Platelet Function Testing Help and Intraoperative Bleeding Risk for Patients Who Are on Plavix Prior to Surgery

November 6, 2019 updated by: Cedars-Sinai Medical Center

Does Platelet Function Testing Help us Assess Intraoperative Bleeding Risk in Cardiac and Vascular Surgery for Patients Who Are on Plavix Prior to Admission?

A large number of patients are currently on Antiplatelet inhibition using aspirin or Plavix therapy (A Thieno pyridine - ADP mediated platelet inhibitor). A group of these patients often require Cardiac and/or Vascular surgical procedures. These patients are at a higher risk for perioperative bleeding complications and higher re-operation/re-exploration for bleeding and subsequent blood product transfusions.

The aim of this protocol is to assess platelet function via the "Verify Now" device prior to surgery. The Verify Now device requires a small drop of fresh blood for each sample and is an FDA approved device.

The investigators initial goal is to establish if a certain degree of platelet function abnormality can predict a higher bleeding complication or higher transfusions (Phase I, 20 patients). This initial study will allow us to determine a sample size for Phase II. Phase II will maintain the same protocol, however after completion of Phase I, a more accurate sample size determination can be made. Additionally, the investigators want to establish if knowledge of platelet dysfunction will change procedure technique or preparation to lower bleeding and/or lead to cancellation/rescheduling of procedure (Phase III).

Participants will be those patients who are taking plavix and are undergoing vascular or cardiac surgery. They will undergo a platelet function evaluation measured as Platelet Response Unit (PRU) via the "verify now" device on admission/pre surgery. This test involves taking 1 drop of blood from the patient, one time, before the procedure. The Verify Now device is FDA approved.

Perioperative bleeding will be assessed by absolute drop in hematocrit immediate post-op compared to the immediate preoperative value. An additional discharge hematocrit will be used if no blood products have been used during the initial hospital stay. Hematocrit evaluation via a complete blood count is a part of standard patient care. Additionally, utilization of blood products (factors, PLT, PRBC's, etc.) will be assessed.

In order to conduct the research, patients will be identified by reviewing the OR schedule. All consecutive patients on ASA/Plavix will be mailed a letter in order to introduce them to the study. The letter provides a phone number to call if the patient does NOT want to receive a phone call from the investigative staff. This letter is uploaded under item 18-02 of the study application. If patients do not call the office, then the investigative staff will call the potential participants to introduce the study. Final consent will be completed in PACU on arrival at the hospital for planned surgical procedure.

A Hematocrit will be performed on the consented patient preoperatively, immediately post-op, and at discharge. A PRU will be assessed using a few drops of the patients' blood preoperatively (PACU). Patients' records will be reviewed to assess use of blood products. No additional follow up is required.

Patients' care will be no different than current standard of care, other than the 1 "verify now" test, which is done before the procedure.

Study Overview

Status

Withdrawn

Conditions

Perioperative Bleeding

Study Type

Observational

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

United States
- California
  - Los Angeles, California, United States, 90048
    - Cedars-Sinai Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Participants will be those patients who are taking plavix and are undergoing vascular or cardiac surgery.

Description

Inclusion Criteria:

All consenting participants who are taking plavix prior to undergoing vascular or cardiac surgery.

Exclusion Criteria:

All consenting participants who are NOT taking plavix prior to undergoing vascular or cardiac surgery.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Observational Models: Cohort
Time Perspectives: Prospective

Number of groups / cohorts

Cohorts and Interventions

Group / Cohort
1 All patients undergoing elective, invasive cardiac procedure on plavix prior to admission

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Perioperative bleeding (absolute drop in hematocrit, utilization of blood products (factors, PLT, PRBC's, etc.) will be assessed. Time Frame: measured until discharge	measured until discharge

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Cedars-Sinai Medical Center

Investigators

Principal Investigator: Suhail Dohad, MD, Attending physician

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2008

Primary Completion (Actual)

June 3, 2009

Study Completion (Actual)

June 3, 2009

Study Registration Dates

First Submitted

April 2, 2008

First Submitted That Met QC Criteria