Clinical Trial Details
— Status: Not yet recruiting
Administrative data
| NCT number |
NCT01006083 |
| Other study ID # |
TASMC-09-IM-0540-CTIL |
| Secondary ID |
|
| Status |
Not yet recruiting |
| Phase |
N/A
|
| First received |
October 30, 2009 |
| Last updated |
October 30, 2009 |
| Start date |
January 2010 |
| Est. completion date |
February 2012 |
Study information
| Verified date |
October 2009 |
| Source |
Tel-Aviv Sourasky Medical Center |
| Contact |
Zvi Lidar, MD |
| Phone |
97236974134 |
| Email |
zvil[@]tasmc.health.gov.il |
| Is FDA regulated |
No |
| Health authority |
Israel: Ministry of Health |
| Study type |
Observational
|
Clinical Trial Summary
The objective of this study is to evaluate the safety of antiplatelet (APA)therapy
continuation in patients undergoing lumbar spine surgery (laminectomy, discectomy and
foraminotomy), and to gather evidence-based data regarding postoperative outcomes
potentially related to APA management.
Description:
BACKGROUND Antiplatelet agents (APAs) are widely prescribed for coronary stenting, primary
and secondary prevention of cerebrovascular and coronary artery disease. Dual antiplatelet
therapy (aspirin/plavix) has become the mainstay antiplatelet treatment strategy for the
prevention of stent thrombosis. Maintaining antiplatelet therapy until the end of the
indicated period is crucial for the success of coronary stents. Premature discontinuation of
antiplatelet therapy markedly increases the risk of stent thrombosis, a catastrophic event
that frequently leads to myocardial infarction (MI), with a death rate of 20-40%. Aspirin is
commonly prescribed for lifetime in patients at increased atherothrombotic risk, whereas
Plavix is regarded as mandatory until the coronary stents are fully endothelialized, which
takes 4-6 weeks for bare metal stents and up to 1 yr for drug-eluting stents. And yet,
within the first year after stenting, approximately 5% of patients who have undergone
percutaneous coronary interventions (PCIs) will require noncardiac surgery, thus raising
dilemmas of APA management: stopping APA treatment before operation to avoid bleeding while
risking postoperative stent thrombosis versus maintaining APA therapy perioperatively thus
risking extensive blood loss but limiting the risks of postoperative ischemic events.
Current recommendations are that aspirin should not be discontinued pre-operatively, with
the exception of brain surgery and certain urological operations in which bleeding may be
difficult to control and is therefore life threatening.
The continued use of plavix during the perioperative period significantly increases
intraoperative blood loss, re-operations for the control of hemorrhage and transfusions, but
does not affect morbidity, mortality, or surgical outcomes.
Most guidelines recommend to postpone invasive procedures until the end of the indication
for plavix. Only vital or emergency surgery should be performed on full antiplatelet
therapy, with the exception of procedures in which even a small hemorrhage may have
disastrous consequences (e.g. intracranial surgery, spinal surgery in the medullary canal,
surgery of the posterior chamber of the eye), or procedures involving massive bleeding.
Evidence-based data are needed to guide management of patients in whom early antiplatelet
withdrawal is being considered (e.g. those who require non-cardiac surgery). Several studies
have been conducted in orthopedic and cardiac surgery, however, to the best of our
knowledge, not in spine surgery. This type of surgery might often be semi-urgent and
postponing surgery for long time may be problematic.
This prospective, observational study is designed to evaluate the safety of APA therapy
continuation in patients admitted for lumbar spine surgery.
METHODS
Study design The study will be conducted as an observational one. An informed consent will
be obtained from all patients matching the above criteria. Diuretics and oral hypoglycemics
will be discontinued the day prior to surgery, as dictated by the routines in our patients.
Antiplatelet therapy will be continued as commonly practiced in these procedures. Any
deviation from this protocol will be documented. Throughout the postoperative period study
patients will be observed for any bleeding- or thrombosis-related events, and relevant
perioperative data will documented (see "patient monitoring & assessment").
Peri-operative management Anesthetic and surgical management, including management of
surgical hemorrhage or any other hemodynamic event will adhere to standard practice.
Postoperatively, study patients will be transferred to the post-anesthesia care unit and
later to the neurosurgery department, unless otherwise indicated. In the postoperative
period, departmental routines will guide blood product transfusions, pain management, fluid
regimens and medications administered.
Patient monitoring & assessment
Patients will be allocated into 4 groups:
1. Patients not at risk of coronary and/or cerebrovascular disease, and not taking APAs.
2. Patients at high risk for cardio/cerebrovascular disease (diabetes mellitus, cigarette
smoking, hypercholesterolemia, hypertension, morbid obesity), but not taking APAs.
3. High-risk patients with cardiovascular risk factors (as above), in whom APA is
prescribed as primary prevention of coronary artery disease (CAD).
4. Patients with a history of a coronary syndrome (stable/unstable angina); MI; transient
ischemic attack (TIA)/stroke; severe carotid artery stenosis/stenting; or peripheral
vascular disease, on APAs for secondary prevention.
For each consented patient included in the study we will record demographics and medical
history ; chronic medications ; detailed cardiovascular history ; neurological examination ;
APA-related data: type and dose of APA taken; indication ; Intra-operative data ; and
perioperative complications.
Outcome measures
1. Primary outcomes: hemorrhagic, thrombotic, and neurological complications Include any
complication, morbidity or death potentially caused by continuation (e.g., direct or
indirect hemorrhage; hemorrhagic CVA) or withdrawal of APA therapy (e.g., MI; PE;
ischemic CVA; DVT; etc.), occurring until discharge, or within 30 postoperative days.
Neurological complications may be related to surgery; bleeding; thrombosis; other, and
will be classified accordingly.
2. Secondary outcomes Include: re-intubations; transfer to ICU; length of stay (LOS);
re-admissions within 7 / 30 days; major morbidity or death 30 and 60 days
postoperatively.
Study size The study is expected to last 2 years, and to include approximately 200 patients.
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