• Thrombosis
• Vascular Function

Intervention

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).
• Badimon Chamber
Ex-vivo assessment of thrombus formation using the Badimon Chamber

Locations

Country	Name	City	State
United Kingdom	Royal Infirmary of Edinburgh Clinical Research Facility	Edinburgh

Sponsors (1)

Lead Sponsor	Collaborator
University of Edinburgh

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Forearm blood flow measured by venous occlusion plethysmography in response to infused vasodilators		up to 12 hours after exposure
Secondary	Ex-vivo thrombus formation using the Badimon chamber		up to 12 hours after exposure
Secondary	Plasma t-PA and PAI concentrations following infusion of bradykinin		During forearm study, up to 12 hours after exposure