Evaluation of the Accuracy of the Hemochron Signature Elite Point of Care Device Compared With Laboratory Assay

NCT02255214 | Completed Results

• 1 other identifier: 2013/0300
• Study Type: observational
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

Central Neuraxial Blockade (CNB) is commonly used in anaesthetics. It has several advantages over a general anaesthetic however contraindications include coagulopathy. Guidelines suggest a CNB should not be undertaken with an International Normalised Ratio (INR) of 1.5 or greater. A common cause of an elevated INR is warfarin therapy and regular monitoring of its effects is required. The Hemochron Signature Elite is a portable micro coagulation system that can be used as a point of care (POC) anticoagulation monitoring device. Marketing is focussed on its accuracy, convenience and efficiency in delivering a coagulation result. This study will assess the accuracy of this device in calculating the International Normalised Ratio (INR) result. This will be compared to another INR result obtained on the same sample via the current gold standard testing equipment in the Royal Infirmary Edinburgh (RIE) laboratories. The study will include patients presenting for surgery who have had their warfarin therapy stopped within the previous 7 days. Patients on warfarin therapy requiring surgery are currently identified in preoperative assessment clinics, on average 12 weeks prior to their date of surgery. Anecdotally there appears to be a difference between the 'expected' and actual INR when a POC device is used. Concern exists that patients may be inappropriately denied the potential benefits of central neural blockade (CNB) if a POC device provides a falsely high result, or conversely the investigators may be proceeding with CNB in patients with an unacceptably high INR if POC provides a falsely low result. There is also the possibility of improving hospital efficiency using this device as it provides a result much faster than the laboratory.

Conditions

Blood Coagulation Tests

Outcome Measures

Primary Outcomes (1)

• The International Normalised Ratio (INR) Will be Measured by the Laboratory Assay and the Hemochron Signature Elite Device.

  The correlation between the international normalised ratio measured by the laboratory assay and the Hemochron Signature Elite device was assessed.Number of participants with a higher INR measurement by the Hemochron Signature Elite device than laboratory assay

  18 months

Study Arms (1)

Surgical Patient

These are the results from the blood samples taken from the study participants.

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population will include all adult patients presenting for elective surgery who have stopped their warfarin therapy within the last 7 days. They will be approached in the Day Surgery Unit and Day of Surgery Assessment unit within a single centre.

You may qualify if:

• Adult patients presenting for elective surgery who have stopped their warfarin therapy within the last 7 days.

You may not qualify if:

• Adults with incapacity

Sponsors & Collaborators

• NHS Lothian: lead

Study Sites (1)

Royal Infirmary Edinburgh

Edinburgh, Lothian, EH16 4SA, United Kingdom

Location

Results Point of Contact

• Title: Dr Cameron Ferguson
• Organization: NHS Lothian

cameronferguson@nhs.net

0131 536 1000

Study Officials

• Cameron R Ferguson, MBChB MRCP

  NHS Lothian

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 14, 2014
• First Posted: October 2, 2014
• Study Start: October 1, 2013
• Primary Completion: May 1, 2015
• Study Completion: May 1, 2015
• Last Updated: January 30, 2026
• Results First Posted: January 30, 2026

Record last verified: 2026-01

Locations

GB (1)